Perceptual Defense in the Choice Reaction Time

This paper is to show that the perceptual defense is involved in the choice reaction time (RT) task. For this pupose 12 naive introverted students selected from a 60 students class by the Murphy introvert-extravert Test served as Ss. After measuring the simple reaction time to a light stimulus, the Ss were trained under the choice reaction time task with two light stimuli, (other than/that used in the simple RT task) only one of which was followed by electric shock. Then they were tested for their reaction imes to the three light stimuli. By comparing the mean RT's to the stimulus followed by shock and to the other stimulus in the training and test sessions, one could not find the phenomenon of perceptual defence aquired through training. These results many be due to the Ss' failure to discriminate the light stimulus followed by shock from the other one not followed by shock.