Edmondson LR, Saal HP

In primary somatosensory cortex (S1) the representation of the hand is organized somatotopically, with neighboring locations on the hand represented by adjacent cortical neurons. However, the size of cortical regions is not proportional to that of their physical counterparts, and specific regions, such as the fingertips, can be magnified beyond their physical size. What leads to this size variance in cortex? To investigate the contribution of these factors, we adapt a computational model that has been successful in simulating the development of visual retinotopic maps to the sense of touch. We use a recently-developed large-scale simulation that reconstructs the responses of tactile afferent populations to create realistic peripheral response inputs. This model enables us to systematically vary the stimulus statistics and afferent density. Second, we use both principal component analysis and self-organising map algorithms to model and investigate the resulting somatosensory representation.