The shadow knows

One of the most terrifying sleep-related phenomena is sleep paralysis.

I say this only from hearing about the experiences of others; I have never had it happen to me.  But the people I've talked to who have had episodes of sleep paralysis relate being wide awake and conscious, but unable to move -- often along with some odd sensory experiences -- such as feelings of being watched or having someone in the room; hissing, humming, or sizzling noises; a tingling in the extremities that feels like a mild electric shock; a feeling of being suffocated; and (understandably) the emotions of fear and panic.

The reason all of this comes up is an article that appeared over at the site Mysterious Universe about "Shadow People."  The piece was by Nick Redfern, whose name should be familiar to anyone who is an aficionado of cryptozoology; Redfern has been involved in a number of investigations of the paranormal, and is the author of books such as The Roswell UFO Conspiracy, Shapeshifters: Morphing Monsters and Changing Cryptids, The Real Men in Black, The New World Order Book, and a variety of other titles I encourage you to peruse.

So Redfern has a pretty obvious bias, here, which is why I was already primed to view his piece on the Shadow People with a bit of a jaundiced eye.  Let me let him speak for himself, though.  Redfern tells us that there are these entities that we should all be on the lookout for, and then tells us the following:

Jason Offutt is an expert on the Shadow People, and the author of a 2009 book on the subject titled Darkness Walks: The Shadow People Among Us.  He says there are eight different kinds of Shadow People – at least, they are the ones we know about.  He labels them as Benign Shadows, Shadows of Terror, Red-Eyed Shadows, Noisy Shadows, Angry Hooded Shadows, Shadows that Attack, Shadow Cats, and the Hat Man.

Shadow Cats?  Why only cats?  Cats, in my experience, are already conceited enough that they don't need another feather in their caps.  Of course, the positive side is that Shadow Cats wouldn't be very threatening. The cats I've owned specialized in two behaviors: Sitting Around Looking Bored, and Moving Closer To Where We Are So We'll Appreciate How Bored They Are.  If their Shadow versions are no more motivated, it's hard to see why you'd even care they were around, since Shadow Cats presumably don't eat, drink, or use a litter box.  They'd kind of be a low-impact paranormal home décor item.

On the other hand, I'm just as glad there are no Shadow Dogs, because then we'd have yet another source of the really obnoxious noise that dogs make when they are conducting intimate personal hygiene, a sound my wife calls "glopping."  Our three dogs glop enough, there's no need for additional glopping from the spirit world.

But then there's "Hat Man."  On first glance, that seemed fairly non-threatening, but Redfern tells us that Hat Man is the scariest one on the list:

I sat and listened at my table [at a conference, speaking to an attendee] as he told me how, back in July of this year, he had three experiences with the Hat Man – and which were pretty much all identical – and which were very familiar to me.  He woke up in the early hours of the morning to a horrific vision: the outside wall of his bedroom was displaying a terrifying image of a large city on fire, with significant portions of it in ruins.  It was none other than Chicago.  The sky was dark and millions were dead.  Circling high above what was left of the city was a large, human-like entity with huge wings.  And stood [sic] next to the guy, as he watched this apocalyptic scenario unravel from his bed, was the Hat Man, his old-style fedora hat positioned firmly on his head.  The doomsday-like picture lasted for a minute or two, making it clear to the witness that a Third World War had begun.  On two more occasions in the same month, a near-identical situation played out.  It’s hardly surprising that the man was still concerned by all this when we chatted at the weekend.

So he talked to some other people, and more than one person mentioned seeing Hat Man, and always associated with images of doom and destruction.  Toward the end, he mentions the fact that one of the people who'd seen Hat Man suffered from sleep paralysis... which kind of made me go, "Aha."

In a paper by Walther and Schulz back in 2004 entitled, "Recurrent Isolated Sleep Paralysis: Polysomnographic and Clinical Findings," it was found that people who suffered from sleep paralysis showed abnormal patterns of REM and non-REM sleep, and (most interestingly) fragmentation of REM.  REM, you probably know, is associated with dreaming; suppressing or disturbing REM causes a whole host of problems, up to and including hallucination.  Another paper -- Cheyne, Rueffer, and Newby-Clark, in 1999, "Hypnagogic and Hypnopompic Hallucinations during Sleep Paralysis: Neurological and Cultural Construction of the Night-Mare" -- has another interesting clue, which is that during sleep paralysis, cholinergic neurons (the neural bundles that promote wakefulness and REM) are hyperactive, whereas the serotonergic neurons (ones that initiate relaxation and a sense of well-being) are inhibited.  This implies that the mind becomes wakeful, but emotionally uneasy, before the brain-body connection comes back online.

[Image is in the Public Domain]

The problem here is that if you're in sleep paralysis, or the related phenomenon of hypnagogic experiences (dreams in light sleep), what you are perceiving is not reflective of reality.  So as creepy as Shadow People are -- not to mention "Hat Man" -- I'm pretty certain that what we've got here is a visual hallucination experienced during a dream state.

