Cortical control of voluntary saccades in Parkinson's disease and pre-emptive perception.
Parkinsonism Relat Disord
; 18 Suppl 1: S100-3, 2012 Jan.
Article
em En
| MEDLINE
| ID: mdl-22166401
ABSTRACT
Gamma range EEG has been associated with cognition. Bodis-Wollner et al. [Ann NY Acad Sci 2002;956464-7] and Forgacs et al. [Perception 2008;37419-32] described posterior perisaccadic gamma (35-45 Hz) modulation associated with voluntary saccades. Voluntary impairment is a hallmark of Parkinson's disease (PD). We have done correlational analysis of frontally and posteriorly (posterior-parietal) recorded intrasaccadic gamma (ISG) powers, to understand cortical control of voluntary saccades in PD and healthy controls. Fifteen PD patients (55-71 years, 4 females) and 17 healthy controls (54-72 years, 9 females) participated in the study. The EEG was recorded over frontal and posterior-parietal scalp sites. Saccades were recorded with electro-oculogram and infra-red ISCAN camera. Subjects executed horizontal voluntary saccades to a mark; 15 degree distance rightwards or leftwards (centrifugal CF) from the central fixation, then back to the center (centripetal CP) and so on, for 2 minutes. Perisaccadic EEG segments were wavelet transformed followed by Hilbert transform to obtain ISG (35-45 Hz) powers. ISG power was trial-averaged, separately for the 4 possible saccade types; CP and CF, rightwards and leftwards. The perisaccadic EEG revealed disorganization in the intrasaccadic period. The correlations between frontal and posterior ISG power are high in PD (correlation coefficient >0.6) while low in controls (correlation coefficient <0.02). We interpret these results as lack of modulatory coupling between frontal and posterior intrasaccadic mechanisms in PD. Impaired volition in PD may be due to impaired circuitry of preemptive perception (PEP). Interareal phase coupling analysis will help in investigating the cortical voluntary saccade control with greater temporal precision.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Contexto em Saúde:
1_ASSA2030
Problema de saúde:
1_doencas_nao_transmissiveis
Assunto principal:
Doença de Parkinson
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Percepção
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Movimentos Sacádicos
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Volição
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Córtex Cerebral
Limite:
Aged
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Female
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Humans
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Male
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Middle aged
Idioma:
En
Revista:
Parkinsonism Relat Disord
Assunto da revista:
NEUROLOGIA
Ano de publicação:
2012
Tipo de documento:
Article
País de afiliação:
Estados Unidos