Neural Activity of Monkey Primary Visual Cortex During Visual Discrimination of Tens-of-milliseconds interval

Abstract

Timing is a fundamental process to represent and discriminate events such as visual motion. However, little is known about precise mechanisms of how tens-of-milliseconds interval, critical for perceiving visual motion (Burt and Sperling 1981), is timed in the mammalian brain (Mauk and Buonomano 2004). Here we show that the neurons of rhesus primary visual cortex (V1) are sensitive to the temporal interval of tens-of-milliseconds between two stationary visual stimuli that sequentially appeared, the first outside the classical receptive field and the second within the center of receptive field. We further show that while monkeys discriminated the temporal interval, V1 neurons showed two other activity components: one that varied with upcoming choice between interval alternatives with a choice probability that was as strong as reported for orientation discrimination (Nienborg and Cumming 2014), and another activity component in the form of LFP that was related to reward. These results indicate that V1 neurons are sensitive to tens-of-milliseconds interval and modulate their activity according to perceptual decision on temporal interval regardless of physical interval. These results suggest a new role of the center-surround interaction for interval timing and discrimination.