Abstract
Although saccades change the distribution of neural activity throughout the visual system, visual perception and spatial attention are relatively unaffected by saccades. Studies of human observers have suggested that attentional topography in the brain is stablized across saccades by an active process that redirects attentional facilitation to the right neurons in retinotopic visual cortex. To characterize the specific neuronal mechanisms underlying this retargeting process we trained two monkeys to perform a novel behavioral task that required them to sustain attention while making guided saccades. Behavioral performance data indicate that monkeys, like humans, can sustain spatiotopic attention across saccades. Data recorded from neurons in extrastriate area V4 during task performance were used to access perisaccadic attentional dynamics. Specificially, we asked when attentional facilitation turns on or off relative to saccades and how attentional modulation changes depending on whether a saccade brings a neuron's receptive field (RF) into or out of the attended region. Our results indicate that for a substantial fraction of V4 neurons, attentional state changes begin ~100 ms before saccade onset, consistent with the timing of predictive attentional shifts in human observers measured psychophysically. In addition, although we found little evidence of classical, LIP-style spatial remapping in V4, there was a small anticipatory shift or skew of the RF in the 100ms immediately saccades detectable at the population level, although it is unclear of this effect corresponds to a shift towards the saccade endpoint or reflects a shift parallel to the saccade vector.
Meeting abstract presented at VSS 2018