Procedural learning impairments identified via predictive saccades in chronic traumatic brain injury
Cognitive and Behavioral Neurology
oculomotor function; predictive saccades; reflexive guided saccades; Traumatic brain injury
Objective: To characterize integrity of fronto-striatal circuitry in chronic traumatic brain injury (TBI). Background: Due to both direct and indirect effects, TBI is hypothesized to affect frontal and striatal function. On the basis of elegant animal, lesion, and neuroimaging literatures, oculomotor testing can provide a useful tool for in vivo assessments of neurophysiologic function. The predictive saccade paradigm in oculomotor function is well established to provide assessment of this fronto-striatal circuit. Methods: Sixty patients with a history of chronic TBI completed 2 specific tests of oculomotor function, including a test of reflexive visually guided saccades to assess basic oculomotor function and a predictive saccade test to assess procedural learning. Results: TBI (mild and moderate/severe) was associated with a decrease in rates of procedural learning, with degree of impairment increasing with injury severity. This was observed as a decrease in the proportion of anticipatory saccades (primary measure of learning). Conclusions: This abnormal oculomotor performance supports the hypothesis that TBI results in chronic impairment of frontal-striatal functions proportionally to injury severity and demonstrate that oculomotor testing is sensitive to all severities of closed-head injury. Copyright © 2010 by Lippincott Williams & Wilkins.
Kraus, M., Little, D., Wojtowicz, S., & Sweeney, J. (2010). Procedural learning impairments identified via predictive saccades in chronic traumatic brain injury. Cognitive and Behavioral Neurology, 23 (4). http://dx.doi.org/10.1097/WNN.0b013e3181cefe2e