Researchers have been able to alter the memories of mice, making them lose their fear of a place where they were shocked, and making them fear a place where they had recently had a pleasurable experience with a female, NBC News
The experiment shows there is a clear physical pathway in the brain that connects memories with the emotional weight given to them – that it can be disrupted, the researchers report in the journal Nature.
“We have no intention … to use this kind of technology in order to alter normal, healthy people’s minds,” said lead researcher Susumu Tonegawa of the Picower Institute at the Massachusetts Institute of Technology.
But the study does show what’s possible and it demonstrates a fairly simple mechanism that the brain uses to help animals — including people — classify memories.
“Hopefully, we can inspire other labs and other groups of people to imagine translating this information into a way that can be applied in humans,” added Roger Redondo, one of the neuroscientists who worked on the study.
Last year, the MIT team reported implanting false memories in mice. They used a similar technique to genetically manipulate the connections in the brain that link the hippocampus — the seat of memories — to the amygdala, where emotions such as fear and pleasure originate, so that the brain cells would respond to a pulse of blue laser light.
“When blue light is sensed by the molecule, the molecule changes shape,” Redondo said. This allows neurotransmitters to enter the neuron and turn it “on” or “off.”