A new study in Science Advances by Professor Yun Zhang's lab shows that forgetting does not reverse the learning process, rather it generates a new status of the brain.
We all forget events we've experienced and knowledge we've learned in the past. Forgetting is part of normal brain functions due to the limited capacity of the brain. But, understanding forgetting is key to addressing mechanisms underlying many mental health issues. For example forgetting averse experiences may be associated with post-traumatic stress disorder. Mutants of several autism-risk genes in model animals displayed behavioral defects associated with impaired forgetting.Forgetting is intuitively related to our daily activities, but how does it take place in the brain?
Using the aversive olfactory learning of pathogenic bacteria in C. elegans the researchers showed that by examining whole-brain gene expression, both neural activity and behavior output, forgetting does not simply erase the memory nor reverse the learning process. Instead it generates a brain state that is different from the naive state and the learned state. The team also found molecules, which function in both invertebrate and vertebrate brains, that can tune the speed of forgetting. Harvard Gazette.