The early research on ‘joint cracking’ that led to the development of this model is described in chronological order, alongside how this research was misinterpreted, which gave rise to the model’s flaw. Of concern, the flaw in this model makes worrying predictions that could lead to dangerous clinical decisions. Understandably, these predictions have attracted criticism over the use of manipulation as a therapeutic intervention. A corrected model, first published by Evans and Breen more than 15 years ago, is then presented and explained. Unlike the flawed model, this corrected model makes predictions in line with all available empirical data and additionally provides reassuring answers to critics. Many current definitions of manipulation have inherited the flaw from Sandoz’s model. Hence, a better, empirically derived definition, consistent with the corrected model, is now required.For manipulation, this paper addresses arguably the most fundamental question that can be asked about any therapeutic intervention:  If one attempts to read through the extensive literature that relates to manipulation , it becomes very noticeable that literally dozens of definitions and descriptions have been proposed . Often, a joint as the unit of manipulation, which deserves credit [thrust, for example, is used in the colloquial sense and is therefore inappropriate for a formal definition. Thrust is a reaction force  described quantitatively by Newton's third law of motion, which states that all forces between two objects exist in equal magnitude and opposite direction. Thrust is produced by a rocket’s engine when it rapidly expels the mass of its burned fuel in one direction, which simultaneously creates a reaction force that propels the rocket in the opposite direction. If the term must be used in the context of manipulation, thrust is technically the reaction force from the recipient to the practitioner, not the other way around.The composition of definitions listed in Table s credit . Beyond without exceeding the boundaries of anatomical integrity” [“without exceeding the anatomical limit” [within its anatomical limit” [is breached and tissues are damaged? Is this no longer a manipulation? This seems just too convenient and makes these definitions appear contrived. As would be the case with any other intervention , a manipulation that induces tissue damage or any other form of harm must still be a manipulation, irrespective of the (unintended) adverse outcomes.Several definitions include a clause stating that movements induced during a manipulation will stop short of causing tissue damage. Such clauses have been phrased as “tegrity” , “withoul limit” , or “witl limit” . Howeverphysiological range of motion, which suggests that there is at least one other non-physiological range of motion. To understand the origins and full meaning of this, and the other unusual terms within these definitions, we need to look closely at two important studies, which first requires a detour to post-war London.Some unusual terms have been used within definitions of manipulation, as can be seen in Table The first bioengineering study that looked at the relationship between joint movement and the phenomena of joint ‘cracking’ was published in 1947, by two physicians at the renowned St. Thomas’s Hospital Medical School in London. In their landmark study [To orientate ourselves with this important diagram, we can first observe that neither of the lines intersecting the vertical axis do so at zero. This is because the separation between the joint surfaces, represented by the vertical axis, was taken from a series of x-ray images (radiographs) that do not show articular cartilage; this particular MCP joint must have possessed approximately 1 mm of cartilage on each articular surface, causing the starting point to be just under 2 mm. The initiation of joint surface separation is described by the relatively horizontal, straight line that extends just above the horizontal axis until approximately 8 kg mass (80 N of force) is applied to the pulley system; the relatively flat slope (gradient) of this line shows that little joint surface separation is occurring as the applied force increases. Whatever is providing resistance until 8 kg is therefore fairly stiff. Suddenly, this line changes from being near horizontal to being near vertical, where Roston and Wheeler Haines explicitly indicate that this abrupt change is accompanied by an audible ‘crack’. After this crack, with increasing load the line returns to a near horizontal gradient once again, until it reaches a maximum separation of approximately 18 mm; a relatively large separation for an MCP joint! Collectively, the three phases of this ‘outward’ path describing increasing joint surface separation form something of a ‘Z’ shape. This Z-shaped path is extremely important, as we shall see later on. Attentive readers will also notice that a second path is drawn on the diagram reproduced in Fig. Roston and Wheeler Haines did not just provide the first example of the above diagram; they discussed the likely mechanism of the cracking phenomenon, and rightly implicated the intra-articular synovial fluid as crucial to this. However, it wasn’t until the late 1960s where a group of engineers from the University of Leeds, again in England, brought their considerable expertise and knowledge of human joint tribology to the phenomenon of joint cracking and produced the undisputed authoritative study on the subject . The metcavitation within synovial fluid was explicitly named as being responsible for the audible cracking phenomenon. Cavitation is the formation and activity of bubbles in fluid through the local reduction of pressure within fluid. During joint cracking, this pressure reduction is caused by the separation of the joint surfaces [refractory period first described by Roston and Wheeler Haines [The Leeds group also made a monumental step with regards to explaining the mechanism underlying the previously mysterious cracking event and the associated Z-shaped force–time path; for the first time, surfaces , which isurfaces . The redsurfaces  to form surfaces , 13; thesurfaces . The nassurfaces  Fig. 4)cavitatior Haines ; followiall important aspects of joint cracking and gave significant clues for the likely therapeutic mechanisms of action of manipulation. Unfortunately, few clinicians appear to have gained their knowledge first-hand from these two ground-breaking studies; instead, it seems that most did so second-hand through the interpretation of Raymond Sandoz, a French-Swiss chiropractor who published a handful of influential papers on manipulation [model of joint manipulation . Without doubt, this is the reason he felt the need to (conveniently) place his elastic barrier of resistance—sometimes referred to as the physiological barrier—in the way of such injury. Few have publicly questioned Sandoz’s model; instead, attempts have been made to patch it up [For those that learned Sandoz’s model during their professional training or have some investment in the ideas underlying his model, please don’t despair. Canny observers  have noch it up , or explch it up , 18–23, anatomical limit.Let’s take a closer look at Sandoz’s error and how it arose. Figure elastic barrier of resistance to the model. This was the term he used to represent the stiff resistance—known since 1947 to be caused by synovial fluid—that was seen during the first phase of the Z-shaped path , beyond which Sandoz referred to a paraphysiological space; the newly available addition to the joint’s range of motion (the third phase of the Z). Observant readers might already have spotted Sandoz’s mistake when looking at Fig. Sandoz’s blunder occurred when he added his th Figs. . Recall pure rotation about a stationary axis; it will only have been fulfilled by rotation plus some distraction. To test out the effect of a pure rotational motion, try fully flexing, extending or laterally bending an MCP joint by applying a force at the very the tip of one of your fingers, and you will only feel the silent resistance of joint capsules, ligaments and tendons.From knuckle-crackers, at this point there is typically a comment along the lines of, “hang on, I use joint rotation to crack my knuckles!” This may be true, but your habit will not have been satisfied by a elastic barrier?’ Undoubtedly, the resistance from synovial fluid that produces the first  phase of the Z-shaped path is very real and measurable, but where (and how) should one incorporate it onto the two-dimensional arc-shaped diagram of joint motion that was depicted in Fig. With Sandoz’s error now hopefully obvious, if we allow ourselves to retain his terminology the important question to now ask is, ‘where should he have placed his elastic barrier and the para-physiological space beyond. As guided by the partitioned synovial joint diagrams below the corrected arc-shaped model, the relationship between the centre of rotation (c) and the arbitrary fixed point (p) dictate both the correct location and extent of the para-physiological space. It now resides on top of the model, upon the upper border of the arc drawn by the rotational joint motion. While the joint surfaces are in contact, the para-physiological space has no area in this two-dimensional diagram . The space is therefore a potential space, akin to that of the pleura, only becoming real and apparent when the surfaces separate. The relative invisibility of this space is most likely why Sandoz missed its true location. Indeed, creating joint surface separation requires a force with a line of action perpendicular to the articular surfaces [The answer was published in 2006 . Figure surfaces ; in plaiwithin the joint’s physiological range of motion , moving further from its neutral position and towards its end range of rotation, this capacity diminishes towards zero. Therefore, articular surface separation  will be most efficiently attained when the joint is closest to its neutral configuration [grades of motion in individual joints [Apart from the fact that the corrected model Fig.  now demoon Table . When thguration . If clinl joints , the terelastic barrier provided deeper insights to the Z-shaped path recorded in the previous studies. The diagram that they created , and brd Mollan  imaged sall of these structures well, and Kawchuck