To investigate which neuronal correlates underlie cortisol-induced enhancement of memory retrieval in PTSD and BPD.

The investigators have recently shown that hydrocortisone enhances rather than impairs memory retrieval in patients with posttraumatic stress disorder (PTSD) and borderline personality disorder (BPD). In contrast, in healthy participants memory retrieval was impaired after hydrocortisone compared to placebo.

The proposed studies aim to further investigate these findings and to understand the underlying neuronal correlates. Thus, the mechanisms of enhanced memory retrieval after hydrocortisone in patients with BPD and PTSD will be investigated by fMRI.

In a placebo-controlled study, the effects of 10mg hydrocortisone on brain activity, in particular the hippocampus, will be investigated in patients with PTSD and BPD and will be compared with those in healthy control participants. During the fMRI session, a declarative memory task (retrieval of a previous learned word list) and an autobiographical memory test will be performed. Effects of hydrocortisone on resting state brain activity and the neuronal correlates of memory retrieval will be analysed.

Inclusion Criteria:

• Clinical diagnosis of Borderline Personality Disorder
• Clinical diagnosis of PTSD
• females without psychiatric disorders as control group
• right handed

Exclusion Criteria:

• fMRI exclusion criteria e.g. metal implants, pregnancy, left-handedness, and claustrophobia.