Scientists have turned wimpy mice into ferocious hunters by zapping their brains with a laser.
Using optogenetics, a technique that makes specific neurons fire when stimulated with light, the scientists activated a set of neurons in the amygdala.
The amygdala, a small region within the brain, is associated with memory, emotions – including fear – and motivation. A paper
published in
Cell on Thursday shows the amygdala can be manipulated to make mice immediately aggressive.
When the laser is off, the lab mouse acts normally, preferring to walk around its cage and occasionally sniff the air. But when the laser is turned on, beast mode is triggered and the mouse pounces on and bites moving bug toys and live insects, as well as inanimate objects like wooden sticks and bottle caps.
"We'd turn the laser on and they'd jump on an object, hold it with their paws and intensively bite it as if they were trying to capture and kill it,"
said lead investigator Ivan de Araujo, coauthor of the paper and associate professor of psychiatry at Yale University.
Araujo compares the predatory behaviour to how "walkers" from American zombie TV hit series,
The Walking Dead, act.
