MIT scientists successfully implant false memories in mice

Alec Hill Contributor
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“Memories can be unreliable.”

No, that quote doesn’t come from the opening lines of a science fiction novel, nor from the narration of the movie “Inception.”

Instead, the words are from the abstract of a new study  published in the latest edition of the academic journal Science, in which scientists at the Massachusetts Institute of Technology caused mice to feel mild pain, and then successfully triggered memories of that pain in environments where the mice had no reason to expect it.

The eight authors of the study summarize their results in dense technical language, but the import of their experiments is clear: manipulations of the mind that were once the terrain of futuristic fantasy are now one step closer to becoming reality.

“It is possible to generate an internally-represented and behaviorally-expressed fear memory via artificial means,” the report reads. One of the study’s editors adds that the authors “were able to generate a false memory and study its neural and behavioral interactions with true memories.”

Roughly, their experiments worked as follows: scientists conditioned mice to fear an environment, Room One, by delivering simultaneous shocks to the mice’s feet and flashes of blue light inside their skulls via fiber optic cable as a way of triggering neurons to create a memory of the pain.

The mice were next introduced to a different environment, Room Two, and the team found that when the blue light was used again, the mice reacted with fear, associating it with a pain that was not imminent.

“Big deal,” one might scoff. “Of course they were scared they would be shocked again when the blue light was used as a trigger. I would be, too.” All of the above, however, was published over a year ago by the team at MIT in the journal Nature, and is only a prelude to their more recent experiment.

In the earlier experiment, the scientists noted that the memories were only triggered in “context specific” situations and that questions remained: “It is unclear whether it is possible to elicit the behavioural output of a specific memory by directly activating a population of neurons that was active during learning,” the first report notes, setting up their next experiment.

More recently, the scientists introduced mice to a room, then placed them in a second environment, and then triggered the blue light and the shock. Upon placing the mice back into the original chamber, which the mice should have associated with safety after having not been shocked there originally, the mice still reacted with fear when the blue light was triggered.

In essence, the experiments caused the mice to remember pain in an environment they had been trained to trust.

The science world reacted to the news with enthusiasm. Psychologist Elizabeth Loftus told Fox News that the results were “very exciting.”

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