Category Archives: Science

It’s Not the Reactionaries So Much as the Elites They Listen To

Twitter isn’t the best place for reasoned discussion, but depending on who you follow, it isn’t a vast, superficial wasteland either. One of the cool things it offers is the occasional tweetstorm that benefits from directness and immediacy.

Here, slightly edited, is what David Roberts, who writes about climate and energy for Vox, had to say in thirty or so tweets yesterday:

Ever since climate became a political issue in the US, one of the most ubiquitous topics of climate discussion has been “how can conservatives be persuaded to accept climate science and join in the productive search for solutions?” I have read, no joke, MILLIONS of words on that subject. Been following that conversation long enough to notice it has certain recurring features.

The weirdest aspect is that it almost always treats conservatives and their denial as a kind of feature of the landscape, like a mountain. It’s something that just IS, something other people have to maneuver around, or overcome, or otherwise deal with. It is not treated as a CHOICE, made by grown-ass adults who could choose differently, for which they are responsible.

Another (related) weird aspect is, it’s almost always treated as something that the right’s political opponents *caused*. Al Gore caused it. Strident rhetoric or “alarmism” caused it. Enviro aversion to nuclear power (or CCS [Carbon Capture and Storage], or geoengineering) caused it.

It’s always discussed as a result of something enviros or the left did–and something they could undo, if they just acted/talked right. “If environmentalists stopped doing [thing that personally annoys me], they’d be winning over the right” is a *ubiquitous* template.

But it’s bullshit. The question of what shapes conservative opinion is not some deep mystery about which your gut impulses carry any insight. It’s an intensely studied question in social science and has been, as least to a decent approximation, answered. I recommend this post, summarizing John Zaller’s book The Nature & Origins of Mass Opinion. To *very* briefly summarize: people don’t know anything; they don’t have strong opinions on political “issues”; they form opinions by following the cues of leaders in their various social tribes. We are social creatures; tribal ties (not “issues”) are primary.

So conservatives believe what conservatives believe. And they find out what conservatives believe from conservative elites.That means conservative politicians, celebs, and local leaders, but especially, in US conservatism circa 2017, *media figures*. Conservative media plays an *enormous* role in shaping conservative opinion and has dragged it steadily rightward.

So we can say with confidence that conservatives deny climate change because that’s what conservative political/media elites do. Elite cues are what matter. It follows that the *only* reliable way to get conservatives to stop denying climate change is for conservative political/media elites to stop. That’s it.

You might think that Al Gore should STFU, enviros should support nuclear, green journalists should avoid “doomism” and all the other things that VSPs [Very Serious Persons] are always scolding greens for. Fine. Think what you want. Scold away.

But there is no evidence, and no reason to think, that any of those changes would have any material effect on conservative climate denialism. Conservatives will change their tune on climate when the people they see on Fox & Breitbart change their tune. Until then, clever arguments and magic words (“national security!” “conserving God’s gift!”) are futile for everything except meeting think-piece word counts.

Conservative elites and media are to blame for conservative ignorance and obstruction on climate. Not greens, not Democrats, not Al Gore, not That Guy on Twitter. What they are doing is a monstrous crime that will directly result in enormous suffering. And they are grown-ass adults fully capable of understanding the consequences. They are responsible for their own actions and deserve to be called out for them.

Basically, conservative elites are to blame for climate paralysis and only conservative elites can change it. I don’t like it, but there it is. Step one for everyone ought to be telling the damn truth about it. Quit finding “clever,” “counterintuitive” ways to blame others, FFS. As Ornstein and Mann said (more broadly, but it applies here as well), “Republicans are the problem”.

Of course, in the case of global warming, Republicans are only part of the problem. The big problem is global warming itself, combined with how unlikely it is that we will stop it from getting worse. What scientists have predicted for decades is coming to pass. The world is getting hotter; the atmosphere has more moisture in it; the oceans are rising; the ice is receding; the permafrost is melting; storms and heat waves are intensifying. We are polluting the planet to a dangerous degree and it’s coming back to bite us, too quickly for us to stop it, yet too slowly to make everyone feel the urgency of the problem. 

