With the proliferation of image-based applications in various domains, the need for accurate and interpretable image similarity measures has become increasingly critical. Existing image similarity models often lack transparency, making it challenging to understand the reasons why two images are considered similar. In this paper, we propose the concept of explainable image similarity, where the goal is the development of an approach, which is capable of providing similarity scores along with visual factual and counterfactual explanations. Along this line, we present a new framework, which integrates Siamese Networks and Grad-CAM for providing explainable image similarity and discuss the potential benefits and challenges of adopting this approach. In addition, we provide a comprehensive discussion about factual and counterfactual explanations provided by the proposed framework for assisting decision making. The proposed approach has the potential to enhance the interpretability, trustworthiness and user acceptance of image-based systems in real-world image similarity applications. In many real-world scenarios, the ability to measure image similarity is crucial for decision-making processes, intelligent systems as well as user interactions; therefore, image similarity models constitute a vital role in various computer vision tasks ,2,3,4,5.Siamese neural networks  probablyright to explanation”, which mandates that individuals should be provided with an explanation for automated decisions [Explainability techniques aim to shed light by providing insights into how and why a convolutional-based model makes certain predictions by understanding the features and patterns, which the model learns from the data. These techniques not only enhance our understanding about the model’s decision process but also play a vital role in building trust and accountability in artificial intelligence systems. More specifically, they enable us to verify the reasoning behind the predictions , identifecisions . Finallyecisions ,15.In the literature, several research directions have focused on enhancing the interpretability of deep learning models, particularly in the fields of computer vision ,17. Explexplainable image similarity”. Our primary aim is to bridge the gap between numerical similarity scores and human-understandable explanations. Along this line, we propose a new algorithmic framework, which integrates Siamese networks and Grad-CAM for providing explainability in image similarity tasks. The former are utilized for calculating the similarity between two input images while the latter is used for visualizing and interpreting the decisions made by a convolutional-based Siamese network. An attractive advantage of the proposed framework is that it is able to provide an image similarity score along with visual intuitive explanations for its decisions  together with explanations based on its ability regarding “what if” scenarios . Finally, we provide a comprehensive discussion about factual and counterfactual explanations as well as the valuable insights and recommendations which can be made from the application of the proposed framework on three real-world use case scenarios.In this work, we propose a new concept, named “At this point it is worth mentioning that although the Grad-CAM technique has been widely used and studied in a variety of domains, to the best of our knowledge it has never been utilized for image similarity tasks.explainable image similarity”, highlighting the need for providing human-understandable explanations for image similarity tasks.We propose the concept “We propose a new conceptual framework for explainable image similarity, which integrates Siamese networks along with the Grad-CAM technique, which is able to provide reliable, transparent and interpretable decisions on image similarity tasks.The proposed framework produces factual and counterfactual explanations, which are able to provide valuable insights and be used for making useful recommendations.Summarizing, the main contributions of this work are described as follows:explainable image similarity” as well as a detailed discussion about the proposed framework while The rest of this paper is organized as follows: Convolutional-based Neural Networks (CNNs) revolutionized modern computer vision and are widely regarded as the cornerstone choice for addressing image processing tasks ,5,22,23.Nowadays, explainability and interpretability play a significant role in bridging the gap between the advanced capabilities of DL models and the need for transparency and accountability in their decision-making processes. However, as CNNs become deeper and more complex, understanding how and why they make particular predictions becomes challenging. Grad-CAM  is a novIn computer vision, the concept of image similarity consists of a fundamental building block for various real-world applications, ranging from image retrieval  and pattAppalaraju and Chaoji  proposedMelekhov et al.  proposedRossi et al.  introducIn this research, we introduce the concept of explainable image similarity for providing useful, interpretable and transparent insights into the underlying factors driving image relationships and comparisons. In addition, we propose a new framework which integrates Siamese networks together with the Grad-CAM technique. The former are used for calculating the similarity between input images while the latter is used for visualizing and interpreting the decisions made by convolutional-based neural networks. In contrast to previous presented state-of-the-art approaches, the proposed framework is able to provide an image similarity score along with visual intuitive explanations for its decisions. The presented use case scenarios demonstrate the applicability of the proposed framework as well as a path for providing insights and useful recommendations from factual and counterfactual explanations.In this section, we present the proposed framework which is able to provide similarity scores along with visual transparent and understandable explanations for its decisions. We recall that our primary goal is to propose the concept of explainable image similarity for bridging the gap between numerical similarity scores and human-understandable explanations. By offering interpretable explanations, explainable image similarity not only enhances the usability of similarity-based applications but also empowers users to comprehend the reasoning behind the model’s decisions, ultimately fostering informed and confident decision making.In the following, we briefly present the main components of the proposed framework which is based on the integration of the Grad-CAM technique to Siamese networks as well as a detailed description, paying special attention to its capabilities and advantages.Siamese neural networks [networks  constitunetworks ,9,29. Thnetworks ,27,30,31Gradient-weighted Class Activation Mapping (Grad-CAM) [y with respect to the k-th map activations i) and height (index j) dimensions, that is,Z is the total number of spatial locations in the feature maps. Then, we perform a weighted combination of forward activation maps, and follow it by ReLU activation function for calculating rad-CAM)  is a powBy utilizing the gradients with respect to the model’s internal feature maps, Grad-CAM generates an activation map, which highlights the discriminative regions responsible for the model’s decision.Next, we provide a detailed description of the proposed framework while a high-level presentation of its architecture is highlighted in what would have not happened when a certain decision was taken” [y with In addition, the proposed framework is able to provide counterfactual explanations. Actually, a counterfactual explanation provides a description of “s taken” . This trCounterfactual explanations: The identification of regions, which would make the network change its prediction, could highlight concepts that confuse the model. Therefore, by removing those concepts, the model’s decisions may be more accurate or more confident.Bias evaluation of model’s decisions: In case the Siamese model is performing well on both training and testing data (not-biased model), Grad-CAM heatmaps may be used to visualize the features, which significantly impact the model’s decisions. In contrast, in case the Siamese model is performing well on the training data but it is not able to generalize well (biased model), Grad-CAM heatmaps can be efficiently used to identify unwanted features in which the model focuses on.Flowers. This dataset contains 4242 images (320 × 240) of flowers, which were categorized into five classes: “chamomile”, “tulip”, “rose”, “sunflower” and “dandelion”.Skin cancer. This dataset concerns images (224 × 224) of 1400 malignant and 1400 benign oncological diseases.AirBnB. This few-show dataset is composed of 864 interior and exterior house pictures (600 × 400) scraped from AirBnB over 3 cities, which were classified in 12 classes: “backyard”, “basement”, “bathroom”, “bedroom”, “decor”, “dining-room”, “entrance”, “house-exterior”, “kitchen”, “living-room”, “outdoor”, “staircase” and “TV room”.Next, we provide some use case scenarios from the application of the proposed framework to three (3) well-known datasets from different real-world application domains:https://github.com/ioannislivieris/Grad_CAM_Siamese.git (access in 14 August 2023).The presented use cases focus on highlighting how the proposed framework could be used for image similarity tasks, what useful conclusions could be drawn by factual and counterfactual explanations and finally, what useful recommendations could be provided. For training the Siamese networks, 80% of each dataset’s images were used for training and the other 20% for testing while preserving the variance of each class in each set. In addition, 10% of training images were used as a validation set for optimizing the network’s performance. The implementation code along with the datasets can be found in d is the Siamese model’s output. Notice that this methodology was initially proposed by Melekhov et al. [Based on the images of each training dataset, we created the training pairs as follows: For each image, two images were randomly selected; one image from the same class and another image from a different class. The first pair containing the images from the same class was assigned with label zero (0), while the second pair containing the images from different classes was assigned with label one (1). Along this line, the similarity between two random input images is defined by v et al. .At this point, it is worth mentioning that the model’s prediction can be exploited to obtain information if two images belong to the same class or not. More specifically, if the prediction of the Siamese network for a pair of images is less than a pre-defined m is the margin value, which was set to 2.Regarding the Siamese network architecture, ResNet50  was usedlgorithm  while a lgorithm  was usedNext, we present an example from the application of the proposed framework on two random images a,d from By taking into consideration that