Changes of Components of Topographic Event Related Potential P300 in Aging Process

Han, Sang Ick; Jeon, Yang Whan

Abstract

OBJECTS: This study was to examine the changes of components of topographic auditory event related potential P300 in normal aging process.
METHODS
The subjects were consisted of 85(range of age ; 18-68), who were right handed and had education level at least over 12 years. They had no history of medico-surgical and psychiatric illness which could cause brain dysfunction, and had not any physical and mental illness on examination. The topographic auditory event related P300 was recorded in oddball paradigm and the components of P300 including latency, amplitude, and location of maximum amplitude in X-Y cordinates were analized by computerized EP mapping system. The latency of P300 was determined by both Global Field Power Measurement and classic method.
RESULTS
In global field power measurement, the latency has been increased about by 1m sec per year(latency=299.9+1 X AGE). The location of maximum amplitude in X coordinate was moved by 0.018 per year toward left side(X=3.6-0.018 X AGE) and in Y coordinate by 0.017 toward frontal direction(Y=2.15+0.017 X AGE). In classic method the latency has been increased about by 0.82m sec per year(latency=304.76+0.82 X AGE). The location of maximum amplitude in X coordinate was moved by 0.011 per year toward left side(X=3.35-0.011 X AGE) and in Y coordinate by 0.025 toward frontal direction(Y=1.86+0.025 X AGE). The amplitudes were not changed in both methods.
CONCLUSION
The results showed strong positive correlation between latency of P300 and aging process, and slight left frontal displacement of the location of maximum amplitude. These finding implicate that psychophysiological function expressed by P300 was declined in aging process and database of formal controls should be necessary for both research and clinical application.