Later, I saw that David Roberts presented his thoughts more formally in an article with a long title: “As Hurricanes and Wildfires Rage, US Climate Politics Enters the Realm of Farce: Climate Denial Is Less Credible, But More Powerful, Than Ever”.

But if you want to get really depressed, take a look at The Guardian‘s “This Is How Your World Could End”. If the author is correct, it’s not out of the question that the earth’s surface may become too hot for mammals. The good news is that many other living things would survive, including birds, who handle heat better than we do.

Darkness in America

I suppose it’s possible there were some “very fine people” who chose to march with the Nazis and Klan in Charlottesville, chanting “blood and soil” and “Jews will not replace us”. Perhaps they were seriously misinformed about the nature of the event. But as Chris Rock said today: “If 10 guys thinks it’s ok to hang with 1 Nazi then they just became 11 Nazis”.

The good news is that the president* sunk so low today that more of our fellow citizens will turn against him, finally seeing him for what he is. His angry defense of white supremacy even generated disgusted reactions from a few of the right-wingers on Fox (order has probably been restored by now).

Congresswoman Gwen Moore, a Democratic Congresswoman who represents Milwaukee, called for his impeachment:

“As we once again hear [the president*] defend those responsible for the deadly riot in Charlottesville and receive praise by hate groups like the KKK and neo-Nazis, the time has come for Republicans and Democrats to put aside our political differences and philosophical debates for a higher cause. For the sake of the soul of our country, we must come together to restore our national dignity that has been robbed by [his] presence in the White House. My Republican friends, I implore you to work with us within our capacity as elected officials to remove this man as our commander-in-chief and help us move forward from this dark period in our nation’s history.”

Of course, impeachment is unlikely, given the Republican majority in the House, but perhaps the House and Senate will vote to censure him. I could see our not-as-terrible-as-some Republican Congressman voting for that. 

Perhaps being censured would finally give our president* the heart attack or stroke he so richly deserves (after his new chief of staff told him what “censure” means). 

Meanwhile, the sun, earth and moon are speeding toward the locations in space that will give America a solar eclipse on Monday. The “totality – the area where the sun is completely blocked by the moon – will be 70 miles wide and will travel from Oregon in the morning to South Carolina in the afternoon. The rest of the country will see a partial eclipse. 

Vox has a cool eclipse tracker that allows you to see when the eclipse will occur in your zip code and how much of the sun will be hidden. At its peak here in New Jersey, 72% of the sun will be hidden at 2:44 p.m. I don’t plan to use the special glass or glasses you need in order to avoid permanent eye damage, but I’ll certainly take a quick look. Coincidentally, I have an appointment with our optometrist at 3 p.m. I can experience the eclipse from his parking lot and then he can tell me if I’m blind.

I’m just brainstorming here, but I wonder if someone could convince our president* that the eclipse will be a Message telling him his presidency is over. Eclipses have often made a big impression on the ignorant and/or simple-minded. Assuming he’s in Washington, however, the moon will only block 81% of the sun. That might not be enough. But the Secret Service could tell him he’s got a rally to attend in South Carolina (they like him down there) and arrange him to be outside at just the right time. It’s a long shot, but one can dream.

PS: Another Democratic Congresswoman, Jackie Speier, who represents the area south of San Francisco, has called for the president* to be removed because he is mentally unfit: “[He] is showing signs of erratic behavior and mental instability that place the country in grave danger. Time to invoke the 25th Amendment”.