similar conclusions can be drawn by randomly selecting any pair of images in the Flowers dataset, a possible recommendation for improving the model’s performance could be that the model is based on identifying the blossoms in the input images for making its prediction; thus, a removal of other characteristics such as stems, background, etc., may improve the model’s performance.Notice that although the input images look similar for a non-expert human, the tumor’s characteristics such as texture, color and size are considered vital for separating benign from malignant cases. Therefore, a possible recommendation from this use case could be to use data augmentation based on transformation techniques  in order to improve the model’s performance.Since the model’s prediction is not very confident, it is wise to study the counterfactual explanations to explore why the model was near to being confused. A possible recommendation for improving the model’s performance could be to use advanced image processing techniques for item identification in order to assist the model of correlating the items and/or furniture, which belong to each room.In the rest of this section, we present an example of improving the performance of the Siamese model through the conclusions and recommendations, which could be provided from the application of the proposed framework.Firstly, we recall that in the use case scenario performed on the Flowers dataset, we observed that by randomly selecting any pair of images which belong to the same class, the Siamese model focused on the blossoms for making its decision . Hence, To examine the effectiveness of this approach, we create a new dataset in which each figure is replaced with a bounding box containing the flower’s blossom. For calculating the bounding boxes for each image in the training data (anchor image), another image from the same class was randomly selected for calculating their similarity. In this case, their predicted similarity by the model was >80%, then we calculated the anchor’s image Grad-CAM heatmap. Based on the calculated heatmap, we utilized the methodology and implementation of Cui et al.  for obtaSummarizing the previous discussion, we are able to conclude that the recommendation of removing characteristics such as stems, background and focusing on the blossoms considerably improved the quality of the dataset.The motivation for this research was to introduce the concept of explainable image similarity for providing useful, interpretable and transparent insights into the underlying factors driving image relationships and comparisons.In this modern deep learning area, models are becoming more and more complex. They can exhibit high accuracy but their lack of transparency and explainability becomes crucial for building trust and understanding. The context of explainable image similarity aims to bridge the gap between the black-box nature of sophisticated similarity models and human interpretability. The main goal is not only the development of models which are able to provide accurate similarity scores between pairs of images but also to offer insights into the specific features, patterns or attributes that contribute to the computed similarity. By offering interpretable explanations, explainable image similarity not only enhances the usability of similarity-based applications, such as image retrieval and recommendation systems, but also empowers users to comprehend the reasoning behind the models’ decisions, ultimately fostering informed and confident decision making.For achieving this goal, we proposed a new framework by integrating Siamese networks together with the Grad-CAM technique. The former are used for calculating the similarity between input images while the latter is used for visualizing and interpreting the decisions made by convolutional-based Siamese neural networks. An attractive advantage of the proposed framework is that it is able to provide an image similarity score along with visual intuitive explanations for its decisions. In addition, the proposed framework is able to evaluate bias on the model’s decisions as well as provide counterfactual explanations, highlighting the ability of the “what if/model’s decisions”. The presented use cases scenarios included the application of the proposed framework on three similarity tasks from different application domains (two classification datasets and a few-shot learning dataset). Notice that the scope of this research was not to address a specific class of benchmarks, i.e., few-shot learning benchmarks, one-shot learning benchmarks, etc., but to provide human-meaningful explanations on similarity tasks. Clearly, the proposed framework can easily be applied to any image similarity tasks as well as few-shot/one-shot image classification tasks providing similarity scores along with visual explanations about its decisions. The use cases scenarios along with the provided comprehensive discussion highlighted the need for explainable image similarity and the useful conclusions and recommendations, which can be provided by its application. Furthermore, we presented an example of improving the performance of the Siamese model for the Flowers use case scenario through the conclusions and recommendations provided from the application of the proposed framework. In more detail, the provided recommendations resulted in increasing the model’s accuracy by 1.2% and its prediction ability to identify similar images. For the Skin cancer and AirBnB use case scenarios, the recommendations for improving the models’ performance were to use data augmentation based on transformation techniques  and image processing techniques for item identification in order to correlate the items and/or furniture, which belong to each room, respectively. Nevertheless, the former resulted in a minor improvement of the model’s performance while the latter needs expert image processing and object identification techniques; hence, we decided to omit them.It is worth mentioning that the proposed framework is based on the original Grad-CAM for providing visual explanations. Clearly, other state of the art techniques such as Grad-CAM++ , XGrad-COur future work is concentrated on the application of the proposed framework on real-world image similarity benchmarks and its usage in conjunction with non post hoc explainable techniques ,16. Sinc


Finding new meaning and identity in the aftermath of trauma has been identified as a key process of mental health recovery. However, research indicates that this meaning-making process is compromised in people with psychosis. Considering the high prevalence, yet under-treatment of trauma in people with psychosis, it is urgent to gain insight into how their meaning-making process can be supported.To gain insight into how people with psychosis make meaning of trauma and identify barriers and facilitators in their meaning-making process.N = 21 interviews transcripts from the Dutch Psychiatry Storybank. We included interviews of people who (a) lived through multiple psychotic episodes, and (b) spontaneously addressed traumatic experiences in a low-structured interview. Storyline analysis was performed to gain insight into the meaning-making of trauma within their self-stories. Psychosocial conceptualizations of narrative identity were used to inform the analysis. A data-validation session with four experts-by-experience was organized to check and improve the quality of our analysis.Qualitative inquiry of We identified four different story types: (1) Psychiatry as the wrong setting to find meaning; (2) The ongoing struggle to get trauma-therapy; (3) Exposure to trauma as a threat to a stable life, and (4) Disclosure as the key to resolving alienation. Each story type comprises a different plot, meaning of trauma withing the self-story, (lack of) integration and barriers and facilitators in the meaning-making process. Overall, barriers in the meaning-making process were mostly situated within mental healthcare and stigma-related. People felt particularly hindered by pessimistic ideas on their capacity to develop self-insight and cope with distress, resulting in limited treatment options. Their process of adaptive meaning-making often started with supportive, non-judgmental relationships with individuals or communities that offered them the safety to disclose trauma and motivated them to engage in a process of self-inquiry and growth.The outcomes illuminate the social context of the meaning-making challenges that people with psychosis face and illustrate the devastating influence of stigma. Our outcomes offer guidance to remove barriers to adaptive meaning-making in people with psychosis, and can help clinicians to attune to differences in the meaning-making of trauma. ResPrevious qualitative research inquiring these perspectives identified that finding new meaning and identity after disruptive experiences is a key aspect of the process of personal recovery from schizophrenia and other forms of severe mental illness –26. MoreWith the present study, we aim to provide deeper insight into how people with psychosis make meaning of trauma. Specifically, we are interested in narrative meaning-making of trauma in the context of the stories people create about their selves and lives. By telling stories, people connect life events into a meaningful whole, leading to a certain extent of narrative integration . In ordeNarrative identity has been defined by McAdams as: “The internalized and evolving story of the self that a person constructs to make sense and meaning out of his or her life (…) and that serves to explain, for the self and others, how the person came to be and where his or her life may be going.” , p. 99. In psychological guidelines and research, traumatic events are described as experiences that can challenge a persons’ view of the world as a just, safe, and predictable place  and disrAs much as self-narratives can become disrupted by traumatic experiences, then, they simultaneously have the potential to negotiate or resolve such disruptions or “breaches” . In factWe only found one study that specifically inquired narrative meaning-making of traumatic experiences by people with psychosis. In this study, the authors found that participants reported high levels of traumatic childhood experiences in a questionnaire, but rarely mentioned, let alone integrated them in their personal narratives . DifficuPrevious research on meaning-making efforts has mainly focused on the integration of illness-experiences into the self-stories of people with psychosis. Decades ago McGlashan et al.  already In this study we will work from a recovery-oriented perspective, assuming that adaptive meaning-making of traumatic experiences is a possibility for people with psychosis. Drawing on psychosocial conceptualizations of narrative identity, we understand adaptive meaning-making as a dynamic and dialogical process of integrating traumatic experiences into the self-story, in a way that makes them more bearable and elicits social support.Our research questions were: (1) How do people with psychosis make meaning