title: Behavioral flexibility is increased by optogenetic inhibition of neurons in the nucleus accumbens shell during specific time segments.
abstract: Behavioral flexibility is vital for survival in an environment of changing contingencies. The nucleus accumbens may play an important role in behavioral flexibility, representing learned stimulus-reward associations in neural activity during response selection and learning from results. To investigate the role of nucleus accumbens neural activity in behavioral flexibility, we used light-activated halorhodopsin to inhibit nucleus accumbens shell neurons during specific time segments of a bar-pressing task requiring a win-stay/lose-shift strategy. We found that optogenetic inhibition during action selection in the time segment preceding a lever press had no effect on performance. However, inhibition occurring in the time segment during feedback of results--whether rewards or nonrewards--reduced the errors that occurred after a change in contingency. Our results demonstrate critical time segments during which nucleus accumbens shell neurons integrate feedback into subsequent responses. Inhibiting nucleus accumbens shell neurons in these time segments, during reinforced performance or after a change in contingencies, increases lose-shift behavior. We propose that the activity of nucleus shell accumbens shell neurons in these time segments plays a key role in integrating knowledge of results into subsequent behavior, as well as in modulating lose-shift behavior when contingencies change.
authors.affiliation: Okinawa Institute of Science and Technology Graduate University, Neurobiology Research Unit, Onna-son, Japan 904-0495.
authors.forename: Luca
authors.initials: L
authors.lastname: Aquili
authors.forename: Andrew W
authors.initials: AW
authors.lastname: Liu
authors.forename: Mayumi
authors.initials: M
authors.lastname: Shindou
authors.forename: Tomomi
authors.initials: T
authors.lastname: Shindou
authors.forename: Jeffery R
authors.initials: JR
authors.lastname: Wickens
mesh_terms: D000818:Animals; D003657:Decision Making / Q000502:physiology*; D056344:Executive Function / Q000502:physiology*; D025461:Feedback, Physiological / Q000502:physiology; D030141:Feedback, Psychological / Q000502:physiology; D005822:Genetic Vectors; D025602:Halorhodopsins / Q000235:genetics / Q000378:metabolism; D008564:Membrane Potentials / Q000502:physiology; D009042:Motivation / Q000502:physiology; D009043:Motor Activity / Q000502:physiology; D009433:Neural Inhibition; D009474:Neurons / Q000502:physiology*; D009483:Neuropsychological Tests; D009714:Nucleus Accumbens / Q000502:physiology*; D062308:Optogenetics; D011597:Psychomotor Performance / Q000502:physiology*; D051381:Rats; D020318:Rats, Long-Evans; D012193:Reversal Learning / Q000502:physiology; D012201:Reward; D013997:Time Factors
chemical_list: D025602:Halorhodopsins