ABSTRACT
The placebo effect is a psychobiological phenomenon whereby treatment cues trigger improvement. This chapter outlines what is known about the neurobiology of placebo effects, with particular emphasis on reward mechanisms and motivated behaviours. It focuses on some of the most significant studies that uncovered both psychological and biological mechanisms underlying placebo and placebo-like effects in addiction. Dopamine has also been found to be involved in placebo responses in both pain and Parkinson’s disease. Sensory cues including the sight and smell of smoke and handling of a cigarette have also been found to relate to placebo and placebo-like effects. Contrary to what should be expected, there is no clear-cut evidence of placebo and placebo-related effects in alcohol abuse. Placebo effects are most consistently found in studies on alcohol-induced sexual arousal, but there is only modest evidence to support powerful placebo effects across different domains of social behavior.