of traumatic experiences in the context of their self-stories? (2) What have they experienced as barriers and facilitators in their meaning-making process? (3) What differences in (lack of) integration of traumatic experiences into the self-story can be identified?We performed a qualitative, narrative study of stories from people with psychosis. A common practice in the study of narrative identity is to code and rate narratives with standardized instruments, thus quantifying them . HoweverThis study is part of the “Psychiatry Storybank” from the University Medical Center of Utrecht (Netherlands). In this ongoing, long-term project we collect stories of service-users through low-structured interviews. Our aim is to gain in-depth understanding of service-users’ perspectives on mental illness, care and recovery, in order to improve psychiatric services. The project was evaluated by The Medical Ethical Review Committee of the University Medical Center of Utrecht, who confirmed that the Dutch Medical Research Involving Human Subject Act (WMO) did not apply. Subsequently, official approval of this study by the Medical Ethical Review Committee was not required (reference number WAG/mb/16/030724).Participants in the project were people that made use of psychiatric services in the Netherlands. Apart from acute crisis, no exclusion criteria were formulated. Participants were recruited through convenience sampling: People could sign up through our project website, advertised on  media and by word-of-mouth. Participation was voluntarily and people were informed about their possibility to withdraw from the study at any time. After signing up, participants were first contacted by phone to discuss the aim and process of participation. An information letter with detailed information about participation and privacy was sent afterward. When people gave their consent to participate, the interview was planned and conducted at a place of the participants choosing. During the COVID-19 pandemic, participants were offered the possibility to be interviewed online, through video-calling. All participants gave their written informed consent. The interviews were transcribed verbatim and stored anonymously in our secured database.The interviews were conducted by junior mental-health professionals that were trained and supervised by the Psychiatry Storybank team, including the first author. Interviewers were trained to invite participants to share what matters to them and connect as much as possible to their evolving story, while further exploring and deepening this story using five topics . That’s what it comes down to. And if you then also go through a divorce, which means you have to um, leave your house behind and your whole past in fact (…) then you have to work very hard to get through that. And, and, well, make a new story for yourself, of who you are and what happened to you and, and why and how that happened and where you stand now (…). And I do have an explanation in retrospect as to why I was so explosive at the time. Because the situation in which I regained consciousness  was exactly the same as when I regained consciousness at the age of 5, after being in a very serious car accident. So that, that can be, traumatic. That, that’s my explanation (…) I came to the conclusion that it had everything to do with myself, with my life story.”“Jonathan” (71 years old).Several aspects of the mental healthcare setting were experienced as barriers in the meaning-making process. Firstly, narrators reported experiencing how the predominant feeling of unsafety elicited by acute mental healthcare settings, led to further withdrawal, distrust and isolation, instead of dialog and meaning-making. (Coercive) admission and the seclusion it entailed, was often experienced as traumatic, and as causing a downward spiral of mental distress.“And um, then in 2001 I was isolated for the first time. And that really um, that really took me a long time to get over that. That really put the whole- I always call it ‘the revolving door of psychiatry’- in motion (…). It is like it fueled a kind of separation anxiety. So, I really didn’t dare to be alone anymore. Only when I was stoned or drinking, I could be with myself, alone.”“Maya” (52 years old).Second, a short-term medical approach to their suffering was experienced as hindering. Although most narrators continued to make use of psychiatric services, they felt that their treatment had been too narrowly focused on symptom-reduction, by exclusively providing crisis admissions and medication. Third, narrators experienced stigma in mental healthcare. They felt reduced to their illness and approached as incapable of developing self-insight. For instance, because they were not asked about their life-history and professional insights were not shared with them.In contrast, peer-support groups were experienced as the most important facilitator in the quest for meaning. Peer-support settings were experienced as safe spaces, were everyone was treated with equal respect. These basic conditions set the scene for enhancement of self-insight through mutual validation and exchange of experiential knowledge. Developing a meaningful self-story was an explicit aim of these groups. In this process, narrators experienced writing and creative self-expression as helpful means.Characteristic of these stories was a combination of high thematic coherence with a low degree of detail of traumatic events and experiences. Narrators clearly reflected a lot on their selves and lives and had experienced the benefits of integrating past-experiences into their self-story as part of their recovery process. Narrative dominance of the stigmatizing idea that people with psychosis are not able to make-meaning had hindered them, but was resisted through these counter-narratives. Although narrators had created causal coherence between who they were, how illness and care experiences impacted them, and how this affected their future intentions and (im)possibilities, in most stories there was limited elaboration on the traumatic childhood experiences they mentioned. They tended to seal over those experiences in the context of the interview: traumatic events and the feelings and thoughts they evoked remained vague.Narrators of these stories had all experienced psychical assault, including sexual abuse.The quest for trauma-therapy was central to these stories. Protagonists emerged as active agents that put a lot of effort in gathering the right means to process trauma. They developed specific ideas about how trauma affected them and what kind of trauma-therapy they would need. However, their quest was hindered by mental healthcare professionals that refused or discouraged trauma-therapy or did not offer adequate support.“So, when it comes to medication and having confidence in my recovery, I definitely appreciated him . But when it comes to explanatory models and what, what you can do… I also asked him repeatedly: What can you do for early childhood trauma? And then he said well, we don’t have any treatment for early childhood trauma. So, I can’t offer you anything. Then I went to the GP to refer me for EMDR for early childhood trauma (…). And yes, we’ve approached something like five or six practitioners. But they didn’t respond, or they said well, we think the risk is too high, because you are psychosis prone.”“Marjan” (51 years old).“They first helped me with creative therapy. Then I could be referred for EMDR and confrontation therapy. But I dissociate sometimes (.) and hyperventilate, and sometimes um, it gets so intense that I get a kind of epileptic seizure. So, I um, want to get through it, but I also asked for help -in case I would have such a seizure- to get out of it. But they wouldn’t, because they’re not going to hold your hand, that’s how they told me. So, it turned out I would be sent home in an epileptic seizure. But that’s not possible, you understand? I can’t handle that. So, I do need the EMDR and, and exposure therapy, but not that way.”“Roos” (48 years old).Excluded from the desired trauma-therapy, protagonists often turned to alternative and complementary care. Although protagonists sought their own ways of treating trauma, they continued to struggle with trauma consequences, especially with physical stress reactions.Trauma was central to these self-stories. For narrators, there was a clear relationship between trauma and psychosis. They understood psychosis as both a consequence of trauma and a coping mechanism: an “escape” or “flight” from unbearable traumatic pain. Distinctive for these stories, and apparently related to the experience of physical assault, was that trauma experiences were talked about primarily as bodily experiences that kept inhabiting their bodies and elicit fear. Voices or visions were seen as having meaningful content and realistic elements, related to past trauma. Recovery from trauma for these narrators meant to be able to confront and process trauma without having to escape into another reality. Narrators were hopeful that once trauma was processed, psychosis would no longer occur.Negative responses of parents and other family members on traumatic events were important initial hinderers that narrators encountered in the aftermath of (childhood) trauma. They described interaction patterns of silencing, denial, neglect, or victim-blaming and condemnation, for example in cases were sexual abuse came out. Consequently, narrators came to feel guilty and ashamed about their experiences. Stigma became a barrier once their mental distress became visible for others. Narrators felt that their troubled behavior was not comprehended by others, leading to further despair. Traumatic experiences underlying their distress remained unexplored in mental healthcare, and traumatic stress was not recognized. Once they had been diagnosed with psychotic disorder narrators felt reduced to the “crazy” or “troublesome” person, whose attempts at meaning-making were devaluated and seen as a symptom of illness.“So, you’re there, with post-traumatic stress disorder and pain, neuropathic pain disorder. And you’re not being helped for that. Um, also eventually um, yeah, I got the report eventually. Yeah, nothing at all had been written about a violent crime . So that information, nothing of it was written down there (.) And yeah, then you end up standing outside, because you’re not getting anywhere. Eventually you’re taken out of your house by the police about ten times, or picked up from the street. Um, [silence] because I did start drinking a lot. And [silence] so then you’re actually taken out of your house. And you start to wish: if only I were dead.”“David” (47 years old).Related to (self-)stigma was the lack of psychoeducation on trauma-related coping mechanisms, particularly on dissociation: Narrators thought this information could have helped them in an earlier stage to understand their experiences not as crazy, but as normal reactions to abnormal circumstances.