Globus pallidus stimulation activates the cortical motor system during alleviation of parkinsonian symptoms.
Nat Med
; 3(6): 671-4, 1997 Jun.
Article
em En
| MEDLINE
| ID: mdl-9176495
ABSTRACT
Studies of 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP)-induced parkinsonism in monkeys suggest that excessive inhibitory outflow from the internal segment of the globus pallidus (GPi) suppresses the motor thalamus, which reduces activation of the cerebral cortex motor system, resulting in the slowness and poverty of movement of Parkinson's disease (PD). This hypothesis is supported by reports of high rates of spontaneous neuronal discharges and hypermetabolism in GPi (ref. 4-7) and impaired activation of the supplementary motor area (SMA) and dorsolateral prefrontal regions in PD patients. Furthermore, lesion or chronic high-frequency electrical (likely inactivating) stimulation of GPi (ref. 10-14) is associated with marked improvements in akinesia and rigidity, and the impaired activation of SMA is reversed when the akinesia is treated with dopamine agonists. To test whether improvement in motor function with pallidal surgery can be attributed to increased activity in premotor cortical regions, we assessed the changes in regional cerebral blood flow (rCBF) and parkinsonian symptoms during disruption of GPi activity with high-frequency stimulation delivered through implanted brain electrodes. Positron emission tomography (PET) revealed an increase in rCBF in ipsilateral premotor cortical areas during GPi stimulation, which improved rigidity and bradykinesia. These results suggest that disrupting the excessive inhibitory output of the basal ganglia reverses parkinsonism, via a thalamic relay, by activation of brain areas involved in the initiation of movement.
Buscar no Google
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Doença de Parkinson
/
Doença de Parkinson Secundária
/
Encéfalo
/
Terapia por Estimulação Elétrica
/
Globo Pálido
Tipo de estudo:
Diagnostic_studies
Limite:
Aged
/
Female
/
Humans
/
Male
/
Middle aged
Idioma:
En
Ano de publicação:
1997
Tipo de documento:
Article