Injection of an animal with amphetamine leads to heart rate acceleration. With repeated injections, however, the injection procedure alone (i.e., when an inert substance is injected) can elicit heart rate acceleration. In this situation, which of the following is true?
A) The injection procedure is the CS.
B) Heart rate acceleration is both the UR and the CR.
C) Amphetamine is the US.
D) All of the above answers are correct.

Question

Quizplus · Accepted Answer

The injection procedure becomes the conditioned stimulus (CS) because it is a neutral stimulus that, through association with the unconditioned stimulus (amphetamine), now elicits a response. Heart rate acceleration is both the unconditioned response (UR) to the amphetamine and the conditioned response (CR) to the injection procedure. Amphetamine is the unconditioned stimulus (US) because it naturally elicits the response of heart rate acceleration without prior conditioning.

Injection of an Animal with Amphetamine Leads to Heart Rate