Consciousness As Mental, As Physical

It’s been argued that a scientist who grew up in a black and white room and never saw the color red could learn everything there is to know about the physics of light and the physiology of the human body, including what happens in the brain when someone sees red, but not know what red looks like. Presumably, a blind scientist with the same training would be in the very same position. Likewise, a deaf scientist could know everything about the physics and physiology involved in hearing a violin but not really know what a violin sounds like. This is supposed to show that there is something in the universe beyond the reach of the physical sciences: the mysterious mental phenomenon of consciousness.

“Mental” is a word I haven’t used much (or at all) in writing about consciousness, yet consciousness is clearly a mental phenomenon if anything is. But what does it mean for a phenomenon to be “mental”?

The obvious answer, although it’s not very helpful, is that “mental” means “not physical”. But what does that mean?

An exchange of letters I referred to last month between the philosopher Thomas Nagel and a professor of bioengineering, Roy Black, tries to deal with the question. Prof. Black criticizes the idea that “nonphysical factors” are involved in consciousness:

As is frequently noted, the physical basis of life itself used to be just as mysterious as consciousness, and it’s now well explained by biochemistry and molecular biology, without nonphysical factors. So although science as we know it doesn’t explain the link between neurons and consciousness, why expect the link to be “nonphysical” rather than “novel physical”? What is a nonphysical factor, anyway? If the dark energy propelling the expansion of the universe, the strong force holding atomic nuclei together, etc., etc., are physical, do we really need anything more exotic?

… Lots of things in biology—like the development of an organism from an egg—seem impossible, until we stretch our imagination to conceive of simple precursors and mechanisms that could have been worked on by natural selection over billions of years. To quote one of [the philosopher Daniel Dennett’s] nice lines, “evolution is a process that depends on amplifying things that almost never happen.” We need to determine what “thing,” what activity of neurons beyond activating other neurons, was amplified to the point that consciousness arose. What would a precursor of “feeling like” be? That’s what we need to stretch our imaginations further to figure out.

Prof. Nagel responds, but his response is based on an assumption:

The difficulty is that conscious experience has an essentially subjective character—what it is like for its subject, from the inside—that purely physical processes do not share [how does he know this?]. Physical concepts describe the world as it is in itself, and not for any conscious subject….

I agree with Black that “we need to determine what ‘thing’, what activity of neurons beyond activating other neurons, was amplified to the point that consciousness arose.” But I believe this will require that we attribute to neurons, and perhaps to still more basic physical things and processes, some properties that in the right combination are capable of constituting subjects of experience like ourselves, to whom sunsets and chocolate and violins look and taste and sound as they do. These, if they are ever discovered, will not be physical properties, because physical properties, however sophisticated and complex, characterize only the order of the world extended in space and time, not how things appear from any particular point of view [again, how does he know this?].

Nagel’s assumption is that a purely physical process cannot have a subjective character (it cannot “feel like something”). It cannot be “how things appear” from a particular point of view. But if consciousness is a physical process, it does have a subjective character. In that case, how things feel or appear are indeed physical properties of a process that occurs in space and time (it happens inside your head when you’re conscious).

Here’s my take on the mental/physical distinction. Nobody knows what the universe contains at the most fundamental level (or if there is a most fundamental level). But suppose that quantum field theory is correct and, quoting Prof. David Tong of Cambridge University (who I wrote about earlier this year):

The best theories we have tell us that the fundamental building blocks of nature are not particles but something much more nebulous and abstract. The fundamental building blocks of nature are fluid-like substances which are spread throughout the entire universe and ripple in strange and interesting ways. That’s the fundamental reality in which we live. These fluid-like substances, we have a name for, we call them “fields”.

Furthermore, when the fields ripple or are agitated in certain ways, we get sub-atomic particles. An electron, for example, is a kind of ripple in the electron field.

So when I say that consciousness is a physical process, what I’m saying is that consciousness is at bottom constructed from one or more quantum-level fields – or whatever the fundamental building blocks of the universe are – that somehow interact with the quantum-level fields – or other building blocks – from which everything else in the universe is constructed. Maybe consciousness involves a kind of fundamental field that physicists can’t measure or detect yet. Maybe it involves a new kind of interaction between fundamental fields that physicists already know about.