Not sure about the Shadow Cats, though.  I still don't see how that'd work.  Given my luck at trying to get cats comply with simple rules such as "Stay The Hell Off The Kitchen Counter," my guess is that even feline hallucinations wouldn't want to cooperate.  If you expected them to show up and scare some poor dude who was just trying to get a good night's sleep, they'd probably balk because it wasn't their idea.  Shadow Dogs, on the other hand, would be happy to climb on the sleeping dude's bed and glop right next to his ear.  They're just helpful that way.

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Balm of hurt minds

The main character of Haruki Murakami's brilliant and terrifying short story "Sleep" is a perfectly normal middle-class woman living in Tokyo.  Her husband is a dentist, and they've got a lively, cheerful five-year-old son.  Everything about her life is so ordinary that it's hard even to describe.

Then, in one instant, all that changes.

One night, she awakens -- or thinks she has -- to a terrifying vision that even afterward, she's not certain was real or a hallucination during sleep paralysis.  A dark shape is huddled by the foot of her bed, and unfolds itself to reveal the figure of an elderly man, dressed in black, staring at her with an undisguised malevolence.  She attempts to scream, and can't.  After a moment, she forces herself to close her eyes, and when she opens them, the man is gone.  She's drenched with sweat, so she gets up, showers, pours herself a brandy, and waits for morning.

But after that moment, she is completely unable to go to sleep.  Ever.

The remainder of the story could be a teaching text in a fiction writing course lesson about how to create a believable Unreliable Narrator.  She returns to her ordinary life, but everything starts seeming... off.  Some senses are amplified, others dulled into nonexistence.  Everyday objects appear surreal, as if they've changed subtly, but she can't quite tell how.  One evening, she watches her husband as he's sleeping, and realizes that his face suddenly looks ugly to her.  She takes to going out driving at night (once her husband and son are asleep) and meets people who may or may not be real.  Her progressive slide into insanity reaches its apogee in the wee hours of one night, after seventeen days with no sleep, when she drives farther than she has ever driven, and ends up in an empty parking lot overlooking the ocean.  Dark figures raise themselves on either side of her little car, grab it by the handles, and begin to rock it back and forth, harder and harder.  She's thrown around by the motion, slamming against the door and steering wheel, and her last panicked thought is, "It's going to flip over, and there's nothing I can do to stop it."

An apt, if disturbing, summation of what is happening to her mind.

Sleep is an absolutely critical part of human health, but even after decades of research, it is unclear why.  Just about every animal studied sleeps, and many of them seem to dream -- or at least undergo REM sleep -- the same as we do.  (I know my dogs do; both of them bark and twitch in their sleep, and our sweet, gentle little dog Rosie sometimes growls as if she was the biggest meanest Rottweiler on the planet.)

Now, a team at the Binzhou Medical University's Shandong Technology Innovation Center has found one reason why sleep is so critical.  Sleep-deprived mice stop producing a protein called pleiotrophin, which apparently has a protective effect on the cells of the hippocampus.  Reduced pleiotrophin levels lead to cell death -- impairing both memory and spatial awareness.  Pleiotrophin decline has also been implicated in neurodegenerative diseases like Alzheimer's.

[Image licensed under the Creative Commons Sasha Kargaltsev, Sleeping (10765632993), CC BY 2.0]

What's unclear, though, is what direction the causation points.  Does the decline in pleiotrophin from sleeplessness cause the neurodegeneration, or does the neurodegeneration lead to insomnia and a drop in pleiotrophin levels?  The current research suggests the former, as the mice in the study had been genetically engineered to experience sleep disturbances, and the pleiotrophin loss seems to have followed as a consequence of the sleep deprivation.  Then, the question is, if pleiotrophin decline does trigger neurodegeneration, could the damage from Alzheimer's be prevented by increasing the production of the protein?

Uncertain at this point, but it's intriguing to find one piece of a puzzle that has intrigued us for centuries.  It seems fitting to end this musing on the power of sleep with the famous quote from Macbeth:

Methought I heard a voice cry ‘Sleep no more!
Macbeth does murder sleep,’ the innocent sleep,
Sleep that knits up the ravell’d sleave of care,
The death of each day’s life, sore labour’s bath,
Balm of hurt minds, great nature’s second course,
Chief nourisher in life’s feast.

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Dream weavers

In Ursula LeGuin's amazing and disturbing novel The Lathe of Heaven, a very ordinary guy finds that he has a completely unordinary ability.

When he dreams, he wakes up and finds that whatever he dreamed has become reality.

George Orr, the protagonist, is terrified by this, as you might imagine.  It's not like he can control what he dreams; he isn't able to program himself to dream something pleasant in order to find he has it when he wakes.  No, it's more sinister than that.  Consider the bizarre, confusing, often frightening content of most of our dreams -- dreams that prompt you to say the next morning, "Where the hell did that come from?"

