There is a connection between circadian rhythm and aggression, study finds

A team of researchers partly funded by NHLBI discovered a circuit in the brains of mice connecting circadian rhythm to aggressive behavior. The findings are of particular interest to Alzheimer’s patients, 20 per cent of whom experience increased bewilderment, anxiety, unease, disorientation, irritation and aggression when the sun sets.

The phenomenon affecting Alzheimer’s patients is called 'sundowning' or sundown syndrome. In the worst case scenarios, the persons need professional care, as it can be difficult for family members to handle. The cause of the condition is unknown, but previous research has suggested that it is connected to the circadian rhythm, and the current findings, published by the journal Nature Neuroscience, confirm it.

According to the paper, the researchers have developed special protein tools capable of turning off the cells in the brain causing the aggressive behavior.