“When I was abused as a child, I found myself in another place. In my mind it wasn’t me that it had happened to. Much later, I learned that this is called dissociation. But as a child, I felt very strange: suddenly you open your eyes, where am I? So, I didn’t understand what happened to me, but I also didn’t know who to talk to, because I just thought I was crazy. So, I think a lot of mistakes were made there, and that if I would have had better guidance, I could have been spared for what came next.”“Roos” (48 years old).An important turning point in these stories was the encounter with a supportive, non-judgmental partner, professional or community that made narrators feel accepted for who they were, beyond their problems. In particular, spiritual or religious communities played an important role by acknowledging the meaningfulness of their distress. Feeling more motivated and hopeful, narrators started to engage in a process of self-inquiry and education on mental distress, finding out more about trauma-related mechanisms, coping and treatment options. Some of them started to write and talk about trauma, others could not speak about it initially, but found it liberating to express themselves through dance, painting or other creative means.Once narrators were able to verbalize their trauma history, trauma, and in most cases PTSD was acknowledged in mental healthcare. However, new barriers arose at this point. Most importantly, narrators felt hindered by risk-avoidance, both as an attitude of individual practitioners and an institutionalized practice in the form of strict inclusion and exclusion criteria for trauma-treatment programs, disadvantaging people with complex psychopathology. They were particularly confronted with the assumption that people with psychosis are not able to (learn to) cope with trauma.“If disasters happen, well, there’s a whole trauma team ready to help the victims. Well, for me, there wasn’t. And during that period when I was psychotic, um, I think there was also the belief that people who are psychotic couldn’t do trauma processing, because they were afraid that they would become psychotic again. Well, that’s bizarre anyway. So, you go through something very shocking [silence] and everybody actually says: don’t talk about it.”“Jeanet,” (52 years old).As narrators educated themselves on trauma and psychosis, they felt hindered by the slow pace in which new scientific insights were integrated in guidelines and translated into practice. Within the mental healthcare that was accessible to them, narrators experienced integrative psychotherapies (such as scheme therapy) as beneficial, especially in terms of validating and regulating emotions associated with trauma. Some narrators finally had the chance to engage in EMDR for a single traumatic experience, that helped them to process it. However, a problem for most narrators was that they had multiple traumatic experiences, and that childhood trauma in particular, was found impossible to verbalize or translate into concrete images. Associated, the lack of innovation and body-focused approaches in mental healthcare was experienced as a barrier. In alternative and complementary care, narrators felt helped because of the holistic approach that facilitated body-mind integration. Learning different self-care techniques, such as breathwork, meditation or reiki made them feel more agentic in calming down their bodies. This made narrators more confident in their capability to further confront and process trauma.“My whole body gets in a kind of panic or something, and starts to shake all at once. So that’s one big startle reaction. Especially when I’m touched, I can’t stand that anymore. I um, [silence] I can handle it a little bit, but it’s not gone away yet (.) Eh, but that’s still um. I just think it’s unfortunate that I just can’t get real professional help within the mental health system, can’t get on with that (…)”I did a lot of things like shiatsu massage. Or um, I’ve done other. I did the whole training on shamanism. That also helped me a lot (…). They’re especially good at early childhood trauma. Because there’s almost always dissociation. And that’s where I also suffer from: dissociative thoughts. And, well, what a shaman is trained in, is to figure out where these experiences went. And how can you get that back again so to speak (.). So, I thought, if I make the technique my own, then I also don’t depend on others. Then I can apply it to myself.”“Marjan” (51 years old).Clearly, trauma was central to these stories. Unlike the other story types, the self-story began with the first traumatic experience, not with the onset of illness. Narrators gave elaborated accounts on trauma, the way they coped with it and its impact on their identity. Distinctive was that narrators described many traumatic events in detail, including the ambiguous and confusing emotions and thoughts that they had experienced during these events. Both causal and thematic coherence were high in these stories. Given the efforts of narrators to inquire and process trauma, this was not a surprising finding. However, narrators emphasized that making meaning of trauma had been a difficult process that had often taken them several decades. Their highly integrated trauma stories can be read as a form of narrative resistance to the idea that people with psychosis are unable to make meaning. However, narrative dominance of the idea that people with psychosis are unable to cope was still hindering them in their quest for trauma-therapy and further body-mind integration.Narrators of these stories were all single persons that had recently started to participate in (online) peer-groups or rehabilitation trajectories. This subgroup included the three stories of people who described traumatic experience without labeling it as such.Friction between different intentions was central to this story type. Narrators typically had been focusing successfully on keeping their psychotic symptoms under control and avoiding relapse and psychiatric admission. Medication, living a tranquil, withdrawn life, and focusing on the here and now had been their most important means to achieve a state of stability. However, at the downside, this lifestyle made them feel isolated from other people and society. Influenced by exposure to new ideas about recovery from peers, narrators began to hope for a more meaningful life. At the same time, they felt anxious about taking new steps that could trigger trauma and compromise their stability.“Um, well, I really want to study actually. But I’m not up to it yet (…). That has to do with um, crowds, stimuli and people and um, fears. I had a bad time in high school. I’ve been bullied for several years. So um, I’m afraid that I’m going to end up in a situation um, yes, that I’ve also experienced in the past. I feel, already feel very vulnerable thinking about that.”“Tim” (40 years old).“I would like to have a job, being able to raise children. Even if it’s just a job for ten hours a week. Even if it’s volunteer work. Doesn’t matter to me. As long as I’m just stable and can get to work. That’s actually the most important, because then I can feel part of society. Then I can also make an active contribution (…). They say I should just do things. But you’re just scared every day that things can go wrong again. That you’ll be locked up again. That fear is so hard to live with.”“Sanne” (22 years old).Narrators associated preoccupation with past trauma with periods of mood disorder and psychotic deregulation. Hence, they believed it was best for their well-being to not look into trauma. They had actively turned away from their past and apparently sought shelter in the present.In these stories, hesitance and difficulty in meaning-making of trauma seemed intertwined. Narrators feared the consequences of attending to trauma. At the same time, they showed difficulty in retrieving and verbalizing memories. Some narrators explicitly mentioned this difficulty. From the evaluation forms of the interviewers, we learned that these interviews were often experienced as demanding and requiring a more active and structured interview style. An apparently related but distinctive hindering factor was narrators’ doubt and confusion about the “realness” of their traumatic experiences, describing their memories as being “blurred,” “diffuse” “delusional” or even “false.”“Before, I was living very much in the past. Um, I had to think very often about my um, early childhood which went rather oddly. But they were partly real memories and partly false memories. And um, yes, I’ve lost that now. I live more in the here and now.”“Bas” (46 years old).Helpers were scarce in these stories, however one important and consistent helper across these stories was peer-support. Firstly, because peers offered narrators hopeful perspectives on recovery in psychosis, motivating them to explore new future possibilities. Secondly, examples of how others were dealing with trauma made them begin to reconsider their own strategies. Thus, peer-support seemed particularly helpful in offering role-models.“I’m thinking about…maybe taking some kind of course to write a book or something. That would be good thing. I have two classmates who have written a book and they motivate me to do it too. But then I don’t really know how. I really wonder how I can deal with my pain, cause I’m kind of overflowed. When I go out with my friends, I’m always cheerful, and I think more about my future nowadays (…). I don’t look at that pain so much. I know that the pain is there, that it does hurt. But then I wonder: what should I do with that? I find that difficult. Some people may be able to deal with that in their own way. But then I am not so much looking at the pain.”“Dolores” (38 years old).As narrators of this story type were not directed toward meaning-making of trauma, barriers and facilitators were harder to identify and interpret in these stories. The data-validation session with experts-by experience played an important role in filling in the gaps of these stories and our understanding of them. They brought forward three important points, based on their own experiences. Firstly, that reluctance to speak about trauma might arise from not being aware of the benefits. Trauma might be perceived as unchangeable life fact that can’t be made “better.” Secondly, they suspected that the fear of trauma memories might consist mainly of losing control over disturbing emotions associated with these memories, such as grief or anger. Thirdly, they suspected that feelings of guilt and loyalty might be involved in the doubt about the realness of traumatic experience. For example, in case of (youth) trauma in which loved-ones are involved, acknowledging the experience as traumatic turns loved-ones into perpetrators. A lack of witnesses to confirm or validate the traumatic experience was brought forward as another factor that can enhance doubt about the realness of it.These self-stories were mostly centered on illness experiences. Traumatic experiences were the gaps in these stories. Narrators mentioned traumatic experiences indirectly and between the lines, referring for example to “bad” situations or experiences without providing further details. Only when they were invited by the interviewer to elaborate, traumatic experiences became somewhat more explicated. These elaborations were minimal and remained low in causal and thematic coherence. These stories were characterized by narrative dissociation of trauma, a form of disintegration in which trauma-memories seem blocked and (unconscious) psychological defense mechanisms were most clearly at work. At the same time narrators’ stories appeared to be overruled by narrative dominance of a stigmatized illness-identity.Narrators of these stories were females within similar care-contexts: They all started with trauma-therapy (preparation), as part of a multi-disciplinary treatment.Central to this story type was past friction between the protagonists’ intentions and actions. When mental distress started to interfere with their pursuit of a “normal” life, protagonists believed it was best to hide their distress. They took actions that consisted of fleeing physically  or mentally .