title: Changes of cortico-striatal effective connectivity during visuomotor learning.
abstract: It has been suggested that the cortico-striatal system might play a crucial role in learning behavioural plans of action. We have tested this hypothesis by studying the dynamics of functional coupling among the neural elements of cortico-striatal circuitry. Human cerebral activity was measured with functional magnetic resonance imaging (fMRI) during the learning of an associative visuomotor task. Structural equation modelling of regional fMRI time-series was used to characterize learning-related changes in effective connectivity. We report that learning to associate visual instructions with motor responses significantly altered cortico-striatal functional couplings. Specific learning-related increases of effective connectivity were found in temporo-striatal and fronto-striatal circuits. Connectivity among portions of the frontal cortex decreased as a function of learning. Temporo-frontal and parieto-frontal couplings were not altered during learning. We infer that novel visuomotor associations are established through the enhancement of specific cortico-striatal circuits, rather than through the alteration of direct temporo-frontal or parieto-frontal connectivity.
authors.affiliation: F.C. Donders Centre for Cognitive Neuroimaging, University of Nijmegen, NL-6500 HB Nijmegen, The Netherlands. ivan.toni@fcdonders.kun.nl
authors.forename: Ivan
authors.initials: I
authors.lastname: Toni
authors.forename: James
authors.initials: J
authors.lastname: Rowe
authors.forename: Klaas E
authors.initials: KE
authors.lastname: Stephan
authors.forename: Richard E
authors.initials: RE
authors.lastname: Passingham
mesh_terms: D002540:Cerebral Cortex / Q000502:physiology*; D003342:Corpus Striatum / Q000502:physiology*; D006801:Humans; D007858:Learning / Q000502:physiology*; D016014:Linear Models; D008279:Magnetic Resonance Imaging / Q000706:statistics & numerical data; D009434:Neural Pathways / Q000502:physiology; D010775:Photic Stimulation / Q000379:methods; D011597:Psychomotor Performance / Q000502:physiology*