Traumatic stress is linked to a deficit in associative episodic memory

Individuals with posttraumatic stress disorder (PTSD) are haunted by persistent memories of the trauma, but ironically are impaired in memories of daily life. The current set of 4 experiments compared new learning and memory of emotionally neutral content in 2 groups of patients and aged- and education-matched controls: 20 patients diagnosed with chronic posttraumatic stress disorder (C-PTSD) and 20 patients diagnosed with acute stress disorder (ASD). In all experiments, participants studied a list of stimuli pairs (words or pictures) and were then tested for their memory of the items, or for the association between items in each pair. Results indicated that both types of patients showed associative memory impairment compared to a control group, although their item memory performance was relatively intact. Potential mechanisms underlying such associative memory deficits in posttraumatic patients are discussed.