title: The cerebellum and visual perceptual learning: evidence from a motion extrapolation task.
abstract: Visual perceptual learning is widely assumed to reflect plastic changes occurring along the cerebro-cortical visual pathways, including at the earliest stages of processing, though increasing evidence indicates that higher-level brain areas are also involved. Here we addressed the possibility that the cerebellum plays an important role in visual perceptual learning. Within the realm of motor control, the cerebellum supports learning of new skills and recalibration of motor commands when movement execution is consistently perturbed (adaptation). Growing evidence indicates that the cerebellum is also involved in cognition and mediates forms of cognitive learning. Therefore, the obvious question arises whether the cerebellum might play a similar role in learning and adaptation within the perceptual domain. We explored a possible deficit in visual perceptual learning (and adaptation) in patients with cerebellar damage using variants of a novel motion extrapolation, psychophysical paradigm. Compared to their age- and gender-matched controls, patients with focal damage to the posterior (but not the anterior) cerebellum showed strongly diminished learning, in terms of both rate and amount of improvement over time. Consistent with a double-dissociation pattern, patients with focal damage to the anterior cerebellum instead showed more severe clinical motor deficits, indicative of a distinct role of the anterior cerebellum in the motor domain. The collected evidence demonstrates that a pure form of slow-incremental visual perceptual learning is crucially dependent on the intact cerebellum, bearing the notion that the human cerebellum acts as a learning device for motor, cognitive and perceptual functions. We interpret the deficit in terms of an inability to fine-tune predictive models of the incoming flow of visual perceptual input over time. Moreover, our results suggest a strong dissociation between the role of different portions of the cerebellum in motor versus non-motor functions, with only the posterior lobe being responsible for learning in the perceptual domain.
authors: Department of Neurological and Movement Sciences, University of Verona, Verona, Italy.
authors: Cristina
authors: C
authors: Deluca
authors: Department of Neurological and Movement Sciences, University of Verona, Verona, Italy; Department of Physiology, McGill University, Montreal, Canada.
authors: Ashkan
authors: A
authors: Golzar
authors: Department of Neurological and Movement Sciences, University of Verona, Verona, Italy.
authors: Elisa
authors: E
authors: Santandrea
authors: Department of Neurological and Movement Sciences, University of Verona, Verona, Italy.
authors: Emanuele
authors: E
authors: Lo Gerfo
authors: Department of Neurological and Movement Sciences, University of Verona, Verona, Italy.
authors: Jana
authors: J
authors: Eštočinová
authors: Neurology Unit, Borgo Trento Hospital, Verona, Italy.
authors: Giuseppe
authors: G
authors: Moretto
authors: Department of Neurological and Movement Sciences, University of Verona, Verona, Italy; National Institute of Neuroscience, Verona, Italy.
authors: Antonio
authors: A
authors: Fiaschi
authors: Department of Genetics of Neurodegenerative and Metabolic Diseases, IRCCS Foundation Carlo Besta, Milan, Italy.
authors: Marta
authors: M
authors: Panzeri
authors: Department of Genetics of Neurodegenerative and Metabolic Diseases, IRCCS Foundation Carlo Besta, Milan, Italy.
authors: Caterina
authors: C
authors: Mariotti
authors: Department of Neurological and Movement Sciences, University of Verona, Verona, Italy; National Institute of Neuroscience, Verona, Italy.
authors: Michele
authors: M
authors: Tinazzi
authors: Department of Neurological and Movement Sciences, University of Verona, Verona, Italy; National Institute of Neuroscience, Verona, Italy. Electronic address: leonardo.chelazzi@univr.it.
authors: Leonardo
authors: L
authors: Chelazzi
mesh_terms: D000222:Adaptation, Physiological / Q000502:physiology*; D000328:Adult; D000368:Aged; D001931:Brain Mapping; D002531:Cerebellum / Q000502:physiology* / Q000503:physiopathology; D005260:Female; D006801:Humans; D007858:Learning / Q000502:physiology*; D008297:Male; D008875:Middle Aged; D009039:Motion Perception / Q000502:physiology*; D009483:Neuropsychological Tests; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult
keywords: Cerebellum; Motion extrapolation; Perceptual adaptation; Perceptual learning