Processing of self-related kinematic information embedded in static handwritten characters

• Self-, relative to non-self-, written characters reduced right posterior P250.
• Self-, relative to non-self-, written characters enhanced anterior midline LPC.
• ERP modulations were observed even when characters were stylized forms.
• ERP modulations were observed even when characters were written for the first time.
• Static self-written characters induce bodily-self and self-referential processing.

Handwritten characters are generated by our own motor actions, and previous studies have shown that the manner in which such characters are perceived and generated is related. However, the temporal course of the neural activation involved in the processing of self-related kinematic information embedded in static handwritten characters remains to be identified. We applied event-related potential (ERP) recording while participants judged whether handwritten characters were self- or non-self-generated. To test the effects of the self-related kinematic characteristics of static handwritten characters, we conducted two experiments in which the styles or familiarity of characters were manipulated. The ERP results indicated differences in brain activation between self- and non-self-written characters for the P250 component (250–350 ms after stimulus onset) in right posterior regions and for the late positive component (LPC; 350–500 ms after stimulus onset) in anterior midline regions; this was the case even when the handwritten characters were not generated in their usual form or were written for the first time. Therefore, our data indicate that self-information embedded in handwritten characters involves both right-lateralized brain activation associated with bodily self-processing and anterior midline brain activation related to self-referential processing.