[Examination of decision-making processes in patients with traumatic brain injury].

INTRODUCTION Patients with moderate or severe traumatic brain injury (TBI) may show impairment in decision- making processes. The Iowa Gambling Task (IGT) has become a widely used neuropsychological research tool to investigate decision-making by simulating real-life decision-making in terms of uncertainty, reward, and punishment. OBJECTIVE Investigate decision-making in patients with moderate or severe TBI during performance of the IGT, and study patient's conscious knowledge of the task's reinforcement contingencies (reward/punishment schedule). PATIENTS AND METHODS Forty patients with moderate or severe TBI and 30 healthy volunteers participated in the study. Decision-making was evaluated using a computerized version of the IGT. After completing the task, the participants' knowledge of the task was tested. RESULTS The TBI group had worse performance on the IGT than the control group. They chose more unfavorable cards of the deck than the favorable ones. IGT score differences were observed among TBI patients in relation to level of knowledge of the task. The patients with knowledge of the task's reinforcement contingencies showed better performance, while the patients with scarce knowledge presented worse performance. CONCLUSIONS These results suggest that there is a direct relationship between the knowledge that patients with moderate and serious TBI have regarding the TBI reinforcement contingencies and their performance in the task.