Abstract
During natural vision, the positions of stationary objects change on the retina with each eye movement. However, our perception of the visual scene remains stable. It is thought that this stability arises, at least in part, by the visual system’s ability to update spatial information. It has been previously shown that neurons in the lateral intraparietal area (LIP) predictively respond to the presence of objects in their future receptive fields around the time of a saccade (Duhamel et al., 1992). However, it is unknown whether this remapping contains information about the priority of the objects or just about their location in space. Further, it is not known whether information about all objects is remapped or whether only information about an attended object is remapped. To investigate this, two animals were trained to perform a task in which they searched for a reward-loaded target among 10 objects consisting of targets and distractors. After the stimuli appeared, the subjects were free to move their eyes to find the reward-loaded target. Stimuli were spaced such that when looking at one stimulus, another was in the LIP neuron's receptive field. Responses of LIP neurons were significantly higher to targets compared to distracters. During fixation, the latency of this significant difference was at least 70 ms. When brought into the receptive field by a saccade, the latency of this difference appeared as quickly as 20 ms, showing a predictive remapping of stimulus priority. This short latency difference appeared across the entire visual field and was independent of eye movement direction and location. We suggest that the attentional priority across the entire visual field starts to be transferred to the future receptive field of neurons just before the initiation of the saccade and is significantly distinguishable shortly after the end of the saccade.
Meeting abstract presented at VSS 2012