and colleagues [All of the imaging studies discussed here have their methodological limitations. Repeating the high-frequency x-ray approach, used for the first time by Watson and Mollan  in the 1lleagues  conceivearticular surface separation (the indisputable precursor to cavitation) being achieved when a glenohumeral joint is placed in a position of ‘maximal laxity’ compared to end range positions [Despite the advances in knowledge over the past 15 years, there are some additional predictions made by the corrected model Table  that havositions , 36. Henwhat is it? In answering this question, the prevailing model of joint manipulation (of Sandoz) has been presented, alongside the research on the phenomenon of ‘joint cracking’ that led to its development. Research published since has also been covered in detail. Without exception, every single study on the subject shows that Sandoz’s model is fundamentally flawed. More concerning, the flaw in this model makes worrying predictions that could lead to dangerous clinical decisions. These predictions have been used (fairly) by observers to criticise the use of manipulation as a therapeutic intervention.For manipulation, this paper has addressed arguably the most fundamental question that can be asked about any therapeutic intervention: all available empirical data published before and since its conception. This corrected model also looks likely to fair well as new predictions are tested. It provides reassuring answers to critics, which should help with its acceptance by professional bodies and teaching institutions. Additionally, the corrected model should help clinicians to better judge the likely mechanisms of action, indications, and contraindications for the use of manipulation.Despite its flaw, Sandoz’s model has been highly influential. Retaining it is dangerous though, both for patients and for the reputation of manipulation as a therapeutic intervention. Moreover, retaining it in the knowledge of its flaw is unethical and will damage trust in the professional groups that use manipulation. Accordingly, Sandoz’s model should be removed from clinical training curricula with immediate effect. Thankfully, this removal will not leave a void. A corrected model, first published more than 15 years ago , makes pAt this point, it is worth re-reading the definitions of manipulation listed in Table The prevailing model of joint manipulation (of Sandoz) is fundamentally flawed and potentially dangerous. It should be universally replaced, with immediate effect, by a corrected model, which was first published more than 15 years ago.


Workplace health promotion programs (WHPPs) have shown to be effective in improving lifestyle behaviors of employees. Despite potential benefits for employees, participation rates are generally low. The aim of this study was to gain deeper insight into barriers and facilitators for participation in WHPPs prior to implementation according to employees.Peer-to-peer interviewing, a method derived from citizen science, was used to actively involve employees in the data collection. Employees working in the cleaning-, ICT- and facility-sector were trained to interview their co-workers. Interviews were recorded and transcribed verbatim. Thematic analysis was performed using the Consolidated Framework for Implementation Research (CFIR), complemented with the constructs ‘interpersonal factors’ and ‘intrapersonal factors’ from the social ecological model. Data were coded deductively and inductively, and rated by two researchers independently.Fourteen peer-interviewers conducted 62 peer-to-peer interviews. Main barriers for participation in WHPPs were an unsupportive organizational culture where lifestyle is not a common topic and programs that are not tailored to their needs. Support from peers and supervisors were facilitators. The availability of organizational resources, such as facilities and financial compensation, support participation.To enhance participation of employees in WHPPs it is recommended to take into account the barriers and facilitators identified in this study. For instance, employees should be involved in the development and implementation of WHPPS by the employer and their needs and available resources should be taken into account. This may lead to more successful implementation and higher participation rates in future WHPPs. The workplace is an ideal setting to promote a healthy lifestyle, among others as it can reach a large group of adults and because of existing infrastructures for interventions  barriers and facilitators are identified during the pre-implementation phase and (2) when employees are actively involved in the implementation and design of the program , was tailored to the Dutch context . Informed consent was obtained from all interviewees and the peer-interviewers.The integrated WHPP to be implemented exists of (1) a catalogue with health promoting activities on multiple levels  and multiple lifestyle themes  and (2) an implementation plan to support successful implementation  supervisors within the organization who informed employees about the study and asked them to participate as a peer-interviewer, or (2) a short presentation by one of the researchers (DS) on the aim and process of the peer-interviewing. Afterwards employees could sign up as a peer-interviewer. All employees who spoke and understood Dutch were eligible to participate as a peer-interviewer, with the exception of employees in a management position. None of the peer-interviewers had prior interview experience. Peer-interviewers were asked to interview five co-workers from their department who differed in age, sex, and job function, to create a heterogenic study population.All peer-interviewers followed an online training of 2 hours, provided by the researchers. In the training, they were educated on how to conduct an interview with a co-worker, were informed about how to obtain informed consent from their co-workers, practiced their interview skills with other peer-interviewers and received feedback from the researchers.The interviews were semi-structured and included three main questions: 1) about what employees think about when it comes to lifestyle; (2) about the current offer of WHPPs by their employer and whether and why they would participate or not and; (3) about the way they would like to be informed about WHPPs within their organization. To assist the peer-interviewers, they received cards with interview instructions, information about the study, main questions, sub-questions per main question and tips for further follow-up questions. Furthermore, they were instructed to listen carefully to their co-workers and adapt and personalize the follow-up questions when deemed appropriate. Additionally, age, sex, working hours, years of working at the organization and job type were asked. The main and sub-questions are depicted in Table  about whThe Consolidated Framework for Implementation Research (CFIR) was used as framework for the thematic analysis, complemented with two constructs of a social ecological model . Two steps of the analysis of qualitative data according to the CFIR were followed: 1) thematic coding and (2) rating. In the first step, the existing codebook of the CFIR with the additional constructs of the social ecological model was used to code the data  the valence of a construct, i.e. the positive or negative influence of the construct on participation and 2) the strength of this influence. Constructs could also be rated to have a neutral or mixed influence on participation .Within this domain the constructs ‘advantages’ (+ 2), ‘evidence strength and quality’ (+ 1), and ‘adaptability’ (+ 1) were facilitators for participation. Employees are more likely to participate in WHPPs when they are aware of the advantages of a program, in terms of health benefits including both physical- and social-health effects. Moreover, personal goals that can be achieved through participation in WHPPs are seen as advantages and might, therefore, facilitate participation. When there is evidence that a program can lead to increased health, employees indicate to be more willing to participate. This can be achieved by informing employees about the potential of proven effects. Employees also indicate that they would be more inclined to participate when programs are adapted to their age, their daily working schedule, or when there is sufficient choice in locations or types of sports: “‘Design quality’ (x) can both facilitate and hinder participation. Employees mention that a high quality WHPP, i.e. an evidence- or practice-based WHPP, can positively influence participation. The experienced quality can be improved by involvement of professionals or students. A mandatory program is a barrier for participation according to employees, whereas a program free of charge will support participation.