Spontaneous skepticism: the interplay of motivation and expectation in responses to favorable and unfavorable medical diagnoses.

The quantity of processing view of motivated reasoning predicts that individuals are more likely to spontaneously question the validity of unfavorable than favorable feedback even when the objective likelihood of the feedback is equivalent. Participants were videotaped self-administering a bogus medical test revealing either a favorable or an unfavorable result. In Studies 1 and 2, unfavorable result participants required more time to accept the validity of the test result and were more likely to spontaneously recheck its validity than were favorable result participants. However, unfavorable results also were perceived as less expected than were favorable results, even though the information supplied about their objective likelihood was identical. Study 3 showed that participants evaluating another student's results perceived favorable and unfavorable outcomes as equally likely, suggesting that the subjective likelihood of positive and negative feedback is also subject to motivational influence.