A study in the 1960s led some neuroscientists to conclude that specific brain cells light up at the sight of one’s grandmother. As one would expect, other scientists immediately dismissed the grandmother neuron as they didn’t think the presence of a grandmother could activate any neuron. However, new research shows that the grandmother neuron might exist.
A study on monkeys has found that a particular area of their brains responds to familiar faces. Furthermore, this brain region has three times the number of brain cells to react to familiar faces than unfamiliar ones.
According to a professor of neuroscience and behavior at the Rockefeller University, New York, Winrich Freiwald, while these cells do not specifically recognize a person’s grandmother, the idea is similar as they have they both have traits of memory and vision. The ability of the grandmother neuron to code for certain information comes from sensory neurons and is kept in memory.
How researchers conducted the study
Researchers examined the temporal lobe and other regions which could be responsible for facial recognition. Then, as two rhesus monkeys looked through the images of human faces, other monkeys, and random objects, they scanned their brains using an fMRI scan.
The team placed electrodes at the temporal lobe and the area responsible for facial recognition to look at the activity of the brain cells as the monkey looked through the images.
Scientists recorded activity in both regions whenever the monkey saw a familiar image. In addition, the temporal lobe lit up three times more familiar objects than unfamiliar objects. These findings confirm that there is a particular region in the brain that recognizes familiar faces.
The monkey reacted in a different way when pictures were blurred
When the team blurred some of the images, the response from the monkeys was different. The brain cells in the temporal lobe barely responded when the photos were obscured but not on familiar faces. The cells appeared to function as both memory and sensory cells. However, the researchers point out that they are not grandmother neurons. The researchers believe they can now try to understand how the area encodes familiar faces.