The biological basis of openness to experience

This thesis presents data that examines patterns of brain electrophysiology associated with Openness to Experience. Through reviewing the construct of Openness to experience a model is proposed whereby Openness is linked to associated measures of creativity, absorption, intelligence and emotional intelligence. By drawing on previous research into the neurobiology of these associated processes, a specific neurobiological model of Openness is proposed which implicated the dorsolateral prefrontal cortex (PFC), anterior cingulated (ACC), the temporal lobes and the mescocorticolimbic dopamine system. On the basis of this model a number of predictions are made in relation to expected electrophysiological patterns associated with Openness. In order to test the predictions of this model specific audio visual activation stimuli are developed with the aim of eliciting cognitive and affective processes associated with Openness. Evidence of the validity of these activation stimuli is presented through correlations between Openness and ratings of emotional arousal for the stimuli. Using a current Australian adult sample psychometric and behavioural data is collected using NEO PI-R Openness, WASI intelligence, SUEIT emotional intelligence, TAS Absorption, the Abbreviated Torrance Test for Adults (ATTA) and a newly devised creative behaviour checklist. 64-channel EEG is recorded both during a resting state and through the presentation of the activation stimuli. Power spectral measures are calculated according to individualized frequency bands at rest, while tonic induced ERBP and Phasic Evoked and Phasic Induced ERDS is calculated in response to the activation stimuli. Coherence analysis is also conducted for both the resting state and activation stimuli. The main findings of the study include increased upper alpha power associated with Openness to Ideas and decreased beta and gamma power associated with Openness to Fantasy during a resting state. Increased functional connectivity in the beta1 range was also found to be associated with Openness during a resting state. In relation to the activation stimuli, tonic induced ERBP was found to be associated with decreased delta power, particularly in the right anterior region. Openness was also found to be associated with greater frontal connectivity as well as greater inter-hemispheric and intra-hemispheric long distance coherence both in a resting state and during the activation tasks, particularly in relation to the beta1 frequency range. Openness was also found to be associated with decreased coherence in the theta range. Openness to Fantasy and Openness to Ideas formed the largest number of negative correlations with Openness to Fantasy found to be associated with disconnection between right fronto temporal regions and occipito-parietal regions bilaterally while Openness to Ideas was found to be associated with a more diffuse pattern of disconnection. The present findings are discussed in relation to the proposed neurobiological model of Openness and directions for future research are outlined.