Integrative Assessment of Brain and Cognitive Function in Post-Traumatic Stress Disorder

Abstract

The present study combined neuropsychological and electrophysiological measures to obtain a comprehensive profile of the everyday attentional and memory dysfunction reported in PTSD. The event-related potential (ERP) literature has consistently found abnormalities in late components (N2, P3) reflecting working memory (WM) function. However, the neuropsychological profile reported in the literature has considerable variation. The present study examined ERP activity in 33 PTSD participants and matched controls during a standard two-tone auditory oddball task. Neuropsychological assessment was carried out using a task battery assessing a wide range of cognitive functions. Consistent with previous work, the PTSD group showed delayed N2 latency and reduced P3 target amplitude, together with slower and less accurate target detection. Scalp topography provided evidence of widespread abnormality during WM function, but with strongest effects broadly over the left hemisphere. Neuropsychological testing found concomitant difficulties on factorial measures of verbal memory retention/access and sustained attention but enhanced performance on measures of immediate recall. This integrative pattern of effects reflects a specific impairment in the operation of working memory systems that guide ongoing, planned behavior and that facilitate the acquisition and retention of new memories.

Neuropsychology and clinical neuroscience of persistent post-concussive syndrome

“…The same can be said about the co-occurrence of PTSD in those involved in accidental injury or assault as the source of their concussion (Bryant, 2001;Creamer et al, 2005;McCauley et al, 2001) and the role of stress hormones in the behavioral response to injury (Sojka et al, 2006). PTSD alone has its own unique effect on neuropsychological performance (Vasterling & Bremner, 2006;Veltmeyer et al, 2005). Even for those who do not develop PTSD, being in an accident (Mayou & Bryant, 2002) or an assault (Johansen et al, 2006) or just sustaining a brain injury (Prigatano et al, 2005) is stress producing.…”

Hydrocortisone reduces emotional distracter interference in working memory

“…For instance, PTSD is associated with prefrontal dysfunction (Beckham et al, 1998;Bremner, 2002Bremner, , 2006Hou et al, 2007) and activation abnormalities in the prefrontal cortex (PFC) during WM performance (Galletly et al, 2001;Clark et al, 2003;Veltmeyer et al, 2005;Moores et al, 2008). Patients with stress-related disorders are also very susceptible to emotional distraction and poor at suppressing trauma-related or other (emotionally arousing) thoughts and feelings, possibly due to impaired prefrontal functioning (McNally, 1998;Elzinga and Bremner, 2002;Williams and Moulds, 2007).…”

Enhanced Effects of Cortisol Administration on Episodic and Working Memory in Aging Veterans with PTSD

“…These neuroendocrine alterations in PTSD differ from those observed in major depression and normal aging, conditions that have been associated with reduced glucocorticoid responsiveness and increased cortisol levels (O'Brien et al, 1999;Sapolsky 2000;Lupien et al, 1999;Yehuda et al, 1996). The major cognitive decrements described in PTSD have involved performance on tests of episodic memory (Vasterling et al, 2002;Veltmeyer et al, 2005;Bremner et al, 1995;Yehuda et al, 1995). These deficits have implicated medial temporal circuits, particularly, the hippocampus, a region that has been shown to be responsive to glucocorticoids, involved in episodic memory, and manifesting structural and functional alterations in PTSD (Mirescu and Gould, 2006;Sauro et al, 2003;Het et al, 2005;Kitayama et al, 2005).…”