This study is aimed at quantifying the habituation of sympathetic skin response (SSR) with repeated stimuli. The electrical stimulations were applied with various intervals to 55 normal subjects.

The major results are as follows;

1) When six stimulations of the median nerve were given, separated in sequence by 10 sec, 5 sec, 15 sec, 2 min and 5 min, the habituation was significant at the 3rd, 5th and 6th response (p<0.001, p<0.01, p<0.001). The same stimulation of the tibial nerve did not show any significant habituation at all.

2) When six stimulations of the median nerve were given, separated by 20 sec, 15 sec, 25 sec, 2 min and 5 min, in sequence, the habituation was significant at the 6th response only (p<0.01). The same stimulation of the tibial nerve showed no significant habituation at all.

3) When ten stimulations of the median nerve were each separated equally by 10 sec, the habituation was significant from the 7th response (p<0.01). Stimulation of the tibial nerve showed significant habituation from the 3rd response (p<0.05).

4) When ten stimulations of the median nerve were each separated by 5 sec, the habituation was significant from the 2nd response (p<0.001). The same stimulation of the tibial nerve also showed significant habituation form the 2nd response (p<0.05).

It was concluded that significant habituation could be avoided up to the 6th response if stimuli are given with longer than a 10 second interval between stimuli.