“I had seen something on TV, a program about schizophrenia. And I did realize that I had that too. And I was afraid they were going to lock me up. And, so I though, either I have to act totally normal or I have to end my life. I had those two choices. And I decided to go back to normal. And that actually worked out at that time. I called off my psychiatrist, threw away my pills and I just went back to living a normal life. Even finished my studies. And then things actually went really well for quite a while (…). I didn’t even remember having had it [psychosis red.] and hence never told my husband about it. Until I got it again.”“Bea” (44 years old).However, on the long term these actions led to a downward spiral of problems  and a sense of alienation of their selves and loved ones. Only when the protagonists stopped hiding their distress and found the courage to disclose traumatic experiences, better care and social support initiated.“I didn’t dare to talk openly about what I had gone through (…). I felt ashamed of the things I had been through. I didn’t want to be pitied and that kind of stuff. And [silence] um, yeah, if you don’t share who you are then you don’t have real relationships either. The appearance, the mask you put on, that jams with the others. But a real conversation where you share your heart and where you show who you are, and the other [silence] can respond to that, I just didn’t have that for years. And then you alienate yourself. And I feel now that really um, clarity and light has come to me um, to the things that I was all tucking away.”“Sarah” (60 years old).Narrators described how the role of trauma in their lives had recently shifted. For a long time, they had seen it as something to be hidden for themselves as much as for others. When this strategy turned out to obstruct, rather than help to live a normal life, their ideas changed. They had come to see trauma as an experience that needs to be disclosed and processed, in order to be able to rebuild their lives. Their wish for a better future became the motivation to address the past.“I’ve also experienced trauma in my life…In the sexual area, when I was very young. Now I can talk about it. And talking also means processing. But in the beginning when I just got that first psychosis, I didn’t dare to talk about it. With my psychologist, we are looking now at some form of trauma treatment. We explore what suits me best and how I can get on top of it (…). I especially want to learn how to cope with the thoughts that came after the trauma. And I also um, want to stay stable to be able to take care of my daughter again.”“Alissa” (25 years old).Narrators did not articulate particular ideas about the relation between psychosis and trauma but spoke of psychosis and trauma as accumulative problems.In these stories, next of kin played a particular negative role in the meaning-making process, by expressing stigmatizing ideas on mental distress. Protagonists felt rejected by their family or partners, making them feel ashamed and afraid to disclose their inner world.“For a very long time I thought I’m going to be the old one again. And my family also hoped that very much. They were waiting for the day that I became my old self again. But I didn’t, I already knew that. Um, and I really became a new person. And for a very long time I didn’t dare to come out (…). And for a very long time I was ignored and not allowed to be there as a person. During the admission, nobody came to see me either, because I wasn’t the person they wanted to see.”“Bea” (44 years old).“I think psychosis it is a very hard, lonely disease that you are condemned for (…). Um, [silence] yes, you, you can’t imagine that there’s really no one at all who thinks well, let’s go and see her. And that for two and a half years. It feels like you’re already dead, only you’re still breathing.”“Marlies” (53 years old).Acceptance of professional help after subsequent losses was an important turning point in these stories. Notably, narrators’ motivation to accept and commit to care was the love and responsibility for another being—a child, God, or even a pet—that gave them the strength to work on recovery and start rebuilding their lives. (Coercive) crisis admissions was described as a hinderer, unless it was embedded in trustful therapeutic relationships and follow-up care. Trauma-sensitive care within a multidisciplinary team was described as a significant helper in the meaning-making of trauma. Unique for this story type was that narrators were actually offered regular trauma-therapies, such as EMDR and imaginary exposure. Narrators felt helped by the involved and cooperative relationship with -and between members of the team, and the integrated manner in which various problems were addressed. Marlies, for example, described how she told the psychologist of her Flexible Assertive Community Treatment (FACT) team that the side-effects of her medication made her too passive to feel motivated for EMDR. Hence her psychologist agreed with her psychiatrist to lower the dose. At the same time, the psychologists involved Marlies’ parents to restore her lost supportive network. Simultaneously, a social worker helped Marlies with daily chores and prevention of eviction by the house cooperative. Thus, the whole team together created the right conditions for effective trauma-therapy.The integration of trauma in these stories is best characterized by their transition. Narrators had moved away from trauma for a long time but were starting to turn toward it. Most of their trauma storylines were not detailed or elaborated yet. However, narrators created thematic coherence by stressing the significant impact of trauma on their lives, and the necessity and intention to process it. Hence, the storylines had begun to be part of the self-stories but were unfinished. One exception was the story of Sara, with a highly integrated and elaborated trauma storyline. In contrast to the other narrators that were beginning trauma-treatment, Sara had already finished trauma-therapy, and experienced the effect of it.”I am very happy with the help that I receive now, and the imaginary exposure therapy I got. And that um, [silence] yes, that I just worked through the pain. Because before, I was always tired. A lot of energy went into pushing away that pain. And now I have that energy left and I feel much better than when I was 20, both physically and psychologically. And that is really a wonderful experience.”“Sarah” (60 years old).A salient characteristic of these stories was the relatively low causal coherence: narrators struggled to integrate ideas of their present and past self. After long periods of radically hiding mental distress, the creation of a story that was able to restore a sense of continuity took them considerable effort. Disintegration of the self characterized this story type. Narrators articulated discontinuity specifically in terms of the self before and after psychosis. Experienced stigma played an important role in this form of disintegration, as the ill-self could not be accepted as part of the self without losing significant others. Unlike in other story types, mental healthcare professionals played an important and destigmatizing role in the meaning-making of both illness and traumatic experiences.The aim of this study was to gain in-depth insight into how people with psychosis make-meaning of trauma. Furthermore, we wanted to understand how adaptive meaning-making, as part of the personal recovery process, can be better supported in mental healthcare.Meaning-making was studied by performing storyline analysis on 21 narratives of people that experienced psychosis and trauma. We identified four story types within our sample, each entailing a different meaning of trauma in the context of the self-story. Narrators of “Psychiatry as the wrong setting to find meaning” spoke of trauma as both a cause and consequence of psychosis. They articulated their suffering mostly in terms of illness- and treatment related trauma and losses. The acknowledgement, rather than the processing of trauma seemed most important for them. Distinctively, narrators of “The ongoing struggle to get trauma-therapy” had come to see psychosis as a way of coping with the unbearable pain of traumatic experiences. Consequently, confronting trauma became vital for their recovery. By contrast, narrators of “Exposure to trauma as a threat to a stable life” associated psychotic crisis with preoccupation about past trauma. They appeared to get stuck in the present, as avoidance prevented the integration of trauma into the self-story, but simultaneously hindered them in creating future possibilities. Lastly, narrators of “Disclosure as the key to resolving alienation” had concluded that their strategy to radically hide mental distress and its traumatic origins was not viable. They spoke of addressing trauma as a necessary step in the rebuilding of their lives. These outcomes are consistent with previous qualitative studies, indicating that people with psychosis often link experiences of illness to trauma , 30 and We also found that most narrators either demonstrated or reported (past) difficulty integrating trauma. Both illness and trauma are disruptive experiences that can translate into disintegrated self-stories . In thisTo offer meaning-specific entries for personalizing trauma-informed care, we analyzed barriers and facilitators of each story type in detail. Here we will discuss three overarching patterns that offer guidance to improve trauma-informed care for people with psychosis: the importance of better relational preconditions, long-term care and access to psychotherapeutically interventions.First, we learned that a process of adaptive meaning-making often started with the experience of supportive, non-judgmental relationships with individuals or communities. In accordance with findings from Campodonico et al. , feelingSecond and interrelated, our outcomes highlight the importance of long-term care. Building supportive relationships requires an organizational context that allows professionals to be