Tests on mice have shown that when a person is scared, a certain part of the brain (the amygdala, present in all vertebrates, including humans), which is responsible for strong emotional reactions, strongly intensifies its activity. This part of the brain depends on the existence of a protein in nerve cells.
By producing this protein, the amygdala remains passive to external stimuli. Researchers believe that in this way extreme feelings will be forgotten without permanently damaging the brain, as it happens in case of lobotomies for example. It said though that the medicine can make recent memories (24, 48 hours) be forgotten.
This experiment is not far from the one featured in the movie “Total Recall” and other sci-fi with similar subject, where all of a person’s memories could be erased.
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