Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0030567 (Parkinson's disease)
 63,064 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Auditory event-related potentials (ERP) elicited in a target detection stimulus paradigm and pattern-shift visual ERPs were studied in 20 male patients with idiopathic Parkinson disease (PD) and 20 age-matched normal controls. Patients showed significantly increased latencies for both the P200 and P300 components of the auditory ERP. Patients and controls showed no significant differences in latency of the visual ERP but patients showed significantly decreased amplitude. Only one of five neuropsychological measures, the Symbol Digit Modalities test (SDMT), showed a significant negative correlation with P300 latency. The significant association between the two measures that showed impairments in the PD patients (P300 latency and SDMT scores) suggested that these measures reflect a common, disrupted aspect of cognitive function in PD.
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PMID:Cognition in Parkinson disease: an event-related potential perspective. 711 9

The event-related potential (ERP), somatosensory evoked potential (SEP) and visual evoked potential (VEP) were studied in 15 patients with Alzheimer's disease (AD), 16 patients with Parkinson's disease with dementia (PD), 7 patients with Binswanger's disease (BD) and 15 normal controls. ERP was recorded during auditory discriminative tasks. SEP evoked by median nerve stimulation was recorded from the second cervical vertebra and contralateral primary somatosensory cortex with a midfrontal reference. VEP was recorded during pattern reversal stimulation. All three groups with dementia showed significant prolongation of the N200 and P300 latencies of ERP compared with the normal controls. In addition, patients with AD showed significant prolongation of the P200 latency. There was a significant correlation between the P300 latency of ERP and MMSE scores in AD patients. Patients with AD and PD showed significant prolongation of the interpeak latency between N13 and P40 (N13-P40) and N20-P40 of SEP compared with the normal controls. Patients with BD showed significant prolongation of the N13-N20, N13-N33, N13-P40 and N20-P40. These results suggest that there is impairment of the ascending somatosensory pathway in patients with dementia. Patients with PD showed significant prolongation of the P100 latency of VEP compared with normal controls. There was a significant correlation between the N200 latency of ERP and the P100 latency of VEP in PD patients. The VEP results suggest that dysfunction in the central visual system plays a role in abnormal pattern VEP in PD. In conclusion, the present results show that these three dementing diseases have different electrophysiological features, which may be related to the underlying pathogenic mechanisms. Additionally, the measurement of multimodal evoked potentials may be helpful in the differential diagnosis of patients with dementia.
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PMID:[Multimodal evoked potentials in patients with dementia]. 811 43

Somatosensory ERPs and short latency somatosensory evoked potentials (SSEPs) were studied in patients with dementia of the Alzheimer type (DAT), those with vascular dementia, demented and non-demented patients with Parkinson's disease, and healthy control subjects. In control subjects, latencies of N140, P200, N240 and P300 components increased with age at a rate of 0.2, 0.2, 0.6 and 1.5 msec/year, respectively. Patients with DAT and demented patients with Parkinson's disease had normal SSEPs as well as normal P100, and N140 latencies, but patients with vascular dementia showed prolonged N140 and P200 latencies in addition to a prolonged central conduction time (CCT). Analysis of N140 and P200 components of somatosensory ERPs may be important for evaluation of patients with vascular dementia. In patients with DAT, those with vascular dementia and demented patients with Parkinson's disease, the P300 latency was significantly prolonged compared with that in age-matched control subjects. However, the P300 latency did not show any significant differences among the groups of demented patients.
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PMID:Somatosensory event-related potentials (ERPs) in patients with different types of dementia. 815 5