‘COVID-19 pandemic’ (− 1) appeared to be a barrier for participation in WHPPs. Employees do not want to be at risk of becoming infected when they participate in a WHPP: “Peer-interviewer: And under which circumstances would you no longer participate in such activities? Employee: Well, that answer is actually quite simple, because of COVID-19. Because were it not for COVID-19, I would just participate”. .The And when your supervisor indicates that it [WHPP] is good for you. [⋯] Then you might also literally get people moving who otherwise might not have signed up for something of their own accord”. .The constructs ‘peer support’ (+ 1), ‘leadership regarding vitality’ (+ 1) and ‘networks and communication’ (+ 1), were identified as facilitators in this domain. Peer support can trigger employees to participate in WHPPs, as it brings an additional social component and co-workers can motivate each other. On the other hand, a small group of employees feels no need to engage in lifestyle related activities with their co-workers. For example, because they prefer to exercise on their own. With regard to the construct leadership, employees shared that information about the importance and possibilities of WHPPs provided by supervisors or managers can support their participation. This is also the case for supervisors who actively motivate and support their employees to participate: “Peer-interviewer: When would you participate in such an activity though? Employee: If I were informed a little bit more. What the concrete possibilities are within [the organization]”. . Additionally, employees mentioned they would like to be informed about WHPPs via presentations, information markets or other visible manners, posters, by phone, intranet, social media, newsletters, a personal approach and e-mail. However, an overload of information should be avoided, as this can lead to ambiguities or a lack of interest. Employees prefer active distribution of information, since it is not likely that they are going to look for information about WHPPs on their own initiative.Employees indicated that when communication about the WHP possibilities within the organization is clear and sufficient, there possibly is a lot of enthusiasm for it among their selves and co-workers: “I know that Tai Chi, yoga and office yoga, or the like, are organized during lunch breaks, and walks too, but it’s just very difficult to leave this workplace. You can’t leave the reception unoccupied. [⋯] Or you would have to arrange replacements, but I think that is a bit difficult. Maybe I do not have enough of a nine to five mentality and feel too much responsible to leave my workplace for something like that”. . Employees indicated that they would not participate in WHPPs when faced with an unsupportive organizational culture. For example when participation in WHPPs, especially during working hours, is not commonly accepted by co-workers: “Peer-interviewer: Look, in the past there also have been activities that were organized so to say, during the day, do you experience any obstacles to participate in such activities because it is during working hours? Because that's where you end up, isn’t it? Employee: Yes, that’s true, [⋯] that restraint is still there. [⋯] it’s not yet such a widely accepted, given”. . Additionally, in a culture where employees see their health and lifestyle as something private and not as something work-related, participation is hampered.A lack of ‘flexibility of work’ (− 2) and an unsupportive ‘organizational culture’ (− 2) were identified as barriers within the inner setting domain. Employees who are not able to leave their workplace during work time or have no flexibility to start or stop working later or sooner than scheduled, stated that it hampers their participation in WHPPs: “Peer-interviewer: What could the employer really do to make you participate? [⋯]. Employee: Maybe if you are allowed to participate during working hours? Then you are more inclined to participate. Besides that I wouldn’t know”. .The construct ‘available organizational resources’ (x) had a mixed rating. The availability of a financial compensation, for example for a gym or other sport will support participation. In contrast, high prices for healthy food in the company restaurant will hamper participation. According to employees, they are more likely to participate when the location of a WHPP is easy to reach. Hence, facilities such as a gym at the workplace are facilitators for participation with the lack of such facilities being a barrier. Another factor is time, the possibility to participate during working hours can be a facilitator, since a lack of time after working hours is a frequent barrier: “The construct ‘experiences’ (+ 2) was the only facilitator within the domain characteristics of individuals. Employees suggest that positive experiences with a WHPP, such as feeling healthier or having a good time, would be a reason to participate in other WHPPs as well.Look, if you don’t know about the existence of WHP activities, then you’re not going to use them either”. . Personal attributes such as injuries or a lack of energy, and a lack of personal resources such as time and financial resources also hinder participation. Family and friends, e.g. interpersonal characteristics, can motivate employees. However, the time and energy that is spent on a busy household hamper participation in WHPPs outside working hours. Also, employees indicate that they prioritize time spent with family over participation in WHPPs. Employees mention that they will not participate when a program does not fit their needs or when they do not enjoy it: “[⋯] When I wouldn’t participate in a challenge or something, if it isn’t really in my field of interests, yes that would be my answer. Actually it’s very simple”. . Employees who are already engaged in a healthy lifestyle, employees who do not recognize that their current lifestyle should be improved and employees who see their work as physical exercise, do not feel any need for participation in WHPPs: “Peer-interviewer: What would make you participate in such an activity? Employee: When it involves sports and exercise, I would not participate, because I get enough of those already. I mean through cleaning” .‘Knowledge about and familiarity with the intervention’ (− 2), ‘other personal attributes’ (− 1), ‘personal resources’ (− 1), ‘interpersonal characteristics’ (− 1), and ‘needs’ (− 1) were identified as barriers in this domain. With regard to knowledge and familiarity, it was emphasized that if employees were not aware of a program or when programs are unclear, they would not participate: “‘beliefs about the intervention’, ‘priority’ and ‘individual phase of change’ had a mixed rating (x) within this domain. Employees who believe that improving lifestyle is something you have to do yourself, and not something that your employer should facilitate, are less inclined to participate in WHPPs: “Peer-interviewer: How can your employer help you to improve your lifestyle? Employee: Well I don’t think that he [employer] can improve it [my lifestyle] that much, because it’s something that I have to do myself”. . The same goes for employees who indicate that they do not know how their employer could facilitate a healthy lifestyle of employees. On the other hand, employees with a positive attitude towards and belief in WHPPs, are more open to participation. When employees see the benefits and necessity of a WHPP, the construct priority is a facilitator. On the contrary, if employees are already actively engaged in a healthy lifestyle in their private time, their priority will not be to participate in WHPPs. Besides, most employees said to prioritize their work over lifestyle at the workplace, making priority a barrier as well. When employees are aware of the importance of a healthy lifestyle, it is more likely that they will participate. In contrast, if an employee is not aware of the importance of a healthy lifestyle, or when they do not recognize that there is a problem with their lifestyle, their individual phase of change hampers participation in WHPPs.The constructs The engagement of ‘champions’ (+ 1) was mentioned as a facilitator for participation. Enthusiastic employees might convince co-workers to participate and they can serve as a role model.From the perspective of employees, positive experiences and knowledge about advantages of participation were important facilitators for participation. The most important barriers for participation in WHPPs were an unsupportive organizational culture, a lack of knowledge about WHPPs and various individual characteristics, such as a lack of personal resources. Organizational resources could act as both a facilitator and a barrier for participation.Multiple other studies that identified barriers and/or facilitators according to employees were found with some similar findings (Nöhammer et al. The main strength of this study is the active participation of employees in collecting information about barriers and facilitators from their perspective. The peer-to-peer interview method is an innovative participatory approach (Tsui and Franzosa Due to the COVID-19 restrictions at the time of the study both the training and part of the interviews were online, which can be viewed as a limitation of our study. However, feedback about the online training from the peer-interviewers was positive and if there were any questions afterwards, they could easily reach the researchers. Some peer-interviewers used this opportunity. In online interviewing it might be more difficult to connect when body language is limited and poor network connections can interrupt the interviews (Moran and Caetano Another strength of this study was the use of the CFIR, this framework can be used across various contexts, including implementation of WHPPs (Molin et al. Possible selection bias should be taken into account as all organizations recognize the importance of WHP. Moreover, employees that applied as peer-interviewers might be the employees who also consider WHP to be of importance. However, not all interviewees had the same idea about the importance of WHP. This might indicate that there is less selection bias on the level of interviewees. The fact that organizations were recruited through the network of the research team is not expected to influence the results of the peer-to-peer interviews, as the peer-interviewers and interviewees were not involved in the decision of the organization to participate in this study.To increase participation in future WHPPs it is important that employees have a positive attitude towards WHP, are aware of the WHP offer at the workplace and know what a healthy lifestyle entails. To achieve this, clear and active communication, tailored to the target group, about possibilities and the importance of WHP, is key (Nöhammer et al. In conclusion, a supportive organizational culture and a positive individual attitude and knowledge seem necessary to increase participation of employees in WHPPs. This study showed that both individual factors and organizational factors play an important role in the participation of employees. Strategies to overcome barriers for participation will be incorporated in an implementation plan, to better implement the integrated WHPP. The effectiveness of the integrated approach, consisting of the catalogue and implementation plan, will be evaluated in a cluster randomized controlled trial. A process evaluation will provide more insight in the success of the implementation of the integrated WHPP. We recommend stakeholders, such as employers and occupational health and safety professionals, involved in the implementation of integrated WHPPs, to use this knowledge about barriers and facilitators for the implementation of future WHPPs.


