Introduction

Most people who suffer serious traumatic brain injury (TBI) have a period of loss of consciousness and post-traumatic amnesia that typically means that they do not recall the moment of injury itself. They may also have a gap in memory stretching from some time prior to injury to some time after the injury. Therefore despite going through the traumatic experience of a motor vehicle accident or assault or fall the individual may have no recollection of the incident itself. Post-traumatic stress disorder (PTSD) is a mood disorder characterized by re-experiencing (flashbacks, nightmares), avoidance and arousal symptoms (e.g. hypervigilance) in relation to having experienced, witnessed or been confronted by an event involving death or serious injury that results in feelings of fear, helplessness or horror (American Psychiatric Association, 2000). In the context of amnesia for the traumatic event, the question as to whether PTSD can occur after TBI, has been the subject of some debate (Sbordone and Liter 1995; Bryant et al. 2000; Williams et al. 2002; Sumpter and McMillan 2006). However, it is generally accepted now that, through various different mechanisms, PTSD can occur after TBI (Bryant, 2001). Some people who suffer a closed head injury have partial recall of the incident (Creamer et al. 2005) with some experiencing specific ‘islands’ of memory for traumatic events (King, 1997).