But consciousness seems to be part of the natural world in the same way other physical phenomena are. And because it’s part of the natural world – not a kind of free-floating spiritual or supernatural substance or phenomenon – consciousness can represent other physical events and processes outside itself. Consciousness being part of the world is why we can be consciously aware of our bodies and the world around us.

“Mental”, therefore, refers to what happens in our minds, but at bottom mental phenomena are physical phenomena. Consciousness, like gravity, digestion and baseball, is one of the things that happens in the world. In other words, the “mental” is a subset of the “physical”. Or so it seems to me.

The Way Consciousness Is

Thinking about the United States plumbing the depths of kakistocracy (rule by the worst) is all well and good, but back to consciousness.

The human brain is the most complex object anyone has ever tried to understand. It might be the most complex object in the universe. We might never understand how it works. Robert Burton, a neurologist, writes about being surprised by a patient with a paranoid fear of the FBI that was apparently caused by a mutation in his brain:

Though I didn’t know it at the time, I had run headlong into the “hard problem of consciousness,” the enigma of how physical brain mechanisms create purely subjective mental states. In the subsequent 50 years, what was once fodder for neurologists’ late night speculations has mushroomed into the preeminent question in the philosophy of mind. As an intellectual challenge, there is no equal to wondering how subatomic particles, mindless cells, synapses, and neurotransmitters create the experience of red, the beauty of a sunset, the euphoria of lust, the transcendence of music, or in this case, intractable paranoia.

Neuroscientists have long known which general areas of the brain and their connections are necessary for the state of consciousness. By observing both the effects of localized and generalized brain insults such as anoxia [total lack of oxygen] and anesthesia, none of us seriously doubt that consciousness arises from discrete brain mechanisms. Because these mechanisms are consistent with general biological principles, it’s likely that, with further technical advances, we will uncover how the brain generates consciousness.

However, such knowledge doesn’t translate into an explanation for the what of consciousness—that state of awareness of one’s surroundings and self, the experience of one’s feelings and thoughts. Imagine a hypothetical where you could mix nine parts oxytocin, 17 parts serotonin, and 11 parts dopamine into a solution that would make 100 percent of people feel a sense of infatuation 100 percent of the time. Knowing the precise chemical trigger for the sensation of infatuation (the how) tells you little about the nature of the resulting feeling (the what).

But why should we expect that knowing what chemicals cause the feeling of infatuation would tell us anything about what infatuation feels like? Aren’t those two different questions?

Suppose, however, that we keep improving our techniques for studying the brain, as Burton suggests, and eventually figure out how certain kinds of brain activity become consciousness. It doesn’t seem impossible that one day (maybe 1,000 years in the future) that we will fully understand how “subatomic particles, mindless cells, synapses, and neurotransmitters” allow us to be conscious, just as well as we understand how lungs allow us to breathe (although lungs are a lot less complicated than brains). Suppose we discover how one kind of brain activity becomes a feeling of infatuation and another kind becomes a feeling of resentment. 

Burton implies that we would still be left with what he calls the “what” question, although it might be better to call it the “why” question. Why does our consciousness have the specific properties it does? Why does a note on a violin sound just the way it does? Why does red look like this and not like this or this? In the case of color, scientists might understand perfectly well the relationship between different wavelengths of light, the physiology of our eyes and nervous system, and the colors we see. They would understand that such and such conditions, structures and processes are correlated with seeing red and others are correlated with seeing blue. All of our “how does this happen?” questions would have been answered. So would it still make sense to ask why a particular kind of light looks the way it does or a particular feeling feels the way it does?

I’m not sure it would. Once we understood what leads to colors looking the way they do, or what makes feelings feel the way they do, any “why” questions might disappear. Once we understand the “how” of consciousness, maybe there won’t be anything more to figure out. If there are any neurologists or philosophers still asking “why”, the best answer will be “that’s just the way it is” or “stop asking questions and go to sleep”.

