Assessing the neural correlates of self-enhancement bias: a transcranial magnetic stimulation study

Considerable research has focused on overly positive self-perceptions (self-enhancement), and yet little is known about the underlying neural mechanisms. The present study sought to assess the neural correlates of self-enhancement by applying Transcranial Magnetic Stimulation (TMS) to three brain regions. Twelve participants rated their best friend, as well as the self on a set of desirable or undesirable traits while TMS pulses were delivered in a virtual lesion manner. During the baseline condition (Sham TMS), participants produced more desirable and fewer undesirable ratings for themselves as compared to their best friend, showing self-enhancement. Compared to Sham TMS, TMS delivered to the Medial Prefrontal Cortex (MPFC) reduced self-enhancement whereas TMS delivered to the Supplementary Motor Area (SMA) and the precuneus did not. Together, these findings suggest that the MPFC may influence self-enhancement.