Brain laser sparks ‘killer’ predatory instinct in mice

The neurological source of hunting instincts may originate from two teams of neurons nestled deep in the forebrain of most vertebrates, according to a new study published in the journal Cell.

In the study, researchers found triggering these specific sets of neurons located in a section of the brain known as the amygdala prompted mice to go after prey and to nip at everything in their path, even twigs and bottle caps.

“This area, the central amygdala, seems to allow the animal precise control over the muscles involved in pursuing and capturing prey,” study author Ivan de Araujo, associate professor of psychiatry at Yale University, said in a press release.

Firing Lasers at the Brain

The study team used a light-based method known as optogenetics to activate neurons of the central amygdala, a part of the brain associated with emotions and motivation. They discovered that one group of neurons caused mice to go after moving objects while a second group of neurons appeared to switch on jaw muscles related to biting. Furthermore, the mice jumped on inanimate objects and bit them when both groups of neurons were triggered, the researchers said.

Triggering these neurons also boosted the effectiveness with which mice searched for and captured live insects. The two groups of neurons appear to function as exchange stations that induce hunting behavior after the animal picks up visual cues of nearby prey.

These areas of the amygdala are found in nearly all vertebrates, a sign of their evolutionary significance, the researchers said. Oddly enough, these areas appear to be missing in brains of some species like lampreys, which have no jaws, de Araujo mentioned.

“It is a major evolutionarily player in shaping the brain,” the Yale researcher said. “There must be some primordial subcortical pathway that connects sensory input to the movement of the jaw and the biting.”

The study team also noted that stimulating these neurons did not cause the mice to attack other mice.

“The system is not just generalized aggression,” de Araujo said. “It seems to be related to the animal’s interest in obtaining food.”

—–

Image credit: Ivan de Araujo/Cell Press

The post Brain laser sparks ‘killer’ predatory instinct in mice appeared first on Redorbit.

redOrbit.com
offers Science, Space, Technology, Health news, videos, images and reference information. For the latest science news, space news, technology news, health news visit redOrbit.com frequently. Learn something new every day.”