Yale University Scientists Activate Killer Instinct In Mice Using LasersBy Emily Marks, UniversityHerald Reporter
Yale University researchers were able to isolate the part of the brain that coordinates predatory hunting. Two sets of neurons found in the amygdala, the part of the brain that controls emotion and motivation, cue the animal to turn predatory as well as use its jaw and neck muscles to bite and kill.
Phys.org reported that the scientists used optogenetics to only turn on specific set of neurons. Optogenetics uses light stimulation to activate specific neurons.
When the laser is turned off, the mice behave normally. However, when it was turned on, the mice were found to pursue and bite anything in their way.
Ivan de Araujo, who led the study, said that the mice jumped on an object right after the laser was turned on. It looked like the animal was trying to capture it and kill it. De Araujo is an associate professor of Psychiatry at the Yale University School of Medicine as well as an associate fellow at the John B. Pierce Laboratory.
Interestingly, the mice did not attack others of the same species in the cage. Moreover, hunger did affect predatory behavior, with hungry mice being more aggressive than those who were not hungry.
According to The Washington Post, de Araujo clarified that they were not trying to create a monster. He said that the study was focused on understanding how large brain networks work.
Science Magazine noted that the lead investigator got inspiration from a 2005 study that claimed how the amygdala was active during hunting and feeding in rats. It seemed off at the time since most research about that part of the brain was about defensive or submissive emotions.
Since the mice did not attack other mice in the cage, de Araujo added that it is highly likely that other parts of the brain may be helping keep the amygdala in check. Kay Tye, a neuroscientist at Massachusetts Institute of Technology in Cambridge, suggested that the fear and hunting centers may have been found in the same part of the brain because they are related when it comes to living in the wild.