That is what makes up George's reality.

The worst part is that George is the only one who knows it's happening.  When his dream content alters reality, it alters everything -- including the memories -- of the people he knows.  When he wakes up and finds that the cityscape has changed and that some people he knew are gone, replaced with others he has never seen before, everyone else's memories changed as well.  George wakes to find he has a girlfriend, but she doesn't think it's sudden and weird; being George's girlfriend is what she remembers.

Only George sees that this is just the latest version of a constantly shifting reality.

So when he tries to explain to people what he can do, and (if possible) find a way to stop it, no one believes him.  No one... except a ruthless and ambitious psychiatrist who realizes that if he can figure out how to manipulate George's dreams, he can fashion a world to his own desires, using George as a tool to create the reality he wants.

LeGuin's terrifying vision of what happens when grasping amorality meets a naïve but useful skill is turning out not to be far from being realized.  George Orr's paranormal ability is the stuff of fiction, of course; but the capacity for influencing our dreams is not.

Nor, apparently, is the potential for using our dreams as a conduit for suggestions that might alter our behavior -- with or without our permission, possibly with or without our knowledge.

[Image licensed under the Creative Commons stephentrepreneur, Hurtle Square dreams, CC BY-SA 2.0]

I found out yesterday from a friend and loyal reader of Skeptophilia that there is a cohort of powerful corporations who have teamed up to see if there's a way to insert advertising content into our dreams.  Xbox, Coors, Microsoft, and Burger King, among others, have been experimenting on volunteers to see if they can introduce targeted advertising while we're asleep, and (especially) while we're at the neurologically hyperactive REM (rapid eye movement) stage of sleep, in order to induce people to alter their behavior -- i.e., purchase the product in question -- once they wake up.  They've had some success; a test by Coors found that sixty percent of the volunteers were susceptible to having these kinds of product-based suggestions influence their dream content.

Forty sleep and dream researchers are now pushing back, and have drafted a document calling for regulation of what the corporate researchers are calling "dream incubation."  "It is easy to envision a world in which smart speakers—forty million Americans currently have them in their bedrooms—become instruments of passive, unconscious overnight advertising, with or without our permission," the authors state.

My fear is that the profit motive will outweigh any reluctance people might have toward having their dreams infiltrated by corporate content.  If cellular service providers were willing to give users a discount on their monthly fees, provided they agreed to allow themselves to be exposed to ads during the nighttime hours, how many people would say, "Sure, okay, go for it"?  I know for myself, I'm often willing to tolerate ads on games and video streaming services rather than paying extra to go ad-free.  I'd like to think that I'm able to tune out the ads sufficiently that they're not influencing my behavior, but what would happen if I'm exposed to them for all eight to ten hours that I'm sleeping every night?

Not all scientists are concerned about the technique's efficacy, however.  "Of course you can play ads to someone as they are sleeping, but as far as having much effect, there is little evidence," said Deirdre Barrett, a dream researcher at Harvard University.  "Dream incubation doesn’t seem very cost effective compared with traditional advertising campaigns."

Even if it doesn't have the manipulative capability the corporations are hoping, the idea still scares the hell out of me.  When every moment of our days and nights become just another opportunity for monetization, where will it all stop?   "I am not overly concerned, just as I am not concerned that people can be hypnotized against their will," said University of Montreal dream researcher Tore Nielsen.  "If it does indeed happen and no regulatory actions are taken to prevent it, then I think we will be well on our way to a Big Brother state … [and] whether or not our dreams can be modified would likely be the least of our worries."

Which is it exactly.  As I've pointed out before, my main concern is about the increasing control corporate interests have over everything.  And here in the United States, the problem is that the people who could potentially pass legislation to limit what the corporations can get away with are being funded largely by corporate donors, so they're not anxious to put the brakes on and see that flow of cash dry up suddenly.  It's a catch-22 that would require the government to police its own behavior for no other reason than simple morality and ethics.

And you can guess how successful that is likely to be.

I'm hoping that at least someone is listening, though.  I tend to agree with Nielsen; I don't think our dream content will be as easily manipulable, or as behavior-altering, as the corporations hope.  But what I'm more worried about is that once we refuse to delineate a hard line around our personal lives, and say to them, "Here, and no further," we've opened ourselves up to there being no part of our personal space that isn't considered a target for monetization.

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In 1924, a young man named Werner Heisenberg spent some time on a treeless island in the North Sea called Helgoland, getting away from distractions so he could try to put together recently-collected (and bizarre) data from the realm of the very small in a way that made sense.

What he came up with overturned just about everything we thought we understood about how the universe works.