Auditory and somatosensory ERPs were studied in patients with dementia of the Alzheimer type (DAT), those with vascular dementia and demented patients with idiopathic Parkinson disease. In both auditory and somatosensory modalities, the P3 latency in the demented patient group was significantly prolonged compared with the control data. However, comparisons of the P3 latency among the patients with DAT, vascular dementia and demented Parkinson did not reveal any significant differences. Patients with vascular dementia had significantly prolonged N140 and P200 latencies in somatosensory ERPs, whereas N1 and P2 latencies in auditory ERPs did not show any significant differences. Patients with acute onset hippocampal amnesia showed normal auditory P3 and somatosensory P3, whereas patients with diencephalic amnesia had prolonged auditory P3 and somatosensory P3 in addition to the abnormal short latency somatosensory evoked potentials. Analysis of passively evoked P3 component and comparison between target P3 and passively evoked P3 may be useful for evaluation of demented patients with a variety of etiologies. Single-trial analysis showed a greater variance of P3 latency in demented patients than in control subjects. A greater variance of P3 resulted in 'absent P3' in conventional averaging in some of the demented patients. As vigilance levels changed from trial to trial, evaluation of P3 latency variance has been proven to be useful.
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PMID:[Recent advances in clinical application of event-related potentials]. 828 96

The event-related potential (ERP) and visual evoked potential (VEP) were recorded in 28 patients with Parkinson's disease (PD) and 28 normal subjects. Nine of the PD patients had dementia and 19 did not. Dementia was evaluated according to the criteria for dementia assigned by the DSM III-R, and mental faculties were estimated using the Mini-Mental State Examination (MMSE). ERP was recorded during auditory discriminative tasks. The latencies of N100, P200, N200 and P300 from the Pz region were measured. VEP was recorded during pattern reversal stimulation. The latency of P100 was measured for each eye stimulated. PD patients with dementia showed significant prolongation of the N200 and P300 latencies of ERP and of the P100 latency of VEP compared with the values in normal subjects and in PD patients without dementia. There was a significant correlation between the N200 latency of ERP and the P100 latency of VEP in PD patients with dementia. The findings indicate that the N200 and P300 latencies of ERP are related to cognitive information processing and also suggest that dysfunction in the central visual system plays a role in abnormal pattern VEP in patients with dementia. Furthermore, the disturbance of early sensory processing in response to visual stimuli may roughly parallel the impairment of cognitive information processing in terms of ERP in PD patients with dementia.
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PMID:[Event-related potential and visual evoked potential in patients with Parkinson's disease]. 833 29

While it is known that both primary visual processes and visuocognitive responses are affected in Parkinson's Disease (PD), their relationship is not known. It is known that both of these measures can be affected by age per se. Our aims were to determine if in non-demented PD patients visual cognitive event-related potential (ERP) changes simply reflect abnormal primary visual processing and to determine the effects of age and disease on their relationship. In order to do so, we introduce a new normalizing procedure for visual ERPs. In addition to the latencies and amplitudes of P100, N140, P200, N200 and P300 components, the P300-P100 latency difference (termed "central processing time"-CPT) were measured. In order to avoid confounding factors of absolute amplitude differences due to say, generally low voltage recordings or poor primary visual responses, P300 responses normalized to P100 responses were also evaluated (P300/P100 amplitude ratio). Visual ERPs were obtained in an "oddball" paradigm in 20 nondemented patients with PD and 20 normal age-matched subjects. The stimuli were horizontal sinusoidal gratings differing only in spatial frequency (0.5 and 1 cycle/degree). While simple ERP latency criteria did not distinguish non-demented PD patients as a group from controls, when younger PD patients were compared to older PD patients and controls CPT acceleratedly increased in younger PD patients. The amplitudes of both N200 and P300 provided significant distinction between patient and control groups. The surprising result emerging from this study is that an individually normalized P300 amplitude provides significant distinction of younger PD patients from age matched normals.
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PMID:Simultaneously evoked primary and cognitive visual evoked potentials distinguish younger and older patients with Parkinson's disease. 901 93

