Australian scientists have made an "exciting" discovery about the human brain that they say could lead to new treatments for numerous mental health conditions such as depression and post-traumatic stress disorder.
A mouse study conducted by researchers at the Queensland Brain Institute, published in the journal Molecular Psychiatry, found that the adult brain can regenerate new nerve cells in the amygdala - the region responsible for producing feelings of fear and dread.
"Finding ways of stimulating the production of new brain cells in the amygdala could give us new avenues for treating disorders of fear processing, which include anxiety, PTSD and depression," said Dr Dhanisha Jhaveri a senior research fellow at the University of Queensland's Brain Institute.
The amygdala is found deep inside the brain and it plays a key role in controlling the way people react to certain stimuli or an emotional event that is viewed as potentially threatening or dangerous. This is known as fear learning, explained Dr Jhaveri.
"Fear learning leads to the classic flight or fight response - increased heart rate, dry mouth, sweaty palms - but the amygdala also plays a role in producing feelings of dread and despair, in the case of phobias or PTSD, for example," Dr Jhaveri said.
The amygdala has long been implicated in disorders such depression and anxiety. What was not known, until now, was that neurogenesis - the growth and development of nerve tissue - occurs in the amygdala.
"Excitingly this is the first time that new cells have been discovered in the amygdala," said lead researcher Professor Pankaj Sah.
The researchers are now working to fully understand the functional significance of these new neurons in the amygdala in the hope of finding a way to change the brain circuitry in those with PTSD, Dr Jhaveri said.
"The goal for us is to understand what these neurons are doing. Once we have that understanding that certainly would help to develop strategies to prevent or at least alleviate the activation of this brain area which happens in PTSD and anxiety."
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