That wouldn’t necessarily be a bad thing. After all, in science, we sometimes arrive at what appear to be “brute” facts. Why is the speed of light in a vacuum 186,282 miles per second instead of 186,300 miles per second? We may never know. That’s just the way the universe works. No further explanation is available. If you have a problem with our speed of light, go live in another universe. If you don’t like the particular colors you see, keep your eyes closed. Or become a cat.

Next up on this subject, assuming I stay conscious: What does it mean to say consciousness is a physical phenomenon? It’s obviously a mental phenomenon, so how can it be a physical one too?

What We Have In Mind (Consciousness Again)

Last week, I suggested that consciousness is a type of brain activity, the kind that consists in having a phenomenal field that includes sights, sounds, pains and the internal monologue depicted by authors as the “stream of consciousness”.

I also recommended that we reserve the phrase “conscious of” for the most important things we’re conscious of, things like our everyday surroundings, our feelings and our thoughts, not consciousness itself. This approach would rule out questions like “Are you conscious of consciousness?” that to me seem misguided and misleading. I don’t think we’re conscious of consciousness, but rather conscious of other things.

To say that we’re conscious “of” other things is to say that the components of consciousness represent other things. Thus, some of the brain activity that is consciousness represents things outside our bodies (e.g. trees falling in the forest). Some of it represents things inside our bodies (e.g. heartburn). And some represents things that exist neither inside nor outside our bodies: abstract things like possibilities (e.g. sanity in Washington), fictional characters (Wonder Woman) and ideas (justice or the number twelve).

From an article about dreaming, which is usually considered a kind of consciousness:

One of the main functions of our brain is to constantly create a model of the world around us, a sort of virtual reality that helps us interact with our environment.

When we’re awake, that model is heavily influenced by what we are seeing and hearing and feeling. But during sleep, when there’s not much input from our senses, the brain’s model of the world is more likely to rely on internal information, like memories or expectations.

I’d add that the model is also a model of the world within us and the abstract world of memory, intention and imagination. But thinking of the model our brains create as “a sort of virtual reality” is what I have in mind (that’s a pun). It’s the “sort” of virtual reality that isn’t virtual, however. Patterns of neural activation in the brain (what the model is made of) are quite real. And it’s a model or representation of other things that are quite real too, like falling trees and sprained ankles.

One of the things that makes our conscious model interesting is that it includes events and processes that are strictly or primarily mental, like having a premonition. I don’t know if such things are representations of unconscious mental events and processes. Maybe they aren’t representations at all; maybe they’re patterns of neural activation that don’t refer to or represent anything else. But the evidence suggests that we all have a lot of unconscious brain activity that plays a very large role in what we think and how we feel.

So it would be consistent with the view I’m trying to explain that when you have something like a premonition, what you’re conscious of is a representation of the underlying brain activity (the unconscious premonition processing), as well as any related events in your body (like chills).

To sum up, the position I’ve arrived at seems to be a strange, possibly ridiculous mixture of ideas associated with two great philosophers who are generally seen as opponents: the idealist George Berkeley and the materialist Thomas Hobbes.

Berkeley (1685-1753) argued that nothing exists independently of minds: “To be is to be perceived (or to perceive)”. A person is an immaterial mind or soul. The physical world (the Earth, for example) doesn’t exist independently of our minds. Fortunately, our individual minds are able to get along because God (a kind of super-mind) synchronizes our perceptions. He makes sure that when I perceive a red apple (in my mind), you do too.

Hobbes (1588-1679) argued that nothing exists except physical stuff. We human beings, including our minds, are material things. Even God may be a kind of material being. When I see a red apple, and you see a red apple, therefore, it’s because there’s an apple out there and it’s red. That’s the whole story. 

