Researchers uncover brain pathway linked to impulsive behaviours

Researchers from Singapore and South Korea have uncovered new details of a brain pathway that can cause impulsive behaviours.

Using mice, the research team led by Professor George Augustine from Nanyang Technological University, Singapore, discovered that impulsive behaviour is triggered when the brain signalling chemical dopamine is passed to an unexpected area of their brain.

To trace the pathway that dopamine signals take to produce an impulsive action, Prof Augustine and his team used mice that had a specific set of dopamine receptors genetically removed, making their brains unable to detect dopamine signals.

The researchers artificially activated these receptors in specific parts of the brain, and the mice displayed impulsive behaviour when the signal was picked up by the amygdala – an almond-like structure deep in the brain.

“We have shown for the first time that impulsive behaviour in mice is only triggered when dopamine signals are received and passed on to an unexpected part of the brain – from the amygdala to the BNST,” said Prof Augustine, a neuroscientist at NTU Singapore’s Lee Kong Chian School of Medicine (LKCMedicine).

The study was published in Proceedings of the National Academy of Sciences of the United States of America (PNAS).