Life Events, Frontal Electroencephalogram Laterality, and Functional Immune Status after Acute Psychological Stressors in Adolescents

OBJECTIVE: Past studies have found that environmental stress affects cellular immune function and that extensive variability exists in the magnitude and direction of stress-induced immune changes. Past research also suggests that individuals with greater right, relative to left, resting frontal electroencephalogram (EEG) activation perceive environmental stress as more aversive and have lower baseline cellular immune function. In this study, we examined environmental stressors, resting frontal EEG laterality, and immune responses to short-term psychological stressors in adolescent boys. METHODS: A sample of twenty-four 14-16 year old right-handed boys underwent a recording of resting EEG and collections of blood taken before and after a laboratory protocol designed to induce psychological stress. Blood samples were used to measure changes in mitogen lymphoproliferative responses, natural killer (NK) cell activity, and T-cell phenotypic subsets. Life events were measured using self-report questionnaires. RESULTS: Life events and frontal laterality showed a first order interaction in predicting changes in lymphocyte proliferation to tetanus toxoid (R2 increment = .26, p < .01) and pokeweed mitogen (R2 increment = .25, p < .02). The interaction also predicted changes in NK activity (R2 increment = .24, p < .02). CONCLUSIONS: Changes in lymphocyte proliferation and NK activity were associated with negative life events only among individuals with greater left frontal cortical activation. Our results suggest that recent psychosocial stress and individual differences in resting frontal cortical activation are together linked to immunologic responses to acute psychological stressors.