The role of prediction in eye movement control

11. Januar 2012

When we move, a signal is sent to the cortical motor areas that ultimately control motor neurons. This causal motor signal is different from the signal that informs other brain areas that a movement has been made. Such information about self-movement does not cause movement but relays the change in body position to the rest of the brain. In this talk, I will present work on the role of such self-movement information in perception and action. By enabling a prediction of the sensory consequences of movement, self-movement information is used to guide accurate sequences of saccades. It is generated at a relatively low level and represents accurate saccade metrics. Self-movement information also plays a role on longer time scales, such as in saccadic adaptation. Adaptation is the progressive modification of saccade amplitude in response to targeting errors. The error signal driving adaptation seems to depend on an accurate prediction of the sensory consequences of the saccade – a prediction based on self-movement information. Finally, self-movement information is involved in visual perception. Although small trans-saccadic displacements are notoriously difficult to report, under certain conditions they can reveal the use of accurate self-movement information to compare pre- and post-saccadic images. Such a mechanism is fundamental to visual stability.