Professor Kaoru Inoguchi and his colleagues at the Department of Biochemistry, Graduate School of Medicine, University of Toyama announced on January 1 that they have elucidated the mechanism of the nerve cell population (memory trace cell population) that associates memory.
Humans form knowledge and concepts by associating various memory information stored in the brain.Memories are stored in the brain by specific nerve cell populations, and when memories are related to each other, it has been reported that the cell populations that control each memory overlap, but the role of the overlapping cell populations was unknown. ..
Using mice, the research group established a higher-order associative experimental system that links two associative memories: taste aversion learning (CTA) and sound fear conditioning (AFC).When each conditioned stimulus (saccharin aqueous solution for CTA, buzzer sound for AFC) was reminded at the same time, the originally separately obtained CTA memory and AFC memory were associated.
That is, when a saccharin aqueous solution was drunk, a freezing reaction was exhibited as when a buzzer sound was heard.At that time, in the amygdala, which controls CTA memory and AFC memory, the overlap of memory trace cell populations corresponding to each memory increased.Conversely, experimental suppression of only the activity of overlapping engram cell populations when recalling memory reduced the rate of association between the two associated memories.
On the other hand, the memories of CTA and AFC, that is, the memories of the original, remained normal.This revealed that the overlapping engram cell populations were involved only in the memory association and were not necessary for the recall of each memory.
This research is an achievement that leads to the elucidation of human higher brain functions such as the formation of knowledge and concepts.In addition, unnecessary links between weakly related memories are closely related to PTSD (post-traumatic stress disorder) and other psychiatric disorders, so this result is a treatment for these disorders. It is expected to lead to creation.
