title: Delay activity in avian prefrontal cortex--sample code or reward code?
abstract: In the current study, we examined whether delay activity in the avian equivalent of the prefrontal cortex (PFC) represents a neural correlate of a to-be-remembered sample stimulus or an upcoming reward. Birds were trained on a directed forgetting paradigm in which sample stimuli (red and white) were either followed by a cue to remember (high-frequency tone) or a cue to forget (low-frequency tone). The task also incorporated a differential outcomes procedure in which a correct response on the memory test following a red (remember) sample was rewarded with food, but correct responses on the memory test following the white (remember) sample were not. If delay activity represents a sample code, then it should be seen on both red-remember and white-remember trials. On the other hand, if delay activity represents a reward code, then delay activity should be seen only on red-remember trials, but not white-remember trials. Our findings suggest that activity in the avian PFC represents the outcome associated with each sample (reward or no reward) rather than memory for the sample itself.
authors.affiliation: Department of Psychology, University of Otago, Dunedin, New Zealand.
authors.forename: Rebecca
authors.initials: R
authors.lastname: Browning
authors.forename: J Bruce
authors.initials: JB
authors.lastname: Overmier
authors.forename: Michael
authors.initials: M
authors.lastname: Colombo
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D010856:Columbidae / Q000033:anatomy & histology / Q000502:physiology*; D004193:Discrimination Learning / Q000502:physiology*; D008568:Memory / Q000502:physiology*; D009474:Neurons / Q000166:cytology / Q000378:metabolism; D017397:Prefrontal Cortex / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D012201:Reward