Positive brain frames

A startling one in six adults in the UK are on antidepressants at any one time. A new study discovers how these drugs revert the brain into a more flexible state, reminiscent of the teenage brain. This might help the brain build new, more positive, frameworks for processing environmental cues. This finding, in mice, may pave the way for developing new depression treatments with fewer side effects for humans.  

Antidepressant treatments like Prozac, were developed in the 1970's and increase the available amount of the brain chemical serotonin: this increases feelings of reward and pleasure. However, it's previously eluded scientists how the drugs affect brain cell structure.

Published this week in Molecular Brain, Japanese researchers Miyakawa and colleagues administered Prozac to adult mice for three weeks. They then looked in their brains and found significantly elevated rates of new nerve cells being born in the hippocampus, a brain region involved in learning and memory. In the prefrontal cortex, the region behind the forehead involved in processing information and making decisions, there were decreased amounts of a protein called parvalbumin which indicates nerve cell maturity.

Together, these findings indicate the antidepressant Prozac reverts the adult brain to a more teenage state, with higher levels of plasticity and flexibility. If the same holds true for humans this might help alleviate symptoms of depression by fostering the ability of the brain to evaluate scenarios in a new more positive light, rather than using existing frameworks that may entrench negative emotions.

Antidepressants can have significant side effects, including insomnia, increased risk of suicide and decreased libido. These results may pave the way to new treatments for depression.