Surrounded by technology and urbanity though we may be, the human brain remains profoundly hard-wired to respond to animals.
When people are shown pictures of animals, specific parts of the amygdala — a structure central to pleasure and pain, fear and reward — react almost instantly.
Put another way, glimpsing a bird at the feeder or a shark on Animal Planet, or even a plankitten, could invoke cognitive tricks inherited from ancestors who walked on four legs in shallow water.
The effect is large and consistent, and “may reflect the importance that animals held throughout our evolutionary past,” wrote researchers led by California Institute of Technology neurobiologist Florian Mormann in an Aug. 29 Nature Neuroscience paper.
The researchers had access to a unique group of research subjects: 41 people receiving surgery for drug-resistant epilepsy. Prior to surgery, doctors needed to map their minds, a task performed by inserting electrodes into different parts of their brains, then measuring neuron-by-neuron responses to stimuli.