Adaptive gain and the role of the locus coeruleus-norepinephrine system in optimal performance.
Historically, the locus coeruleus-norepinephrine (LC-NE) system has been implicated in arousal, but recent findings suggest that this system plays a more complex and specific role in the control of behavior than investigators previously thought. We review neurophysiological, anatomical, and modeling studies in monkey that support a new theory of LC-NE function. LC neurons exhibit two modes of activity, phasic and tonic. Phasic LC activation is driven by the outcome of task-related decision processes and is proposed to facilitate ensuing behaviors and to help optimize task performance. When utility in the task wanes, LC neurons exhibit a tonic activity mode, associated with disengagement from the current task and a search for alternative behaviors. Monkey LC receives prominent, direct inputs from the anterior cingulate (ACC) and orbitofrontal cortices (OFC), both of which are thought to monitor task-related utility. We propose that these prefrontal areas produce the above patterns of LC activity to optimize the utility of performance on both short and long time scales.
Aston-Jones
Gary
G
Laboratory of Neuromodulation and Behavior, Department of Psychiatry, University of Pennsylvania, Philadelphia, Pennsylvania 19104, USA. gaj@mail.med.upenn.edu
Cohen
Jonathan D
JD
D000223:Adaptation, Psychological / Q000502:physiology*; D000818:Animals; D002540:Cerebral Cortex / Q000502:physiology; D003071:Cognition / Q000187:drug effects / Q000502:physiology; D004298:Dopamine / Q000494:pharmacology / Q000502:physiology; D007858:Learning / Q000502:physiology; D008125:Locus Coeruleus / Q000502:physiology*; D009043:Motor Activity; D009638:Norepinephrine / Q000502:physiology*
D004298:Dopamine; D009638:Norepinephrine