Prior to Heisenberg, and his colleagues Erwin Schrödinger and Niels Bohr, most people saw subatomic phenomena as being scaled-down versions of familiar objects; the nucleus like a little hard lump, electrons like planets orbiting the Sun, light like waves in a pond.  Heisenberg found that the reality is far stranger and less intuitive than anyone dreamed, so much so that even Einstein called their theories "spooky action at a distance."  But quantum theory has become one of the most intensively tested models science has ever developed, and thus far it has passed every rigorous experiment with flying colors, providing verifiable measurements to a seemingly arbitrary level of precision.

As bizarre as its conclusions seem, the picture of the submicroscopic world the quantum theory gives us appears to be completely accurate.

In Helgoland: Making Sense of the Quantum Revolution, brilliant physicist and writer Carlo Rovelli describes how these discoveries were made -- and in his usual lucid and articulate style, gives us a view of some of the most groundbreaking discoveries ever made.  If you're curious about quantum physics but a little put off by the complexity, check out Rovelli's book, which sketches out for the layperson the weird and counterintuitive framework that Heisenberg and others discovered.  It's delightfully mind-blowing.

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Dream weaving

In the Star Trek: The Next Generation episode "Night Terrors," the ship gets trapped in a phenomenon called "Tyken's Rift," one of the myriad hand-waving scientific phenomena they came up with as plot devices.  It's some sort of rip in the space-time continuum -- I swear, given how often it rips in that show, you'd swear the space-time continuum was made of wet Kleenex -- and the upshot is that it causes a weird result for the crew.  They lose their ability to drop into REM sleep, so they're prevented from dreaming.

And it causes them to start hallucinating, and eventually, to go violently insane.  It'd happened to another ship, whose crew ended up killing each other.  This led to one of the single creepiest images the show ever came up with, while Dr. Crusher is in the morgue doing post-mortems on the dead crew members -- and is beginning to hallucinate herself.

There are a number of aspects of the episode that are pretty silly, but this one scene works brilliantly, mainly because it highlights exactly how surreal and terrifying dreams can be.  While you're inside them, they seem absolutely real.  In the last couple of years, I've had a number of dreams of being attacked by an animal -- odd in and of itself, because I always have gotten along with animals.  Dogs, in fact, like me a great deal better than people do.  But each time, I'm minding my own business, and some animal charges me, causing me to wake up, and more than once, to shout out, waking my poor long-suffering wife.

Why do I dream this stuff?  In fact, why does anyone dream what they do?  That's an interesting, and not an easy, question.  It brings to mind a topic that came periodically in my biology classes, involving the difference between proximal and ultimate causes.  In a proximal sense, we know that dreaming is caused by an activation of the visual and auditory cortices and a reduction in activity of the prefrontal cortex during REM sleep, triggering us to imagine vivid images and sounds while simultaneously shutting off one of the primary "reality filters" we have (explaining why dreams can seem to make sense while we're in them, and completely batshit insane once we wake up).

But when students asked "why do we dream?" that's not usually what they meant.  They were looking for a deeper, ultimate cause -- what purpose does it serve?  What is the overarching reason for dreaming?  And there, we go into what is largely uncharted territory.  Science, it turns out, is not so good at teleology -- the analysis of ultimate causes, explanations that don't just look at the mechanism, but the purpose or driver behind them.

This is why I was a little dubious about a paper by Erik Hoel of Tufts University that appeared in the journal Patterns last week.  Entitled, "The Overfitted Brain: Dreams Evolved to Assist Generalization," Hoel claims that his study of artificial intelligence/deep neural networks suggests that the purpose of dreams is to help us generalize what we've learned -- that our ordinary experience gives us limited ability to develop flexibility (i.e., we usually are confronted with the same stuff over and over again), so dreams interject a hefty dose of pure weirdness to help us learn to deal with the unexpected.

Hoel writes:

Understanding of the evolved biological function of sleep has advanced considerably in the past decade.  However, no equivalent understanding of dreams has emerged.  Contemporary neuroscientific theories often view dreams as epiphenomena, and many of the proposals for their biological function are contradicted by the phenomenology of dreams themselves.  Now, the recent advent of deep neural networks (DNNs) has finally provided the novel conceptual framework within which to understand the evolved function of dreams.  Notably, all DNNs face the issue of overfitting as they learn, which is when performance on one dataset increases but the network's performance fails to generalize (often measured by the divergence of performance on training versus testing datasets).  This ubiquitous problem in DNNs is often solved by modelers via “noise injections” in the form of noisy or corrupted inputs.  The goal of this paper is to argue that the brain faces a similar challenge of overfitting and that nightly dreams evolved to combat the brain's overfitting during its daily learning.  That is, dreams are a biological mechanism for increasing generalizability via the creation of corrupted sensory inputs from stochastic activity across the hierarchy of neural structures.  Sleep loss, specifically dream loss, leads to an overfitted brain that can still memorize and learn but fails to generalize appropriately. 

