RIKEN Center for Brain Science Laboratory for Systems Neurophysiology

Team Director: Shigeyoshi Fujisawa (Ph.D.)

Japanese Page

Research Summary

Our main research goal is to elucidate the mechanisms of cognitive functions such as episodic memory and spatiotemporal recognition at the neural circuit level. To achieve this goal, we conduct studies using large-scale extracellular recordings from the hippocampus and cortex of behaving animals, such as rats, using silicon probes to simultaneously observe the activity of numerous neurons. Furthermore, by analyzing these data and constructing mathematical models, we aim to uncover how neurons contribute to cognitive functions and perform local circuit computations.

Main Research Fields

Complex Systems

Related Research Fields

Biological Sciences
Neuroscience-general-related
Cognitive and brain science-related
Basic brain sciences-related

Keywords

Neurophysiology
Hippocampus
Episodic memory
Spatial recognition

Selected Publications

1.Ouchi A & Fujisawa S.
"Predictive grid coding in the medial entorhinal cortex"
Science, 385:776-784. (2024)
2.Glykos V & Fujisawa S.
"Memory-specific encoding activities of the ventral tegmental area dopamine and GABA neurons"
Elife, 12:RP89743. (2024)
3.Kawahara D & Fujisawa S.
"Advantages of persistent cohomology in estimating animal location from grid cell population aactivity"
Neural Computation, 36:385-411. (2024)
4.Shimbo A, Izawa EI, & Fujisawa S.:
"Scalable representation of time in the hippocampus"
Science Advances, 7:eabd7013. (2021)
5.Norimoto H, Makino K, Gao M, Shikano Y, Okamoto K, Ishikawa T, Sasaki T, Hioki H, Fujisawa S, & Ikegaya Y.:
"Hippocampal ripples down-regulate synapses."
Science, 359:524-1527. (2018)
6.Danjo T, Toyoizumi T, & Fujisawa S.:
"Spatial representations of self and other in the hippocampus"
Science, 359:213-218. (2018)
7.Terada S, Sakurai Y, Nakahara H, & Fujisawa S.:
"Temporal and rate coding for discrete event sequences in the hippocampus"
Neuron, 94:1248-62. (2017)