Gibson: 40 years later” is based on the ECVP2019 symposium of the same name. Theaim of the symposium was to discuss and evaluate Gibson's legacy, 40 years after thepublication of his last book “The Ecological Approach to VisualPerception.” The symposium speakers were Bill Warren, Jim Todd, BrianRogers, Hal Sedgwick, Ken Nakayama, and Barbara Gillam. Five of the six speakershave written papers for this Special Issue, based on their presentations in theSymposium. A further four papers by Joe Lappin, Diederick Niehorster, GeoffreyBingham, and John Kennedy were also accepted for publication. Hal Sedgwick submitteda final paper for the Special Issue in which he summarizes the contribution of theArabic scholar, Ibn al-Haytham, who argued for the role of the ground plane inmaking judgements of distance and space perception—more than a thousand years beforeGibson!This James Jerome Gibson, commonly referred to as “J. J.”, was born in 1904 in theAmerican Midwest and grew up there. He attended Princeton University, graduating in1925, and then staying on to study the behaviorist approach to learning. Aftercompleting his PhD there in 1928, Gibson was hired by Smith College, anundergraduate college for women, where he stayed for 14 years. This was an importanttime for Gibson in several ways. In 1932, he married Eleanor Jack, a former studentof his. Eleanor Jack Gibson was determined to have a career in research herself, andshe went on to do graduate work at Yale with Clark Hull, a leading theorist oflearning. She received her PhD in 1938.“Principles ofGestalt Psychology,” which made available a detailed exposition ofGestalt theory and research in English. That book, as well as his conversations withKoffka, deeply influenced Gibson's thinking. Gibson never lost sight of Koffka'simportance and, many years later when one of us was studying with Gibson at Cornell,his research seminar devoted an entire semester to a careful reading and analysis ofKoffka's “Principles.”During the 1930s, J. J. Gibson was establishing a reputation based on his research inperception, particularly his discovery of the adaptation and aftereffects producedby prolonged exposure to figural forms such as tilt or curvature. Gibson's years atSmith also exposed him to Gestalt psychology. Kurt Koffka, one of the founders ofGestalt Psychology was at Smith. In 1935, Koffka published “Principles ofTopological Psychology,” which appeared in 1936. The book inspiredGibson's article: “A Theoretical Field-Analysis of Automobile-Driving,” publishedwith Laurence Crooks in 1938. This may have been Gibson's first effort to analyzethe information used to control visually-guided action.The Gestalt psychologist Fritz Heider and his wife were also at Smith, and theybecame personal friends of the Gibsons. It was Fritz Heider who introduced J. J.Gibson to the work of Kurt Lewin, and in particular, to his Following the entry of the U.S. into WWII, Gibson was recruited into the war effort.There was an urgent need to rapidly increase the number of airplane pilots in themilitary, but little understanding of how to select and to train them. The task ofimproving this effort was assigned to a group led by Gibson. They did research on awide range of related perceptual problems throughout the war years. It was instruggling with these very practical problems that Gibson gradually developed a newtheoretic approach to visual perception.Many of his new ideas appeared in print for the first time in 1947 in Gibson's finalreport to the army, summarizing his group's accomplishments.Following WWII, Gibson returned briefly to Smith, but in 1949 he was recruited tojoin the Department of Psychology at Cornell University, where he stayed for theremainder of his career.During this time, Eleanor Gibson, often referred to as “Jackie,” was continuing topursue her own career. The hurdles that all women in academia faced at that timewere only raised higher by being married to a male academic. Although Jackie Gibsonalready had a formidable body of published research by the time J. J. Gibson wasoffered a position at Cornell, there were rules against “nepotism,” which seemed tobe aimed entirely at the wives of male faculty, and this prevented her fromreceiving any faculty position at Cornell. Only in 1966, when J. J. received a grantthat allowed him to retire permanently from teaching, did Cornell give Jackie Gibsona faculty position, which she then occupied with great distinction for severaldecades more.After a few successful, but perhaps also stressful, collaborations, the Gibsonsdecided to go their separate ways in their research efforts, splitting the field ofvisual perception between them, with Jackie concentrating on learning anddevelopment. They had separate labs and each had their own students, but studentsoften attended seminars with both of them, and they continued to share and todevelop a common theoretical perspective.“The Perception of the Visual Field and theVisual World,” in which he developed his ideas into a coherent andcomprehensive theoretical approach.In 1950, J. J. Gibson brought out “The Senses Considered as Perceptual Systems” waspublished, in which Gibson extended his theoretical framework beyond vision to takein all of the perception.In 1966, “The Ecological Approach toVisual Perception,” which presents the theoretical developmentsproduced by 30 years of thinking and of research by Gibson and his students, as wellas other new work that he saw as related.And finally in 1979, he returned to vision in J. J. Gibson died of pancreatic cancer in December of the same year, 1979.“The Ecological Approach to VisualPerception.”The principal objective of both the symposium and this Special Issue was to evaluatethe legacy of the ideas contained in Gibson's 1979 book. This necessarily implies anevaluation of the idea of “direct” perception and why he rejected the role ofso-called higher-level processes of “inference” (Hermann von Helmholtz), “perceptualhypotheses” (Richard Gregory), “intelligent, thought-like processes” (Irv Rock). Inaddition, Gibson rejected the traditional assumption of insufficiency of theinformation reaching our senses in favor of the claim that there is a richness ofinformation in the natural, ecological world in which we have evolved and now live.As a consequence, our aim has been to provide answers to the question of whether,and how, these ideas have affected the way we study perception in the 40 years sincethe publication of stimuli we present to observers—from spatial frequencygratings, random dot patterns and simple line drawings to real-world images andchanging optic flow sequences. At the same time, there have been huge changes in themodels we use to test and complement our experimental findings, from David Marr'salgorithmic approach in the 1980's to the more recent convolutional neuralnetworks.It is worth remembering that there have been many changes over the last 40 years inboth the technologies that we use—from oscilloscopes to large-field displays,virtual reality and head-mounted devices—and in the characteristics of the“Light on solidshape”—clearly, way ahead of its time! The psychophysics section of theARVO meeting in 1980 was similarly dominated by papers and posters on low-levelaspects of vision—rods, cones and adaptation, spatial and temporal channels, andcolor vision. There was just a single paper session labelled “Perception”—which, weassume, was intended to include all other aspects of vision research includingillusions.The major areas of research in perception and vision science have also changed. Inthe program of the 1979 ECVP meeting, presentations on spatial and temporalprocessing, grating patterns, VEPs, color vision, eye movements, and physiologydominated. The notable exception to predominance of papers and posters on low-levelvision was Jan Koenderink's invited lecture entitled meaning of what the worldoffers—has crept into the way we think about perception.The topics of the sessions in this year's ECVP2022 meeting have little in common withthose of 40 years ago. They include “Scene Perception,” “Perception and Action,”“Multi-sensory Perception,” “Optic Flow,” and “Surface and Texture.” How much of theresearch reported at this year's conference has been influenced by J. J. Gibson'sideas? An impossible question to answer and, even if the research was influenced byGibson's ideas, it is not always appreciated or acknowledged. However, it is clearthat Gibson's ideas about surfaces, optic flow, information rather than stimuli, theclose link between perception and action, and the importance of studying perceptionin natural rather than impoverished environments, are now important themes ofcurrent research. Even Gibson's most controversial idea of “affordances”—thinkingabout perception as discovering the Perception might be an appropriate forum for anyone interestedin presenting an alternative view.As Editors of the Special Issue, we were delighted to receive all the submissionsbut, at the same time, we were a little disappointed that there were no submissionsfrom those who disagree with Gibson's approach and ideas. It is now too late toincorporate such views in our Special Issue but we hope that the Editorial sectionof


