RESUMO
The use of event-related fMRI makes it possible to investigate spatio-temporal dynamics of cortical and subcortical human brain structures activity during voluntary movement performance in response to presentation of relevant verbal stimuli. The results of the study showed that voluntary movement was associated with higher contralateral brain activation in a number of areas: primary motor and somatosensory cortex, premotor cortex, supplementary motor area and insula with adjacent regions. Ipsilateral activation of the cerebellum also was observed. It should be emphasized that contralateral strio-pallidal complex and ventral thalamus showed significant response to motor tasks. Similarly, the dynamics of cortex and deep brain structures activation involving in the phasic and tonic components of voluntary movement was uncovered. We showed, in particular, the noticeable difference in brain activation between the right and left hand movement performance. The obtained results enable to enhance understanding of the role of deep brain structures in voluntary movement organization in human and motor control system as a whole.
Assuntos
Cerebelo/fisiologia , Córtex Cerebral/fisiologia , Fenômenos Fisiológicos do Sistema Nervoso , Córtex Somatossensorial/fisiologia , Adulto , Cerebelo/diagnóstico por imagem , Córtex Cerebral/diagnóstico por imagem , Feminino , Mãos , Humanos , Imageamento por Ressonância Magnética , Masculino , Córtex Motor/diagnóstico por imagem , Córtex Motor/fisiologia , Movimento/fisiologia , Radiografia , Córtex Somatossensorial/diagnóstico por imagemRESUMO
OBJECTIVE: Functional and structural brain abnormalities in people at high risk for psychosis is a subject of intensive studies in biological psychiatry over the last decades. We studied correlations between neurophysiological and neuroimaging parameters in ultra-high risk patients. MATERIAL AND METHODS: Fifty-six patients, aged 17-25 years, with nonpsychotic mental disorders were examined. The control group included 30 age- and sex-matched healthy people. Neurophysiological study measured sensory gating. Proton MR-spectroscopy was used to study metabolic processes in the brain (index for glutamate/glutamine, N-acetylaspartate and choline containing compounds in the dorsolateral prefrontal cortex and thalamus of both hemispheres as well as in the genu and splenium of the corpus callosum). RESULTS AND CONCLUSION: We found the abnormality of sensory gating in patients at ultra-high risk for endogenous psychosis that was not correlated with the metabolic parameters. The latter were normal or were normalized during treatment.
