Personality, psychopathology and brain oscillations

The associations among personality and psychopathology scores and individually adjusted EEG spectral power measures were investigated in 195 Ss aged 7 to 37 years. Personality was assessed in Ss older than 11 years by questionnaires based on Eysenckʹs and Grayʹs models. Psychopathology was measured in children aged 7–17 years by the Strengths and Difficulties Questionnaire (SDQ) and the Child Behaviour Check List (CBCL) completed by teachers, parents and children older than 11 years. EEG was recorded in a resting state. Absolute and relative spectral powers were calculated for individually adjusted delta, theta, and alpha bands. In order to test Robinsonʹs theory ([Robinson, 2001]), which states that the thalamocortical "alpha" system exerts an inhibitory effect over the brainstem "delta" system and that the strength of this inhibition relates to personality, Robinsonʹs analysis of averaged evoked potentials (AEP) was replicated on spontaneous EEG measures and an "Inhibition" score extracted. Extraversion, Behavioural Activation, and Conduct Problems were positively related to delta, and negatively related to alpha power and "Inhibition". Neuroticism, Behavioural Inhibition, and Emotional Symptoms showed an opposite pattern of correlations, being positively related to alpha and "Inhibition", and negatively related to delta power. These relationships generally support Robinsonʹs theory.