Abstract

The present experiment examined whether the amount of conditioned fear acquired in active avoidance learning varies with the degree of avoidance training. Fear-potentiated startle paradigm was used to measure the amount of conditioned fear. Rats were given 30 active avoidance training trials per day for 1, 2, 4, or 8 days using a light CS arid footshock US. After the training, fear-potentiated startle test was conducted for 3 days. The animals learned active avoidance rapidly, reaching an asymptote by the second day of training. In the Hist potentiated startle test, the conditioned fear to the CS was significant for all the training groups except for the 1-day training group. The conditioned fear extinguished gradually across the three tests. In each test, the amount of conditioned fear was not uniform, but gradually increased (test 1) or decreased (test 2) as the test proceeded. The main purpose of this study was to examine if overtraining of an active avoidance response eliminates or reduces conditioned fear to the CS used in the training, but the results indicated that there was no difference among the 2, 4, and 8-day training groups.