Motivation and the brain: How do appetitive versus aversive states relate to electroencephalographic activity?

Approach and Avoidance motivation are two of the oldest psychological concepts of behavior. Whereas approach motivation corresponds to the strong urge to come close to an object, state or person (e.g., during states of sexual attraction), avoidance motivation corresponds to the strong urge to avoid a specific situation (e.g., evade a dangerous situation). This dissertation deals with the electroencephalographic (EEG) markers of approach and avoidance motivation, assessed using event-related-potentials and brain oscillations in a low frequency band (alpha band). The first manuscript shows a left hemispheric processing advantage for approach-related stimuli. Specifically, we report a reduction in the alpha band (as an inverse maker for cortical activity) for erotic, but not for control pictures. Notably, we are the first to report alpha-asymmetries using an event-related design. In the second manuscript we describe evidence (a) for separating approach motivation from the affective dimensions of valence and arousal and (b) for an enhanced attention-related early EEG amplitude (P1 component) only for approach-related but not for control pictures. Up to our knowledge, we are the first to associate the P1 component with approach motivation. In the third manuscript we report an enlarged P1 component for increased avoidance motivation, as measured by the negative affect scale of the German Positive and Negative Affect Schedule (PANAS; Krohne, Egloff, Kohlmann, & Tausch, 1996). In more detail, state negative affect correlated positively with the P1 component, as a marker of increased selective attention. As far as we know, no study ever showed that state negative affect has an influence on attention. Therefore, we consider these findings regarding previous findings on trait negative affect, specifically on anxiety and phobia. All findings are discussed in the context of established views and models, such as Personality Systems Interaction (PSI) theory, hypervigilance theory, wanting versus liking and are also integrated into the findings from neuroimaging studies