title: Observational learning in mice can be prevented by medial prefrontal cortex stimulation and enhanced by nucleus accumbens stimulation.
abstract: The neural structures involved in ongoing appetitive and/or observational learning behaviors remain largely unknown. Operant conditioning and observational learning were evoked and recorded in a modified Skinner box provided with an on-line video recording system. Mice improved their acquisition of a simple operant conditioning task by observational learning. Electrical stimulation of the observer's medial prefrontal cortex (mPFC) at a key moment of the demonstration (when the demonstrator presses a lever in order to obtain a reward) cancels out the benefits of observation. In contrast, electrical stimulation of the observer's nucleus accumbens (NAc) enhances observational learning. Ongoing cognitive processes in the demonstrator could also be driven by electrical stimulation of these two structures, preventing the proper execution of the ongoing instrumental task (mPFC) or stopping pellet intake (NAc). Long-term potentiation (LTP) evoked in these two cortical structures did not prevent the acquisition or retrieval process--namely, mPFC and/or NAc stimulation only prevented, or modified, the ongoing behavioral process. The dorsal hippocampus was not involved in either of these two behavioral processes. Thus, both ongoing observational learning and performance of an instrumental task require the active contribution of the mPFC and/or the NAc.
authors.affiliation: Division of Neurosciences, Pablo de Olavide University, 41013-Seville, Spain.
authors.forename: M Teresa
authors.initials: MT
authors.lastname: Jurado-Parras
authors.forename: Agnès
authors.initials: A
authors.lastname: Gruart
authors.forename: José M
authors.initials: JM
authors.lastname: Delgado-García
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000502:physiology*; D003216:Conditioning, Operant / Q000502:physiology*; D004558:Electric Stimulation; D004567:Electrodes, Implanted; D006624:Hippocampus / Q000502:physiology*; D007100:Imitative Behavior / Q000502:physiology; D007858:Learning / Q000502:physiology*; D017774:Long-Term Potentiation / Q000502:physiology; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D009434:Neural Pathways / Q000502:physiology; D009714:Nucleus Accumbens / Q000502:physiology*; D017397:Prefrontal Cortex / Q000502:physiology*; D012201:Reward