title: Reward Anticipation Is Encoded Differently by Adolescent Ventral Tegmental Area Neurons.
abstract: Elucidating the neurobiology of the adolescent brain is fundamental to our understanding of the etiology of psychiatric disorders such as schizophrenia and addiction, the symptoms of which often manifest during this developmental period. Dopamine neurons in the ventral tegmental area (VTA) are strongly implicated in adolescent behavioral and psychiatric vulnerabilities, but little is known about how adolescent VTA neurons encode information during motivated behavior.
  
  
  
  We recorded daily from VTA neurons in adolescent and adult rats during learning and maintenance of a cued, reward-motivated instrumental task and extinction from this task.
  
  
  
  During performance of the same motivated behavior, identical events were encoded differently by adult and adolescent VTA neurons. Adolescent VTA neurons with dopamine-like characteristics lacked a reward anticipation signal and showed a smaller response to reward delivery compared with adults. After extinction, however, these neurons maintained a strong phasic response to cues formerly predictive of reward opportunity.
  
  
  
  Anticipatory neuronal activity in the VTA supports preparatory attention and is implicated in error prediction signaling. Absence of this activity, combined with persistent representations of previously rewarded experiences, may provide a mechanism for rash decision making in adolescents.
authors.affiliation: Department of Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Yunbok
authors.initials: Y
authors.lastname: Kim
authors.affiliation: Department of Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Nicholas W
authors.initials: NW
authors.lastname: Simon
authors.affiliation: Department of Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Jesse
authors.initials: J
authors.lastname: Wood
authors.affiliation: Department of Neuroscience, University of Pittsburgh, Pittsburgh, Pennsylvania.. Electronic address: bita@pitt.edu.
authors.forename: Bita
authors.initials: B
authors.lastname: Moghaddam
mesh_terms: D000200:Action Potentials; D000818:Animals; D059031:Anticipation, Psychological / Q000502:physiology*; D001288:Attention / Q000502:physiology; D003216:Conditioning, Operant / Q000502:physiology; D003463:Cues; D004567:Electrodes, Implanted; D005108:Extinction, Psychological / Q000502:physiology; D008297:Male; D009042:Motivation / Q000502:physiology; D009474:Neurons / Q000502:physiology*; D017207:Rats, Sprague-Dawley; D012201:Reward; D017557:Ventral Tegmental Area / Q000254:growth & development* / Q000502:physiology*
keywords: Adolescent; Dopamine; Extinction; Instrumental learning; Reward; Ventral tegmental area