Abstract
Neurophysiology studies have identified neurons in the oculomotor system that remap their receptive fields (RFs) around the time of saccade, which has been thought to have a potentially important role in shaping perisaccadic visual perception (Melcher and Colby, 2008). However, conflicting reports exist, in which some indicate that these remapping neurons gain response to visual stimulus presented at the new location in the visual field displaced in parallel with the saccade vector in Lateral Intraparietal area (LIP, Duhamel et al., 1992) and Frontal Eye Field (FEF, Sommer and Wurtz, 2006) while other reports show those neurons shift their RFs towards the saccade target in a compressive and convergent manner in area V4 (Tolias et al, 2001), FEF (Zirnsak et al., 2012). More importantly, Sommer and Wurtz (2006) showed the remapping activity in FEF was linked to corollary discharge (CD) relayed from superior colliculus (SC) via mediodorsal thalamus (MD). Here, we model single neuron receptive field remapping with a neural model using known anatomical pathways between SC, MD, and FEF. Our model indicates that using basic anatomical connections between these areas with a generic inter-areal on-center off-surround structure, is sufficient to yield RF remapping observed in single-cell studies, while compressive patterns of activity follows naturally from such architecture and its temporal dynamics. More specifically, the spatiotemporal interaction between the corollary discharge and signals that indicate fixation within the thalamo-cortical loop of the model plays a key role in achieving RF remapping. The model suggests reciprocal thalamo-cortical connections effectively stretch the RF size, thus allowing remapping to occur in cells over longer cortical distances. Since the model has a very basic functional architecture, we suggest it can be generalized to other cortical areas that have similar connectivity with SC and thalamus.
Meeting abstract presented at VSS 2013