attentive and stay present . InsteadThird, the outcomes highlight the importance of better access to psychotherapeutically interventions. Narrators experienced a lack of access to interventions that foster meaning-making in general—such as psycho-educations and psychotherapy–as well as access to specific trauma-focused therapies. Psychosis, by definitions consist of a “breakdown of shared meaning” , and mayEducation on psychological mechanism- especially that of dissociation-came forward as another helper in creating a more viable and destigmatizing meaning of trauma reactions. The illness-focused psychoeducation that is common in mental healthcare can be helpful in the acceptance of mental distress and professional help. However, in the case of trauma in psychosis, this approach might be problematic, both because of underdiagnosed PTSD and the stigma-related negative effect of “illness insight” in psychosis , 83. AddPost-traumatic stress in people with psychosis has been found to be systematically underdiagnosed and undertreated in mental healthcare. In our study, few participants had experience with trauma-focused therapies, such as EMDR and exposure therapy. As we learned, people that suffer from trauma consequences will not always seek help for it. Clinicians can play an important role in encouraging people to engage in therapies that reduce the avoidant behavior that is part of post-traumatic stress reactions. Unfortunately, research indicates that in the case of people with psychosis, avoidance might actually be sustained by clinicians, as a consequence of their own negative expectations or anxiety –89. ThisAlthough meaning-making of trauma is an important element of recovery in psychosis , studiesAnother strength of this study is the use of low-structured interviews, that permitted us to inquire the spontaneous integration of trauma into the self-stories of people with psychosis. In this way, we were able to identify a broad variety of meaning-making repertoires: Previous qualitative research has mostly focused on how people with psychosis make meaning of illness experiences and resulted in distinction between people that seal over illness experiences and people that integrate illness experiences. In relation to trauma, we found more variation and combinations, such as highly integrated and reflexive self-stories with a lack of integration of childhood trauma. Insight in these differences can help mental health professionals to attune to particular challenges in the meaning-making of trauma.Furthermore, insight in the different perspectives of people with psychosis can inform re-conceptualizations of trauma in psychosis. Research on psychosis has become increasingly guided by theoretical application of trauma models . It is iIn order for trauma models to be valuable for patients, they also need also to be profoundly grounded in an understanding of what people with psychosis struggle with in their lives. In line with findings from a qualitative study of Vallath et al. , our outLimitations of our study include issues of representation. The majority of participants were female, middle aged, highly educated and participating in society. Under-represented groups included people with a migration background, that have been found to be at higher risk for psychosis and associated experiences of social defeat . UnintenAnother limitation concerns trauma-assessment. In this study, we identified traumatic experience on the basis of the content of stories people told about themselves. Previous research indicates that traumatic experience does not necessarily become part of the self-story of people with psychosis . StoryteThis study demonstrates various ways in which people with psychosis make meaning of traumatic experience. Stigma in mental healthcare was identified as a major barrier in the meaning-making process, especially the ideas that people with psychosis are not able to develop self-insight and coping. The outcomes highlight the social context of the meaning-making challenges that people with psychosis face. Over the last decades, service-user oriented research has challenged pessimistic views on the possibilities of people with psychosis to recover and has elucidated the self-affirming effect of such ideas. Our results suggest that the same self-fulfilling mechanisms could be at play in the meaning-making of trauma and provides directions to better support this process.n.vansambeek@umcutrecht.nl.The datasets presented in this article are not readily available because of participant confidentiality and privacy. Requests to access the datasets should be directed to NS, The studies involving humans were approved by The Medical Ethical Review Committee of the University Medical Center of Utrecht. The studies were conducted in accordance with the local legislation and institutional requirements. Written informed consent for participation in this study was provided by the participants.NS: Conceptualization, Formal analysis, Investigation, Methodology, Validation, Writing – original draft. GF: Conceptualization, Funding acquisition, Supervision, Validation, Writing – review and editing, Methodology. SG: Funding acquisition, Supervision, Validation, Writing – review and editing, Conceptualization. FS: Conceptualization, Funding acquisition, Supervision, Validation, Writing – review and editing.


In this Specialty Grand Challenge, we outline our vision of the current challenges in the field of Network Physiology  as appliAs populations get older, the association between chronological age and health status becomes increasingly variable . To descIn older adults, frailty is clinically defined as “a condition or syndrome which results from a multi-system reduction in reserve capacity to the extent that a number of physiological systems are close to, or past, the threshold of symptomatic clinical failure” and “as a consequence, the frail person is at increased risk of disability and death from minor external stresses” . On the While the clinical concepts of frailty and resilience are well established, their application to practice has been challenging. There is agreement that the measurement of these complex constructs requires the collection of information across multiple physiological systems. Thus, in the case of frailty it has been argued that essential reserve capacities include musculoskeletal function, aerobic capacity, cognitive and neurological function, and nutritional status . Intrinsreserve as she was able to withstand this (illness/procedure)”. A challenge is that it is often clinically or physiologically very difficult to model or quantify the complex physiological interactions that occurred in the face of the given stressor and during its aftermath.In clinical practice, terms such as “physiological reserve”, “functional reserve” or “functional capacity” are commonly employed to describe patient scenarios where an outcome (positive or negative) is viewed (often retrospectively) in relation to a “stressor” , where the clinician makes an overall “black box” judgement of the ability of the person’s body to adapt to the stressor. For example, “Ms X must have had a good At a single system level, “organ reserve” has been described as the ability of an organ to endure recurring stressful conditions, and restore the normal homeostatic balance and function in a relatively short recovery time . AlthougDynamic interactions between physiological systems in the face of stressors remain poorly empirically studied, mechanistically modeled, or understood. This still renders medical science unable to reliably forecast recovery of tipping points in health and disease, especially in older adults . HoweverFor example, the reserve capacity of the heart has been a focus of interest since heart rate variability static and dynamic multi-scale measures are reduced due to significant decline of parasympathetic tone with aging . CardiacAnother area of interest is syncope, which is a transient loss of consciousness due to cerebral hypoperfusion, characterized by a rapid onset, short duration, and spontaneous complete recovery . InherenPhysiological challenges have also been used to better understand the function and reserve of the nervous system, both in health and disease. For example, visual event-related potential measures and neurocognitive response times have been employed to differentiate healthy vs. diseased states and also to identify better cognitive performance in patients affected by neurological disease  . “StressIn the field of brain health, the concept of “cognitive reserve” refers to the capacity of the brain to buffer age-related changes or even neurodegenerative pathology, thereby minimizing clinical manifestations  that would be otherwise more apparent during cognitively demanding tasks  . For insIn many studies of human physiology, it has become apparent that the functioning of different systems is dynamically interconnected. In one study, enhanced psychomotor speed was associated with higher cardiorespiratory fitness . There iIn younger or non-disabled cohorts, an integrative physiology approach may offer opportunities for the early detection of disease. For example, in people living with HIV, subtle abnormalities in easily obtainable biomarkers may indicate preclinical structural and functional changes in the renal, brain, cardiovascular, and skeletal systems . In neurIn older or more disabled cohorts, more clinically obvious physiological instability is often simultaneously present in multiple systems. For example, cardiovascular and postural instability often co-exist in people living with dementia . OrthostThe incorporation of stressors in integrative physiology studies may not only aid the more accurate identification of frailty but also be helpful in rehabilitation approaches to improve resilience. For example, in one study, exercise intervention proved to be safe and effective to reverse the functional decline associated with acute hospitalization in very old patients . In a caIn aging and frailty, measuring and quantifying dynamic networks of diverse systems with different types of interactions remains a challenge. However, the new field of Network Physiology provides a promising system-wide integrative framework to probe interactions among diverse systems . This ma


