The brain basis of positive and negative affect: evidence from a meta-analysis of the human neuroimaging literature

†K.A.L. and A.B.S. contributed equally to this work. The ability to experience pleasant or unpleasant feelings or to represent objects as “positive ” or “negative ” is known as representing hedonic “valence. ” Although scientists overwhelmingly agree that valence is a basic psychological phenomenon, debate continues about how to best conceptualize it scientifically. We used a meta-analysis of 397 functional magnetic resonance imaging (fMRI) and positron emission tomography studies (containing 914 experimental contrasts and 6827 participants) to test 3 competing hypotheses about the brain basis of valence: the bipolarity hypothesis that positive and negative affect are supported bya brain system thatmonotonically increases and/or decreases along the valencedimension, the bivalent hypothesis that positive and negative affect are supported by independent brain systems, and the affectiveworkspace hypothesis that positive and negative affect are supported by a flexible set of valence-general regions. We found little evidence for the bipolar or bivalent hypotheses. Findings instead supported the hypothesis that, at the level of brain activitymeasurable by fMRI, valence is flexibly implemented across instances by a set of valence-general limbic and paralimbic brain regions