For families with children during the COVID-19 pandemic, it is crucial to explore how both youth and parents view their roles with regard to the shared caretaking of pets. We present findings from a U.S. based study of adolescents and parents regarding pet care responsibility. As part of a broader longitudinal study, we analyzed survey data from 567 pet-owning adolescents and a subset of 356 dog owning adolescents aged 10–17. We also conducted 31 in-depth interviews with parents of adolescents from the same study. Adolescents who reported more pet caretaking responsibilities were more likely to spend time with pets to cope with stress and to have improved family relationships during the COVID-19 pandemic. For dog owners only, increased levels of responsibility for the pet was significantly associated with a higher likelihood of identifying as a pet owner. Qualitative findings showcase the range of parental expectations and adolescent initiative around pet caretaking. Our study highlights the continued importance of pet companionship during the adolescent years as they develop their identities as responsible pet owners.For families with children during the COVID-19 pandemic, it is crucial to explore how both youth and parents view their roles with regard to the shared caretaking of pets. While most human–animal interaction studies examine adult or early childhood samples, our focus was on adolescent development. We present findings from a U.S. based mixed-method study of adolescent surveys and parent interviews regarding pet care responsibility. As part of an ongoing longitudinal study, we analyzed survey data from 567 pet-owning adolescents and a subset of 356 dog owning adolescents aged 10–17 as well as 31 in-depth interviews with parents of adolescents from the same study. Higher reported pet caretaking responsibilities was significantly associated with a preference for spending time with pets when stressed and improved family relationships during the COVID-19 pandemic for both pet owners and dog owners. For dog owners only, increased levels of responsibility for the pet was significantly associated with a higher likelihood of identifying as a pet owner. Qualitative findings showcase the range of parental expectations and adolescent initiative around pet caretaking. Our study highlights the continued importance of pet companionship during the adolescent years as they develop their identities as responsible pet owners. Approximately 70% of households in the US own a pet . In the Given the exponential increase in “pandemic pets”, the media reported on rising concerns related to post-pandemic pet abandonment ,7, conceAs reflected in the increased focus on the dynamics of pet ownership during the pandemic, understanding the role of pets in the family system is critical to supporting both human and animal health and well-being. In particular, for families with children, it is crucial to explore the types of interactions youth are having with their pets, and how both youth and parents view their role with regard to the care of the pet.The term “pet” has evolved over time to signify special animals that family members take care of not only physically but in quality of life . These eStudies are scarce that examine a child’s personal identification as a pet owner as opposed to a pet in the family that everyone owns. Fifield and Forsyth demonstrated that 63% of pet-owning families in their sample in New Zealand identified their early adolescent child as the sole owner of at least one pet . Those wAdolescence in particular is a fertile period when identity development takes place and identifying as a pet owner can be a core aspect of one’s social identity. Prior research revealed that early adolescents place pets almost as high as parents and friends as sources of validation and positive self-esteem . HoweverIn 2019, the U.K. Avon Longitudinal Study of Parents and Children (ALSPAC) found that, for children ages 0 to 18, ownership of all types of pets (other than cats and dogs) peaked at age 11 (80%) and decreased through adolescent years . HoweverStudies have showcased that the inclusion of a pet within a household and the responsibilities that go with it  strengthens the bond between child and animal, particularly when they have no siblings or if they are left home alone while parents work . BuildiPrior literature on pet caretaking within families with children is rather outdated. One seminal study in the U.K.  found thBoth parent and child attitudes appear to have a significant influence on the division of pet caretaking labor in their families. One study in the U.K. found that 94% of parents find pet caretaking skills important and beneficial to their children . On the The nature of attachment to pets and pet-related responsibilities shifted for many families at the beginning of the COVID-19 pandemic due to a seismic change in both daily routine and amount of time spent at home together. Early in lockdown, the majority (79.5%) of dog owners reported that the pandemic had changed their dog’s daily routine, including variations in the amount of time pets spent alone, decreased walking activity, and more frequent playtime . HoweverAs pets can be considered part of the nested family system, responsible and caring interactions with companion animals can be one measure of healthy family functioning . Prior sThe social lockdowns during the COVID-19 pandemic disrupted typical family interactions and processes, requiring a renegotiation of pet-related and non-pet-related responsibilities in the home. For instance, a study  found thadolescents cope with their stress by leaning on a pet for mental health benefits and whether the physical and mental act of taking care of pets is related to these coping behaviors. Much of the work on human-pet interactions has been conducted in pre-COVID-19 pandemic times, thus studies are emerging on how the social distancing period affected families with pets of different types. The following mixed-method research questions address our study aims:To fill in gaps in the field concerning adolescent pet responsibility, in-depth qualitative and mixed-method research is needed to obtain more detailed accounts of different family members’ perspectives of adolescents’ pet relationships and caretaking, e.g., ,42. GiveQuantitative:1a. From the adolescents’ perspective, how is companion pet responsibility related to family relationships during the COVID-19 pandemic, such as identifying as a pet owner and coping strategies when stressed?1b. Are there any differences between pet owning adolescents and dog owning adolescents?Qualitative:2a. How do parents socialize their adolescents to take care of their pets? What kinds of pet responsibilities do parents report adolescents take part in? How willingly are they participating in caretaking?2b. How do parents characterize the bonds between adolescents and their pets? Are pets thought of as family members or another household chore by adolescents?As part of a more extensive, longitudinal study of social and digital technology use among young adolescents, in Fall 2020 we recruited middle school students (grades 6–8) and high school students (grades 9–10) located in several Northeast United State school districts. School sites were selected based on school enrollment size, internet accessibility, and diverse racial/ethnic, and socioeconomic composition. Working with school principals and liaisons, we distributed informed consent/opt-out forms to parents . Parents received this information through paper flyers, school e-newsletters, parent email contact lists, parent-teacher organizations, and direct emails. The survey was distributed using Qualtrics during a dedicated in-person advisory period or health/wellness class, lasting up to 60 min. The dates of the survey were pre-scheduled with school administrators. Due to the COVID-19 pandemic and the remote learning period, survey data collection was spread out over the course of several days to capture all student cohorts. Some students were still fully remote and therefore completed the survey at home. The Qualtrics survey link was distributed to students in the Google Classroom platform, allowing any students absent during the survey period to participate from home. Due to state-wide restrictions, research staff was unable to enter the school sites in person. As a result, we relied on school teachers and staff to administer the survey. Study staff remained available via video conferencing to answer questions and troubleshoot technical issues. School sites received an honorarium along with gift card incentives for site coordinators. Adolescents that participated in the survey were entered into a gift card raffle for multiple 25$ gift certificates.Pet Owner Sample. Pet owning students (n = 567) were 55% female, 44% male, and 1% non-binary gender or missing, and represented diverse racially/ethnically backgrounds, with 62% identifying