Modulación del procesamiento cerebral por la magnitud de la recompensa en tareas de control cognitivo en participantes sanos y adictos a la cocaína

Resum

Reward contingencies increase the likelihood of a behavior and the brain processes necessary to perform them in addition to optimizing both behavior and brain processes. This doctoral thesis studies the effect of monetary reward magnitude on brain processing during goal-directed behaviors considering individual differences in personality and cocaine addiction. We performed three studies with monetary contingencies of variable magnitude during the execution of inhibition tasks in healthy participants and cocaine addicts. In both groups, the monetary reward produced a behavioral improvement proportional to the magnitude. In addition, in healthy participants this behavioral improvement was associated with the individual differences in sensitivity to reward. However, cocaine addicts showed deficient prefrontal modulation that counteracted with a greater involvement of occipital areas, an increased fronto-striatal connectivity and the left frontoparietal network.