BB #71: Brain Background

Initially I thought, for the first time in the the Brain Bubbles series, I have a bubble actually related to the brain. When I went through the list, though, I saw that #17, Pointers!, was about the brain-mind problem, although the ideas expressed there were very speculative.

As is usually the case when talking about the mind and consciousness, considerable speculation is involved — there remain so many unknowns. A big one involves the notion of free will.

I just read an article that seems to support an idea I have about that.

The article, which I saw in Salon (dot com), is Most brain activity is “background noise” — and that’s upending our understanding of consciousness, by Thomas Nail, Professor of Philosophy at the University of Denver.

The article starts off with why it can be so hard to answer the question, “What are you thinking about right now?”:

95 percent of your brain’s activity is entirely unconscious. Of the remaining 5 percent of brain activity, only around half is intentionally directed. The vast majority of what goes on in our heads is unknown and unintentional. Neuroscientists call these activities “spontaneous fluctuations,” because they are unpredictable and seemingly unconnected to any specific behavior.

It goes on to compare our minds to ships tossed at sea, and I think we’ve all experienced being at sea mentally, our thoughts seemingly directed every which way.

Nail brings up the question of why our brain, which is just 2% of our body’s mass, uses a whopping 20% of our energy to run a system that produces so much noise.

That seems generally contrary to how evolution works. (Although evolution is certainly not without its excesses and outright mistakes. In some cases, traits selected for sexual desirability put a strain on the animal itself. Think of the giant bills, tails, and plumes, of some birds, for instance.)

Still, it doesn’t seem all that likely a noisy brain would be accidental or a byproduct of an evolutionary misstep. The alternative is that it serves an important purpose.


Let me interrupt here to mention an idea I’ve had for a while now about how our brains might be one of the only non-deterministic physical systems that exist.

In part it comes from their sheer complexity, but a big part of my speculation has been that our minds are filled with background thoughts and mental noise, and that our consciousness is able to sift through and select from that in ways that defy physical determinism.

Ways that seem random physically, but which are driven by our consciousness selecting amid the noise of equally available thoughts.

I’ve spent a lot of time watching my mind as I decide what to have for dinner. Especially in cases where I’ve decided soup sounds good, what causes me to select clam chowder over minestrone or lentil or any of the other varieties I keep in my pantry? (I like soup.)

Determinism claims there is some chain of physicality that inevitably leads to the soup I select. A vexing issue about free will versus determinism is why it feels like I’m making a free choice, especially when I go back and forth trying to pick a soup.

The question is, if reality could be rewound to that moment, could I have chosen a different soup? It feels like that’s possible.

But is it? Is the sense we have of free will an illusion? If it isn’t, what’s the mechanism that provides for it?


Back to the Salon article. Nail writes:

Many brain studies of consciousness still look only at brain activity that responds to external stimuli and triggers a mental state. The rest of the “noise” is “averaged out” of the data.

Then he endears himself with me a bit by mentioning computationalism, a topic I’ve spent a lot of blog posts trying to unpack.

Nail continues:

This is still the prevailing approach in most contemporary neuroscience, and yields a “computational” input-output model of consciousness. In this neuroscientific model, so-called “information” transfers from our senses to our brains.

Then came the part that made me smile:

Yet the pioneering French neuroscientist Stanislas Dehaene considers this view “deeply wrong.” “Spontaneous activity is one of the most frequently overlooked features” of consciousness, he writes. Unlike engineers who design digital transistors with discrete voltages for 0s and 1s to resist background noise, neurons in the brain work differently. Neurons amplify the noise and even use it to help generate novel solutions to complex problems. In part, this is why the neuronal architecture of our brains has a branching fractal geometry and not a linear one. The vast majority of our brain activity proceeds divergently, creating many possible associations and not convergently into just one.

Which, yeah, is very much what I’ve been thinking about the brain. One argument I’ve made repeatedly is that, no, neurons are not like logic gates. They’re much more like signal processors, and rather noisy ones at that.

[Note: The article links to Dehaene’s book. I linked to his Wiki page.]


