Abstract
Although the ECS is known to impair the earned response, its effect upon the inhibition of the response is not evident. The only available data are those on the effect upon the extinction of avoidance response. The extinction of avoidance, however, is different from the other type of extinction, since the former is an extinction of motive rather than that of response. In the present experiment, the effect of ECS upon the experimental extinction of response was studied.
Method. Thirty albino rats were condiioned to respond in the Skinner-Box for 5 days with 20 reinforcements per day. Then the response was extinguished for 3 days with the period of non-reinforcement of 30 minutes per day, which was followed further by another term of extinction of 3 days with the daily criterion of 5-minutes'-non-response. Then the rats were divided into experimental and control groups. The experimental group was led to the electric shock convulsion for the next 5 days, 2 times a day by the current of 30mA with 1500V through the ear lobes. During this period, the control group was given a rest. The test was extinction trials with the criterion of 5-minutes'-non-response each day for 3 days.
Results. The mean number of responses was shown in Fig. 1 for every 5 minutes and in Fig. 2 and 4 for every day. The number of responses during the test period was greater in the experimental group than in the control group, in which a large individual difference was observed in the experimental group (Fig. 3). The time to attain the criterion was greater in experimental group than in the other (Fig. 5). There was no significant difference in the latency time between the two groups (Fig. 6).
The ECS was found to interfere the extinction and permit the response to recover rapidly. This effect of ECS varied from individual to individual possibly in accordance with the inborn nature of the individual.
