Successful Execution of Working Memory Linked to Synchronized High-Frequency Gamma Oscillations

• Published in: Cell Vol. 157; no. 4; pp. 845 - 857
• Main Authors: Yamamoto, Jun, Suh, Junghyup, Takeuchi, Daigo, Tonegawa, Susumu
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 08.05.2014
• Subjects: Animals; Electrophysiological Phenomena; Entorhinal Cortex - cytology; Entorhinal Cortex - physiology; Hippocampus - cytology; Hippocampus - physiology; Male; Maze Learning; Memory, Short-Term; Mice; Mice, Inbred C57BL; Mice, Transgenic; Neurons - physiology
• ISSN: 0092-8674; 1097-4172
• DOI: 10.1016/j.cell.2014.04.009

Neuronal oscillations have been hypothesized to play an important role in cognition and its ensuing behavior, but evidence that links a specific neuronal oscillation to a discrete cognitive event is largely lacking. We measured neuronal activity in the entorhinal-hippocampal circuit while mice performed a reward-based spatial working memory task. During the memory retention period, a transient burst of high gamma synchronization preceded an animal’s correct choice in both prospective planning and retrospective mistake correction, but not an animal’s incorrect choice. Optogenetic inhibition of the circuit targeted to the choice point area resulted in a coordinated reduction in both high gamma synchrony and correct execution of a working-memory-guided behavior. These findings suggest that transient high gamma synchrony contributes to the successful execution of spatial working memory. Furthermore, our data are consistent with an association between transient high gamma synchrony and explicit awareness of the working memory content. [Display omitted] •Synchronized high gamma incidents (sHGIs) precede correct working memory behavior•Synchronized high gamma incidents precede self-correction of incorrect behavior•sHGI and correct working memory behavior are coordinately inhibited by optogenetics•sHGIs may be associated with awareness of working memory content A strong temporal association between a particular neural oscillation, a transient burst of high gamma synchronization, and correct execution of a behavior guided by working memory in mice is observed and further probed by optogenetic intervention into the relevant circuit.