Hand Shape Representations in the XXXX Posterior Parietal Cortex.

@entity1 @entity550
@entity1 shape their hands to grasp, manipulate objects, and to communicate. From nonhuman primate studies, we know that visual and motor properties for grasps can be derived from cells in the @entity550 ( @entity550 ). Are non-grasp-related hand shapes in @entity1 represented similarly? Here we show for the first time how single neurons in the @entity550 of @entity1 are selective for particular imagined hand shapes independent of graspable objects. We find that motor imagery to shape the hand can be successfully decoded from the @entity550 by implementing a version of the popular Rock-Paper-Scissors game and its extension Rock-Paper-Scissors-Lizard-Spock. By simultaneous presentation of visual and auditory cues, we can discriminate motor imagery from visual information and show differences in auditory and visual information processing in the @entity550 . These results also demonstrate that neural signals from @entity1 @entity550 can be used to drive a dexterous cortical neuroprosthesis. SIGNIFICANCE STATEMENT: This study shows for the first time hand-shape decoding from @entity1 @entity550 . Unlike nonhuman primate studies in which the visual stimuli are the objects to be grasped, the visually cued hand shapes that we use are independent of the stimuli. Furthermore, we can show that distinct neuronal populations are activated for the visual cue and the imagined hand shape. Additionally we found that auditory and visual stimuli that cue the same hand shape are processed differently in @entity550 . Early on in a trial, only the visual stimuli and not the auditory stimuli can be decoded. During the later stages of a trial, the motor imagery for a particular hand shape can be decoded for both modalities.
