Contribution of signals downstream from adaptation to saccade programming.

Information about ongoing behavior is necessary for stable perception and subsequent motor planning. Although many recurrent networks are known in the motor systems, the pathways that transmit the signals for internal monitoring of behavior are not specified. The present study reports that the pathways originating from sites downstream of cerebellar adaptation provide internal signals that are used for subsequent eye-movement programming. When monkeys made two successive saccades toward the locations of previously flashed targets or initial fixation, the second saccade compensated for the adaptive changes in the primary saccade. The use of signals downstream from adaptation for saccade programming contrasts with recent findings that signals upstream from adaptation control the perceptual localization of visual stimuli presented around the time of saccade, suggesting that separate recurrent networks provide behavioral information for perception versus movement programming.