The goal of the proposed research is to assess the role of the basolateral amygdala (BLA) and orbitofrontal cortex (OFC) in learning about changes in reward value. I will use two behavioral paradigms to address this issue. Outcome devaluation involves reducing reward value pairing its consumption with gastric illness, and delayed reward discounting reduces reward value by delaying its delivery. Comparing the effects of BLA or OFC lesions in these tasks will provide information about the types of reward learning that they support. This is relevant because human drug abusers exhibit decision-making impairments and impulsive choice, in addition to metabolic dysfunction of the OFC and BLA. Understanding how these brain regions are involved in learning about rewards will provide information about the processes disrupted in drug abusers.
| Helms, Christa M; Mitchell, Suzanne H (2008) Basolateral amygdala lesions and sensitivity to reinforcer magnitude in concurrent chains schedules. Behav Brain Res 191:210-8 |
| Helms, C M; Gubner, N R; Wilhelm, C J et al. (2008) D4 receptor deficiency in mice has limited effects on impulsivity and novelty seeking. Pharmacol Biochem Behav 90:387-93 |
| Helms, Christa M; Reeves, Jamie M; Mitchell, Suzanne H (2006) Impact of strain and D-amphetamine on impulsivity (delay discounting) in inbred mice. Psychopharmacology (Berl) 188:144-51 |
