Abstract: Objective To explore the impulse control and event-related potential （ERP） characteristics of patients with mental disorders caused by traumatic brain injury （TBI） in forensic psychiatry identification and to provide objective auxiliary indicators for forensic psychiatry identification. Methods Thirty patients （TBI group） with mental disorders caused by traumatic brain injury, who were identified as mild psychiatric impairment by judicial psychiatry, including 24 males and 6 females, as well as the thirty people in the control group participated in the study. All the participants completed Barratt Impulsiveness Scale-11 （BIS-11） and ERP induced by Go/NoGo tasks. BIS-11 and ERP data were collected and analyzed. Results The results of the BIS-11 showed that the total score and subscale scores of the TBI group were higher compared to the control group （P<0.05）. Moreover, the TBI group exhibited significantly lower NoGo-N2 amplitude and lower NoGo-P3 amplitude than the control group. The NoGo-N2 amplitude was larger than the Go-N2 amplitude, and the NoGo-P3 amplitude was larger than the Go-P3 amplitude in both groups （P<0.05）. Conclusion Traumatic brain injury could impair impulse control of mild psychiatric impairment patients, and the amplitudes of NoGo-N2 and NoGo-P3 could be important parameters to evaluate the impulse control of patients with mental disorders caused by traumatic brain injury.

Key words: forensic psychiatry, mental disorders, brain injuries, impulse control disorders, event-related potentials, Go/NoGo task, Barratt Impulsiveness Scale-11