Frontal alpha asymmetry as a marker of approach motivation? Insights from a cooperative forking path analysis.

Frontal alpha asymmetry has been proposed as a ubiquitous marker of state and trait approach motivation, but recent meta-analyses found weak or nonexistent links with personality traits. It has been suggested that frontal asymmetry may show stronger individual differences in situations that elicit approach motivation (state-trait interaction). To investigate this with sufficient statistical power, we utilized data from the CoScience project (N = 740). Frontal asymmetry was measured during a resting period, a picture viewing task, and a guessing task, which were expected to trigger different levels of approach motivation. Results showed that frontal asymmetry was not reliably affected by task manipulations and did not relate to self-reported traits. Furthermore, Bayesian statistics and a cooperative forking path analysis were used to supplement the preregistered analyses. To conclude, this comprehensive analysis could not support the validity of frontal asymmetry as a marker of approach motivation, neither as a reliable state nor as a trait marker. (PsycInfo Database Record (c) 2025 APA, all rights reserved).