Anterior cingulate neurons in the rat map anticipated effort and reward to their associated action sequences.
Goal-directed behaviors require the consideration and expenditure of physical effort. The anterior cingulate cortex (ACC) appears to play an important role in evaluating effort and reward and in organizing goal-directed actions. Despite agreement regarding the involvement of the ACC in these processes, the way in which effort-, reward-, and motor-related information is registered by networks of ACC neurons is poorly understood. To contrast ACC responses to effort, reward, and motor behaviors, we trained rats on a reversal task in which the selected paths on a track determined the level of effort or reward. Effort was presented in the form of an obstacle that was climbed to obtain reward. We used single-unit recordings to identify neural correlates of effort- and reward-guided behaviors. During periods of outcome anticipation, 52% of recorded ACC neurons responded to the specific route taken to the reward while 21% responded prospectively to effort and 12% responded prospectively to reward. In addition, effort- and reward-selective neurons typically responded to the route, suggesting that these cells integrated motor-related activity with expectations of future outcomes. Furthermore, the activity of ACC neurons did not discriminate between choice and forced trials or respond to a more generalized measure of outcome value. Nearly all neural responses to effort and reward occurred after path selection and were restricted to discrete temporal/spatial stages of the task. Together, these findings support a role for the ACC in integrating route-specific actions, effort, and reward in the service of sustaining discrete movements through an effortful series of goal-directed actions.
Neurosciences Institute, 10640 John Jay Hopkins Dr., San Diego, CA 92121, USA. cowen@nsi.edu
Stephen L
SL
Cowen
Glen A
GA
Davis
Douglas A
DA
Nitz
D000818:Animals; D059031:Anticipation, Psychological / Q000502:physiology*; D001931:Brain Mapping / Q000379:methods*; D006179:Gyrus Cinguli / Q000502:physiology*; D008297:Male; D009415:Nerve Net / Q000502:physiology*; D009474:Neurons / Q000502:physiology*; D011446:Prospective Studies; D051381:Rats; D017207:Rats, Sprague-Dawley; D012201:Reward