다음 빈칸에 들어갈 말로 가장 적절한 것을 고르시오. [3점]
In a classic experiment from 1972, participants were divided into two groups. The members of the first group were told that they would receive a small electric shock. In the second group, subjects were told that the risk of this happening was only 50 percent. The researchers measured physical anxiety (heart rate, nervousness, sweating, etc.) shortly before starting. The result was, well, shocking: There was absolutely no difference. Participants in both groups were equally stressed. Next, the researchers announced a series of reductions in the probability of a shock for the second group: from 50 percent to 20 percent, then 10 percent, then 5 percent. The result: still no difference! However, when they declared they would increase the strength of the expected current, both groups’ anxiety levels rose—again, by the same degree. This illustrates that we respond to the expected magnitude of an event, but not to its ______________.