A double-blind HD-tDCS/EEG study examining right temporoparietal junction involvement in facial emotion processing

ABSTRACT

Prior studies have demonstrated that aspects of social cognition can be modulated via temporoparietal junction (TPJ) transcranial direct current stimulation (tDCS). However, this technique lacks focality and electrophysiological effects or correlates are rarely examined. The present study investigated whether anodal and/or cathodal high-definition tDCS (HD-tDCS) would influence facial emotion processing performance relative to sham stimulation, and whether task performance changes were related to neurophysiological changes. Participants completed a facial emotion attribution tasks before and after rTPJ HD-tDCS, with event-related potentials (ERP) recorded during task performance. Anodal rTPJ HD-tDCS improved facial emotion processing performance for static depictions of fear (but not surprise). Stimulation condition influenced P300 latency, and also influenced the relationship between behavioural and electrophysiological (ERP) outcomes in several circumstances, findings which both support and challenge anodal-excitation/cathodal-inhibition accounts of tDCS effects. Results suggest that rTPJ anodal HD-tDCS can influence facial emotion recognition (i.e., affective mentalizing), and elucidate the nature and distribution of underlying neurophysiological processes. Stimulation effects, however, might depend on the intensity and salience/valence (negativity/threat) of the emotion, and these behavioural effects may not relate directly or simply to the ERPs assessed here.

KEYWORDS:

• HD-tDCS
• EEG
• TPJ
• temporoparietal junction
• social cognition

Acknowledgments

Peter Enticott is supported by a Future Fellowship from the Australian Research Council (ARC) (FT160100077). Nicole Rinehart receives funding from the Ferrero Group, Australia, as part of its Kinder + Sport pillar of Corporate Social Responsibility initiatives to promote active lifestyles among young people. Ferrero Group Australia had no role in this research including the collection, analysis, and interpretation of data; in writing of the manuscript; and in the decision to submit the article for publication. The authors would also like to thank Charlotte Davies and Natalia Albein-Urios, who contributed to data collection.

Disclosure statement

No potential conflict of interest was reported by the authors.

Supplemental material

Supplemental data for this article can be accessed here.

Additional information

Funding

This work was supported by the Australian Research Council [FT160100077];Ferrero Group