ABSTRACT For a number of years, there has been a wide-ranging interest in the biological basis of personality and temperament. However, few reliable biological markers of temperament have been identified. Recent research has shown that resting electroencephalographic (EEG) asymmetry recorded from frontal regions of the brain is a biological marker that predicts individual differences in emotional reactivity and in emotional traits. This research has shown that individuals characterized by relative activation of right hemisphere frontal regions have an increased predisposition for negative affect and a decreased predisposition for positive affect. The opposite pattern appears characteristic of individuals with relative left frontal activation. However, the research has left unclear precisely what predisposition are linked to frontal asymmetry. In addition, prior work has not linked anterior asymmetry to known functions mediated by the frontal lobes. On the basis of evidence concerning functions mediated by the frontal lobes and evidence concerning affective traits that are linked to anterior asymmetry, it is proposed that the critical predispositions linked to frontal asymmetry are individual differences in cognitive and related processes that serve to regulate or modulate emotional reactions or goal-directed performance on tasks that elicit significant emotion. It is hypothesized that relative left anterior activation promotes access to cognitive processes that serve to amplify or sustain positive affect and to inhibit or dampen negative affect. It is hypothesized that relative right anterior activation is linked to the opposite pattern. To test these hypotheses, four experiments will be conducted to assess the relation between resting frontal asymmetry and: 1. various components of a "state" vs "action" orientation in response to experimentally induced failure; 2. self-focused attentional responses to success and failure; 3. selective memory for affectively toned events; and 4. selective attention to affective stimuli. These studies will help elucidate the critical predispositions linked to resting frontal asymmetry and will have more general implications for models of the contribution of the cerebral cortex to individual differences in emotion-related personality traits. In addition, because few studies have assessed the relation between the prefrontal cortex and the regulation of emotion, the present studies will contribute to knowledge concerning the functions served by this clearly important, yet largely uncharted, region of the brain.