Migration models have evolved significantly during the last decade, most notably the so-called flow Fixed-Effects (FE) gravity models. Such models attempt to infer how human mobility may be driven by changing economy, geopolitics, and the environment among other things. They are also increasingly used for migration projections and forecasts. However, recent research shows that this class of models can neither explain, nor predict the temporal dynamics of human movement. This shortcoming is even more apparent in the context of forced migration, in which the processes and drivers tend to be heterogeneous and complex. In this article, we derived a Flow–Specific Temporal Gravity (FTG) model which, compared to the FE models, is theoretically similar (informed by the random utility framework), but empirically less restrictive. Using EUROSTAT data with climate, economic, and conflict indicators, we trained both models and compared their performances. The results suggest that the predictive power of these models is highly dependent on the length of training data. Specifically, as time-series migration data lengthens, FTG’s predictions can be increasingly accurate, whereas the FE model becomes less predictive. The world is at a critical moment in the pursuit of fulfilling the Sustainable Development Goals—SDGs—by 2030 ; environSince its inception, the gravity equation has been the cornerstone for economists to examine the role of income maximization in shaping migration decisions . It not uniformly spontaneous.Although useful for inferring migration drivers, the theoretical foundation of the Fixed-Effects (FE) gravity models is not unequivocal. In particular, these models assumed that all migrants are forward–looking utility maximizers who move voluntarily and spontaneously for better opportunities and livelihoods elsewhere . This asTo address the above-mentioned shortcomings, we derived a Flow–Specific Temporal gravity (FTG) model which has a less restrictive parameterization, compared to the traditional FE models. Specifically, the model exploits only temporal, but not spatial, variation in migration panel data. This feature allows us to study how migration drivers may vary across flows. It also allows us to exclusively infer the temporal dynamics of forced migration .Using EUROSTAT data and climate, economic, and conflict indicators gathered from various data sources, we showed that the performances of FTG and FE models are highly dependent on the length of training data. In particular, as time-series migration data lengthens, the FTG model can make increasingly accurate predictions, whereas the FE model becomes less predictive. Nevertheless, it is important to stress that the FTG model is “Data Hungry”, which implies that its adoption is likely to be slow as most time-series migration data are still short and need time to grow longer.Migration journeys can be highly nonlinear as they are often the product of entangled and sequential decision making process: from an initial intention to a decision, and ultimately to a realized movement –29. For To illuminate the lengthy process of forced migration, we conceptualize a framework in The mechanisms underlying migratory process can be highly complex and contextually contingent. In the case of forced migration, the drivers may evolve overtime. For example, the initial displacement could be triggered by (hard) push factors such as armed conflicts, extreme weather conditions, economic crises, famine, among other abrupt events , 36. TheThe conflict–migration nexus has existed long before the constitution of the 1951 Refugee Convention . TheoretRecent studies have investigated the relation between extreme weather events and migration . EmpiricWhile the theories and empirical evidence mentioned above generally imply an immediate out–migration response to different geopolitical and climatic shocks, they are silent about what happens after initial displacement, namely where people move to and how the location choices are made. In our framework, we assume that the second stage of decision making involves a search process for potential destinations, and evaluations of the benefits and costs of moving to these destinations. This step is similar to solving an income maximization problem postulated by the classic economic theory of migration , which iEconomic theories of international migration have evolved considerably overtime with elements added on to the simple income maximization problem, such as the welfare magnets , income The decision to migrate is likely to be an outcome of an individual’s interactions with macro– and meso–level factors . One exaThe empirical analysis in this article relies on various data sources. For the flows of forced migration, we make use of EUROSTAT asylum statistics. To derive indicators for push and pull factors (as depicted in EUROSTAT routinely compiles information on the number of first–time asylum applications lodged in different EU countries. We combine this information with population data from the world bank to compute the asylum-seeking rate (hereafter ASR). That is, the number of first–time asylum seekers per 100 people remained in a given country of origin.The Geo–referenced Event Dataset from Uppsala Conflict Data Program (UCDP) compiles the fatality figures for each event. We make use of this information to measure the severity of conflict events in different sending countries. Panel A in To measure climate anomalies, we use the Standardised Precipitation–Evapotranspiration Index (SPEI) with a spatial resolution 0.5° × 0.5° grid and a monthly frequency . SPEI isSPEI has been increasingly used to study the impact of slow onset climate change on international migration. A general finding is that people tend to migrate in response to warmer climate—i.e., migration volume increases as SPEI declines . A Furthermore, the interpretation of the linear relation between SPEI and migration might not be straightforward. For example, an inverse relation between the number of asylum seekers and SPEI (as shown in ) would iI(*) is an indicator variable equals to one if this grid g in a given month m is extreme dry (S > 2) or extreme wet (S < −2). Go is the total number of grids and Go × 12 is the grid–months, respectively, for a given origin country o during a given year t.To test whether people may respond to both dry and wet climate anomalies, we make a distinction between positive and negative value of SPEI. Moreover, to examine the non–linearity between SPEI and migration, we categorize the monthly SPEI data for each 0.5 × 0.5 grid as: extreme wet (if SPEI > 2) and extreme dry (if SPEI < -2). We then aggregate extreme dry and wet incidences over all the grids in a given country during a year. The aggregated number of incidences are then divided by total number of grid–months in each country. We interpret this derived indicator as the annual risk of climate anomalies. These risks are formally defined as,Panel C in Income is a key determinant of the attractiveness of each destination. In the economics literature of migration, attractiveness is typically measured by the per capita income difference between the destination and origin (see e.g. –12). FolThe gravity equation in the seminal work of Ravenstein  has beeno to destination d and that of remaining in origin o can be respectively written as,V is the deterministic utility, τ is a dissimilarity parameter with range  to Pr. That is,To link the probabilities of individual migration decisions to macro flow data, we multiply the probabilities in It is important to note that, as we relax the IIA assumption, the denominators in While it is possible to estimate It is well known that, to obtain unbiased parameter estimates, the residuals in the least square estimator must be uncorrelated with all independent variables. To satisfy this condition, empirical gravity models generally include flow-specific constants to adjust for time-invariant factors, such as colonial ties, common language, geographical and cultural proximity, among others , 62. Thiαo,d is a constant specific to each dyad flow between o and d (i.e. the flow fixed-effects).To examine how well the conventional FE gravity models can explain and predict forced migration, we follow the approach in  and estiYd,t and Yo,t−1 are economic variables in destination and origin, respectively. Do,t−1 is a measure of conflicts or geopolitical tensions in origin. So,t−1 are indicators for environmental or climate stressors in origin. ϵo,d,t is an error term which is assumed to resemble the white noise.In the second model, we expand By comparing the performance of It is important to stress that the effects of predictors in A key difference between Eqs Although less restrictive in parameterization, The shortcoming discussed above, however, can be tackled by assuming certain probability distribution of the flow-specific parameters. For example, instead of estimating a set of fixed parameter values, Bayesian modelling may provide an effective way to infer the distributions of parameters . This apAnother drawback of our proposed FTG model is that, similar to the FE model, many interesting determinants of dyad migration flows  will be vanished into the dyad fixed effects. This issue is not critical in our analysis below, as the objective is to examine the difference in models’ performances (FE vs. FTG), rather than to understand the determinants of forced migration. However, we would like to stress that our FTG model would be less valuable should time-invariant migration drivers be the primary concern.As shown in Time–varying costs, e.g., migration policies, travel expenses, among others, however, are difficult to measure. Price information on travel is not readily available on a global scale, particularly for non–conventional routes that displaced people often travel through. To measure migration policy, the empirical literature generally relies on different visa (waiver) programs .Furthermore, when deciding where to move, meso–level factors may play an important role. For example, migrant networks are considered to be vital for refugees to access information and to receive financial and practical support , 66–69. o,d,t,To account for the “Knowable Unknowns” , we expand o,d,t can be inferred with a variety of probability distributions. However, given a short time dimension of our panel data (merely 12 years long), we limit Ωo,d,t to follow a simple p order Autoregressive (AR) process. In our estimation, we use the Hyndman–Khandakar algorithm to determine the order of AR based on Akaike Information Criterion—i.e., with the smallest AIC value [o,d,t can be written as,s are autoregressive terms with p order.In principle, the stochastic process of ΩIC value . With thHow well can our FTG models Eqs  and 7 exAs FTG models treat panel data as time-series stratified by dyad flows, the number of parameters thus grows substantially. A consequence of this large parameter set is that, whilst FTG will have a stronger explanatory power than FE in the training set, it might translate into a weaker predictive power . In our cross-validation, we seek to examine the extent to which FTG models are prone to over-fitting. Specifically, we analyze how the testing errors of FTG models may change with respect to the length of time-series. To conduct such an analysis, we apply a cross-validation procedure known as “rolling forecasting origin” .The estimated climate impact on forced migration is small and insignificant in both FE and FTG models. This finding is in stark contrast to the recent evidence suggesting that droughts in Western Asia played a significant role in driving asylum-related migration to Europe during 2011–2015 . Such a The most striking pattern in The most striking finding from Given the predominant role that the flow fixed-effects model has played in the field of modelling and forecasting migration flows, it is critical