Self-Motivation
David Goggins
Former Navy Seal
Career Development
Bryan Cranston
Actor
Critical Thinking
Liv Boeree
International Poker Champion
Emotional Intelligence
Amaryllis Fox
Former CIA Clandestine Operative
Management
Chris Hadfield
Retired Canadian Astronaut & Author
Learn
from the world's big
thinkers
Start Learning

This brain balancing act allows consciousness

Two types of thinking have a time-sharing deal going on in your brain.

Image source: paulaphoto/shjk/Big Think
  • Your DMN and DAT neural networks cooperate by staying out of each other's way.
  • FMRI scans reveal a surprising temporal dance.
  • When both systems are at the same activity level, boom, you're unconscious.

While consciousness remains "the hard problem" — as in what exactly is it? Where is it? — a new study published in Science Advances sheds surprising light on how the brain switches us from conscious to unconscious states and vice versa. It has something to do with an imbalance between two neural systems. In fact, consciousness requires that imbalance.

Imagine you and a friend want to go out to dinner but you want Chinese food and your friend wants pizza. If both of your preferences carry equal weight, nobody gets to eat. Let's say that's like unconsciousness. But when one of you gives in, yum: Consciousness.

According to lead author Zirui Huang of University of Michigan Medical School, "Studies have shown that the anti-correlation of the two networks is vital for maintaining ongoing interaction between self and the environment, [and] that contributes to consciousness."

Seesaw

Image source: Gearstd/Shutterstock/Big Think

The two neural networks are the default mode network (DMN) and the dorsal attention network (DAT).

The DMN is an internally directed neural system that exhibits electrical activity in fMRI scans when you're awake and the brain is comparatively at rest and not at work performing a specific task. Maybe you're spacing out, or reflecting on something, or maybe you're enjoying a memory of some sort.

The DAT lights up when your brain is actively directed externally toward accomplishing a specific task; it's sometimes called the "task -positive system."

The scientific term for their relationship is that they're "anti-correlated," and the maintenance of their opposite states is a consistent thing, so some kind of temporal relationship seems implicit.

Nighty-night

Image source: Hakaba/Shutterstock

The implied temporal relationship has not previously been definitively shown to impact consciousness. Huang's study, however, tests the idea that this anti-correlation is a requisite for consciousness, or maybe it's the other way around: Absent consciousness, the anti-correlation breaks down.

To test their hypothesis, Huang and his colleagues analyzed resting-state fMRI scans from 98 participants in varying states of responsiveness, located in Shanghai and Wisconsin. (Because participants were given task in various states, the researchers chose to grade their level of unresponsiveness instead of unconsciousness." In addition to a DAT-mode control group, scans were performed on participants who were in unresponsive states from anesthesia, either propofol or ketamine, or from unresponsive wakefulness syndrome, or UWS. Ultimately, the researchers developed four data sets: propofol-Shanghai, propofol-Wisconsin, ketamine, and neuropathological patients.

They found being unresponsive correlated consistently with scans in which the DAT and DMN systems were at equilibrium. No Chinese food or pizza for them.

For confirmation, a second study was performed with scans from 248 subjects published in the OpenfMRI database. The cohort consisted of healthy individuals, as well as individuals with psychiatric disorders including schizophrenia, bipolar disorder, and attention deficit/hyperactivity disorder. Various states of responsiveness in the available scans were identified, and once again, when DAT and DMN activation was equal, participants were in an unresponsive state.

Part of a larger mystery

DMN imagery

Image source: John Graner/Wikimedia

Of course, this study doesn't get us much further along regarding the hard problem, but we do now know a little bit more about how consciousness appears to work at least. The DMN and DAT neural networks together account for a lot of what goes on it consciousness. Just, please, not at the same time.

LIVE ON MONDAY | "Lights, camera, activism!" with Judith Light

Join multiple Tony and Emmy Award-winning actress Judith Light live on Big Think at 2 pm ET on Monday.

Big Think LIVE

Add event to calendar

AppleGoogleOffice 365OutlookOutlook.comYahoo

Keep reading Show less

Neom, Saudi Arabia's $500 billion megacity, reaches its next phase

Construction of the $500 billion dollar tech city-state of the future is moving ahead.

Credit: Neom
Technology & Innovation
  • The futuristic megacity Neom is being built in Saudi Arabia.
  • The city will be fully automated, leading in health, education and quality of life.
  • It will feature an artificial moon, cloud seeding, robotic gladiators and flying taxis.
Keep reading Show less

Your emotions are the new hot commodity — and there’s an app for that

Many of the most popular apps are about self-improvement.

Drew Angerer/Getty Images
Personal Growth

Emotions are the newest hot commodity, and we can't get enough.

Keep reading Show less

Study details the negative environmental impact of online shopping

Frequent shopping for single items adds to our carbon footprint.

A truck pulls out of a large Walmart regional distribution center on June 6, 2019 in Washington, Utah.

Photo by George Frey/Getty Images
Politics & Current Affairs
  • A new study shows e-commerce sites like Amazon leave larger greenhouse gas footprints than retail stores.
  • Ordering online from retail stores has an even smaller footprint than going to the store yourself.
  • Greening efforts by major e-commerce sites won't curb wasteful consumer habits. Consolidating online orders can make a difference.
Keep reading Show less
Future of Learning

The key to better quality education? Make students feel valued.

Building a personal connection with students can counteract some negative side effects of remote learning.

Scroll down to load more…
Quantcast