Prediction of sensorimotor contingencies generates saccadic omission

Area of Science:

• Neuroscience
• Visual Perception
• Sensorimotor Systems

Background:

• Rapid eye movements, known as saccades, occur frequently, yet we are unaware of the resulting visual motion.
• Previous theories proposed active or passive visual suppression during saccades.
• This study explores a novel theory: saccadic omission arises from habituation to predicted sensory consequences of actions.

Purpose of the Study:

• To investigate if habituation to predicted sensory consequences underlies saccadic omission.
• To experimentally induce and test the effects of novel, predictable intra-saccadic visual motion.
• To determine if the sensorimotor system habituates to recurring intra-saccadic visual motion.

Main Methods:

• Participants performed over 100 saccades across novel drifting gratings, visible only during saccades, to establish predictable contingencies.
• Contrast sensitivity for intra-saccadic motion was measured after repeated exposure.
• Tasks included saccade performance and fixation conditions, followed by a motion speed comparison task.

Main Results:

• Contrast sensitivity for intra-saccadic motion significantly declined after habituation trials.
• This reduction in sensitivity was specific to the saccade vector used during habituation.
• No sensitivity reduction was observed when similar tasks were performed during fixation.

Conclusions:

• The sensorimotor system selectively habituates to predictable, recurring intra-saccadic visual motion.
• This habituation mechanism contributes to visual stability by silencing predicted visual consequences of saccades.
• Findings suggest an efficient predictive mechanism underlying our seamless visual experience during movement.