It's an interesting idea.  And I have to admit that the dream I had a few nights ago, wherein a horse jumped a fence and charged straight at me, hooves flying and teeth bared, is pretty fucking stochastic.  I am, however, a bit wary of any claim of the form "X is a widespread phenomenon, and it happens because of Y."  Complex phenomena -- which dreaming certainly is, given people's varied experience of it -- seldom have only a single proximal cause, much less a single ultimate cause.  And as I said, ultimate causes are notoriously tricky to identify anyhow.  Even some simpler questions to frame than dreaming -- such as why humans have upright posture -- have yet to be settled.  (Some suggestions are that it was to give us farther sight distance in the grasslands where we evolved, to leave our hands free to manipulate tools, that it made it easier to wade in order to gather aquatic organisms like shellfish for food, that it improved walking and running endurance, that it allowed our ancestors to reach fruit in trees more easily, that it made it easier for mothers to hold their infants while moving from place to place...  In point of fact, it could be any of these, all of these, or various other advantages not on the list, and it would be extremely difficult to discern which is correct.)

All of which is not meant to criticize Hoel's hypothesis specifically, because it's pretty intriguing.  I'm just always hesitant to jump to an appealing explanation just because "it sounds like it makes sense."  Reality is awfully complex, and explanations can be hard to come by.

But whatever the reason is, I'd sure like it if I could stop dreaming about being attacked by vicious animals.  My wife would like it, too.  Being awakened in the middle of the night because your husband is dreaming he's being attacked by a raging wombat kind of gets old after a while.

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Too many people think of chemistry as being arcane and difficult formulas and laws and symbols, and lose sight of the amazing reality it describes.  My younger son, who is the master glassblower for the chemistry department at the University of Houston, was telling me about what he's learned about the chemistry of glass -- why it it's transparent, why different formulations have different properties, what causes glass to have the colors it does, or no color at all -- and I was astonished at not only the complexity, but how incredibly cool it is.

The world is filled with such coolness, and it's kind of sad how little we usually notice it.  Colors and shapes and patterns abound, and while some of them are still mysterious, there are others that can be explained in terms of the behavior of the constituent atoms and molecules.  This is the topic of the phenomenal new book The Beauty of Chemistry: Art, Wonder, and Science by Philip Ball and photographers Wenting Zhu and Yan Liang, which looks at the chemistry of the familiar, and illustrates the science with photographs of astonishing beauty.

Whether you're an aficionado of science or simply someone who is curious about the world around you, The Beauty of Chemistry is a book you will find fascinating.  You'll learn a bit about the chemistry of everything from snowflakes to champagne -- and be entranced by the sheer beauty of the ordinary.

[Note: if you purchase this book from the image/link below, part of the proceeds goes to support Skeptophilia!]

Follow the compass needle

I have to resist the temptation of scoffing too quickly, but sometimes it turns out to be justified.

This comes up because of an article from Body Ecology called "Could the Direction You Sleep In Improve Your Health and Well-Being?" that a loyal reader of Skeptophilia sent me yesterday.  The contention of the article is that should never sleep with your head pointing north or west; east or south is best.  Fail to follow this advice, and you're seriously risking getting some horrible disease.  It then goes into some "Eastern medicine" goofiness and stuff about "feng shui" that has no scientific validity whatsoever.

The article states, cheerfully, "[S]cience and eastern medicine both agree" that sleep direction makes a difference, a claim that made me snort derisively.

But one thing caught my eye, which is that the article said there's been a study -- a real study, not some hand-waving mystical nonsense -- that showed people who sleep oriented north/south have shorter periods of REM (rapid-eye movement) sleep than people oriented east/west.  There was no link provided, nor even a mention of where or by whom the study had been conducted, but I thought I'd give the author the benefit of the doubt and try to track it down.

[Image licensed under the Creative Commons Evgeniy Isaev from Moscow, Russia, Sleeping man. (7174597014), CC BY 2.0]

After some digging, I found the paper they were referencing.  It was from way back in 1987, and was written by three scientists in Germany, one at the Max Planck Institute, and the other two at the University of Munich.  Entitled, "Dependence of a Sleeping Parameter from the N-S or E-W Sleeping Direction," wherein eight male subjects were subjected to EEGs for eight nights each, alternating nights while sleeping oriented north/south with nights oriented east/west.  The authors write:

The only significant difference occurred in REM latency which was 5.5 min shorter in E-W direction (p< 0.02).  Other sleep parameters which could be interpreted as stress parameters (sleep latency, intermittent awakenings, percentage of stage 1, stageshifts, movement times) were not different between the two positions.  The same goes for the other parameters.

So the Body Ecology got the facts wrong; the north/south sleepers didn't REM less, they had longer REM latency -- the time from the onset of sleep to the first episode of REM.  And that was only by five and a half minutes.  In fact, there was a great deal more difference between the REM latency of all the subjects for the first four versus the second four nights, regardless of what direction they were oriented -- a difference of 22 minutes.

