Novelty-induced phase-locked firing to slow gamma oscillations in the hippocampus : requirement of synaptic plasticity

• Main Authors: Kitanishi, Takuma, Ujita, Sakiko, Fallahnezhad, Mehdi, Kitanishi, Naomi, Ikegaya, Yuji, Tashiro, Ayumu
• Other Authors: School of Biological Sciences
• Format: Article
• Language: English
• Published: 2015
• Subjects: DRNTU::Science::Biological sciences::Human anatomy and physiology::Neurobiology
• Online Access: https://hdl.handle.net/10356/79371; http://hdl.handle.net/10220/38371
• Institution: Nanyang Technological University

Temporally precise neuronal firing phase-locked to gamma oscillations is thought to mediate the dynamic interaction of neuronal populations, which is essential for information processing underlying higher-order functions such as learning and memory. However, the cellular mechanisms determining phase locking remain unclear. By devising a virus-mediated approach to perform multi-tetrode recording from genetically manipulated neurons, we demonstrated that synaptic plasticity dependent on the GluR1 subunit of AMPA (α-amino-3-hydroxy-5-methyl-4-isoxazole propionate) receptor mediates two dynamic changes in neuronal firing in the hippocampal CA1 area during novel experiences: the establishment of phase-locked firing to slow gamma oscillations and the rapid formation of the spatial firing pattern of place cells. The results suggest a series of events potentially underlying the acquisition of new spatial information: slow gamma oscillations, originating from the CA3 area, induce the two GluR1-dependent changes of CA1 neuronal firing, which in turn determine information flow in the hippocampal-entorhinal system.