title: Time context of cue-outcome associations represented by neurons in perirhinal cortex.
abstract: The perirhinal cortex (PRh), which has extensive connections with diverse brain sites, may contribute to semantic memory by associating various types of information about objects. However, the extent of the types of associations in which PRh participates is unknown. In the present study, we let monkeys experience a consistent contingency between visual cues and different types of outcomes (water reward and sound-only acknowledgment) in a particular time context for many days and then recorded neuronal activities from PRh and area TE, which is the major source of visual inputs to PRh. We found that PRh cells represented the outcome type in their responses to the visual cues only in the time context in which the monkeys had experienced the cue-outcome contingency. In contrast, TE cells represented the outcome information whenever the cue appeared (i.e., independently from the related time context). These results showed that PRh cells represented not only the cue-outcome contingency but also the time context in which the monkeys had experienced the contingency. We conclude that PRh is not specific to the representation of sensory and associative properties of objects themselves but may represent broader information about objects, including the time context in which the objects are associated with particular outcomes.
authors.affiliation: Cognitive Brain Mapping Laboratory, RIKEN Brain Science Institute, Saitama 351-0198, Japan, Graduate School for Science and Engineering, Saitama University, Saitama 338-8570, Japan, and.
authors.forename: Manoj Kumar
authors.identifier: http://orcid.org/0000-0003-3300-4772
authors.initials: MK
authors.lastname: Eradath
authors.affiliation: Cognitive Brain Mapping Laboratory, RIKEN Brain Science Institute, Saitama 351-0198, Japan.
authors.forename: Tsuguo
authors.initials: T
authors.lastname: Mogami
authors.affiliation: Cognitive Brain Mapping Laboratory, RIKEN Brain Science Institute, Saitama 351-0198, Japan, Department of Bioengineering, Faculty of Engineering, Kagoshima University, Kagoshima 890-0065, Japan.
authors.forename: Gang
authors.initials: G
authors.lastname: Wang
authors.affiliation: Cognitive Brain Mapping Laboratory, RIKEN Brain Science Institute, Saitama 351-0198, Japan, keiji@riken.jp.
authors.forename: Keiji
authors.initials: K
authors.lastname: Tanaka
mesh_terms: D000200:Action Potentials / Q000502:physiology*; D000704:Analysis of Variance; D000818:Animals; D001245:Association Learning / Q000502:physiology*; D001288:Attention / Q000502:physiology; D002540:Cerebral Cortex / Q000166:cytology*; D003463:Cues; D008253:Macaca mulatta; D008297:Male; D009474:Neurons / Q000502:physiology*; D010775:Photic Stimulation; D011930:Reaction Time; D012201:Reward
keywords: area TE; inferotemporal cortex; macaque monkey; reward