Nevertheless, the authors conclude hopefully:

The adaption effects are balanced out by the fact that two paired subjects slept always in different directions. The fact that among the sleep parameters REM latency is affected by the position of the bed... seems to support our interpretation because mainly REM latency reacts to external influences. Therefore the most probable interpretation of our observation is the assumption that the geomagnetic field influences humans differently depending on their positions relative to the field direction.

I'm no statistician, but it seems to me that eight subjects studied for eight nights, resulting in a difference in REM latency of five and a half minutes and no other significant changes, is pretty weak evidence that there's anything to see here.  It's also significant that the article was published in 1987 -- and I couldn't find a single other study of the claim since that time.

The piece in Body Ecology also mentions a second study (once again, no link) claiming that other mammal species respond to the Earth's magnetic field.  That's not so far-fetched; it's known that many bird species exhibit magnetotaxis, which is orientation based on an internal compass.  (This was discovered by a study way back in 1971 done right here at Cornell University.)  But the mammals claim was new to me, and appears to come from a 2008 study at the University of Duisberg-Essen (Germany) claiming that satellite images of herds of deer and cattle showed that they preferentially oriented their bodies north/south.  The authors don't bother to speculate as to why they would do this, and claim to have controlled for such factors as prevailing wind direction and the angle of the sun.  But a 2011 study tried to replicate the results and failed -- there was no preferred orientation.  Cattle and deer did pretty much what you'd expect they'd do, which is stand around eating stuff facing any way that happens to be convenient.

Of course, weirder things have been claimed.  A 2013 paper in Frontiers of Zoology said that a two-year study of dogs showed that they preferred to poop while aligned north/south.  Which raises a question: who even thought of looking into this idea?  I mean, thinking outside the box is one thing, but this is a bizarre question to ask.  Maybe the scientists, like me, tire of having their dogs turn in circles 832 times before relieving themselves, and wanted to know why they were doing it.

Unsurprisingly, this study was questioned, too, most rigorously by Duncan Forgan over at Research the Headlines, who had the following to say:

On the other hand, the dog’s magnetoception (if it possesses it) does not appear to be particularly effective in general.  When the researchers pooled all the data (calm and not-calm magnetic fields), they saw no evidence of alignment at all, meaning that dogs can only rely on this sense if the magnetic field behaves itself, which only happened during around a third of the researcher’s observations. 

It also means that if you own a dog, you are probably unlikely to notice any alignment, unless you’re willing to only note your pup’s pooping practices when you’ve previously measured a stable magnetic field.

An experiment which, frankly, I am not nearly interested enough to carry out.

Anyhow.  It looks like my scornful reaction to the original article is more or less warranted, and any evidence that humans respond behaviorally (or any other way) to the Earth's magnetic field is questionable at best.  If it floats your boat to turn your bed so your head is facing east, knock yourself out, but I'm guessing any difference you notice will be because you expected there to be a change -- i.e., the placebo effect.

For what it's worth, though, I sleep with my head pointing north, and I'm a notorious insomniac.  It's only one data point, but make of it what you will.

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This week's Skeptophilia book recommendation is a classic: the late Oliver Sacks's The Man Who Mistook His Wife for a Hat.  It's required reading for anyone who is interested in the inner workings of the human mind, and highlights how fragile our perceptual apparatus is -- and how even minor changes in our nervous systems can result in our interacting with the world in what appear from the outside to be completely bizarre ways.  Broken up into short vignettes about actual patients Sacks worked with, it's a quick and completely fascinating read.

Living the dream

Last night I dreamed I was in my classroom.  It wasn't my real classroom, however -- it looked like a 19th century lecture hall.  Wooden desks, old cabinets containing jars with ground-glass stoppers, various pieces of equipment of uncertain purpose, some of which looked like (and may in fact have been) torture equipment.  My son lived in an apartment above my classroom, with his wife, which is especially curious because he's not married.  I was teaching a lesson on the reproductive systems of monkeys, but my students weren't listening.  Also, my son kept coming out on the balcony (of course there was a balcony) and interrupting my lecture to ask me questions about the rules of rugby.

After that, it got a little weird.

Neuroscientists have been trying to figure out the physiological function of dreams for years.  The contention is that they must be doing something important, because they're so ubiquitous.  Judging from my own dogs, even other species dream.  Sometimes they have exciting dreams, with muted little barks and twitching paws, often ending in a growl and a shake of the head, as if they're killing some poor defenseless prey; other times they have placid dreams, eliciting a sigh and a wagging tail, which ranks right up there amongst the cutest things I've ever seen.

