(NaturalNews) In a number of disturbing recent studies, scientists have shown the power to create and erase memories "at will."

Most recently, in a study conducted by researchers from the University of California-San Diego (UCSD) and published online in the journal Nature on June 1, researchers were able to erase specific memories from the brains of rats, then later reinstate them.

"We can form a memory, erase that memory and we can reactivate it, at will," senior author Roberto Malinow said.

Creating fear

As in many memory studies, researchers used rats that had been genetically modified to make their brain cells sensitive to light. The researchers bombarded the rats' brains with light, while at the same time delivering a painful electric shock. The researchers continued this practice until stimulation of the nerve cells alone was enough to produce a fear response.

The researchers then used a separate series of memory-suppressing optical pulses to stimulate the same nerves. When the nerves were re-stimulated in the original fashion, the rats no longer showed fear.

Then the researchers stimulated the nerves with yet another series of optical pulses, these designed to help memories form. The rats once more showed a fear response when the original stimulation was repeated.

Lead author Sadegh Nabavi exulted over the ability to control the brain's fear centers.

"We can cause an animal to have fear and then not have fear and then to have fear again by stimulating the nerves at frequencies that strengthen or weaken the synapses," Nabavi said.

Total Recall?

In a study published in the journal Biological Psychiatry in September 2013, researchers from the Florida campus of The Scripps Research Institute were able to deliberately erase specific memories in the brains of mice and rats. They did this by inhibiting the action of certain molecules in the brain during the maintenance of memory formation. The researchers claimed that tests showed that no memories other than those targeted were affected by the procedure, although of course this cannot be proven.

Memory researchers are promoting such studies as a potential boon to those suffering from drug addiction or post-traumatic stress, ignoring the implications of such technology if used non-consensually.

"Our memories make us who we are, but some of these memories can make life very difficult," said Courtney Miller, lead researcher of the Florida study. "Not unlike in the movie Eternal Sunshine of the Spotless Mind, we're looking for strategies to selectively eliminate evidence of past experiences."

Perhaps even more chillingly, a July 2013 article in the journal Science featured findings from an MIT study that demonstrated a method for creating false memories. Researchers created an association in the brains of mice between being in a specific room, optical nerve stimulation, and an electric shock. The mice were then moved into a separate room, where the same nerve was stimulated. When the mice later returned to this room, they acted as if they remembered receiving an electric shock there.

"Whether it's a false or genuine memory, the brain's neural mechanism underlying the recall of the memory is the same," researcher Susumu Tonegawa said.

This memory manipulation appeared to interfere with the mice's memory of the original room, however. Mice whose memories had been tampered with did not show as much fear of the room where they had actually experienced the shock as mice whose memories were intact.

"Now that we can reactivate and change the contents of memories in the brain, we can begin asking questions that were once the realm of philosophy," lead author Steve Ramirez said.

"These are the once seemingly sci-fi questions that can now be experimentally tackled in the lab."

Sources for this article include:

http://www.sciencedaily.com/releases/2014/06/140601150633.htm

http://www.sciencedaily.com/releases/2013/09/130910140941.htm

http://www.sciencedaily.com/releases/2013/07/130725141711.htm