Quantitative EEG Analysis of Executive Dysfunction in Parkinson Disease

Abstract

Quantitative EEG evaluation in Parkinson disease (PD) reveals diffuse slowing. This is the first quantitative EEG evaluation of the differences between PD with and without executive dysfunction (ExD). The subjects were 32 PD patients without remarkable dementia. The lack of ischemic lesions was confirmed by magnetic resonance imaging. ExD was defined as <70 points on the age-controlled standardized score of the Behavioral Assessment of the Dysexecutive Syndrome. Absolute power was measured for four frequency bands from delta to beta. Electrodes were placed at frontal pole, frontal, central, parietal, occipital, and temporal locations. Spectral ratio was calculated as the sum of power values for alpha and beta waves divided by the sum of values for the slow waves. In multiple logistic regression analysis of each electrode location, the dependent variable was ExD or not, and the independent variables were spectral ratio, age, and Unified Parkinson Disease Rating Scale. The only significant predictor of ExD was spectral ratio at the frontal pole (P = 0.031) and frontal (P = 0.048) locations. PD with ExD exhibited an increase in slow wave activity and a decrease in alpha and fast wave activities in these locations. These findings indicated that the ExD in PD was caused by frontal dysfunction.

Correlation of EEG Slowing with Cognitive Domains in Nondemented Patients with Parkinson's Disease

“…Taken together, our results are in line with other studies reporting EEG slowing as a surrogate marker for cognitive decline in patients with PD [6,7,8,9,10,11]. The lack of correlation between EEG power with working memory and visuospatial functions suggests that these domains are regulated at least in part by other mechanisms than are attention, episodic long-term memory, fluency, and executive functions.…”

“…Slowing of oscillatory brain activity (EEG and MEG) has been proposed as a surrogate marker of cognitive dysfunction [6,7,8,9,10,11], and has also been identified as a predictive marker of dementia in PD [12,13]. However, at present, it is not clear whether the EEG slowing in PD is a marker of overall cognition, or whether it is related to specific cognitive domains.…”

Abnormalities of Cortical Neural Synchronization Mechanisms in Subjects with Mild Cognitive Impairment due to Alzheimer’s and Parkinson’s Diseases: An EEG Study

“…The procedure is reported in the following. Firstly, we selected the standard fixed frequency bands in line with previous field studies of our research group [14,[32][33][34][35], namely delta (2-4 Hz), theta (4-8 Hz), alpha1 (8.5-10 Hz), alpha2 (10.5-13 Hz), beta1 (13.5-20 Hz), beta2 (20)(21)(22)(23)(24)(25)(26)(27)(28)(29)(30), and gamma (30-40 Hz). Secondly, eLORETA solutions using the following fixed frequency bands were computed.…”

“…Furthermore, the PDD groups exhibited a spatial widespread slowing of the rsEEG rhythms, as represented by high delta and theta power compared to the Nold groups [15][16][17][18][19][20][21][22][23][24]. Compared with a PD group (normal cognition), the PDMCI and PDD groups exhibited lower alpha peak frequency, higher global delta and theta, and lower alpha and beta power density as surrogate markers of the cognitive status [25].…”

Behavioural Assessment of the Dysexecutive Syndrome (BADS): Adaptação e Evidências de Validade

“…Por muitos anos, a DP foi descrita como sendo uma desordem basicamente motora, negligenciando-se as alterações cognitivas e mentais associadas à patologia (Kamei, Morita, Serizawa, Mizutani, & Hirayanagi, 2010). No entanto, alterações cognitivas são uma importante causa de incapacidade funcional nesses pacientes, com uma prevalência que pode chegar a 93%, podendo ser tão limitantes quanto os sinais motores (Sammer, Reuter, Hullmann, Kaps, & Vaitl, 2006;Campos-Sousa, Campos-Sousa, Ataíde Jr., Soares, & Almeida, 2010).…”