Social interaction and speed of information processing following very severe head-injury

Eighteen adults who had suffered a very severe closed head-injury more than 18 months previously and required long-term rehabilitative support were compared with a closely matched control group. Unlike previous studies, which have reported negative personality change involving an increase in aversive behaviour, our behavioural observation data suggest that a global reduction in behavioural productivity, or negative symptomatology, characterizes social interaction by this group. This resulted in their being judged less socially skilled, less likeable and less interesting, and thus less reinforcing to interact with. Speed of information processing was specifically impaired for the closed head-injury group, although this did not correlate with global behavioural ratings of social interaction behaviour. It is suggested that low behavioural productivity may be associated with family burden, and that the low quantity of social interaction experienced by severely head-injured adults may reflect the unreinforcing nature of their interactions.