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Tanisumi, Y.

Publications and source records attributed to Tanisumi, Y..

5 recordsLinked to original sources

Behavioral expression of decision confidence engages disentangled confidence coding in the orbitofrontal cortex

Task engagement is thought to recruit subsets of neurons encoding task-relevant variables, but it remains unclear whether it also reorganizes the geometry of population codes and how such reorganization supports behavior. Here we show that, in the orbitofrontal cortex (OFC), task engagement aligns population activity along a confidence axis, thereby enabling the behavioral use of decision confidence. We recorded OFC activity while rats performed two variants of the same perceptual decision-making task that differed only in reward-timing uncertainty, which altered the utility of post-decision confidence for guiding reward waiting. OFC neurons exhibited more linear responses to confidence when confidence was more strongly expressed in behavior. Although the proportion of OFC neurons encoding confidence was similar across strategies, strategy-dependent alignment of population activity to confidence emerged under variable long delays, and this alignment predicted confidence-based waiting behavior. These findings suggest that OFC population codes flexibly adapt to the behavioral relevance of task variables, linking cognitive strategy to the geometry of neural representation.

neuroscience↗

An intra-oral flavor discrimination task in freely moving mice

Flavor plays a critical role in the pleasure of food. Flavor research has mainly focused on human subjects and revealed that many brain regions are involved in flavor perception. However, animal models for elucidating the mechanisms of neural circuits are lacking. Herein, we demonstrate the use of a novel behavioral task in which mice are capable of flavor discrimination. When the olfactory pathways of the mice were blocked, they could not perform the task. However, behavioral accuracy was not affected when the gustatory pathway was blocked by benzocaine. These results indicate that the mice performed this discrimination task mainly based on the intraoral flavor. We conclude that this novel task can contribute to research on the neural mechanisms of flavor perception.

neuroscience↗

Encoding of odor information and reward anticipation in anterior cortical amygdaloid nucleus

Olfactory information directly reaches the amygdala through the olfactory cortex, without the involvement of thalamic areas, unlike other sensory systems. The anterior cortical amygdaloid nucleus (ACo) is one of the olfactory cortices that receives olfactory sensory input, and is part of the olfactory cortical amygdala, which relays olfactory information to the amygdala. To examine its electrophysiological features, we recorded individual ACo neurons during the odor-guided go/no-go task to obtain a water reward. Many ACo neurons exhibited odor-evoked go cue-preferred during the late phase of odor-sampling supporting the population dynamics that differentiate go/no-go responses before executing the odor-evoked behaviors. We observed two types of neurons with different anticipation signals: one neuron type exhibited gradual increases of activity toward reward delivery, while another type exhibited a phasic go cue-preferred activity during odor sampling as well as another phasic anticipatory activity for rewards. These results suggest that the ACo may be involved in reward-related behavioral learning by associating the olfactory information with reward anticipation.

neuroscience↗

Bi-directional encoding of context-based odor signals and behavioral states by the nucleus of the lateral olfactory tract neurons

The nucleus of the lateral olfactory tract (nLOT) is not only a part of the olfactory cortex that receives olfactory sensory inputs from the olfactory bulb, but also one of the cortical amygdala areas that regulates motivational behaviors. To examine how the neural ensemble activity of the nLOT is modulated by motivational processes that occur during various states of learned goal-directed behaviors, we recorded nLOT spike activities of mice performing odor-guided go/no-go tasks for obtaining a water reward. We found that the majority of the nLOT neurons exhibited sharp go-cue excitation and persistent no-go-cue inhibition responses triggered by an odor onset. The bi-directional cue encoding introduced nLOT population response dynamics and provided a high odor decoding accuracy before executing cue-odor-evoked behaviors. The go-cue preferred neurons were also activated in the reward drinking state, indicating context-based odor-outcome associations. These findings suggest that the nLOT neurons play an important role in the translation from context-based odor information to appropriate behavioral motivation.

neuroscience↗

Tuning of ventral tenia tecta neurons of the olfactory cortex to distinct scenes of feeding behavior

Ventral tenia tecta (vTT) is a part of the olfactory cortex that receives both olfactory sensory signals from the olfactory bulb and top-down signals from the prefrontal cortex. To address the question whether and how the neuronal activity of the vTT is modulated by prefrontal cognitive processes such as attention, expectation and working memory that occurs during goal-directed behaviors, we recorded individual neuronal responses in the vTT of freely moving awake mice that performed learned odor-guided feeding and drinking behaviors. We found that the firing pattern of individual vTT cells had repeatable behavioral correlates such that the environmental and behavioral scene the mouse encountered during the learned behavior was the major determinant of when individual vTT neurons fired maximally. Furthermore, spiking activity of these scene cells was modulated not only by the present scene but also by the future scene that the mouse predicted. We show that vTT receives afferent input from the olfactory bulb and top-down inputs from the medial prefrontal cortex and piriform cortex.\n\nThese results indicate that different groups of vTT cells are activated at different scenes and suggest that processing of olfactory sensory information is handled by different scene cells during distinct scenes of learned feeding and drinking behaviors. In other words, during the feeding and drinking behavior, vTT changes its working mode moment by moment in accord with the scene change by selectively biasing specific scene cells. The scene effect on olfactory sensory processing in the vTT has implications for the neuronal circuit mechanisms of top-down attention and scene-dependent encoding and recall of olfactory memory.

neuroscience↗