title: The cerebellum is involved in reward-based reversal learning.
abstract: The cerebellum has recently been discussed in terms of a possible involvement in reward-based associative learning. To clarify the cerebellar contribution, eight patients with focal vascular lesions of the cerebellum and a group of 24 healthy subjects matched for age and IQ were compared on a range of different probabilistic outcome-based associative learning tasks, assessing acquisition, reversal, cognitive transfer, and generalization as well as the effect of reward magnitude. Cerebellar patients showed intact acquisition of stimulus contingencies, while reward-based reversal learning was significantly impaired. In addition, the patients showed slower acquisition of new stimulus contingencies in a second reward-based learning task, which might reflect reduced carry-over effects. Reward magnitude affected learning only during initial acquisition, with better learning on trials with high rewards in patients and control subjects. Overall, the findings suggest that the cerebellum is implicated in reversal learning as a dissociable component of reward-based learning.
authors.affiliation: Institute of Cognitive Neuroscience, Department of Neuropsychology, Faculty of Psychology, Ruhr-University of Bochum, 44780 Bochum, Germany. patrizia.thoma@rub.de
authors.forename: Patrizia
authors.initials: P
authors.lastname: Thoma
authors.forename: Christian
authors.initials: C
authors.lastname: Bellebaum
authors.forename: Benno
authors.initials: B
authors.lastname: Koch
authors.forename: Michael
authors.initials: M
authors.lastname: Schwarz
authors.forename: Irene
authors.initials: I
authors.lastname: Daum
mesh_terms: D001245:Association Learning / Q000502:physiology; D001921:Brain / Q000502:physiology; D002526:Cerebellar Diseases / Q000503:physiopathology*; D002531:Cerebellum / Q000502:physiology*; D002536:Cerebral Arteries / Q000502:physiology; D002755:Choice Behavior; D003071:Cognition; D055253:Color Vision; D005684:Gait; D006801:Humans; D008279:Magnetic Resonance Imaging; D008875:Middle Aged; D012016:Reference Values; D012054:Reinforcement, Psychology; D012193:Reversal Learning / Q000502:physiology*; D012201:Reward; D013060:Speech / Q000502:physiology