Amplitude-time characteristics of the long-latency components (N1, N2, and P300) of acoustic evoked potential in healthy subjects

Abstract

The aim of the study was to trace the cumulative changes in the amplitude-time parameters of the AEP (acoustic evoked potential) components N1, N2, and P300 in the experimental situations of different complexities (counting and listening to sounds) and to compare the differences between young and mature subjects. The AEP was recorded in 12 healthy subjects aged 18 to 22 years and in 12 subjects aged 32 to 59 years. It was revealed that the components N1, N2, and P300 recorded in the situation of listening without any preliminary instruction did not differ in young and mature individuals. In the younger subjects, a higher N1 amplitude was revealed when they counted sounds, compared to listening, whereas the latency values of this component did not differ, irrespective of the complexity of the task. The component N2 was shown to demonstrate latency stability in relation to the age and the experimental situation. The N2 amplitude was higher in the situation of counting sounds in both age groups. The amplitude-time parameters of P300 did not differ in subjects of different ages in the listening task. The features of the components N1, N2, and P300 revealed in young and mature subjects in the experimental situations differing in complexity lead us to suggest that, with age, humans develop adaptive mechanisms contributing to successful task performance.