The effects of feedback in psychophysical tasks

Previous results of the reinforcement effects of feedback in psychophysical tasks have been interpreted as changes in the S’s response bias in the uncertain sensory state. The present study varied the percentage of feedback in a two-altemative loud-soft recognition task. The values of the probability of correct feedback were 1, .8, .6, .4, .2, and 0. The results indicated that Ss learned to respond to agree with the experimental feedback rather than with the actual cue presented on a trial. The probability of a response on Trial n +1 was highly dependent upon the response and feedback of Trial n only when the two trials were the same. It was concluded that feedback must influence the response probability vector associated with a given detection state.