Studies show that erasing memories is possible and brain can be rewired. The premise of the movie, 'Eternal Sunshine of the Spotless Mind' might be true after all.
"Recalling a memory is not like playing a tape recorder," said Susumu Tonegawa of the Massachusetts Institute of Technology. "It's a creative process."
In the study published in Nature, scientists researched on "memory reconsolidation," which is a process where in "when a memory is retrieved, its physical manifestation in the brain is so 'labile' or changeable, that it can be altered." Scientists have found out that "false memories can form, and emotions associated with memories can be altered."
According to Reuters, even though the tests were done on lab rodents, there is imminent evidence that the "malleability of memory might be exploited to treat disorders such as post-traumatic stress," and pave way for erasing memories.
The researchers from MIT experimented by giving male mice a small electric shock when the animals walked over to a portion of their cage, thus creating a memory which linked that place to a feeling of pain; while on a different area of the cage, the male mice mingled with the female mice, giving out a feeling of pleasure.
Through the use of a technique called "optogenetics," the brain neurons of the mice were engineered to light up.
The scientists "rewired" the brains of the mice by changing patterns of pleasure and pain.
"We could switch the mouse's memory from positive emotions to negative, and negative to positive," said Tonegawa.
However, the researchers recommended a more intensive research before they apply this study on humans; although the human brain circuits were found to be very similar to that of mice.
Meanwhile, in a different study published on PLOS One, scientists also took advantage of the "malleability of reactivated memories to erase them completely," meaning, experts are tapping on the possibility of erasing memories on living things.
The scientists have trained rats that a flash of light comes before a shock to reactivate a memory. Scientists reported that they have given the animals xenon gas immediately. Xenon gas is an anesthetic that blocks molecules in memory formation.
According to psychologist Edward Meloni of Harvard Medical School, this process affected the memory reconsolidation of the rats. "The rats forgot that light precedes a shock. Similarly trained rats not given xenon remembered just fine," the report said.
However, Elizabeth Phelps, a psychologist from New York University said that although these results have shown "interesting advances," there were still clear ethical issues that scientists have to deal with in the matter of erasing memories or rewiring brains, manipulating human memories, even if the process is used for "therapeutic purposes."
"I think we are still a long way from translating this research to good clinical interventions," said Phelps, stating that "memories that contribute to post-traumatic stress disorder are 'likely much more complex' [in humans] than in mice and rats.
