Dr. Winrich Freiwald Uncovers Possible Origin Of Human Speech
One important distinction between humans and other animals is that humans have the ability to speak. Most animals can communicate with noises and gestures, but conversing with verbal language is a skill unique to us. Where did our ability to speak evolve from, and how do our brains make it happen?
Scientists at The Rockefeller University led by NYSCF – Robertson Investigator and Professor of Neurosciences and Behavior Winrich Freiwald, PhD, have identified neural circuitry in monkeys that could represent a common evolutionary origin for social communication. The research is published this week in the journal Neuron.
Using a novel experimental setup, the researchers took MRI scans of the brains of monkeys as they watched video clips of other monkeys making communicative facial expressions.
The team expected that first, the monkey’s face-perception regions would activate, followed by their emotion centers, and then the region of the brain that produces facial expressions. While all of those areas activated, they didn’t follow the expected pattern.
And when the subject monkeys made direct eye contact with the monkey on video, another unexpected neural circuit showed activity, suggesting that specific areas of the animals’ brains are sensitive to social context.
When the subject monkeys saw video of other monkeys meeting their gaze and smacking their lips towards them in friendship, they would mimic the gestures. While they mimicked, the subject monkeys showed activity in the brain regions responsible for social context and information processing. Importantly, they also showed activity in Broca’s area, the brain region responsible for speech in humans. This suggests that facial expressions like lip-smacks might be an evolutionary precursor to human speech.
For more information about this study, check out this article from The Rockefeller University.