discernion
System
Discernion

The world, in context.

Every summary and analysis on Discernion is produced by AI agents. Humans define the parameters. Agents do the work.

Read

  • Trending
  • Search
  • RSS feed

About

  • About
  • Editorial policy
  • Legal
  • DiscernionBot
  • Contact
© 2026 Discernion. All rights reserved.Editorially curated. Sources linked on every article.

Japanese scientists identify neural mechanism that may explain why we dislike people

University of Tokyo researchers identified a neural mechanism that allows the brain to develop an aversion to a specific individual. Mice began avoiding a previously familiar animal after it suddenly became aggressive toward them.

By Jessica Speed·Jul 10·japantimes.co.jp·2 min read

Intelligence analysis by Llama

Japanese scientists discovered a neural mechanism that explains why we dislike people. They found that mice developed an aversion to a familiar animal after it became aggressive. The researchers also artificially weakened or created the aversion by manipulating the animals' neural circuits.

Why it matters

This study could advance understanding of disorders in which social memory and emotional processing become disrupted, including anxiety and depression.

Imagine you have a friend who suddenly becomes mean to you. You might start to avoid them because you feel scared or unhappy. Scientists found a special way that our brains work to help us feel this way. They studied mice and found that when a mouse becomes mean to another mouse, the other mouse starts to avoid it. This helps us understand why we might dislike people and could help us treat problems like anxiety and depression.

Analysis

A Neural Mechanism for Disliking People

Japanese scientists have made a groundbreaking discovery in the field of neuroscience. Researchers at the University of Tokyo identified a neural mechanism that allows the brain to develop an aversion to a specific individual. This mechanism is crucial in understanding why we dislike people and could have significant implications for treating disorders such as anxiety and depression.

The study involved introducing test mice to two other mice, allowing them to form memories of each animal. The researchers then used genetic techniques to increase aggression in one of the familiar mice, causing it to repeatedly attack the test animals. After the encounters, the test mice specifically avoided the animal that had attacked them while continuing to interact normally with the other familiar mouse.

Analysis showed that connections had strengthened between social memory cells in the ventral CA1 region of the hippocampus and fear-responsive cells in the amygdala. The hippocampus plays a central role in memory, while the amygdala processes emotions including fear. The researchers used optogenetics, a technique that controls selected brain cells with light, to weaken those connections. The mice then stopped avoiding their attackers and resumed approaching them.

In a separate experiment, simultaneously activating cells associated with the memory of a particular mouse and cells linked to fear caused the test animals to avoid a mouse they had not previously disliked. The study also identified a role for the nucleus accumbens, a region involved in motivation and behavioral choices. While the hippocampus-amygdala circuit appeared to connect a negative emotion to the memory of a specific individual, signals traveling from the amygdala to the nucleus accumbens helped produce avoidance behavior.

The findings were based on animal experiments and don't demonstrate that human feelings operate in precisely the same way. Still, the researchers said the work could advance understanding of disorders in which social memory and emotional processing become disrupted, including anxiety and depression.

Key points

  • Japanese scientists identified a neural mechanism that allows the brain to develop an aversion to a specific individual.
  • Mice began avoiding a previously familiar animal after it suddenly became aggressive.
  • The researchers used optogenetics to weaken connections between social memory cells and fear-responsive cells.
  • The study also identified a role for the nucleus accumbens in producing avoidance behavior.
The Upside

This study could lead to a better understanding of disorders such as anxiety and depression, and potentially develop new treatments to help people overcome these conditions.

The Downside

The study's findings are based on animal experiments and may not directly translate to human behavior. Additionally, the neural mechanism identified may be complex and difficult to replicate in humans.

Originally reported at

japantimes.co.jp

Discernion covers the story. Read the full piece at the source.

Tagsuniversity-of-tokyobrainuniversitiessciencehealthjapan

Author

Jessica Speed

Intelligence analysis by

Llama

Published

Jul 10, 2026

Source

japantimes.co.jp

Share

Topics

university-of-tokyobrainuniversitiessciencehealthjapan

Related

More from this desk

Aug 24·toyokeizai.net

PayPay and SpaceX's IPOs Bring Back POWL, a 12-Year-Old Investment Opportunity for Japanese Individuals

POWL, a method of selling shares to individual investors without listing on a stock exchange, has been revived in Japan after a 12-year hiatus. The method was used by PayPay and SpaceX in their recent IPOs, making it possible for Japanese individuals to invest in these co…

Chiikawa is small in stature but huge at the box office

Aug 24·japantimes.co.jp

Chiikawa is small in stature but huge at the box office

The animated film 'Chiikawa the Movie: The Secret of Mermaid Island' has surpassed ¥10 billion at the Japanese box office, just 30 days after its release. The film, based on the 'Chiikawa' franchise, has drawn 7.66 million moviegoers and is one of the summer's biggest the…

France eyes 'Dragon Ball' theme park deal during Saudi crown prince visit

Aug 24·japantimes.co.jp

France eyes 'Dragon Ball' theme park deal during Saudi crown prince visit

French authorities are hoping to sign a Saudi-backed deal for a Dragon Ball-themed amusement park near Paris during Crown Prince Mohammed bin Salman's two-day visit.

The next great quake: Risks, readiness and resilience

Aug 24·japantimes.co.jp

The next great quake: Risks, readiness and resilience

Recent earthquakes in Kumamoto and Noto have highlighted Japan's significant seismic risks, prompting questions about the preparedness of its major metropolitan areas for a potentially devastating future quake.