We could erase unpleasant memories by flicking a switch, scientists said.

Researchers from KU Leuven in Belgium and Leibniz Institute for Neurobiology in Germany discovered that memories could be erased using a "genetic switch."

In the study, which was published in Biological Psychiatry, the researchers used mice that had been genetically modified in one single gene, neuroplastin, which is important in brain plasticity.

According to the study, changes in the regulation of neuroplastin has recently been linked to decreased intellectual abilities and schizophrenia.

During the research, the mice were trained to move from one side of the room to another when a lamp lights up. This conditioning process is called associative learning, which, when applied to humans, is somewhat the same as when students in a classroom feel suddenly hungry after hearing the lunch bell.

But when the scientists switched off the neuroplastin gene, the mice were no longer able to perform the task properly. According to the researchers, the mice showed learning and memory problems related to associative learning.

By contrast, the mice with the gene still on were able to carry on with the task perfectly.

"We were amazed to find that deactivating one single gene is enough to erase associative memories formed before or during the learning trials," Detlef Balschun from the KU Leuven Laboratory for Biological Psychology and study author said in a press release.

"Switching off the neuroplastin gene has an impact on the behavior of the mice, because it interferes with the communication between their brain cells," Balschun added.

The KU Leuven team measured the electrical signals in the brain and discovered deficits in the cellular mechanism used in storing memories. The changes are still visible at the level of individual brain cells, the researchers said.

"This is still basic research," Balschun said. "We still need further research to show whether neuroplastin also plays a role in other forms of learning."