Abstract. Concealing memories and emotions associated with a traumatic event seems to have negative effects on health. Re-enacting those events through writing is an opportunity to disclose such memories and emotions, and especially for emotion regulation. To study this, 57 university students were randomly assigned to one of two groups. They either completed an expressive writing or a neutral writing task. Real-time writing and psychophysiological data were recorded throughout the experiment to examine writing dynamics associated with emotion regulation and its psychophysiological correlates (electrodermal activity and electrocardiography measures). The results showed that the expressive group (EG) paused for longer than the control group (CG) denoting a positive and medium effect size [Formula: see text]. Furthermore, during and after writing, the EG showed a higher low frequency/high frequency ratio than the CG, evidencing a positive and large effect size [Formula: see text]. These real-time findings are interpreted as signs of emotion regulation happening during writing.