Attentional Resources: The Role of Dopamine in the Prefrontal Cortex

Attentional Resources: The Role of Dopamine in the Prefrontal Cortex Michael Williams, Alexander R. Matthews, Catalin V. Buhusi Dept. of Psychology, Utah State University, Logan Utah, USA Abstract. When emotional distractors occur the brain automatically diverts attention to deal with them. While this is most often adaptive as an organism needs to respond to its environment to survive, it poses a problem for individuals with affective disorders like schizophrenia, PTSD, and ADHD where the distraction causes a diversion of an inordinate amount of attentional resources. One of the processes that is impaired by this attentional shift is the ability to time in the seconds to minutes range, referred to as interval timing. According to the Relative Time-Sharing model, distracters cause a shift in attentional resources from primary tasks, such as interval timing, towards the identification of a distractor. Previous studies in our lab have identified the prefrontal cortex as having a major role in re-allocation of attentional resources. Specifically, nomifensine, a dopamine-norepinephrine reuptake inhibitor, helped rats divert attention from a distractor paired with footshock to timing when infused in prefrontal cortex (Matthews et al., 2012). In this pilot study we continued to investigate dopaminergic effects within the prefrontal cortex. Two groups of rats, Group 1 (n=4) and Group 2 (n=3) were exposed to a noise stimulus paired with foot shock; the noise was later used as an emotional distracter. Analyses of the delays caused by the sound showed a significant difference between groups under dopaminergic manipulations. This suggests that the prefrontal cortex is involved in re-allocation of attentional resources to timing when emotional distractors are presented, and that dopamine plays a role in modulating performance. Therefore, the role of dopamine in re-allocation of attentional resources warrants further investigation