PhD defence C.S. (Carmen) Sergiou

Dissertation in short:

Aggressive behavior is still a major problem in society. The brain processes underlying aggressive behavior and the prediction of this behavior are crucial for treatment in forensic care. Nevertheless, current treatment options within forensic care often seem insufficient to reduce aggressive behavior and violent recidivism. Therefore, the interest towards innovative interventions in neuroscience has increased. Using neuroscience, diminished brain activity and deficits of the brain in relation to aggressive behavior can be investigated. A promising add-on treatment option is the use of transcranial Direct Current Stimulation (tDCS). This is a technique to modulate brain regions of interest to enhance brain activity.

This dissertation explored the effects of High-Definition (HD)-tDCS in a forensic sample with a violent offence to see whether empathic abilities could be enhanced and subsequent aggression could be reduced. Furthermore, this dissertation investigated the behavioral and neurophysiological measures of aggression and empathy to get a better insight into the effects of tDCS in the treatment of forensic patients. To examine these aims we studied the effect of using multiple session HD-tDCS in a forensic sample using electroencephalography (EEG), self-report questionnaires and tasks measuring empathy and aggression. The results described in this dissertation demonstrated that reactive aggression both using a laboratory task and a self-report questionnaire can be reduced after a week of intervention. In addition, we demonstrated the effectiveness of tDCS in modulating electrophysiological responses.
The conclusion of this dissertation is that HD-tDCS seems to be an effective intervention to reduce aggressive behavior and modulate electrophysiological responses. Although this is a proof-of-concept study, the findings contribute to a better understanding of the aggressive brain and the implementation of using HD-tDCS as an add-on therapy in forensic care.