BCIwiki (bciwiki.com) — According to the California Institute of Technology, a study conducted by its team was uploaded to bioRxiv on 2026-09-16, with authors including THURSTON, M. J. and Andersen, R. A. The preprint has not been peer reviewed. It examines how the cortical grasping network represents hand configurations and object properties during grasp motor imagery in participants with tetraplegia.
Three participants with tetraplegia performed grasp motor imagery during imagined object manipulation. Researchers recorded neural activity from the supramarginal gyrus (SMG), anterior intraparietal cortex (AIP), motor cortex (MC), and primary somatosensory cortex (S1). All recorded regions represented the whole-hand configuration of imagined grasps during motor planning and imagined execution.
Grasp-related neural activity in each region also varied with context: motor planning versus imagined execution, and object presence versus absence. SMG and AIP represented object shape during motor planning. The posterior parietal cortex (PPC) simultaneously encoded grasp and object properties, largely through distinct neuronal subpopulations.
The authors suggest that the separability of these representations in higher cortical regions could support more stable grasp control through brain-machine interfaces (BMIs). This is an interpretation of the neural representation findings. The study describes activity during motor imagery and does not establish restored hand movement or improved robotic BMI grasp performance.