Thesis defense Marijn Kroes (Donders Series 127)

5 September 2013

Promotors: Prof.dr. G. Fernandez and Prof.dr. B. Strange, copromotor: dr. G. van Wingen

Altering memories for emotional experiences

Emotional experiences are remembered well and allow optimal adjustment to our environment, but can also lead to traumatic memories, such as in the case of post-traumatic stress disorders (PTSD). Marijn Kroes investigated what changes in the brains of PTSD patients, what happens when they recall traumatic memories, and whether it is possible to permanently alter or even erase memories for emotional experiences. His research shows that both the structure and functioning of the brain in PTSD patients is compromised. Further, his work reveals that it is possible to erase memories for emotional experiences by disturbing the normal electrical activity of the brain following memory reactivation. In addition, it turns out that emotional memories can be permanently altered via blockade or activation of the chemicals noradrenaline and serotonins in the brain during the recall of emotional experiences or when learning to inhibit fear responses. These alterations of emotional memories are accompanied by functional changes in brain regions important for the regulation of emotions and these areas overlap with the abnormal brain functions in patients with PTSD. Marijn Kroes' research indicates that memories for emotional experiences can be permanently altered and provide important insights into the development of novel psychiatric treatment strategies.