Yamashita K, Kobayashi S, Koide H, Yamaguchi S
Third Division of Internal Medicine, Shimane Medical University, Izumo, Japan.
No To Shinkei. 1991 Oct;43(10):945-50.
The P300 component of the event-related brain potential (ERP) is generated when subjects discriminate stimulus events which differ from one another. There are many reports about the effect of age on P300 in clinically normal subjects. However, these subjects may include individuals with silent cerebral infarctions or abnormal periventricular hyperintensity (PVH) on MRI. In this study, we completely excluded such subjects using MRI and examined the effect of aging on P300. One hundred four neurologically normal subjects (mean age 58.6 years, 55 men, 49 women) who had no lesions or severe PVH on MRI were selected. An oddball stimulus paradigm was employed and ERPs were elicited by presenting a series of binaural 1000 (82%) and 2000Hz (18%) tones through headphones. Prolongation of P300 latency was significantly correlated with advancing age (p less than 0.001): P300 latency increased by approximately 1.7 msec per year of age, with a prominent increase after age 60. But there was no significant difference between males and females in P300 latency. The significant correlation between age and P300 amplitude was observed only at Pz (p less than 0.05). These results indicate that there is a gradual mental decline with aging in normal subjects without silent cerebral infarctions or PVH.
当受试者辨别彼此不同的刺激事件时，会产生事件相关脑电位（ERP）的P300成分。关于年龄对临床正常受试者P300的影响，有许多报道。然而，这些受试者可能包括MRI显示有静息性脑梗死或脑室周围异常高信号（PVH）的个体。在本研究中，我们使用MRI完全排除了这类受试者，并研究了衰老对P300的影响。选择了104名神经功能正常的受试者（平均年龄58.6岁，男性55名，女性49名），他们的MRI检查没有病变或严重的PVH。采用了奇偶数刺激范式，通过耳机呈现一系列双耳1000Hz（82%）和2000Hz（18%）音调来诱发ERP。P300潜伏期的延长与年龄增长显著相关（p小于0.001）：P300潜伏期每年增加约1.7毫秒，60岁以后有显著增加。但P300潜伏期在男性和女性之间没有显著差异。仅在Pz处观察到年龄与P300波幅之间存在显著相关性（p小于0.05）。这些结果表明，在没有静息性脑梗死或PVH的正常受试者中，随着年龄增长存在逐渐的智力衰退。