Simultaneous measures of Event Related Potentials (ERP) and electrodermal activity (EDA) allow the delineation of ERPs that did, and did not, evoke an electrodermal 'Orienting Reflex' (OR). The OR is an automatic reflex invoked by novel or significant stimuli. Our group have developed a model to quantify electrodermal OR activity acquired in conventional late component ERP paradigms with short interstimulus intervals. Target late component (N100, P200, N200, P300) ERPs (acquired in an auditory oddball paradigm) and EDA was examined in 15 Parkinson's disease (PD) subjects and 50 normal controls. Single-trial target ERPs were averaged according to whether or not they elicited an electrodermal OR. Compared with controls, the PD group showed significantly decreased N100 and N200 amplitudes in the OR related ERPs ('Orienting ERPs'). These preliminary findings suggest that conventional late component ERPs can be delineated according to whether or not they evoked an OR. The 'orienting ERPs' in PD showed more significant disturbances compared with controls, than ERPs that did not evoke an OR.
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PMID:Automatic processing dysfunction in Parkinson's disease. 942 61

Late components of the event-related potential (ERP; N100, P200, N200, and P300) were elicited using an auditory oddball paradigm (with a button-press response to target stimuli) in 15 Parkinson's disease (PD) patients and 50 normal control subjects. Compared with control subjects, PD subjects showed a significant decrease in N200 amplitude. Between-group topographical differences in N200 amplitude were evident at central (C3, Cz, C4) and temporal (T5, T3, T4, T6) regions. The results may reflect a deficit in response selection in PD possibly resulting from a dysfunction associated with the abnormalities in the central and temporal regions found to have a decreased N200 amplitude compared with normal control subjects in this study.
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PMID:Late components of the event-related potentials and their topography in Parkinson's disease. 953 39

The analysis of long-latency event-related potentials (ERPs) is of importance in the evaluation of certain cognitive functions and in following their subsequent changes. The aim of the present study was to investigate whether deep brain stimulation (DBS) itself can cause changes in the configuration of the ERPs. Using a standard oddball auditory paradigm, we elicited auditory cognitive ERPs in 23 Parkinson's disease patients (in both DBS-ON and DBS-OFF conditions) and in 14 healthy controls. The P200 and P300 amplitudes and latencies, the motor reaction times and the accuracy of button pressing were compared between the DBS-ON and DBS-OFF states and subsequently correlated with the applied stimulation voltage and disease duration. Comparison of the DBS-ON and DBS-OFF conditions revealed that neither the amplitude nor the latency of the examined ERP components changed significantly. However, the behavioral and attentional aspects (e.g. the accuracy of the button pressing responses to the target signal) definitely improved after the DBS was turned on. Positive correlations were demonstrated between the P300 amplitudes over the central and frontal regions and the optimal stimulation voltage and between the disease duration and P300 latencies over the Cz and Fz sites. In conclusion, our data indicate that DBS may have different impacts on various electrophysiological parameters during the oddball paradigm.
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PMID:The impact of bilateral subthalamic deep brain stimulation on long-latency event-related potentials. 1831 71

Parkinson's disease (PD) has been related to impaired processing of emotional speech intonation (emotional prosody). One distinctive feature of idiopathic PD is motor symptom asymmetry, with striatal dysfunction being strongest in the hemisphere contralateral to the most affected body side. It is still unclear whether this asymmetry may affect vocal emotion perception. Here, we tested 22 PD patients (10 with predominantly left-sided [LPD] and 12 with predominantly right-sided motor symptoms) and 22 healthy controls in an event-related potential study. Sentences conveying different emotional intonations were presented in lexical and pseudo-speech versions. Task varied between an explicit and an implicit instruction. Of specific interest was emotional salience detection from prosody, reflected in the P200 component. We predicted that patients with predominantly right-striatal dysfunction (LPD) would exhibit P200 alterations. Our results support this assumption. LPD patients showed enhanced P200 amplitudes, and specific deficits were observed for disgust prosody, explicit anger processing and implicit processing of happy prosody. Lexical speech was predominantly affected while the processing of pseudo-speech was largely intact. P200 amplitude in patients correlated significantly with left motor scores and asymmetry indices. The data suggest that emotional salience detection from prosody is affected by asymmetric neuronal degeneration in PD.
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PMID:An ERP study of vocal emotion processing in asymmetric Parkinson's disease. 2295 65


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