The power of suggestion: another examination of misattribution and insomnia.

This experiment was conducted in an attempt to replicate and delimit the reverse placebo effect found by Storms and Nisbett in insomniacs. It was predicted that the reverse placebo effect would obtain when the pills' effects were described as affecting arousal (as in Storms and Nisbett's study) but that a direct suggestion effect would result when the pills were described as directly affecting sleep onset latency. Results indicated that direct suggestion effects obtained regardless of the focus of the instructions. The present study together with the findings of Kellogg and Baron call into question the reliability and clinical significance of the reverse placebo effect in the treatment of insomnia.