动物实验 z-bio 2021-08-04 702

　　According to new research, when our brain wants to believe something beyond a certain limit, it will have hallucinations. This may happen to everyone occasionally, but in extreme cases, hallucinations are a symptom of a serious mental illness.

　　To find out the cause of our brain dysfunction, neuroscientist Katharina Schmack and colleagues at Cold Spring Harbor Laboratory induced hallucinations in mice. This is a difficult task. After all, you cannot interview rodents later.

　　"Mankind is now facing more and more failures in the face of serious mental illness. In the past few decades, the prognosis of patients with mental illness has not really been understood because of the neurobiological mechanisms of mental illness. There has been no substantial improvement." University of Washington Neurologist Adam Kepettis explained.

　　"Animal models can promote the progress of biomedicine in various other fields, but treatments cannot be advanced until animal models of mental illness are established."

　　Animal model is very necessary. But it also needs to be treated with caution. Similar to physiological studies that rely on animal models, we have seen their limitations, their development, how their environmental conditions are different from ours, and the similarities between them. You need to fully understand.

　　Researchers collect information by directly comparing test subjects’ responses to laboratory animals.

　　Human volunteers and mice need to capture certain tones in the background of noise. After hearing this news, a person clicked the confirmation button twice, and the trained mouse would respond to the tone. If you hear it, pierce your head into the red port, otherwise pierce your head into the blue port.

　　Among 220 volunteers, those who claimed to have experienced hallucinations were more likely to confidently capture tones without hallucination events. when

　　When mice were given ketamine (a known hallucinogen), they were more likely to stretch their heads toward the red edge without the tone.

　　Researchers can also increase the frequency of certain sounds. This raises the expectations of the mouse and enables it to "hear the hallucinations" more confidently. This situation also happens to humans. Through monitoring

　　In the brains of mice, the researchers detected elevated levels of dopamine before hallucinations-this chemical is known to be related to human hallucinations. The team then demonstrated that increasing dopamine levels causes mice to experience hallucination-like events more frequently, and antipsychotics that block dopamine can be used to reduce hallucinations.

　　“The brain seems to have a neural circuit to balance previous beliefs and evidence. The higher the baseline level of dopamine, the more it depends on previous beliefs,” Kepetch explained. "I believe that when this neural circuit is out of balance, hallucinations occur, and antipsychotics can rebalance."

　　7/Our results indicate that striatal dopamine is biased towards perception. This indicates that it may be affected. Cause hallucinations. I think the use of circuit mechanisms to support the long-standing psychosis dopamine hypothesis is cool.

　　Of course, Schmack and his colleagues still don't believe that the same thing happens to mice and humans. However, the system they are developing is expected to allow researchers to further study these issues to find new ways to treat mental illness.