as White, 13% were Hispanic, 5% were American Indian, 4% were Black, 3% were Asian, 2% Middle Eastern, 6% multiracial, and 5% other/unknown race/ethnicity (Refer to Refer to . Sixty-tDog Owner Sample. Dog owning students (n = 356) were 55% female, 45% male, and represented diverse racially/ethnically backgrounds, with 66% identifying as White, 10% were Hispanic, 5% were American Indian, 3% were Black, 3% Middle Eastern, 2% were Asian, 5% multiracial, and 7% other/unknown race/ethnicity . If the adolescent indicated having any other type of pet, they were coded as a non-dog owner (0).Pet ownership was measured by a single item asking adolescents if they had a pet (Yes/No). Dog ownership was measured by a follow up question to pet ownership about the species of the pet. If the adolescent had more than one pet, they were asked to indicate the species of their favorite pet. Species response options included: “Little to none” (0) to “The most” (5). Adolescents were asked how much they agree with the following coping strategies to manage stress: spending time with a close friend, family, or pet(s); exercising/sports; spending time outdoors or in nature; being alone; using technology, such as watching favorite movies/TV shows, playing video games, social media, etc. Spending time with pets when stressed was measured using a single item on a 4-point scale ranging from “Mostly Disagree” (1) to “Mostly Agree” (4).Pet caretaking responsibility was measured using a single item asking adolescents how much responsibility they have caring for their pet at home on a 6-point scale ranging from “Having a pet” as one of their top 5 identities, they received a (1). If they did not select “Having a pet”, they received a (0).Pet owner identity was a single item that was part of a larger set of 10 items asking adolescents to check their top 5 identities  that are important to them in their life. If adolescents selected “A lot worse” (1) to “A lot better” (5).Family relationships during COVID-19 was measured with a single item asking adolescents to report how the quality of their family relationships had changed since the beginning of social distancing due to COVID-19. This item had a 5-point scale ranging from “Age. We calculated age using date of birth and date of survey completion.Gender. Participants were asked whether they identified as female, male, or non-binary/other.Free/reduced price lunch. As a proxy for socioeconomic status, we asked whether participants were eligible for free or reduced price lunch in their schools (Y/N). Those indicating Y are considered lower socioeconomic status compared to those who are not eligible.Parent interview participants were recruited from a subset of parents from the larger longitudinal study ,45 that n = 21) and 10 referred to sons. We confirmed the gender of the child by using the child’s self-report in the longitudinal study and the parent’s determination in the interview.Of the 31 interviews, 28 parents identified as mothers/female guardians, 2 as fathers/male guardians, and 1 as a non-binary parent/guardian. We confirmed demographic information from the longitudinal study at the start of the interview. 21 parents identified as White (68%), 2 Hispanic (6.5%), 2 Brazilian (6.5%), 1 Black (3%), 1 multiracial/ multiethnic (3%), and 4 unknown (13%). The majority (74%) of parents were dog owners, 23% owned cats, and 3% owned guinea pigs. Parents were asked to answer interview questions focusing on their middle school child. Most parents referred to daughters , child emotional attachment to their pet, coping and stress management, caretaking responsibilities, and social media and digital technology as it relates to the household pet. Because interviews were conducted during the height of the COVID-19 pandemic, parents were asked to discuss the impact of the COVID-19 pandemic on having or acquiring a pet, with an emphasis on their child’s remote learning experience. Parents were asked to focus on their middle school-aged child if they had more than one child and their child’s favorite pet if they had multiple pets. Interviews were conducted, recorded, and transcribed using Zoom.Quantitative. Regression analyses were used to explore the relationships between responsibility for a pet and identity, stress and family relationships within pet owners and within dog owners. Logistic regression was used to model identity and linear regression was used to model stress and family relationships. Regression models were first run separately for each outcome for pet owners (n = 567), excluding any students from the larger sample (N = 968) who were not pet owners. Next, regression models were run separately for each outcome for dog owners (n = 356), excluding students from the pet owners sample (N = 567) that did not own a dog. For each model, pet responsibility was the predictor variable and identity/family relationships/family relationships was the outcome or dependent variable. Each model controlled for age, calculated using student date of birth and date of survey completion, self-reported binary gender, and whether students received free or reduced price lunch at school. Students indicating a non-binary gender (n = 4) were categorized as missing, due to the low prevalence that could not be included in these analyses. For each regression model, missing data was handled using listwise deletion resulting in different sample sizes for each regression model. Sample sizes ranged from 295–538 for each model.Qualitative. Zoom interviews were recorded, transcribed, and verified by the research team, and imported into NVivo software (NVivo 12 Version: Plus) ... especially in his situation”. On the other hand, Terry felt it was unrealistic to introduce responsibilities to her children including her sixth-grade daughter, Amanda:Okay,  I envisioned me doing everything because I’m not gonna pretend like my eleven and an eight, nine year old are going to do anything… I knew it was going to be really big dog, so I knew walking the dog was out, like they were not going to be able to, he’s too big… If I say feed the dog, it takes two seconds to feed the dog, so, they’ll do that. They’ll pick up his toys… I think they’ve actually probably done more than I thought they were going to do.Overall, parents differed in their explicit expectations of their childrens’ petcare responsibilities prior to getting a pet. These differences appeared to be due, at least in part, to parents’ own attitudes and abilities to perform petcare, as well as their specific adolescent, family, and pet’s needs.Lessons surrounding petcare. Many parents of adolescents view pet caretaking as an opportunity for their children to learn responsibility and empathy for others. Catherine encouraged her tenth-grade son, Eddie, to try to understand and empathize with, Lenny, their cat’s, needs to understand his own role and responsibilities as a caretaker:You know, when Eddie got older, it was easier to talk about responsibilities and, when you ask him to do something… It’s so important to [say], “I asked you to feed Lenny. Like, I’m trusting that you’re going to go downstairs and feed him, because then, if you don’t, then he has no food.Similarly, Cecilia believes her children developed empathy “may a little bit earlier than if [they] didn’t have a dog. When her children first got the dog, her children learned that they “[had] to care for this tiny thing and… that’s something different, besides family, a person that you know something’s wrong and they feel bad”. Understanding the needs of pets may, evidently, teach children the importance of pet caretaking and the importance of their role in these responsibilities. At other times, parents may let their adolescents learn the importance of responsibility by letting them experience negative consequences of irresponsibility. When Nancy’s sixth and eighth grade daughters, Alexa and Hannah, refused to walk their puppy in the cold weather, they learned an important lesson about responsibility when the dog reacted negatively:It’s really important for [the dog] to go outside so that she doesn’t have these bad behaviors because you know, in puppy years. She’s still a very young dog and, and a young child requires attention and entertainment and exercise and all those things… When [the children] shirk that responsibility, seeing the consequences firsthand what happens when the 25 min walk is a lot better than them screaming for 25 min because the dog’s going crazy and has ruined another rug.COVID-19 and adolescent petcare expectations. In some families, the COVID-19 pandemic shifted expectations of petcare responsibilities for adolescents. Cecilia’s children, including her 13-year-old daughter, Natasha, were expected to take on additional petcare responsibilities while at home during remote learning:Yeah I mean we always said that they had to help, that the responsibility wasn’t just going to be solely my husband and mine. And then you know with them in school, obviously the responsibility falls more on the people that are home… They never really had that set