to understand why its performance worsens when the panel data grow in length. A plausible explanation is that the FE model can capture only spatial, but not temporal, variation in migration flows . This caThe stochastic component, namely the autoregressive (AR) term in Overall, the model comparisons presented above suggest that FTG models are preferable for two key reasons. First, this class of model can account for heterogeneity in migration responses to time-varying factors, which is pervasive see . Second,However, it is important to note that the performances of FTG models are highly dependent on the length of flow time-series data; the data needs to be sufficiently long relative to the number of parameters, in order for FTG models to make reliable inferences and predictions. Another important point is that, despite their better performances relative to FE models, FTG models are far from being perfect. As can be seen from As spatial-temporal panel data on human migration become increasingly available, the techniques to fit gravity models have evolved significantly during the last decade, from simple cross-sectional analysis of spatial patterns to more advanced Fixed-Effects (FE) models. The latter model class is designed to infer migration responses to not only spatial, but also temporal variations in economic, geopolitical, environmental factors, among others. However, a recent study demonstrated that such approach failed to explain, and hence to predict, temporal dynamics, it can merely describe spatial patterns of international migration .In this article, we derived a Flow–Specific Temporal Gravity (FTG) model that is theoretically informed by the random utility framework. Using EUROSTAT asylum statistics together with climate, conflict, and economic indicators, we demonstrated how the FTG model can account for heterogeneous migration behavior. We also assessed and compared models’ performances at various lengths of training data. The results suggest that, as flow time-series data lengthens, FTG models’ predictions can be increasingly accurate, whereas FE models become less predictive. However, we would like to highlight a key limitation in our analysis, and discussing how our results might depend on this limitation.The empirical gravity models specified in our analysis Eqs , 6 and 7“Data Hungriness” is an apparent shortcoming of FTG models. As the length of time-series flow data are generally limited, building more complex FTG models is therefore challenging. To conclude, we would like to discuss a few options that might potentially ease such a challenge.While it takes time for migration data to grow in length, increasing the frequency of analysis may permit FTG models to include a richer set of predictors and/or their lags. For example, weekly asylum statistics are now being compiled by EUROSTAT which have already been used to model refugee migration to Europe . HoweverAnother option to ease the constraints posed by short time-series could be to appropriately group the data, while keeping it at a low frequency . For exao,d,t in Finally, given that the distributions of flow-specific parameter estimates (as shown in


Separated by half a continent and over 1800 years, Akhenaten, the “Heretic Pharaoh” of Egypt, and Khingila, “The God-King” of the Alchon Huns, had a great deal in common. Both rulers laid claim to divinity, labeling themselves as gods amongst men, and both are represented in their official imagery with unusually shaped skulls consistent in appearance with artificial cranial deformation (ACD) performed upon them soon after birth. This article compares the evidence - including the KV55 mummy, likely the remains of Akhenaten himself - between the two God-Kings and determines that Khingila almost certainly possessed an annular erect ACD consistent with the wider Hun culture. Akhenaten’s ACD in his state-sponsored imagery was likely solely an artistic choice meant to emphasize his oneness with the divine. In both men, their represented ACD was ultimately intended to solidify their power through two different avenues. For Khingila, it was to emphasize a common ethnic and cultural heritage with his subjects. For Akhenaten, it was meant to set the pharaoh even further apart from the rest of humanity. Artificial cranial deformation (ACD), the molding of neonatal skulls into permanent shapes, has been used in a wide variety of human cultures from the dawn of prehistory  to the mACD has often been seen as a mark of intelligence and leadership granting one the right to rule, so much so that the term "heads of state" may originate from the use of ACD in medieval European nobility . This paArtificial cranial deformationth century France, sub-Saharan Africa, and many others. Some researchers even theorize that the term “heads of state” comes from the practice of infant ACD among medieval European nobility [ACD is one of the oldest practices of body modification in existence, with the earliest known examples being two Neanderthal specimens from approximately 45,000 years ago . Only ponobility .ACD is done for a variety of motives - including ethnic and cultural identity , the disbandeau head wrap of medieval France [Throughout history, there have been a number of techniques to accomplish ACD in a newborn. The most widespread is the use of tightly-wrapped fabrics and bandages , possibll France .ACD can be broadly grouped into two general categories. The first, annular ACD, produces a circumferential skull through constriction of the head with pressure bandages. The result is a “distinctive conical cranial vault” that can be further subdivided into oblique and erect forms . The secBoth of the rulers discussed in this article are represented in their official iconography with annular ACD. Akhenaten’s long, sloping skull  is more AkhenatenFrom 1353 to 1336 BCE, Egypt was ruled by “the most controversial and enigmatic of pharaohs”, the architect of a radical vision that “if it had survived, would have changed not just the history of ancient Egypt but, perhaps, the very future of humanity” [maat , Akhenaten declared that he was maat. In the Sun God’s realm, “truth no longer had an existence independent of the king’s actions: it was, by definition, whatever he wanted it to be” [Although previous pharaohs had grasped at divinity - Amenhotep III, Akhenaten’s father, famously declared that he had been conceived when the god Amun-Re visited his mother in the palace one night  - Akhenat to be” . Even tht to be” . The efft to be” .The reign of Akhenaten ended in its seventeenth year with the pharaoh’s death, and his son Tutankhamun (commonly known to the modern world as King Tut) took the throne. Tutankhamun was unable to replicate the achievements of his father and died at a young age soon afterward. The royal line of Egypt’s Eighteenth Dynasty died with him, and Akhenaten’s successors quickly took steps to eliminate all traces of the “heretic” pharaoh and his strange religion . They weFor our purposes, the unique iconography representing Akhenaten must be addressed. As previously established, the pharaoh’s unique representation portrayed him with both masculine and feminine features. In the past, researchers have theorized several etiologies for this, including a symbolic representation associating him with the creator Sun God , an aromth century, researchers proposed that Akhenaten may have suffered from a form of hydrocephalus responsible for his appearance in the artwork of the time. His daughters, depicted in the same artistic style, may have had their heads artificially deformed in imitation of their divine father [While evidence for ACD in ancient Egypt is virtually non-existent , the Eige father . It likee father . As the e father , AkhenatWhile this is an intriguing theory, the evidence currently available to us suggests that it is highly unlikely. In 1907, a “small, single-chambered roughly-hewn rock tomb” was discovered by Edward R. Ayrton in The Valley of the Kings . Within One of the most interesting aspects of the KV55 mummy is its skull, shown in Figure Modern CT imaging has supported Harrison’s findings. In a 2010 paper, researchers found that the KV55 skull had a cephalic index of 81.0 . TutankhAlthough ACD was relatively common in the ancient Middle East, ACD within Egypt itself was a relative rarity. The oldest confirmed Egyptian skull to display ACD dates to the sixth century, some 1900 years after Akhenaten’s reign . As we hKhingilaDeva Shahi Khingila, “God-King Khingila” [While a wealth of information and evidence has survived regarding Akhenaten - including his remains, if the theories about the KV55 mummy are true - the physical evidence of Khingila, who lived over 1800 years closer to the present day, is far more lacking. Despite his status as one of the early rulers of the Alchon Huns , and thus the ruler of a vast territory that included much of modern Northwest India , even thhingila” , one of hingila” .As a subgroup of the larger Hun culture, the Alchon Huns acted as a melting pot and crossroads between India, Iran, and Central Asia during much of the fifth and sixth centuries. Much like Khingila himself, they did not leave many written sources behind, and “coins and inscriptions are our main sources of information” . Their cth and 6th centuries CE, the Huns brought annular ACD from the Eurasian steppes to central Europe. In Late Antiquity Bulgaria, a region under the Hun’s control during this period, skeletal remains from “almost all age groups”, from toddlers to the elderly, display evidence of annular ACD, something that was not present amongst the population before Hun tribes came to the area [The practice of annular ACD was extremely widespread among the greater Hun cultural group, of which the Alchon Huns were only a small offshoot . As the the area . Populatthe area . The infthe area  ironicalthe area .While the physical evidence for Khingila is far more lacking than Akhenaten, it is almost certain that his iconography - displaying him with an annular ACD - is a true representation of his appearance. Not only was the annular ACD exceptionally common amongst the broader Hun sphere of influence , it was Ultimately, the difference between Akhenaten and Khingila comes down to the difference in their chosen artistic representations. This author theorizes that Akhenaten, as the prophet of a new religious faith, intended to set himself apart from the rest of humanity, and the bizarre ACD displayed in his official iconography was one of the ways the pharaoh used to make himself appear both divine and otherworldly. It appears that Khingila portrayed himself with ACD precisely because he wished to establish a rapport with his subjects. As a proud Alchon Hun, his ACD likely created a sense of ethnic unity and belonging. While his remains have never been found, he did likely undergo annular ACD in the traditional context of the Huns; it is highly doubtful that he could have risen to such a high position otherwise. In this author's opinion, it was not Khingila’s proclaimed divinity that gave him ACD; it was his ACD that gave him a claim to divinity.