But what purpose dreams serve has been elusive.  There's some contention that dreaming might help consolidate memory; that it may help to eliminate old synaptic connections that are no longer useful; and that it might function to reset neurotransmitter receptors, especially those connected with the neurotransmitter dopamine.  But last week, some neuropsychologists at Rutgers University have found evidence of yet another function of dreaming; making people less likely to overreact in scary situations.

Tom Merry, "Gladstone Dreams About Queen Victoria's Dinner" (1886) [image courtesy of the Wellcome Library Gallery and the Wikimedia Commons]

In "Baseline Levels of Rapid-Eye-Movement Sleep May Protect Against Excessive Activity in Fear-Related Neural Circuitry," by Itamar Lerner, Shira M. Lupkin, Neha Sinha, Alan Tsai, and Mark A. Gluck, we learn that people who have been deprived of REM (rapid eye movement, the phase of sleep where dreaming occurs) are more likely to experience extreme anxiety and PTSD-like symptoms than people who have been REMing normally, as well as higher activity in the amygdala -- the part of the brain associated with fear, anxiety, and anger.

The authors write:

Sleep, and particularly rapid-eye movement sleep (REM), has been implicated in the modulation of neural activity following fear conditioning and extinction in both human and animal studies.  It has long been presumed that such effects play a role in the formation and persistence of Post-Traumatic-Stress-disorder, of which sleep impairments are a core feature.  However, to date, few studies have thoroughly examined the potential effects of sleep prior to conditioning on subsequent acquisition of fear learning in humans.  Further, these studies have been restricted to analyzing the effects of a single night of sleep—thus assuming a state-like relationship between the two.  In the current study, we employed long-term mobile sleep monitoring and functional neuroimaging (fMRI) to explore whether trait-like variations in sleep patterns, measured in advance in both male and female participants, predict subsequent patterns of neural activity during fear learning.  Our results indicate that higher baseline levels of REM sleep predict reduced fear-related activity in, and connectivity between, the hippocampus, amygdala and ventromedial PFC during conditioning.  Additionally, Skin-Conductance-Responses (SCR) were weakly correlated to the activity in the amygdala.  Conversely, there was no direct correlation between REM sleep and SCR, indicating that REM may only modulate fear acquisition indirectly.  In a follow-up experiment, we show that these results are replicable, though to a lesser extent, when measuring sleep over a single night just prior to conditioning.  As such, baseline sleep parameters may be able to serve as biomarkers for resilience, or lack thereof, to trauma.

Which I find pretty fascinating.  I had sleep problems for years, finally (at least in part) resolved after a visit to a sleep lab and a prescription for a CPAP machine.  Turns out I have obstructive sleep apnea, apparently due to a narrow tracheal opening, and was waking up 23 times an hour.  I'm still not a really sound sleeper, but I feel like at least I'm not sleepwalking through life the way I was, pre-CPAP.  I also suffer from pretty severe social anxiety, and although I'm not convinced that the two are related, it is curious that the researchers found that a lack of REM ramps up anxiety.

However, even after fixing my apnea, my nights are still disturbed by bizarre dreams, for no particularly apparent reason.  I don't dream about things I'm anxious over, for the most part; my dreams are often weird and disjointed, with scenarios that make sense while I'm dreaming and seem ridiculous once I'm awake.  But what does it all mean?  I am extremely dubious about those "Your Dreams Interpreted" books that tell you that if you dream about a horse, it means you are secretly in love with your neighbor.  (I just made that up.  I have no idea what those books say about dreaming about horses, and I'm not sufficiently motivated to go find out.)  In any case, it's highly unlikely that even a symbolic interpretation of dream imagery would be consistent from person to person.

On a bigger scale, however, there is remarkable consistency in dream content from person to person.  We all have dreams of being chased, falling, flying, being in embarrassing situations, being in erotic situations.  But when you slice them more finely, the specifics of dreams vary greatly, even with people who are in the same circumstances, making it pretty unlikely that there's any kind of one-to-one correlation between dream imagery and events in real life.

So the study by Lerner et al. is fascinating, but doesn't really explain the content of dreams, nor why they can be so absolutely convincing when you're in them, and entirely absurd after you wake up.  But I better wrap this up.  I gotta go do some research in case Lucas wants to chat with me, because I might be able to hold my own when the topic is monkey junk, but I know bugger-all about rugby.

The shadow knows

One of the most terrifying sleep-related phenomena is sleep paralysis.

I say this only from hearing about the experiences of others; I have never had it happen to me.  But the people I've talked to who have had episodes of sleep paralysis relate being wide awake and conscious, but unable to move -- often along with some odd sensory experiences -- such as feelings of being watched or having someone in the room; hissing, humming, or sizzling noises; a tingling in the extremities that feels like a mild electric shock; a feeling of being suffocated; and (understandably) the emotions of fear and panic.

