It may also explain why primates are so good at facial recognition, and how we can potentially identify billions of different people without needing an equally large number
of face cells.
However, the role of such
face cells in social cognition remains unclear.
The researchers dubbed these regions face patches; the neurons inside, they
called face cells.
It may also explain why primates are so good at facial recognition and how we can potentially distinguish among billions of different people without needing an equally massive number
of face cells.
Understanding the facial code in the brain could help scientists study
how face cells incorporate on other identifying information, such as gender, race, emotional cues and the names of familiar faces, he says.
Understanding the brain's facial code could help scientists study how
face cells incorporate other identifying information, such as sex, age, race, emotional cues and names, says Adrian Nestor, a neuroscientist at the University of Toronto, who studies face patches in human subjects and did not participate in the research.
It's a result of
specialised face cells in the brain responding to non-face objects that share certain feature with faces, he says.
It was a revelation to see that each cell indeed has a 49 - dimensional null space; this completely overturns the long - standing idea that
single face cells are coding specific facial identities.
In other words, they could show a monkey a new face, measure the electrical activity of
face cells in the brain, and recreate the face that the monkey was seeing with high accuracy.
«Tsao's work provides the first specific hypothesis for how the response
of face cells in the cortex can be utilised by cells in the hippocampus to form memories of individuals we've seen before,» says Ueli Rutishauser at the Cedars - Sinai Medical Center in Los Angeles.
Gross resisted calling these neurons «
face cells» or «hand cells.»
«The values of each dial are so predictable that we can re-create the face that a monkey sees by simply tracking the electrical activity of
its face cells.»
The researchers found the firing rate of
each face cell corresponds to separate facial features along an axis.
Each face cell was tuned to one of the 50 axes previously identified, Tsao and Chang found.
The researchers then investigated how neurons reacted to different aspects of emotions, and how the activity of
the face cells related to the decision made by the subjects.
They discovered that each of
the face cells is tuned to view faces in slightly different ways — as if photographing a face from multiple angles at once.
Using this code, we are able to reconstruct the face the monkey saw and predict responses of
face cells to an arbitrary face.»
«
The face cells we are studying are at the highest level of the visual system,» Steven Le Chang, a researcher on the project, told Digital Trends.