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: 3.22). 03/2008; 106(3):177-83. DOI: 10.1016/j.bandl.2008.01.007
Source: PubMed


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.

Download full-text


Available from: Luca F. Ticini, FRSA, Oct 04, 2015
24 Reads
  • [Show abstract] [Hide abstract]
    ABSTRACT: The Norwegian system operator plans to change from (N-1) to a more flexible cost-based security criterion. The approach is illustrated using a simple example and then compared with alternative decision paradigms. The comparison shows how different paradigms may change ranking of operating alternatives and that the new cost-based criterion still tends to favor alternatives close to (N-1), provided application of a penalty factor giving additional and significant weight on interruption costs. Copyright (c) 2007 John Wiley & Sons, Ltd.
    Probabilistic Methods Applied to Power Systems, 2004 International Conference on; 07/2007
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: A child's brain shows a remarkable ability to recover from adverse events such as stroke. Language functions recover particularly well, while visuo-spatial skills are more affected by brain damage, regardless of its localization. This study investigated the lateralization of language and visual search after childhood stroke. Ten patients with unilateral stroke (aged 10-19 years, five left-, five right-sided lesion) and 20 healthy controls (aged 8-20 years) completed a neuropsychological test battery and functional magnetic resonance imaging (fMRI) intended to activate predominantly right (visual search) and left-sided functional networks (language). After stroke, patients demonstrated atypical lateralization of visual search functions (8/10 patients, left lateralization) more often than that of language (4/10 patients, right lateralization). There was a dissociation between the lateralization of productive and semantic language (4/10 patients, 1/20 controls) and between the lateralization of simple and complex visual search (3/10 patients, 3/20 controls). In patients, atypical contralateral activations occurred in the same areas that showed decreasing activation during development in healthy participants. The lateralization of functions depends upon the cognitive function measured. Dissociation between the lateralization of different language or visual search tasks can occur.
    Brain Injury 04/2010; 24(6):859-70. DOI:10.3109/02699051003724978 · 1.81 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The developing human brain can compensate for pre- and perinatally acquired focal lesions more effectively than the adult brain. The mechanisms by which this effective reorganization is achieved vary considerably between different functional systems, reflecting differences in the normal maturation of these systems. In the motor system, descending cortico-spinal motor projections have already reached their spinal target zones at the beginning of the third trimester of pregnancy, with initially bilateral projections from each hemisphere. During normal development, the ipsilateral projections are gradually withdrawn, whereas the contralateral projections persist. When, during this period, a unilateral brain lesion disrupts the cortico-spinal projections of one hemisphere, the ipsilateral projections from the contralesional hemisphere will persist. This allows the contralesional hemisphere to take over motor control over the paretic extremities. Although this mechanism of reorganization is available throughout the pre- and perinatal period, the efficacy of this ipsilateral takeover of motor functions decreases with increasing age at the time of the insult. In the somatosensory system, ascending thalamo-cortical somatosensory projections have not yet reached their cortical target zones at the beginning of the third trimester of pregnancy. Therefore, these projections can still 'react' to brain lesions acquired during this period, and can form 'axonal bypasses' around periventricular white matter lesions to reach their original cortical target areas in the postcentral gyrus. Thus, somatosensory functions can be well preserved even in cases of large periventricular lesions. In contrast, when the postcentral gyrus itself is affected, no signs for reorganization have been observed. Accordingly, somatosensory functions are often poor in these patients. Language functions can be normal even in patients with extensive early left-hemispheric brain lesions. This is achieved by language organization in the right hemisphere, which takes place in brain regions homotopic to the classical left-hemispheric language areas in normal subjects. In patients with periventricular lesions, the degree of right-hemispheric takeover of language functions correlates with the severity of structural damage to facial (and, thus, articulatory) motor projections.
    Journal of Anatomy 10/2010; 217(4):469-74. DOI:10.1111/j.1469-7580.2010.01262.x · 2.10 Impact Factor
Show more