The reason all of this comes up is an article that appeared over at the site Mysterious Universe last week about "shadow people."  The piece was by Nick Redfern, whose name should be familiar to anyone who is an aficionado of cryptozoology; Redfern has been involved in a number of investigations of the paranormal, and is the author of books such as The Roswell UFO Conspiracy, Shapeshifters: Morphing Monsters and Changing Cryptids, The Real Men in Black, The New World Order Book, and a variety of other titles I encourage you to peruse.

So Redfern has a pretty obvious bias, here, which is why I was already primed to view his piece on the Shadow People with a bit of a jaundiced eye.  Let me let him speak for himself, though.  Redfern tells us that there are these entities that we should all be on the lookout for, and then tells us the following:

Jason Offutt is an expert on the Shadow People, and the author of a 2009 book on the subject titled Darkness Walks: The Shadow People Among Us.  He says there are eight different kinds of Shadow People – at least, they are the ones we know about.  He labels them as Benign Shadows, Shadows of Terror, Red-Eyed Shadows, Noisy Shadows, Angry Hooded Shadows, Shadows that Attack, Shadow Cats, and the Hat Man.

Shadow Cats?  Why only cats?  Cats, in my experience, are already conceited enough that they don't need another feather in their caps.  Of course, the positive side is that Shadow Cats wouldn't be very threatening.  My cats specialized in two behaviors: Sitting Around Looking Bored, and Moving Closer To Where We Are So We'll Appreciate How Bored They Are.  If their Shadow versions are no more motivated, it's hard to see why you'd even care they were around, since Shadow Cats presumably don't eat, drink, or use a litter box.  They'd kind of be a low-impact paranormal home décor item.

On the other hand, I'm just as glad there are no Shadow Dogs, because then we'd have yet another source of the really obnoxious noise that dogs make when they are conducting intimate personal hygiene, a sound my wife calls "glopping."  Our two dogs glop enough, there's no need for additional glopping from the spirit world.

But then there's "Hat Man."  On first glance, that seemed fairly non-threatening, but Redfern tells us that Hat Man is the scariest one on the list:

I sat and listened at my table [at a conference, speaking to an attendee] as he told me how, back in July of this year, he had three experiences with the Hat Man – and which were pretty much all identical – and which were very familiar to me.  He woke up in the early hours of the morning to a horrific vision: the outside wall of his bedroom was displaying a terrifying image of a large city on fire, with significant portions of it in ruins. It was none other than Chicago.  The sky was dark and millions were dead.  Circling high above what was left of the city was a large, human-like entity with huge wings.  And stood [sic] next to the guy, as he watched this apocalyptic scenario unravel from his bed, was the Hat Man, his old-style fedora hat positioned firmly on his head.  The doomsday-like picture lasted for a minute or two, making it clear to the witness that a Third World War had begun.  On two more occasions in the same month, a near-identical situation played out.  It’s hardly surprising that the man was still concerned by all this when we chatted at the weekend.

So he talked to some other people, and more than one person mentioned seeing Hat Man, and always associated with images of doom and destruction.  Toward the end, he mentions the fact that one of the people who'd seen Hat Man suffered from sleep paralysis... which kind of made me go, "Aha."

In a paper by Walther and Schulz back in 2004 entitled, "Recurrent Isolated Sleep Paralysis: Polysomnographic and Clinical Findings," it was found that people who suffered from sleep paralysis showed abnormal patterns of REM and non-REM sleep, and (most interestingly) fragmentation of REM.  REM, you probably know, is associated with dreaming; suppressing or disturbing REM causes a whole host of problems, up to and including hallucination.  Another paper -- Cheyne, Rueffer, and Newby-Clark, in 1999, "Hypnagogic and Hypnopompic Hallucinations during Sleep Paralysis: Neurological and Cultural Construction of the Night-Mare" -- has another interesting clue, which is that during sleep paralysis, cholinergic neurons (the neural bundles that promote wakefulness and REM) are hyperactive, whereas the serotonergic neurons (ones that initiate relaxation and a sense of well-being) are inhibited.  This implies that the mind becomes wakeful, but emotionally uneasy, before the brain-body connection comes back online.

[image courtesy of the Wikimedia Commons]

The problem here is that if you're in sleep paralysis, or the related phenomenon of hypnagogic experiences (dreams in light sleep), what you are perceiving is not reflective of reality.  So as creepy as Shadow People are -- not to mention "Hat Man" -- I'm pretty certain that what we've got here is a visual hallucination experienced during a dream state.

Not sure about the Shadow Cats, though.  I still don't see how that'd work.  Given my luck at trying to get my cats comply with rules such as "Stay The Hell Off The Kitchen Counter," my guess is that even feline hallucinations wouldn't want to cooperate.  If you expected them to show up and scare some poor dude who was just trying to get a good night's sleep, they'd probably balk because it wasn't their idea.  Shadow Dogs, on the other hand, would be happy to climb on the sleeping dude's bed and glop right next to his ear.  They're just helpful that way.