Nat Neurosci Li Bo's team discovers a new loop mechanism of punishment and reward behavior in the amygdala

Editor-in-Chief | The amygdala is the subcortical center of the limbic system of the brain.
It is a highly conserved brain area in evolution.
It is mainly responsible for processing emotions, motivations, etc.
and various behaviors related to it
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Abnormal function of the amygdala is closely related to many psychological and psychiatric diseases, including stress response, anxiety, depression and so on
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The amygdala includes the basolateral nucleus and the central nucleus in structure.
The basolateral nucleus is a research hotspot in the field of neurobiology in recent years because it is similar to the cerebral cortex in cell type and development
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How the neurons in the basolateral amygdala encode punishment and reward stimuli and how to regulate punishment and reward-related learning and memory have attracted the attention of many neuroscientists in the past ten years
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Dr.
Zhang Xian of the Li Bo research group of Cold Spring Harbor Laboratory published a paper in Nature Communications in 2018 by using calcium ion signal imaging to detect the activity of neurons in this brain area in real time, and found that the basolateral nucleus after conditional learning The neurons in the population show the phenomenon of inhibited neural activity
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This discovery changed the traditional theory that neuronal responses would increase after conditional learning
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The author further found through population coding analysis that the noise correlation of neurons after conditional learning was significantly reduced, indicating that the population neurons of the basolateral nucleus after conditional learning can increase the signal-to-noise ratio by inhibiting the activities of many unrelated neurons, thereby allowing Directly related neurons can encode information more accurately
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So how can we find these neurons that directly encode emotions and observe the behavior of animals by activating/inhibiting these neurons? On October 18, 2021, Li Bo's research group at Cold Spring Harbor Laboratory in the United States (Dr.
Zhang Xian is the first and co-corresponding author of the article) published a new work on brain regulation of emotional memory and learning behavior in Nature Neuroscience Online Genetically identified amygdala -Striatal circuits for valence-specific behaviors, clarified the important role of the two neural circuits from the amygdala to the ventral striatum in regulating punishment and reward behaviors and related learning
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In cooperation with Professor Z.
Josh Huang (), a well-known neurobiologist from Cold Spring Harbor Laboratory, Dr.
Zhang Xian under the guidance of Professor Li Bo conducted a systematic study on neurons expressing the Fezf2 gene in the basolateral amygdala, including In vivo single-photon calcium signal imaging, optogenetics, chemical genetics, physiological response detection, and various behavioral methods have discovered neurons and their downstream neural circuits that encode rewards and punishments respectively
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The Fezf2 gene is a highly conserved gene segment, and the transcription factors it encodes are essential for the development of excitatory neurons
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The author first used in vivo single-photon calcium signal imaging technology to perform real-time imaging of neurons expressing the Fezf2 gene in the basolateral amygdala, and found that these neurons were divided into two categories: one encoding reward stimuli, and the other encoding punishment stimuli
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Next, after conditioned learning and training on experimental mice, it was found that more neurons were involved in the coding of conditioned stimuli
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The author then traced the upstream and downstream neural circuits of these two types of neurons and found that different upstream and downstream brain regions are involved in the encoding of different emotional information
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The most noteworthy are the two neural pathways from the basolateral amygdala (BLA) to the ventral striatum: basolateral amygdala-nucleus accumbens (BLA-NAc), basolateral amygdala-olfactory nodules ( BLA-OT)
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The nucleus accumbens and the olfactory tubercle, as the two subregions of the ventral striatum, have traditionally been regarded as a relay station for emotional reactions and behavioral activities
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The function of the neural pathway of BLA-NAc has been controversial in previous literature reports, and the function of the BLA-OT loop has never been reported
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The experimental results of optogenetics showed that activating the BLA-NAc and BLA-OT pathways caused animals to show behaviors of evading punishment and pursuing rewards respectively, and at the same time, they were accompanied by obvious pupil dilation
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This combination of behavior and physiological response implies that these two pathways should also play an important role in emotional learning
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In order to test this hypothesis, the author used optogenetics and chemical genetics methods to inhibit the neural activity of these two pathways, and found that the inhibition interfered with punishment learning and reward learning, respectively
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This study provides new insights into the functions of the basolateral amygdala and its downstream neural circuits, and provides important data support for revealing the regulation mechanism of specific types of neurons in the basolateral amygdala on emotional responses.
Related mental illnesses caused by nuclear damage and degeneration provide new clues
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Neurons in the basolateral amygdala that encode punishment (red) and reward (green)
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These two types of neurons project to the nucleus accumbens and the olfactory tubercle respectively
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Original link: https://doi.
org/10.
1038/s41593-021-00927-0 Platemaker: Notes for reprinting on the 11th [Non-original article] The copyright of this article belongs to the author of the article.
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