Disagreeing Takes Up A Lot Of Brain Real Estate Compared To Agreeing, Study Reports

Researchers from Yale University have studied the brains of two people simultaneously while they were engaged in a discussion. The result is quite surprising.

When two people are on the same note of agreeing on something their brains exhibit a calm synchronization of activity focused on sensory areas of the brain.

However, when they disagree, many other regions of the brain are involved in higher cognitive functions as each region combats the other’s argument.

The research team reported on Jan 13 in the journal Frontiers of Human Neuroscience.

Joy Hirsch, senior author and Professor of Psychiatry and professor of comparative medicine and neuroscience said that our entire brain is a social processing network which takes a lot more brain real estate to disagree than to agree.

The study recruited 38 adults who were asked to say whether they agreed or disagreed on a series of statements. They then matched pairs based on the responses and used an imaging technology called functional near-infrared spectroscopy to record their brain activity while they engaged in face-to-face discussions.

It showed that when people agreed, the brain activity was harmonious and concentrated on sensory areas of the brain such as the visual system. However, during a disagreement, these areas of the brain were less active. Their activity in the brain’s frontal lobes, home of higher-order executive functions seemed to increase.

They added that there is clear synchrony between brains when they agreed, but when they disagreed, these neural coupling seems to disconnect.

Hirsch also said that understanding how our brains work while such agreements and disagreements in a polarized political environment are particularly important.

She concluded by saying that two brains engage many emotional and cognitive resources “like a symphony orchestra playing different music.” In agreement, there “is less cognitive engagement and more social interaction between brains of the talkers, similar to a musical duet.”

Journal Reference:
Joy Hirsch, Mark Tiede, Xian Zhang, J. Adam Noah, Alexandre Salama-Manteau, Maurice Biriotti Interpersonal Agreement and Disagreement During Face-to-Face Dialogue: An fNIRS Investigation Front. Hum. Neurosci., 13 January 2021 DOI: 10.3389/fnhum.2020.606397

Press Release: Yale University