Risky economic choices and frontal EEG asymmetry in the context of Reinforcer-Sensitivity-Theory-5.

This study investigated individual risky choice behavior in a gambling task and its relation with traits proposed by the Reinforcer-Sensitivity-Theory-5 (RST-5; Corr & McNaughton in Neuroscience and Biobehavioral Reviews, 36(10), 2339-2354, 2012) as well as with frontal EEG asymmetry. As assumed by the RST-5, the results showed independent influences of approach/avoidance and gain/loss sensitivities on participants' behavior in risky choices. Individual approach/avoidance sensitivity was predicted by trait measures of the behavioral approach system (BAS) and the behavioral inhibition system (BIS), while no such correlation was present for gain/loss sensitivity. EEG recordings revealed relatively stronger left-frontal cortical activity for trials with approach motivation compared to conflict and avoidance motivation. On the individual level, relatively stronger left-frontal cortical activity was associated with trait BAS. In addition, activity changes in frontal EEG asymmetry were associated relatively higher behavioral approach sensitivity. We conclude that frontal EEG asymmetry is an especially useful neuronal marker of BAS sensitivity and that the traits proposed by the RST-5 (measured by frontal EEG asymmetry and self-report) can be used to explain individual differences in risky choice behavior.