title: Processing of Positive and Negative Feedback in Patients with Cerebellar Lesions.
abstract: It is well accepted that the cerebellum plays a crucial role in the prediction of the sensory consequences of movements. Recent findings of altered error processing in patients with selective cerebellar lesions led to the hypothesis that feedback processing and feedback-based learning might be affected by cerebellar damage as well. Thus, the present study investigated learning from and processing of positive and negative feedback in 12 patients with selective cerebellar lesions and healthy control subjects. Participants performed a monetary feedback learning task. The processing of positive and negative feedback was assessed by means of event-related potentials (ERPs) during the learning task and during a separate task in which the frequencies of positive and negative feedback were balanced. Patients did not show a general learning deficit compared to controls. Relative to the control group, however, patients with cerebellar lesions showed significantly higher ERP difference wave amplitudes (rewards-losses) in a time window between 250 and 450 ms after feedback presentation, possibly indicating impaired outcome prediction. The analysis of the original waveforms suggested that patients and controls primarily differed in their pattern of feedback-related negativity and P300 amplitudes. Our results add to recent findings on altered performance monitoring associated with cerebellar damage and demonstrate, for the first time, alterations of feedback processing in patients with cerebellar damage. Unaffected learning performance appears to suggest that chronic cerebellar lesions can be compensated in behaviour.
authors.affiliation: Institute of Cognitive Neuroscience, Department of Neuropsychology, Ruhr University Bochum, Universitaetsstrasse 150, 44801, Bochum, Germany. Martina.Rustemeier@rub.de.|Department of Psychosomatic Medicine and Psychotherapy, LWL University Hospital Bochum, Ruhr University Bochum, Alexandrinenstrasse 1-3, 44791, Bochum, Germany. Martina.Rustemeier@rub.de.
authors.forename: Martina
authors.initials: M
authors.lastname: Rustemeier
authors.affiliation: Department of Neurology, Klinikum Dortmund, Beurhausstrasse 40, 44137, Dortmund, Germany.
authors.forename: Benno
authors.initials: B
authors.lastname: Koch
authors.affiliation: Department of Neurology, Klinikum Dortmund, Beurhausstrasse 40, 44137, Dortmund, Germany.
authors.forename: Michael
authors.initials: M
authors.lastname: Schwarz
authors.affiliation: Institute of Experimental Psychology, Heinrich Heine University Duesseldorf, Universitaetsstrasse 1, 40225, Duesseldorf, Germany.
authors.forename: Christian
authors.initials: C
authors.lastname: Bellebaum
mesh_terms: D000328:Adult; D000368:Aged; D001245:Association Learning / Q000502:physiology; D002531:Cerebellum / Q000000981:diagnostic imaging / Q000503:physiopathology*; D004569:Electroencephalography; D005071:Evoked Potentials; D005260:Female; D000068156:Formative Feedback; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D011337:Probability Learning; D014163:Transfer, Psychology / Q000502:physiology; D014796:Visual Perception / Q000502:physiology
keywords: Cerebellum; ERPs; Feedback learning; Feedback processing