One of the most fundamental constructs in the study of motivation is motivational direction, or the urge to approach versus avoid. Motivational direction may be mediated in part by neural activity in the frontal cortex. Specifically, individual differences in resting frontal asymmetry in the electroencephalogram (EEG) have been conceptualized as a trait-like disposition that reflects basic motivational and affective tendencies. Greater relative left frontal activity has been associated with

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... t approach motivation and positive affect, whereas greater relative right frontal activity has been associated with trait avoidance motivation and negative affect. The current meta-analysis estimated the relationships between resting frontal EEG asymmetry and traits related to approach and avoidance. We also tested between two prominent models of frontal asymmetry, namely the affective valence model and the motivational direction model. Across 112 studies (N = 7,473) we found significant relationships consistent with predictions: Trait approach motivation and positive affect related to relatively greater left frontal asymmetry at rest (r = 0.076), whereas trait avoidance motivation and negative affect related to relatively greater right frontal asymmetry at rest (r = -0.066). Findings regarding trait anger—a negative affect associated with approach motivation—tended to support to the motivational direction model over the valence model. We discuss the implications for future research on frontal asymmetry as a neurobiological trait underlying motivational direction.