Emotional valence and arousal affect reading in an interactive way: neuroimaging evidence for an approach-withdrawal framework.
A growing body of literature shows that the emotional content of verbal material affects reading, wherein emotional words are given processing priority compared to neutral words. Human emotions can be conceptualised within a two-dimensional model comprised of emotional valence and arousal (intensity). These variables are at least in part distinct, but recent studies report interactive effects during implicit emotion processing and relate these to stimulus-evoked approach-withdrawal tendencies. The aim of the present study was to explore how valence and arousal interact at the neural level, during implicit emotion word processing. The emotional attributes of written word stimuli were orthogonally manipulated based on behavioural ratings from a corpus of emotion words. Stimuli were presented during an fMRI experiment while 16 participants performed a lexical decision task, which did not require explicit evaluation of a word's emotional content. Results showed greater neural activation within right insular cortex in response to stimuli evoking conflicting approach-withdrawal tendencies (i.e., positive high-arousal and negative low-arousal words) compared to stimuli evoking congruent approach vs. withdrawal tendencies (i.e., positive low-arousal and negative high-arousal words). Further, a significant cluster of activation in the left extra-striate cortex was found in response to emotional than neutral words, suggesting enhanced perceptual processing of emotionally salient stimuli. These findings support an interactive two-dimensional approach to the study of emotion word recognition and suggest that the integration of valence and arousal dimensions recruits a brain region associated with interoception, emotional awareness and sympathetic functions.
Cluster of Excellence "Languages of Emotion", Freie Universität Berlin, Habelschwerdter Allee 45, D-14195 Berlin, Germany. Electronic address: fmm.citron@gmail.com.
Francesca M M
FM
Citron
Centre for Advanced Imaging, The University of Queensland, Australia; Psychiatry, Brighton & Sussex Medical School, Universities of Brighton and Sussex, UK.
Marcus A
MA
Gray
Psychiatry, Brighton & Sussex Medical School, Universities of Brighton and Sussex, UK; Sussex Partnership NHS Foundation Trust, Brighton, UK; Sackler Centre for Consciousness Science, University of Sussex, UK.
Hugo D
HD
Critchley
Laboratory for Communication Science, The University of Hong Kong, China.
Brendan S
BS
Weekes
Center for Cognitive Science, Albert-Ludwigs-Universität Freiburg, Germany.
Evelyn C
EC
Ferstl
D000293:Adolescent; D000328:Adult; D000704:Analysis of Variance; D001143:Arousal / Q000502:physiology*; D002540:Cerebral Cortex / Q000098:blood supply*; D004644:Emotions / Q000502:physiology*; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted; D008279:Magnetic Resonance Imaging; D008297:Male; D010100:Oxygen / Q000097:blood; D011930:Reaction Time / Q000502:physiology; D011932:Reading; D012660:Semantics; D014825:Vocabulary; D055815:Young Adult
D010100:Oxygen
Approach; Arousal; Emotional words; Valence; Withdrawal; fMRI