The Neuropsychological Mechanisms of Avoidant Coping Post Traumatic Brain Injury

Many people who sustain traumatic brain injuries (TBI) have poor psychosocial outcomes. Previous research has indicated that poor outcomes are related to the use of avoidant coping following TBI, although the mechanisms of this relationship are not clear. The major pathological consequence of TBI is damage to the frontal lobes and/or their connections, resulting for most people in executive and/or affective dysfunction. The purpose of this dissertation study was to delineate the neuropsychological, psychiatric, personality and physiological mechanisms of avoidant coping following TBI. Controls and people with TBI completed the Baycrest Psychosocial Stress Test (BPST), where coping behaviour was observed directly, and physiological measures were recorded. Participants also completed a neuropsychological test battery, and a series of questionnaires assessing coping, psychiatric status, personality and outcomes. There were no significant differences between groups in self reported coping. However, the control and mild TBI group engaged in more planful than avoidant behaviour on the BPST. As a group, individuals with moderate-to-severe injury, in contrast, engaged in more avoidant than planful behaviour. However, analysis of individual differences in coping behaviour within the moderate-to-severe group revealed a bimodal distribution, allowing classification of people in this group as ‘planners’, or ‘avoiders’ (this distribution was not evident in the mild TBI group). Within the moderate-to-severe group, planners had better executive function, were more reactive to stress (psychologically and physiologically), performed better on the speech task during the BPST, and had greater return to productivity. However, planners also had worse psychosocial outcomes as compared to the avoiders. This was the first study, to the author’s knowledge, to examine coping behaviour during a simulated real-world stress test. Results indicate that behavioural measures of coping, such as the BPST, are more sensitive to changes in coping post TBI than are self and significant other reported questionnaires. Results also demonstrate that executive function and psychological and physiological reactivity are important factors that contribute to coping following moderate-to-severe TBI. These data raise important questions about the challenges of targeting coping through rehabilitation.Ph