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Scientists find key to unwanted thoughts
Researchers found a particular chemical, or neurotransmitter, known as Gaba, held the key. Gaba is the brain's main "inhibitory" neurotransmitter. That means, when it's released by one nerve cell it suppresses the activities of other cells to which it is connected.
They found people who had the highest concentrations of Gaba in their brain’s hippocampus (or memory hub) were best at blocking unwanted thoughts or memories.