Mice given false memories in brain study

Scientists have made mice scared of a location where nothing bad ever happened to them. It may sound like an evil plan, but it could unlock secrets about how memories are formed and altered.

The project was the work of a team including Dr Xu Liu or the Center for Neural Circuit Genetics based at the Massachusetts Institute of Technology. It aimed to explore the way in which humans can have false memories.

The research worked on the way that memories, although seemingly intangible, are effectively data stored by a combination of neurons. The researchers believe that every time we retrieve a memory, it’s possible the act of retrieval changes the combination of neurons and thus alters the memory itself.

To explore this explanation, the researchers used optogenics on mice: that is, they implanted fibre optics into their brains so they could deliver light signals. The mice had been genetically modified so that not only did the neurons that were actively forming a memory glow red, but they became responsive to the light signals.

The researchers then put the mice into a new environment (depicted above as the blue box) and tracked which neurons were being used to form a memory of the environment.

Next the researchers put the mice into a new environment (the “red box”) and used the light to activate those specific neurons, thus causing them to remember the first environment. While this was happening, the mice were given mild foot shocks.

The final stage of the test involved putting the mice back into the first environment. The mice showed signs of fear, which the researchers believe was caused by a “memory” of receiving the foot shocks in that environment, something that never actually happened and was a manipulation of the “real” memory of being there.

While it’s very much a first step, establishing the principle that memories can be altered in this way could take us closer to more complicated brain treatments. Examples cited by academics speaking to the BBC include altering the very real memories of people suffering post-traumatic stress disorder, or removing or modifying the false memories of people with schizophrenia.

(Sadly we’ve been unable to get any response to the development from staff at Lacuna Inc.)