title: Reactivity to visual signals and the cerebellar vermis: Evidence from a rare case with rhombencephalosynapsis.
abstract: The modulatory role of the cerebellum was investigated in a case with rhombencephalosynapsis (RS), a rare dysplasia characterized by the absence of the cerebellar vermis. The visual psychophysical task involved localizing a target and ignoring a distractor appearing either before, at the same time as, or after the target. It allowed us to assess reactivity to warning signals, distraction, and reactivity to signals appearing during attentive processing. Compared with a control sample, the patient exhibited greater reactivity to warning signals and difficulties interrupting attentive processing, whereas distraction was not increased. Complementary analyses showed that these deficits did not reflect just delayed development of attentional processes. These results suggest that the cerebellum modulates responsiveness and commands attentional/exploratory flexibility in response to sensory signals.
authors.affiliation: Université Lumière-Lyon 2, Laboratoire d'Etude des Mécanismes Cognitifs, Département de Psychologie Cognitive Expérimentale & Neuropsychologie, Bron Cedex, France. george.michael@univ-lyon2.fr
authors.forename: George A
authors.initials: GA
authors.lastname: Michael
authors.forename: Sophie
authors.initials: S
authors.lastname: Garcia
authors.forename: Gérald
authors.initials: G
authors.lastname: Bussy
authors.forename: Laurence
authors.initials: L
authors.lastname: Lion-François
authors.forename: Laurent
authors.initials: L
authors.lastname: Guibaud
mesh_terms: D000293:Adolescent; D000377:Agnosia; D001288:Attention / Q000502:physiology*; D001927:Brain Diseases / Q000473:pathology*; D002531:Cerebellum / Q000002:abnormalities* / Q000503:physiopathology; D002648:Child; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods; D008297:Male; D009483:Neuropsychological Tests; D011601:Psychophysics; D011930:Reaction Time / Q000502:physiology; D012249:Rhombencephalon / Q000002:abnormalities* / Q000503:physiopathology; D013997:Time Factors; D014796:Visual Perception / Q000502:physiology*