Article

Functional topography of early periventricular brain lesions in relation to cytoarchitectonic probabilistic maps.

Department of Pediatric Neurology and Developmental Medicine, University Children's Hospital, Hoppe-Seyler-Str. 1, D-72076 Tübingen, Germany.
Brain and Language (Impact Factor: 3.31). 03/2008; 106(3):177-83. DOI: 10.1016/j.bandl.2008.01.007
Source: PubMed

ABSTRACT Early periventricular brain lesions can not only cause cerebral palsy, but can also induce a reorganization of language. Here, we asked whether these different functional consequences can be attributed to topographically distinct portions of the periventricular white matter damage. Eight patients with pre- and perinatally acquired left-sided periventricular brain lesions underwent focal transcranial magnetic stimulation to assess the integrity of cortico-spinal hand motor projections, and functional MRI to determine the hemispheric organization of language production. MRI lesion-symptom mapping revealed that two distinct portions of the periventricular lesions were critically involved in the disruption of cortico-spinal hand motor projections on the one hand and in the induction of language reorganization into the contra-lesional right hemisphere on the other hand. Both regions are located in a position compatible with the course of cortico-spinal/cortico-nuclear projections of the primary motor cortex in the periventricular white matter, as determined by the stereotaxic probabilistic cytoarchitectonic atlas developed by the Jülich group.

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