Interhemispheric asymmetries in the perception of unimanual and bimanual cutaneous stimuli
Autor: | Patrizio Pasqualetti, Paola Cicinelli, R. Traversa, Maria Giuseppina Palmieri, Carlo Caltagirone, P.M. Rossini, Massimiliano Oliveri, Francesco Tomaiuolo |
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Rok vydání: | 1999 |
Předmět: |
genetic structures
medicine.medical_treatment media_common.quotation_subject Parietal lobe Posterior parietal cortex Stimulation Sensory system Somatosensory system behavioral disciplines and activities Transcranial magnetic stimulation Perception Cerebral hemisphere medicine Neurology (clinical) Psychology Neuroscience psychological phenomena and processes media_common |
Zdroj: | Brain. 122:1721-1729 |
ISSN: | 1460-2156 0006-8950 |
DOI: | 10.1093/brain/122.9.1721 |
Popis: | Previous studies have shown that transcranial magnetic stimulation (TMS) of the sensorimotor cortex can induce a suppression of cutaneous perception from the fingers of the contralateral hand. In this work, 17 normal subjects were submitted to focal TMS of frontal and parietal scalp sites of each hemisphere. TMS was delivered at two interstimulus intervals (20 and 40 ms) following a cutaneous electrical stimulation of the first, third and fifth digits of either hand or both hands near the subjective threshold of perception. The aim of our study was to investigate whether TMS could detect an asymmetrical hemispheric specialization in the sensory perception of unimanual and bimanual, ipsilateral and contralateral sensory stimuli. At each interpulse interval, the right parietal cortex was significantly more sensitive to TMS interference with stimulus detection for both contralateral and ipsilateral stimuli compared with the left parietal cortex. These effects were mainly evident during bimanual discrimination tasks. Our results are indicative of an interhemispheric difference in the detection of cutaneous sensation, showing right hemispheric prevalence in the perception of contralateral as well as of ipsilateral stimuli. They provide neurophysiological support in normal humans to the clinical evidence which indicates that right hemisphere lesions can indeed produce deficits in the perception of ipsilateral sensory stimuli. |
Databáze: | OpenAIRE |
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