Is aggressive behavior contagious?

Photo by Andrea Piacquadio via Pexels

By Stephen Beech

Aggression can be contagious, suggests new research.

People who repeatedly observe aggressive behavior have a higher likelihood of engaging in violent behavior themselves, scientists say.

Researchers at Southern University of Illinois School of Medicine in the United States used mice to explore the environmental factors and neural mechanisms that lead to the aggression that witnesses later acquire.

In an experiment created by the research team, mice observed known peers or unfamiliar strangers attack intruder mice.

Only male witnesses later displayed increased aggression themselves, and that happened only after watching familiar peers attack intruders.

The researchers recorded activity from neurons in a part of the amygdala