Where I’ve ended up is to agree with Berkeley that our consciousness has the various elements in it that he called “perceptions” and “ideas”. But I agree with Hobbes that consciousness is a physical phenomenon, a very cool physical phenomenon, but a physical one just the same. And the reason my perceptions usually line up with yours so nicely is because our perceptions represent the same physical world, albeit observed from our individual perspectives. 

I Did the Reading, So Now I’m Sharing

I read too many articles on the internet about politics. Instead of having one subscription to a high-quality newspaper that used to land on our driveway every morning, I now subscribe to three quality newspapers that I read online. I also visit a number of websites that offer interesting political news and commentary. All you need to give them is your time (although that, of course, is more precious than your money).

Ordinarily, I wouldn’t spend so much time reading about politics, but I want to understand what the hell is going on, i.e., why America is so screwed up. And after I read something, I sometimes feel the need to share. This reading and sharing might be a big waste of time, but it feels like something I should do.  

This explains why I read three long-ish articles in the past few days that I’m now going to mention and very briefly describe. Then I’m going to share a funny video. And then I’m going to share a little good news for a change.

The first article I read was “Donald Trump and the Rise of Tribal Epistemology”. The title isn’t quite accurate, because epistemology is the philosophical theory or study of knowledge. The title should really be something like “Trump and the Rise of Right-Wing Propaganda as a Source of Supposed News for Millions of Americans and the Ill Effects Thereof”. Another title might be “Here’s Why Our Country Is So Screwed Up: Many Americans Don’t Trust the Only Institutions We Have That Do a Fairly Decent Job of Describing Reality, and Is There Anything We Can Do About It?”. I recommend reading the whole thing, which isn’t really seven million words long, despite what the author says.

A link in that article led me to a 2016, pre-election article called “The Rise of American Authoritarianism”. It’s about people with authoritarian personalities, and how they aren’t necessarily bigots or stupid, but how they tend to be afraid of strangers and change, and when they’re especially afraid, they look for “strong” leaders who will protect them by building walls, putting people in jail and blowing things up. There are more of these authoritarians than you might expect and they’re the strongest supporters of the current President, for obvious reasons (“I alone can fix it”).

An interesting point is that the social scientists cited in the article don’t identify people with authoritarian tendencies by asking them about politics. They ask them about child-rearing, posing questions like these:

  • Please tell me which one you think is more important for a child to have: independence or respect for elders?
  • Please tell me which one you think is more important for a child to have: obedience or self-reliance?
  • Please tell me which one you think is more important for a child to have: to be considerate or to be well-behaved?
  • Please tell me which one you think is more important for a child to have: curiosity or good manners?

Authoritarians tend to answer these questions differently than the rest of us. Furthermore, they supposedly tell the truth when asked about raising children, which they might not do if asked about politics.

Another point made in the article is that many people have authoritarian tendencies, but those tendencies only come into play when these potential authoritarians are sufficiently scared, and sufficiently scared by people whom they think are dangerous in some way, either dangerous to their physical persons or to their preferred way of life. 

The importance of the fear factor leads to the third article, “How Fox News Changed American Media and Political Dynamics”. I confess I didn’t read the whole thing, because it was too depressing. It was written two years ago by a former Republican and is mostly historical. It describes the undoing of the Federal Communications Commission’s Fairness Doctrine, the rise of right-wing talk radio and the amazing success of Fox News, the result being that your authoritarian cousin and your potentially authoritarian plumber are convinced that liberals, scientists, the “mainstream media” and other lowlifes are out to destroy America. That makes your cousin and your plumber very angry and/or very, very afraid. 

So here’s the funny video: Randy Rainbow singing “Covfefe: The Broadway Medley”! If nothing else, watching it will mean that, for four glorious minutes, you won’t be reading about politics on the internet. 

I’ve watched this video many times, because, aside from the pleasure of watching and listening to Mr. Rainbow, and hearing those wonderful melodies again, if you do anything for four minutes, over and over again, it does add up. 