schedule, they just kind of fell into that but now… the responsibility has fallen on them because they’re home with [the dog] during the day, more than we are.Additionally, many families acquired “pandemic pets” during the lockdown period early in the first months of the pandemic due to family members, including adolescents, spending unprecedented amounts of time at home. Stacy was initially inspired to get a dog to be a companion for her seventh-grade daughter, Marissa, during the pandemic. Given that Marissa was taking remote classes, Stacy anticipated that it would be a “great responsibility for her to take a walk after school with a dog”. Terry’s sixth-grade daughter, Amanda, also helped take care of their family’s dog acquired during the pandemic:Yeah, no, I think it’s so much better [raising a dog in a pandemic] because he doesn’t have to be in a crate all day. So, like two days a week he’s in the crate in the morning, and then the dog walker comes, and then he goes back in, and then my daughter comes home and lets him out and then that’s it, you know.The COVID-19 pandemic, in some instances, shifted the typical delegation of petcare responsibilities in families with adolescents.Pets as family members. Throughout the caretaking and bonding process, we found that adolescents often feel deeply connected to their pets, with several considering them to be members of the family (9 of 31). Prior to Lucia getting her seventh-grade daughter, Jada, a dog, Lucia taught her that “a dog is like a little baby” when explaining the importance of caretaking. In effect, Lucia feels that the dog is “really like [Jada’s] little daughter”, because she “cleans her butt’... changes the water, [and] puts her food”. Likewise, Nancy’s children, including her eighth-grade daughter, Hannah, felt their dog became “an instant family member” as their bond strengthened rather quickly. In other instances, pets seem to reciprocate a caretaking relationship with adolescents. Catherine observed that her tenth-grade son, Eddie, and his cat seem to treat one another as their “baby”:[The cat] cleans [my son] everyday like he cuffs his head and cleans his face and his and it lifts his hair into place… [My son] can hold him like a baby and he just lays on him—he doesn’t do that to any of us… I will never forget the first time, Eddie slept at my mom’s and the cat was miserable. And he came home the next day and laid on the ground and the cat like sniffed him like… People come in and they’re like, “What’s happening?” and I’m like, “Oh, the cats cleaning Eddie…” The cat thinks that Eddie is like his baby.In some families, adolescents overtly refer to pets as members of the family. Robin’s tenth-grade son “refers to [the cat] as a sibling versus as just a pet”. Further, some families consider pets to be indispensable parts of the family structure. After Anne’s children, including twin sixth-grade daughters, Catie and Caroline, got a dog, she felt that their family unit was complete:Nothing felt complete when we didn’t have a pet with the kids so I kind of thought of the dog in terms of kind of completing our family unit and he really has fulfilled that role. And often we kind of say, “what would we do if he wasn’t here?” Like, “how would we entertain ourselves?” That kind of thing.Challenges of pets in families. Though several parents report feeling like pets have become family members, not every pet acquired fits perfectly or naturally into the family structure. While close, family-like attachments between pets and adolescents seem to confer advantages, they also may present unique challenges. Anastasia’s eighth-grade daughter, Alison, bonded “instantly when she saw” the dog but, when it started showing signs of aggression and they had to relinquish it, the situation was “hard for [the] whole family”, especially Alison. In contrast, few families distinguish between pets and family members. Although Valerie’s family considers their three guinea pigs to create a “bit of family identity”, her eighth grade daughter, Julia, sees them as pets rather than friends.Adolescents volunteering to take care of pets. We found that adolescents perform a variety of pet caretaking responsibilities with a range of willingness, based on factors including their attitude towards the pet, their parents’ orders and expectations, and the established family dynamic. In some cases (15 of 31), adolescents are enthusiastically willing to help care for their pet. Janet’s thirteen-year-old son, Brian, takes initiative early in the morning:Sometimes, even before he wakes up before me. Like this morning, for instance, he woke up before I did, and he had already changed both the [cat’s] water and food. And he knows the exact measurements of food that he gives her from him watching me and my oldest daughter doing it, so he knows exactly the amount of scoop to put in her bowl…This morning was the second, maybe third, time he’s done that, without me being there watching.Anastatia’s eighth grade daughter, Alison, would “feed [the dog] whenever we needed to”, volunteering all of her free time to “do anything that would be needed in taking care of [the dog]”. Marcella’s eighth-grade son, Carson, enjoys the job of taking care of a pet and does not see it as an obligation:When he was little he loved to feed her and take her for a walk and even now, that’s like, I don’t even have to ask him… But I mean it’s one of those things that he doesn’t really think is a chore because it’s just a thing that he does every day like, “Oh, I have to take care of the animals”. It’s never something that I asked him to do.Some parents set firm initial expectations for pet caretaking responsibility for their adolescents which they follow closely and enthusiastically. Nancy’s family “run a tight ship” in terms of petcare responsibilities, though her children are “very good” about taking care of the dog, even asking their mother to “[try] to get another dog”.Blend of volunteering and assignment to take care of pets. While some adolescents demonstrated a personal, internal motivation to care for their pets, several adolescents completed a blend of voluntary tasks and assigned explicit assignments. Marco reports that, although his thirteen-year-old son, Lucas, has been assigned to feed the dogs breakfast and dinner, there are other petcare responsibilities that “he’s come to on his own. Unless it’s picking up poop or vomit, which he will absolutely not take part in even though he’s been asked”. Although Marcella’s eighth-grade son, Carson, volunteers to take care of the dog, he is solely responsible for the pet turtles:His turtles are his sole responsibility. I don’t take care of them at all. He feeds them, he cleans their tank, he plays with them. So, that’s his completely. The rest of the animals, he takes care of them at least 50% of the time. When my daughter’s home, they actually fight about who’s going to feed the dog or who’s going to walk the dog, which I think is fine.On the other hand, some families do not have explicit rules and, instead, follow an ad hoc approach to fulfilling pets’ needs. Marina’s children, including her eighth grade daughter, Mila, do not follow a regimented schedule to take care of their dog, Theo. Instead, Marina assigns Mila and the others tasks when they arise, while Mila also takes initiative to complete pet care tasks voluntarily:So if you know, like if, if I am tired and I’m like, “Mila, take Theo out”, you know stuff like that. And they’re fine with that, so yeah I don’t think there are rules. And, ok, Mila is kind of like on top of things in general. Like, she’s responsible and mature and so… Mila makes sure that he gets his, for example, his medicine. Like he has something monthly.Adolescents assigned to take care of pets. For other adolescents, pet caretaking is simply an obligation. Ellis’s children, including his fourteen-year-old daughter, Madeline, are assigned a chore chart to keep track of the children’s daily cat care responsibilities:Both of our girls, part of their chores are changing the cats’ water, changing their litter, feeding them every day, so they have a decent amount of their caretaking… I actually divide it for them. I made up a chore chart. So they have to do the cat litter together. My older child takes care of the changing of the water, and then they each do one feeding per day.Ana’s children, including her twelve-year-old daughter, Gabby, also must complete tasks on a chore chart to care for their two cats and four birds. Ana reports that she and her partner devised a system where “the chores change every month, so everybody will see, you know, the kitty litter, the food, the water”. As the oldest child, Gabby is also responsible for bathing and grooming the cat. Other adolescents are, simply, not fond of pet caretaking tasks that they find uninteresting or unsavory. Michelle’s seventh-grade daughter, Marissa, helps her clean the guinea pig cages every two weeks, though she does so “reluctantly”, seeing it is an unpleasant chore.Parent petcare responsibilities in families with adolescents. In