Contextual modulation of primary visual cortex by temporal predictability during motion extrapolation

Abstract

ABSTRACTPredicting future events is a fundamental cognitive ability which often depends on the volatility of the environment. Previous studies on apparent motion reported that when the brain is confronted with low levels of predictability, activity in low-level sensory areas is increased, including primary visual cortex. However, other studies on temporal predictability reported opposite effects potentially due to the influence of attention. It remains unclear, however, how temporal predictability modulates brain responses in a more ecologically valid real motion paradigm. Our study investigated whether motion extrapolation in high and low predictable contexts would differently modulate fMRI-responses in subject-specific primary visual cortex during visible and partially occluded stimulation. To this end, participants performed a modified version of the interception paradigm in visible and occluded phases, in which they observed a stimulus moving horizontally, then vertically at two different velocities. They were instructed to press when and where the stimulus would reach a given point-of-contact. In high predictable context, the velocity was identical during horizontal and vertical (occluded) movement; whereas, in low predictable context, the velocity could change during the vertical trajectory. MVPA results revealed accuracies above chance for all classification analyses carried out with low and highly predictable context data. Moreover, trial-history analysis showed that a change in trial type (constant velocity after change in velocity and vice versa) increased BOLD-responses in V1. This pattern of results suggests motion extrapolation can enhance activity in primary visual cortex, regardless of trial-specific predictability, but it is affected by recent trial history.Highlights* Ignoring trial history high and low temporal predictability similarly enhance response in V1* In recent trial-history analysis, low temporal predictability enhanced responses in V1 compared to high temporal predictability* Shared regions inside primary visual cortex encode visible and partially occluded information