In the middle of a study concerning pain reduction, you give a participant a pill and tell him it is a painkiller. It is actually a sugar pill. The person feels a reduction of pain. The ______ effect helps to explain how this can happen.
A. sample
B. replication
C. manipulation
D. placebo
Answer:D
In the middle of a study concerning pain reduction, you give a participant a pill and tell him it is a painkiller. It is actually a sugar pill. The person feels a reduction of pain. The ______ effect helps to explain how this can happen.
A. sample B. replication C. manipulation D. placebo