Exploring the impact of traumatic brain injury on moral reasoning and how this relates to executive functioning, empathy and emotion-based decision making.

Traumatic brain injury (TBI) leads to cognitive, behaviour, and social functioning difficulties. It has also been associated with offending behaviour. The common area of damage is to the fronto-temporal brain regions (Salmond et al, 2006). These are considered important for moral reasoning. Moral reasoning is believed to be important for upholding social function and preventing delinquent behaviour (Gibbs, 2010). It is suggested that TBI may disrupt moral reasoning and contribute to social and behaviour deficits (Anderson & Catroppa, 2006). Studies to date have indicated that there are greater difficulties in moral reasoning following a childhood TBI than adulthood TBI. Studies have been small and have not examined the impact of childhood TBI in early adulthood. Fewer studies have explored the neurocognitive processes underpinning moral reasoning. This study compared moral reasoning, measured by the Sociomoral Reflection Measure - Short Form (SRM-SF, Gibbs, Basinger & Fuller, 1992) in a group of 20 survivors of TBI aged between 17 and 25 years and a group of 34 healthy individuals. It also explored the relationships between moral reasoning and executive functions, cognitive flexibility, inhibition; empathy and emotion-based decision making. The healthy comparison group demonstrated significantly higher moral reasoning. This was maintained when the groups were matched on age, sex, socioeconomic status and when intellectual functioning was controlled. The study revealed significant relationships between moral reasoning and cognitive flexibility, inhibition, executive function difficulties and empathy in the healthy comparison group. Only one significant correlation was revealed in the TBI group; between cognitive flexibility and moral reasoning. This was attributed to insufficient power to detect other significant findings. The study concluded that TBI sustained during childhood does disrupt moral development. It also indicated that executive function processes and empathy may be involved iii in moral reasoning. These findings were considered in relation to theories of moral reasoning, brain development and methodological rigour. Further research is suggested