few families with adolescents, petcare responsibilities fall primarily to the parents. Rachel, who has two children, including her seventh-grade, Jenna, is the primary caretaker of the dog with occasional assistance from her husband:Yeah, I mean if I’m not around my husband, happily, you know we’ll do the litter, feed her, but if I’m around she usually follows me. She has to take thyroid medication, so you know we drop a little pill, and all that stuff so, yeah, usually I’m the primary.Some parents who primarily care for the family pet wish their adolescents would contribute more to the caretaking. Trisha wishes that her children, ages 15, 13, and 12, would take more responsibility caring for their dog, Peanut:I would like them to even take more initiations of like, I hate to say it, but like to clean up after the pets. I mean you can’t just do it twice a year. So I think that would be the only thing [to improve upon]— for them to take more responsibility.Parent expectations of adolescent petcare. Several parents reported expecting to care for the pet prior to getting it, suspecting that their children would not be committed to their assigned or promised responsibilities. Cecilia was told at the shelter that “You know your kids are going to like this dog for five minutes and the responsibility is going to be yours”. Instead, she has been pleasantly surprised that the children have developed a strong bond with the dog, reporting that, “She’s the first thing that they say hi to when they come home, when they wake up, and the last thing that they say goodnight to them and they go to bed”.Other parents expected their children to put more effort towards petcare than they, in reality, put forth. Kim is a disappointed that her sixth grade son, Stephen, does not care to put more effort into providing for their dog’s emotional needs:And it’s not that they don’t love her they do, but they’re not devoted to her care, you know? It’s more of an, “oh she’s here and let’s pet her”… In terms of meeting her emotional needs, I don’t see that... She loves to have someone throw the ball, take her outside and throw the ball with her and they never do it.Similarly, Marina was surprised that her children, including her eighth-grade daughter, Mila, did not walk the dog as much as they had promised prior to acquiring one. Marina reports that she is “kind of new” to pet ownership with adolescents and did not anticipate that she would have to fulfill some of those responsibilities herself.Pet relationships and coping strategies. For some adolescents, pet caretaking and, subsequently, close pet relationships, have a positive impact on their lives. For Diana’s eighth-grade son, Andrew, the family’s two cats and one dog were important for providing entertainment and companionship during lockdown, effectively “boosting morale during the pandemic”. Similarly, Cecilia felt that the sense of responsibility her seventh-grade daughter, Natasha, felt towards their do, Sydney, led to a close, emotionally supportive adolescent-pet relationship:I think that having a pet has taught her responsibility. I think that you know emotionally like you know your pet… they sense when things are not okay. And she does. I don’t know that all pets are as intuitive as is she is, but she does. Like so she’ll sit with you, like last time we were going down the street and Abby came home early and I came in and I was like, “What are you doing?” And she was like, “I was just cuddling with Sydney”. It’s just a relationship that is so great for her it’s so great, for all of them.Pet versus dog-owning adolescents. For many dog-owning adolescents, their pet or pets are more of a source of emotional comfort as compared to other types of pets. For instance, Ben’s thirteen-year-old daughter, Stephanie, for instance, has a hard time making friends and is “a pretty guarded person” though she is “very affectionate” with their dog, Coco. Ben hopes, for his children, that the “comfort and feeling responsible, you know a responsible pet owner… can translate that confidence into the rest of their lives”. Jean reports that her twin sixth grade daughters, Angela and Samantha, began to “talk to [the dog] like she’s a human” during the pandemic lockdown. On the other hand, Valerie’s eighth grade daughter, Julia, does not feel emotionally supported by their guinea pigs. Julia feels if she, instead, had a dog, that she would “take to the dog and tell the dog [her] feelings” though “she wouldn’t do that with the guinea pig or the hamster”.Our mixed-methods findings highlight the unique importance of understanding the adolescent pet owning years from the perspectives of adolescents and their parents, particularly in the under-researched area of responsibility around pet caretaking, and how these aspects of the youth-pet relationship can intersect with family dynamics. Prior research ,14,15,16Quantitative results also demonstrated that family relationships improved during the pandemic for pet owning families where adolescents shared a larger burden of the pet caretaking responsibilities. Of course, this relationship is not causal, and it may be that families with stronger relationships are better able to facilitate youth engagement with pets. Past studies have suggested that a telltale sign of a healthy functioning household is how much members care and interact with their animals . Our quaMoreover, quantitative results indicated that spending time with pets was one of the top two types of strategies for coping when stressed, even more than spending time with family, technology use , exercising, or being outdoors/in nature. Particularly during the pandemic, interacting with a pet was a stress coping strategy that was still available to youth despite social restrictions. Similar to prior studies that described child pet caretaking as playing and cuddling, e.g., , the adoParents in our sample had a range of expectations about how their teens would take on the responsibilities of pet caretaking, and noted various levels of agreement and mismatch between their perceptions of the adolescent’s role in pet caretaking and the reality. Our interviews demonstrated that some parents had rather low expectations that their teens would step up and were pleasantly surprised; Other parents had higher hopes and were disappointed at their teens’ lack of motivation for pet caretaking. Adjusting expectations and flexibility to developmental changes for both the teenager and the pet may be an important feature of optimizing these relationships and warrants further exploration. Education on developmentally appropriate levels of pet caretaking and the types of responsibilities that are needed for different species of pets could be useful to families when planning the acquisition of a pet.The level of initiative from the teens themselves point to a major developmental shift from the childhood years that focus on play, e.g.,  to adoleMost prior work on child or adolescent interactions with their pet companions measure quality of relationship via an attachment framework, however, current measures of human–animal interaction and relationship quality do not typically take into account the fulfillment of pet caretaking responsibilities. Because parents/guardians often note that teaching responsibility is a direct reason for acquiring a pet, understanding how responsibility and caretaking links to youth perceptions of pets and family dynamics has high practical value. Although our current study does not explore pet attachment/bond distinct from responsibility and caretaking, future studies could further examine the unique and overlapping role that pet caretaking and attachment have on the quality of the adolescent-pet relationship.In addition to not exploring pet attachment, this study has several key limitations that could be addressed in future research. While the sample was relatively diverse, participants were recruited from a specific geographic area in the United States that is comprised primarily of urban and suburban residential locations. It may be that responsibility and caretaking of animals varies in more rural communities where families are more likely to have a combination of household pets and farm animals. There may have been a self-selection bias of particular types of parents who would agree to be interviewed about pet caretaking during the pandemic. Future research should also explore both youth and parent perceptions of responsibility longitudinally to assess any age related changes in these patterns and how those changes might impact family dynamics.We examined our research questions using a seldom used mixed-method approach in this field and we encourage other researchers to include multiple informants and methodologies to more deeply understand the phenomenon at hand. Our sample of adolescents ranged widely from tweens to teens (ages 10–17), thus subsequent work might want to further break down the nuances between early adolescent and later adolescent developmental changes in pet caretaking responsibilities and its effects on family dynamics.