Nail writes that multiple scientists are addressing the issue of spontaneous fluctuations in a new field “known as the ‘neuroscience of spontaneous thought.’ Several critical studies in this area have shown that cognitive flux, or ‘spontaneous fluctuation,’ is not secondary to but rather fundamental for consciousness.”

Apparently the “frequency and distribution of this flux can even accurately predict whether someone is conscious or unconscious.”

Nail suggests this view could be a game-changer for theories of mind.

As a music lover, I liked the analogies to our minds acting like a jazz band:

Our “metastable minds” are emergent properties of lower frequency fluctuations that conjoin into “nested hierarchies” with higher frequency fluctuations. Neuroscientists call this process “cross-frequency coupling.” It works a lot like syncopation in music. At the lowest frequencies, the drums lay down a beat. In-between these beats, the bass plays a rhythm, and in-between the notes of that rhythm, the guitar plays a melody. The song is a sound-wave made of sound-waves.

I like his stream analogy, too:

In most theories, consciousness is “mission control” perturbed by background noises. But consciousness functions more like an eddy in a river in this new model. Just as whirling patterns emerge from turbulent waters, our stream of conscious thoughts and feelings arise from the torrent of spontaneous brain fluctuations.

He actually gets quite poetic about it:

Our brains respond to these frequencies with their own spontaneous fluctuations. They play between the waves with melodies that make up our thoughts and feelings. Like a jazz trio, the world, body, and brain have their own spontaneous fluctuations that are the basis of the creative improvisation we call existence. The world, body, and brain entrain with one another like interlocking eddies floating down a stream.

At the end of the article Nail explores the idea of this cognitive flux and mental health, which is a topic of extra concern in these COVID-stressed times.

If the recent theories of these fluctuations are correct and consciousness emerges noisily from the bottom-up, this suggests a different mental health treatment model. Over time, spontaneous brain activity can become entrained and coupled into negative perceptions and rigid mental habits that constrain the lower frequencies. Higher frequency brain activity can act as a “filter” on our incoming perceptions and feelings about ourselves and the world. In particular, recent research on cognitive flux shows that depressive and anxious rumination occurs at some of the highest levels of nested activity in a region scientists recently named the “default mode network.”

Which ties into the idea that one can work oneself into depression by constantly playing the same mental grooves. Over time, the brain seems to lock into this mode to the point that, traditionally, anti-depressant drugs are necessary to pull it back to normal.

§ §

I liked this so much I couldn’t help quoting so much of it. The article is much longer though, I haven’t spilled all the beans. It’s good reading for those interested in theories of mind.

Obviously it’s speculative, but it does sound well-grounded to me.

And, just maybe, it provides that mechanism for free will.

Stay mentally noisy, my friends! Go forth and spread beauty and light.

About Wyrd Smythe

The canonical fool on the hill watching the sunset and the rotation of the planet and thinking what he imagines are large thoughts. View all posts by Wyrd Smythe

4 responses to “BB #71: Brain Background

  • Wyrd Smythe

    If you visit Denver, watch out for falling aircraft parts!

  • Wyrd Smythe

    Speaking of noisy brains, there have been some interesting developments with regard to actually communicating with sleepers having lucid dreams:

    I’ve manage to have two lucid dreams, and they were awesome. I keep hoping to have another so I can try to fly.

  • Wyrd Smythe

    (Huh. I’m surprised. I thought this post would get more interest.)

    ION: Apparently, according to one new study, people who curse may be more honest.

  • rung2diotimasladder

    I don’t know about logic gates or signal processors, but Nail’s explanation seems more in line with what we experience too, phenomenologically speaking. One of Husserl’s big points was that we can’t experience the way we do without both the foreground and background of consciousness. Intentionality—the directedness of consciousness—can only occur within a background realm, which is always sitting there, a vaguely experienced ‘outer edge’ of whatever it is we’re focused on, a “something more” that we can possibly explore.

    I like the jazz metaphor too. It gives intentionality something of a boundary without taking away its improvisational nature, its freedom.

And what do you think?

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

%d bloggers like this: