Insufficient processing resources in Parkinson's disease: evaluation using multimodal event-related potentials paradigm.
The purpose of our study was to demonstrate impaired allocation of processing resources in non-demented patients with early-stage mild Parkinson's disease (PD) using a multimodal event-related potential (ERP) paradigm. The multimodal ERP paradigm was performed in 18 non-demented medicated patients with early-stage PD (Mini-Mental State Examination Score >26) and 16 matched normal controls, the Global Field Power (GFP) was employed for ERP components analysis, and the new modified Wisconsin Card Sorting Test (WCST) was used to evaluate frontal lobe function. Patients with PD did not exhibit novelty P3s, and P3 latency to non-target novel stimuli in visual and auditory modalities was significantly longer in PD patients than in controls. P3 amplitude for the target stimuli (P3b) was higher in PD in both auditory and visual modalities; however, P3b latency was not different between the two groups. Patients with PD showed a significantly lower score of achieved categories and made more perseverative errors in WCST as compared to controls. Our results showed that there were no natural novelty P3s in patients with PD; this finding suggests that non-demented patients with mild PD do not have sufficient mental resources to allocate to the central executive, due to dysfunction of the frontal lobe.
Department of Neurology, Dokkyo University School of Medicine, Mibu, Tochigi, Japan.
Xiao-Hui
XH
Zeng
Koichi
K
Hirata
Hideaki
H
Tanaka
Akinori
A
Hozumi
Kaoru
K
Yamazaki
D000161:Acoustic Stimulation; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000704:Analysis of Variance; D001288:Attention / Q000502:physiology; D005071:Evoked Potentials / Q000502:physiology*; D005260:Female; D005625:Frontal Lobe / Q000503:physiopathology; D006801:Humans; D008297:Male; D008875:Middle Aged; D009483:Neuropsychological Tests; D010300:Parkinson Disease / Q000503:physiopathology* / Q000523:psychology; D010775:Photic Stimulation; D011569:Psychiatric Status Rating Scales; D011597:Psychomotor Performance / Q000502:physiology; D011930:Reaction Time