Fruit Flies - Learning and Forgetting

Scripps Research scientists discovered a physiological mechanism in the brain through which a memory is formed and then forgotten. To discover this, scientists conducted the study on fruit flies where they conditioned the flies to associate a particular odour with an electric shock. Once this has been set up, scientists observe that they subsequently avoid that odour, which confirms that the memory has been formed.

After monitoring the activity of neurons in the brain while conditioning procedure, they got an inside look at the physiological underpinnings of memory arrangement.  Jacob Berry, Ph.D., from Department of Neuroscience on Scripps Research’s Florida campus said, “We believe this system is set up to remove memories that are unimportant and not necessarily supposed to last a long time. I find it elegant that all of this is done with the same neuron. Our paper highlights exactly how this is achieved.” In earlier work, the Scripps Research team showed that there are specific dopaminergic circuits involved in both the formation of memory and the removal of memories. In the current study, the investigators used imaging techniques to look at the process in detail. The scientists had discovered that when a behavioural memory is degraded, the cellular changes made during the learning process are reversed by the same dopamine neuron that helped form the changes in the first place. In earlier work, the Scripps Research team showed that there are specific dopaminergic circuits that are involved in both the formation of memory and the removal of memories. In the current study, the investigators used imaging techniques to look at the process in more detail. Scientists also found that when dopamine neuron is recruited to form a new memory, it also works to degrade older memories. Berry also said that this learning and forgetting process helps to explain retroactive interference, a common observation in psychology. Retroactive interference describes the situation when more recent information gets in the way of trying to recall older information. However the research was conducted on fruit flies, the investigators expect that the findings to apply to higher organisms, including humans. According to him evolution worked out a lot of important processes like this pretty early on because of which there's a lot of relevance to studying these synaptic pathways in simpler organisms. Berry’s research and study not only provides new insights into the brain mechanisms for active forgetting but offers a wonderful example of how much can be known about brain function from laboratory animals like the fruit fly. The process of understanding both remembering and forgetting memory has a number of implications for humans like for conditions like drug addiction or post-traumatic stress disorder, it may be beneficial to develop approaches that can boost active forgetting whereas Improving memory retention helps to treat dementia and other forms of memory loss.

By- Anuja Arora

Content: https://www.sciencedaily.com/releases/2018/11/181127092528.htm