Science fiction has already flirted with an idea as disturbing as it is fascinating: the possibility of sharing thoughts and emotions. For example, in X-Men , Professor Charles Xavier uses his ” Cerebro ” machine to detect mutants all over the planet and speak to them telepathically. And in Avatar , the Na’vi connect with Eywa (something similar to a collective consciousness) through the biological network on the moon Pandora to transmit feelings to each other.

But there are also less friendly versions. The Mind Flayer in Stranger Things controls the rest of the Upside-Down creatures through a hive mind . And in Game of Thrones , the Night King controls thousands of White Walkers with a very “bad vibe . “

A shared reality

It turns out that real science has been based on science fiction and has been “following the white rabbit” to explore, since 2002 , whether our brains can synchronize. Dutch neuroscientist Suzzane Dikker is a leading figure in this field. But it was psychoanalyst Carl Jung who introduced the concept of ” synchronicity ” into clinical practice (whose interpretations, paradoxically, are far removed from science ).

Since studying a single human brain is not enough to fully understand the neural mechanisms that underpin our social behaviors, several investigations have adopted an approach based on the dynamic interaction between multiple brains: so-called second-person neuroscience .

At the heart of this perspective is hyperscanning , a methodology that allows the brain activity of two or more people to be recorded as they interact with each other (similar to that used to train Jaeger robot pilots in the film Pacific Rim ).

Thus, it has been shown that brains can coordinate as if they were acting in unison. This synchronicity, while opening new avenues for understanding social interaction disorders such as autism and various psychiatric disorders , is not a superpower. Some call it connection, feeling , chemistry, etc., and even those who attribute it to pseudoscientific beliefs such as “energies” or “cosmic vibrations.”

In fact, synchrony is an inherent capacity of the human brain. It has been proven that neurons located in equivalent brain regions in two people fire simultaneously.

So the question arises: would it be unreasonable to talk about a collective mind? For now, we can scientifically confirm that ” being on the same wavelength ” turns out to be more than just an expression. Get some popcorn ready.

Hyperscanning the brain

One method used in second-person neuroscience is functional near-infrared spectroscopy ( fNIRS ) hyperscanning . This noninvasive technique offers several advantages for cognitive neuroscience compared to other modalities used for hyperscanning. For example, it doesn’t require the subject to remain still, as MRI and magnetoencephalography do ; and it has better motion tolerance than EEG .

fNIRS simultaneously records the external neural activity of two or more people as they interact in real time. To do this, everyone involved is fitted with a device with multiple sources and detectors, with the goal of “mind-reading” (like the Sorting Hat in Harry Potter , but with a technological twist). It’s usually a cap attached to the scalp.

fNIRS neuroimaging system. Wikimedia Commons , CC BY

The device records changes in blood oxygenation while the subjects perform a task, emitting a continuous wave of infrared light and measuring the resulting light intensity . Since the areas that absorb the most light are those with the highest oxygenated hemoglobin, this is taken as an indication of greater neuronal activity.

Thus, similar conclusions have been obtained in multiple contexts:

• A study published in Nature (2019) revealed that when teachers and students are physically synchronized, their brains tend to align during educational interactions. This neural synchronization could be linked to greater effectiveness in the teaching-learning process (a practical social bond that could also be applied to music ).
• In sports, research involving basketball players in 2020 provided the first evidence of brain synchrony leading to improved cooperative behavior in a team sport. These results could be key to understanding how teams achieve almost automatic rapport during the game.
• Even in more intimate emotional contexts, such as romantic relationships, greater synchronization has been detected in the most sincere couples (a phenomenon not found in other types of couples, as also corroborated by a recent electroencephalography study). Furthermore, when they share collaborative tasks, such as drawing , their brains also synchronize. These results could help explain the bond that exists between the strongest couples.

The stars of the film

Thanks to hyperscanning studies, we can see in real time the brain regions that are activated inside the head ( inside ) according to social interactions outside ( outside ), something similar to what happens in the brain of the girl protagonist in the Pixar film Inside Out . In this scenario, several structures shine as the stars of the social brain (although much research remains).

The main prize goes to the regions associated with the so-called mirror neuron system . Shared activation patterns have been recorded in these neurons between participants interacting, collaborating, or simply observing each other. The main hypothesis is that they help decode actions performed by other people’s body parts to detect their targets and subsequently act in synchrony.

But the neural substrates that support simple observation differ from those involved in social interaction. Therefore, “mentalizing” networks (or theory of mind networks ) are also involved.

That is, it is a collaborative mechanism : while mirror neurons initially reflect in our brain what we observe, mentalization networks then allow us to interpret why someone acts in a certain way, what their intentions are, or how they feel.

Along with these networks, the cerebellum is also involved, due to its role as a predictor of movements during mutual interactions. Other regions worth mentioning are the anterior cingulate cortex and the anterior insula, both crucial to the phenomenon of self-awareness .

Thinking about the collective mind

In the future, we don’t know if it will be possible to implant thoughts and beliefs like those in the movie Inception . What we can say is that looking , listening, and paying attention facilitate greater interbrain synchrony, which is linked to better performance in collaborative tasks. And that arguments and disagreements unbalance the brain, generating stress and fatigue.

If real science evolves to provide us with solid evidence of a collective mind like that offered by science fiction, the people responsible for this research will undoubtedly be candidates for the Oscar. Sorry, the Nobel.

Author Bio: Jorge Romero-Castillo is Professor of Psychobiology and researcher in Cognitive Neuroscience at theUniversity of Malaga