If you are an inquisitive person, you may have wondered how you can recognize familiar people, even when you have not seen them in years. Well, you are not the only one. For a long time, scientists have been on a finding quest to know what could be responsible for this phenomenon, and not until recently, the answer has been more hypothetical than real. However, a recent breakthrough, which even though it did not fully answer the question, was quite encouraging and will enable scientists to be more precise in this search.
A grandmother cell
Previously in the science world, the unsubstantiated tenet was that a cell – the grandmother cell, could be the key to facial recognition. This cell, thought to be the link between perception and memory, was believed to be invoked when we see a familiar face.
Unlike the single-cell grandmother neuron, scientists have unraveled that a group of neurons housed in the temporal lobe of the brain has been the mystic jewel, liable for committing facial recognitions to long-term memory. The discovery was first published in the Science journal, and it elucidated how the faces of our dear ones were ingrained into our brains.
A professor of neuroscience and behavior at Rockefeller University, Winrich Freiwald, had once let us know that, in his early years in neurosciences, the grandmother neuron was a term used to describe a hypothesis that is not expected to exist. Now, we have found something related to the grandmother neurons, cells that can bridge facial recognition with memory.
In a previous attempt to solve the puzzle of facial recognition and its conversion to memory, the 1960’s one-to-one ratio thesis of a single neuron for each concept or perception came to light. When it was believed that the grandmother cells were abstract brain cells that could inoculate and process a particular concept on their own. One responsible for recognizing the grandmother, one for the grandfather, and so on.
However, scientists have rather discover a functional constellation of sensory neurons capable of facial recognition, and as a group, processing and storing as many personal events as possible. In contrast, the grandmother prototype that simply connected vision to memory never came forth as expected. Freiwald and his team had recently discovered that it is just a part of the brain’s temporal pole (TP) that could be responsible for facial recognition, and they dug further by using functional magnetic resonance imaging to navigate and elaborate on the TP areas of two rhesus monkeys. And while the monkeys watched pictures of people they have seen in person, and people they have only seen virtually, the electric signals were recorded.
The cells in the TP region were noted to have responded quicker, and threefold stronger to familiar faces than to unfamiliar faces, even when they have seen the unfamiliar ones multiple times on the screen.
With the discovery of these cells, which act as both sensory and memory cells, this experiment proves the importance of knowing someone in person, and how it relates to our brain’s perception of them. And with recent developments and the propensity of going virtual, it is noteworthy that we understand that the on-screen faces may not elicit the same response as those we have met.