The process of uncoupling the overlapping memories in several varieties of mice has been successfully done by a group of scientists hailing from the University of Toyama located in Japan. Two of the Japanese researchers from this team explained in the paper published in a journal named Science that they initially induced a couple of separate memories successfully in the mice on which they tested, they caused overlapping of the two memories after which later they uncoupled those two memories without deleting any of them.
It is well-known in the world of science that among the various types of memories which are present some can even overlap.
Like for example if one avoids any kind of sweetener and also discovered that it hurts very much when your hand gets caught in a door, one can easily observe that these memories overlap if they occur simultaneously together. This can cause any person to wince in pain if they consume any drink which has the undesired sweetener in it. In the new experiment conducted by the Japanese scientists, the researchers were able simulate an experiment where they were successful in causing an overlapped memory not to overlap in mice without changing or affecting the memory.
The experiment was conducted in manner in which the mice were forced to have a bad memory of consuming and tasting of saccharine several times and whenever they did so, the mice received a dose of lithium chloride that caused them to be sick. Few days later, whenever a certain tone was being played the same mice received an electric shock, introducing another bad memory. Then the researchers combined the two memories. This time the mice were allowed to like food containing saccharine awhile the tone was being played at the same time. These actions caused overlapping of the two memories.
After the incident whenever the mice tasted saccharin they froze in expectation of a shock. While continuing the experiment the researchers were able to identify the neurons responsible in the mice for keeping a hold of the two memories, and also the neurons which caused the overlap of the two memories which the mice were holding. After training all the mice properly for a few days the scientists tried to observe that whether all the mice had incorporated those overlapping memories in a proper manner. After they were satisfied the scientists used the various methods of optogenetics that they could switch between the on and off condition of the overlapping cells.
When they were turned off their mice did froze while tasting saccharin suggesting that the overlapping memory was turned off. In spite of all this the mice were still able to remember the unpleasant taste which was associated with saccharin while tasting it and also froze in fear of the electric shock whenever the tone was played. Whenever the overlapping neurons were turned on back again, then all the overlapping memories returned again.
The scientists claim that this experiment provided a great deal of new insight into the working of memory in mammals. The experiment also suggested that these actions might help in removing certain overlapping memories which caused various diseases such as post-traumatic stress disorder (PTSD).