In psychologist Robert Rescorla's classical conditioning experiment, one group of rats experienced a tone just before each of 20 shocks. A second group of rats experienced the same number of tone-shock pairings, plus an additional 20 shocks with no tone. Rescorla found that the rats in the first group showed a much stronger conditioned fear response than the rats in the second group. How did Rescorla explain this finding?
A) It was an example of the partial reinforcement effect.
B) The second group of rats experienced spontaneous recovery.
C) The tone was a more reliable predictor of the shock for the first group of rats.
D) The interval between the tone and the shock was too great for the second group of rats to acquire a strong conditioned response (CR).

Question

Quizplus · Accepted Answer

Rescorla's findings suggest that the strength of a conditioned response depends on the reliability or predictiveness of the conditioned stimulus (CS). In the first group of rats, the tone was a reliable predictor of the shock, as it always occurred just before the shock. In contrast, the second group of rats experienced shocks with no preceding tone, reducing the reliability of the tone as a predictor of shock. Therefore, the rats in the first group developed a stronger conditioned fear response to the tone-CS than did the rats in the second group.

In Psychologist Robert Rescorla's Classical Conditioning Experiment, One Group of Rats