Alterations of the task-set reconfiguration process in closed head injury adolescents

The cost of shifting tasks across consecutive trials was examined as a func tion of the time interval between a task-cue and a subsequent target (cue-t o-target interval, CTI). Task-shift costs are assumed to index a process by which subjects reconfigure their task-set when they must perform different tasks across consecutive trials. In neurologically intact teenagers, incre ased CTI causes reduced task-shift costs since subjects have more time to r econfigure their task-set prior to target onset. Some closed head injury ad olescents however, show no reduction of task-shift costs with increased CTI . This indicates that subjects are incapable of reconfiguring their task-se t from the cue alone, they also require the target before they are able to initiate this reconfiguration. (C) 2000 Academic Press.