Impact of pre-injury factors on outcome after severe traumatic brain injury: Does post-traumatic personality change represent an exacerbation of premorbid traits?

Although personality change is a frequent and disabling consequence of severe degrees of traumatic brain injury (TBI), little information is available beyond descriptive statements. The present paper presents a brief overview of the literature on the effects of pre-injury variables on post-trauma psychosocial functioning, and makes specific examination of the effect of premorbid personality structure on the post-trauma personality in people with TBI. A close relative of 28 people undergoing rehabilitation after TBI completed the Eysenck Personality Questionnaire Revised (EPQ-R) and Current Behaviour Scale (CBS) regarding the injured person's personality and character. Data were collected on three occasions: Ratings about premorbid status were taken as soon as feasible after admission, and follow-up ratings regarding current status were made at 6and 12 months post-trauma. As a group, premorbid ratings indicated an unremarkable profile on the EPQ-R. Significant changes had occurred by 6months post-trauma, which were sustained at 12 months post-trauma for both the EPQ-R and CBS. Yet none of the specific hypotheses regarding premorbid personality structure on the EPQ-R and post-trauma characterological deficits on the two CBS factors, Loss of Emotional Control (LEC) and Loss of Motivation (LM), was supported: There were no significant differences between subgroups with high or low premorbid levels of Extraversion, Neuroticism, Psychoticism, Addiction and Criminality and post-trauma CBS factors, LEC, and LM. These findings suggest that although personality changes occur as a result of traumatic brain injury, they are largely independent of the premorbid personality structure.