EEG-Derived Functional Connectivity Patterns Associated with Mild Cognitive Impairment in Parkinson's Disease.

OBJECTIVE: To evaluate EEG-derived functional connectivity (FC) patterns associated with mild cognitive impairment (MCI) in Parkinson's disease (PD). METHODS: A sample of 15 patients without cognitive impairment (PD-WCI), 15 with MCI (PD-MCI), and 26 healthy subjects were studied. The EEG was performed in the waking functional state with eyes closed, for the functional analysis it was used the synchronization likelihood (SL) and graph theory (GT). RESULTS: PD-MCI patients showed decreased FC in frequencies alpha, in posterior regions, and delta with a generalized distribution. Patients, compared to the healthy people, presented a decrease in segregation (lower clustering coefficient in alpha p = 0.003 in PD-MCI patients) and increased integration (shorter mean path length in delta (p = 0.004) and theta (p = 0.002) in PD-MCI patients). There were no significant differences in the network topology between the parkinsonian groups. In PD-MCI patients, executive dysfunction correlated positively with global connectivity in beta (r = 0.47) and negatively with the mean path length at beta (r = -0.45); alterations in working memory were negatively correlated with the mean path length at beta r = -0.45. CONCLUSIONS: PD patients present alterations in the FC in all frequencies, those with MCI show less connectivity in the alpha and delta frequencies. The neural networks of the patients show a random topology, with a similar organization between patients with and without MCI. In PD-MCI patients, alterations in executive function and working memory are related to beta integration.

Potencial P300 durante una tarea de atención sostenida en pacientes conenfermedad de Parkinson / P300 event-related potential during sustained attention in Parkinson's disease patients

Objetivo: Evaluar la relación entre el potencial relacionado a eventos P300 con significado atencional visual y los resultados de la evaluación neuropsicológica en pacientes conenfermedad de Parkinson en estadios II y III de Hoehn y Yahr.Métodos: Se realizó un estudio analítico transversal donde se evaluaron 57 pacientes con enfermedad de Parkinson idiopática, atendidos entre diciembre de 2017 y abril de 2018, en el Centro Internacional de Restauración Neurológica, de La Habana. Se realizó el registro de P300, durante la ejecución de una tarea de atención sostenida visual. Se midió latencia y amplitud de la P300, lo que se correlacionó (test de correlaciones de Spearman, p< 0,01)con las variables demográficas, variables de eficiencia en la tarea de atención sostenida y variables neuropsicológicas. Se compararon los resultados de los grupos II y III de Hoehn y Yahr con respecto a todas las variables estudiadas (test de la U de Mann Whitney, p< 0,05).Resultados: Se constató una significativa diferencia de latencia entre grupos del componente P300 en el electrodo Pz. Fue más prolongado en el grupo III de Hoehn y Yahr.Se evidenciaron en el grupo II correlaciones negativas entre la latencia de P300 y el test de batería de evaluación frontal, y positivas entre la latencia de P300 y la prueba de Stroop.Las correlaciones entre el test de ba(AU)

Objective: To evaluate the relationship between the P300 event-related potential with visual attention significance and the results of neuropsychological evaluation in patientswith Parkinson's disease in Hoehn and Yahr stages II and III.Methods: A cross-sectional analytical study was carried out evaluating 57 patients with idiopathic Parkinson's disease, who were treated from December 2017 to April 2018 at theInternational Center for Neurological Restoration, in Havana. P300 was recorded during the execution of a visual sustained attention task. The latency and amplitude of P300 weremeasured, which was correlated (Spearman's correlation test, p <0.01) with demographic variables, efficiency variables in the sustained attention task and neuropsychological variables. The results of Hoehn and Yahr groups II and III were compared with respect to all the variables studied (Mann Whitney U test, p <0.05).Results: Significant latency difference was found between groups of P300 component in Pz electrode. It was more prolonged in Hoehn and Yahr group III. Negative correlations were found in group II between P300 latency and the frontal evaluation battery test, andpositive correlations between P300 latency and Stroop test. The correlations between the frontal evaluation battery test and P300 amplitude were positive, and between Stroop test and P300 amplitude were negative. Similar results were evident in group III regarding P300 amplitude, which corresponded to worse performance in the neuropsychological evaluation.Conclusions: A close relationship between P300 event-related potential with visual attention significance and the results of the neuropsychological evaluation in Parkinson's disease patients, in Hoehn and Yahr stages II and III, was verified. P300 potential was an objective examination that reinforced the validity of the neuropsychological evaluationresults(AU)

Influencia de la función ejecutiva: compensación de la disfunción motora en pacientes con enfermedad de Parkinson / Influence of the executive function: compensation of the motor disfunction in patients with Parkinson's disease

El sistema motor posee.

The motor system.