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Kaneko, J.

Publications and source records attributed to Kaneko, J..

2 recordsLinked to original sources

Memory schema reorganization induced by the deliberate processing in the executive network supported by widespread amplified activity

Schema accommodation is the reorganization of a preexisting memory schema to deeply accept new information incongruent with it. Although it is crucial for flexible intelligence, it occurs infrequently, making its neural basis difficult to study. To overcome this, we conducted an fMRI experiment using a newly developed experimental paradigm, the reversal description task. The results suggest that the schema changes that occurred during the task were global reorganizations rather than local adjustments. Moreover, the executive network responsible for deliberate processing played a central role, with the support of widespread amplified activity. Furthermore, reinforcement learning-based control implemented in these neural substrates, in cooperation with the caudate nucleus, emerged as a candidate mechanism for the deliberative schema update. These findings indicate that memory reorganization involves not only automatic but also deliberate processes, in which the desired global structure is explored through the control operation performed by these neural bases. TeaserMemory reorganization is performed through deliberation-related neural computations supported by brain-wide amplified activity.

neuroscience↗

Dentate neurogenesis mediates cognitive flexibility via modulation of the hippocampal longitudinal-axis network

Adult neurogenesis endows the hippocampus with unparalleled neural plasticity, essential for intricate cognitive functions. However, the manner in which sparse newborn neurons (NBNs) modulate neural activities and subsequently shape behavior remains enigmatic. Utilizing a newly engineered NBN-Tetanus Toxin mouse model, we non-invasively silenced NBNs and confirmed their crucial role in cognitive flexibility, as demonstrated through reversal learning in the Morris water maze and the Go/Nogo task in operant learning. Pairing task-based functional MRI (tb-fMRI) with operant learning revealed a dorsal hippocampal hyperactivation during Nogo task, implying that hippocampal hyperexcitability might underlie the observed behavioral deficits. Notably, resting-state fMRI (rs-fMRI) revealed enhanced functional connectivity between the dorsal and ventral dentate gyrus following NBN silencing. Further exploration of PV+ interneurons and mossy cells activities highlighted NBNs integral part in preserving the excitation/inhibition balance within the hippocampus. Our findings emphasize how the neural plasticity driven by NBNs extensively modulates the hippocampus, sculpting cognitive flexibility.

neuroscience↗