Lastly, the good news:  “Nevada Is Considering a Revolutionary Healthcare Experiment”. The Nevada legislature has passed a bill that would allow anyone in the state who doesn’t have health insurance to buy in to the state’s Medicaid program. Details need to be worked out and the Governor might not sign the bill, but it’s an encouraging sign that America might turn the corner one day.

“Covfefe, I just met a girl named Covfefe…”

Glowing Mouse Heads and How Our Brains Get Washed

Herewith, edited excerpts from a Washington Post article of special interest to people with brains:

The lymph network carries immune cells throughout the body and removes waste and toxins. It was accepted wisdom for more than 300 years that the network didn’t extend into the brain. 

Three years ago, scientists trying to develop a more precise map of the lymphatic system used genetically-modified mice whose lymphatic vessels glowed when illuminated by a particular wavelength of light. The mice had been given a gene from a species of glowing jellyfish.

Seeing that the mouse’s heads glowed, the researchers realized that the lymphatic vessels extended into the brain after all. This was surprising, to say the least: In the 21st century, major findings involving basic human anatomy are rare. “These days, you don’t make discoveries like this”, one of the scientists said.

Since the lymph network also extends into human brains, this discovery has major implications for a wide variety of brain diseases, including Alzheimer’s, multiple sclerosis, stroke and traumatic brain injury.

Researchers have identified two networks: the vessels that lead into and surround the brain, and those within the brain itself. The latter is called the “glymphatic” system for the glia, the kind of neuron that makes up the lymphatic vessels in the brain. The glymphatic vessels carry cerebrospinal fluid and immune cells into the brain and remove cellular trash from it.

There is evidence that when the systems malfunction, the brain can become clogged with toxins and suffused with inflammatory immune cells. Over decades, this process may play a key role in Alzheimer’s disease, Huntington’s disease, Parkinson’s disease and other degenerative illnesses. 

“This is a revolutionary finding,” one researcher says. “This system plays a huge role in the health of the brain.” She describes the glymphatic system as like a dishwasher for the brain. “The brain is very active and so it produces a lot of junk that needs to be cleaned out.”

In hindsight, the system should have been noticed long ago. When the skull and head are dissected, the vessels are visible to the naked eye. But no one bothered to really look.

The vessels have also been implicated in autoimmune disease, such as multiple sclerosis. Researchers knew that the immune system has limited access to the brain. But at the same time, the immune system kept tabs on the brain’s status; no one knew exactly how. Some researchers theorize that the glymphatic system could be the conduit. In diseases like multiple sclerosis — where the body’s immune system attacks certain brain cells — the communication may go awry.

Recently, Harvard University researchers reported that glymphatic flow is significantly decreased in the period just before a migraine. The intense pain in these headaches is caused largely by inflamed nerves in the tissue that surrounds the brain. The authors of the study theorize that faulty clearance of molecular waste from the brain could trigger inflammation in these pain fibers.

One key to glymphatic performance seems to be sleep. At least in mice, the system processes twice as much fluid during sleep as it does during wakefulness. It’s possible that sleep dysfunction may contribute to Alzheimer’s and perhaps other brain illnesses: “You only clean your brain when you’re sleeping. This is probably an important reason that we sleep. You need time off from consciousness to do the housekeeping”.

It also appears that sleep position is crucial. In an upright position — someone who is sitting or standing — waste is removed much less efficiently. Sleeping on your stomach is also not very effective; sleeping on your back is somewhat better, while lying on your side appears to produce the best results. The reason for these differences might be related to the mechanical engineering of the lymphatic vessels and valves; the healthiest approach may be to move periodically while you sleep.

Sleep is probably not the only way to improve glymphatic flow. Omega-3 fatty acids and deep breathing may also improve glymphatic functioning. 

Not being a scientist, I can’t evaluate these studies, but it makes sense that brains produce a lot of junk that needs to be cleaned out. (And you didn’t think the President would come up in this post.)