先天的と後天的な嗅覚情報の統合を支える脳内情報処理とメカニズム

2023 Fiscal Year Research-status Report

• Project/Area Number: 23KF0090
• Research Institution: Institute of Physical and Chemical Research
• Principal Investigator: 風間 北斗 国立研究開発法人理化学研究所, 脳神経科学研究センター, チームリーダー (90546574)
• Co-Investigator(Kenkyū-buntansha): CHERNG BOR-WEI 国立研究開発法人理化学研究所, 脳神経科学研究センター, 外国人特別研究員
• Project Period (FY): 2023-04-25 – 2025-03-31
• Keywords: olfactory processing / Drosophila / innate behavior / learned behavior

Outline of Annual Research Achievements

We developed an olfactory conditioning paradigm, which can be conducted under a two-photon microscope for simultaneous tracking of neural activity and behavior throughout learning. To monitor neural activity in behaving animals over the entire stages of learning, we devised a closed-loop system responding to the real-time state of a behaving fly, which is compatible with neural recording from multiple brain regions at single-cell resolution with two-photon calcium imaging. To alter the innate value of odors through training, we employed an olfactory conditioning paradigm, associating the value of reinforcers such as reward (e.g., sweet taste) or punishment (e.g., bitter taste) with odors. We also used optogenetic stimulation of gustatory receptor neurons as a reinforcer.

Current Status of Research Progress

2: Research has progressed on the whole more than it was originally planned.

Reason

We were able to develop an olfactory conditioning paradigm compatible with simultaneous tracking of behavior and neural activity as planned. A setup to monitor the behavior and to deliver reinforcers (both real and optogenetically applied) is also successfully built.

Strategy for Future Research Activity

In the second year, we aim to test the hypothesis that the conditioning changes olfactory representations in the LH, or in the upstream/downstream regions. First, given the presence of an anatomical input from the MB to the LH, we will test if olfactory representations in the LH are updated. Second, we will test if changes in olfactory representations take place in regions downstream of both the MB and the LH. Finally, we will test if learning can also modulate the earlier olfactory center. We will further examine the circuit mechanism underlying neural plasticity following conditioning. We will test whether learning-dependent changes in olfactory representations in the LH and downstream regions are induced by mechanisms intrinsic to each region or through interactions between the MB.

Causes of Carryover

The budget was executed almost as planned. We make the best use of the small remainig amount to accelerate the research next fiscal year.