title: Responses of monkey prefrontal neurons during the execution of transverse patterning.
abstract: Recent functional imaging studies have suggested that the prefrontal cortex (PF) is engaged in the performance of transverse patterning (TP), which consists of 3 conflicting discriminations (A+/B-, B+/C-, C+/A-). However, the roles of PF in TP are still unclear. To address this issue, we examined the neuronal responses in 3 regions [the principal sulcus (PS), dorsal convexity (DC), and medial prefrontal cortex (MPF)] of the macaque PF during the performance of an oculomotor version of TP. A delayed matching-to-sample (DMS) task was used as a control task. The TP task-responsive neurons were most abundant in MPF. We analyzed the dependency of each neuronal response on the task type (TP or DMS), target shape (A, B, or C), and target location (left or right). Immediately after the choice cue presentation, many MPF neurons showed task dependency. Interestingly, some of them already exhibited differential activity between the 2 tasks before the choice cue presentation. Immediately before the saccade, the number of target location-dependent neurons increased in MPF and PS. Among them, many MPF neurons were also influenced by the task type, whereas PS neurons tended to show location dependency without task dependency. These results suggest that MPF and PS are involved in the execution of TP: MPF appears to be more important in the target selection based on the TP rule, whereas PS is apparently more related to the response preparation. In addition, some neurons showed a postsaccadic response, which may be related to the feedback mechanism.
authors.affiliation: Cognitive Neuroscience Section, Primate Research Institute, Kyoto University, Inuyama, Aichi 484-8506, Japan.
authors.forename: Masafumi
authors.initials: M
authors.lastname: Nejime
authors.affiliation: Cognitive Neuroscience Section, Primate Research Institute, Kyoto University, Inuyama, Aichi 484-8506, Japan.
authors.forename: Masato
authors.initials: M
authors.lastname: Inoue
authors.affiliation: Cognitive Neuroscience Section, Primate Research Institute, Kyoto University, Inuyama, Aichi 484-8506, Japan.
authors.forename: Masanori
authors.initials: M
authors.lastname: Saruwatari
authors.affiliation: Cognitive Neuroscience Section, Primate Research Institute, Kyoto University, Inuyama, Aichi 484-8506, Japan; Faculty of Nursing and Rehabilitation, Chubu Gakuin University, Kirigaoka 2-1, Seki, Gifu 501-3993, Japan.
authors.forename: Akichika
authors.initials: A
authors.lastname: Mikami
authors.affiliation: Cognitive Neuroscience Section, Primate Research Institute, Kyoto University, Inuyama, Aichi 484-8506, Japan.
authors.forename: Katsuki
authors.initials: K
authors.lastname: Nakamura
authors.affiliation: Cognitive Neuroscience Section, Primate Research Institute, Kyoto University, Inuyama, Aichi 484-8506, Japan. Electronic address: miyachi.shigehiro.8e@kyoto-u.ac.jp.
authors.forename: Shigehiro
authors.initials: S
authors.lastname: Miyachi
mesh_terms: D000200:Action Potentials / Q000502:physiology; D000818:Animals; D001522:Behavior, Animal / Q000502:physiology; D002755:Choice Behavior / Q000502:physiology*; D004193:Discrimination Learning / Q000502:physiology; D004569:Electroencephalography; D056344:Executive Function / Q000502:physiology*; D008253:Macaca mulatta; D008297:Male; D009474:Neurons / Q000502:physiology*; D017397:Prefrontal Cortex / Q000502:physiology*; D011597:Psychomotor Performance / Q000502:physiology*; D011930:Reaction Time / Q000502:physiology; D012438:Saccades / Q000502:physiology
keywords: Configural discrimination; Long-term memory; Medial prefrontal cortex; Nonhuman primate; Nonlinear association; Single neuronal activity