Event-Related Potentials in Senile Dementia of Alzheimer's Type, Multiinfarct Dementia and Parkinson's Disease

Abstract: We investigated event-related potentials (P300) in three types of demented patients. Fourteen patients with senile dementia of Alzheimer's type (SDAT), 15 with multiinfarct dementia (MID), 8 with Parkinson's disease with dementia and 29 normal controls participated in this study. We measured the latencies of N100 and P300 at Pz after odd-ball paradigm stimulation. N100 peaks were within the normal range in all patients. However, P300 peaks were significantly delayed in all demented patients. There were no statistical differences in the mean latencies of P300 in each demented group. P300 latencies were found to be negatively correlated with Hasegawa's dementia scale. These results suggest that regardless of its cause dementia has similar influences on the P300 latency and P300 may be a useful means to assess the degree of dementia.