Kent, J. 1 , Matthews, S. 1 , Bolbecker, A. 1, 2 , Rass, O. 1 , Klaunig, M. 2 , Jones, M. 1 , O'Donnell, B. 1, 2, 3 & Hetrick, W. 1, 2, 3
1 Department of Psychological and Brain Sciences, Indiana University, Bloomington, IN, USA
2 Larue D. Carter Memorial Hospital, Indianapolis, IN, USA
3 Department of Psychiatry, Indiana University School of Medicine, Indianapolis, IN, USA
Although the role of the cerebellum in motor coordination has long been appreciated, only recently has its role in cognitive processes been explored. Theoretical models of psychopathology identify the cerebellum as a critical node in a coordinative network regulating cognition. We tested the hypothesis that performance on a cerebellar-dependent associative learning task (delay eyeblink conditioning) would be correlated with semantic fluency performance in healthy individuals (n=10) but not in schizophrenic (n=8) and bipolar (n=11) participants, where cerebellar anomalies have been reported. Subjects completed delay eyeblink conditioning (EBC) and a semantic fluency task. During EBC, an airpuff that elicits an unconditioned blink response is repeatedly paired with a tone. Subjects develop a conditioned blink response (CR) to the tone that precedes the airpuff. In the semantic fluency task, subjects name exemplars from the “animal” category for two minutes. In healthy participants, but not in schizophrenia or bipolar participants, the number of items generated on the semantic fluency task correlated with CR timing (r(9)=-0.71, p=0.02). This relationship between performances on a cerebellar-mediated task (delay EBC) and semantic fluency in healthy participants supports the hypothesis that the cerebellum is involved in the coordination of cognitive processes in individuals with intact cerebella.