How personality modulates brain responses to emotion in music : a regions-of-variance approach

Background: Personality is related to emotional tendencies, and emotion is an important part of musical experiences. In particular, the personality traits Extraversion and Neuroticism have been respectively related to positive and negative emotionality (Larsen & Ketelaar, 1991) and to neural responses to positive and negative emotional stimuli (e.g., Canli et al., 2001). Openness to Experience is not characterized by affective tendencies, but it has been related aesthetic sensitivity (Costa Jr & McCrae, 1992) and to the intensity of music-induced emotions (Vuoskoski & Eerola, 2011a). Research on the role of Extraversion and Neuroticism in neural responses to emotion in music has given some null (Koelsch, Skouras, & Jentschke, 2013) and unexpected findings (Park et al., 2013); this research may be extended with different methodological choices, particularly with a larger sample size and with a method of selecting Regions of Interest (ROIs) that is intended for investigating individual differences in brain function (Omura et al., 2005). Aims: (1) To investigate the role of Extraversion, Neuroticism, and Openness to Experience in brain activations during implicit perception of emotions in music, and (2) to implement a data-driven method of selecting regions of interest as regions of variance (ROV; Omura et al., 2005). Hypotheses: It was predicted that Extraversion and Neuroticism would be related to brain activity during perception of positively- and negatively-valenced musical stimuli, respectively. The investigation of Openness was exploratory as this trait is not characteristically related to affect. No specific hypotheses were tested with regards to brain areas, as the method for selecting regions of interest was data-driven. Methods: Fifty-five participants were scanned using functional Magnetic Resonance Imaging while they listened to thirty, 4-second music excerpts portraying happiness, sadness, or fear, and they were asked to indicate the number of instruments following each excerpt. The Big Five Questionnaire (John & Srivastava, 1999) was used to measure personality traits. Regions of interest were selected as clusters of voxels with higher between-subjects variance in activation, relative to the mean within-subjects residual variance in activation, and a whole-brain voxelwise analysis additionally run for comparison. Results: In the ROV analysis, Neuroticism was positively related to activation during Sad music in the left supramarginal and angular gyri (p<.001, corrected), and Openness was positively related to activation during Happy music in the region of the left superior temporal gyrus, extending into the temporal pole, middle temporal gyrus, Heschl’s gyrus, postcentral gyrus, supramarginal gyrus, and rolandic operculum (p<.05, corrected). In the whole-brain analysis, similar results were found for Neuroticism but not for Openness. Discussion: These results support previous findings of trait-congruent links between personality and neural responses to emotional stimuli. Additionally, they indicate the usefulness of the ROV method for investigating individual differences; the ROV analysis was consistent with the robust whole-brain results and was additionally sensitive to clusters that did not survive whole-brain correction for multiple comparisons.