SGU Episode 422: Difference between revisions

From SGUTranscripts
Jump to navigation Jump to search
(This day done.)
(NDEs done)
Line 145: Line 145:
* http://www.bbc.co.uk/news/science-environment-23672150
* http://www.bbc.co.uk/news/science-environment-23672150


S: Alright well Jay, apparently there was a study recently which has explained once and for all near death experiences.
S: Alright well Jay, apparently there was a study recently which has explained, once and for all, near death experiences.


J: Oh come onI wouldn't say once and for all.  This would probably be one of the  
J: Oh come on, I wouldn't say once and for all.  This would probably be one of the...


=== TV Watching <small>()</small>===
S: What are you skeptical?
 
J: ...of the phenomenally early studies that would encourage a lot of other studies to be done and maybe 20-30 years from now we'll have a much clearer idea.  But this study is pretty cool.  It was published in the Proceedings of the National Academy of Sciences.
 
S: PNAS.
 
J: Researchers... thank you... researchers have investigated the state of the brain during the dying process.  It's a common belief that when we're about to die our brains aren't functioning or at best operating at what has been called a significantly diminished level, right.  So you see someone dying, maybe they're bleeding out, or you're having a heart attack or whatever.  You don't expect their brain to be working in overdrive in any way or at peak performance.  And all these stories about near death experiences are part of the background noise that we all hear and I'm sure most of you guys have heard about these stories as well.  I actually know two people who had them, approximately 20% of cadiac arrest survivers report having a near death experience during what they call clinical death, which means that they weren't actually dead but their heart wasn't beating.
 
S: They were mostly dead.
 
J: Yeah.
 
R: I got better.
 
(laughter).
 
J: And a lot of these near death experiences are described by those who experienced them as hyper-real or super-intense, vivid colours, everything seems to be much more present than normal reality.  So researchers at the university of Michigan wanted to learn more about this phenomenon so they conducted experiments with 9 rats as they were dying.  Alright, so they weren't really dying, they were, I think from what I read...
 
S: Cardiac arrest.
 
J: ...they were giving them cardiac arrests probably through chemical means, more specifically though they analysed the 30 second period after the animal's heart stopped breathing.  And their reasoning was that if near-death experiences are a result of brain activity, which I can't see any other reason where near death experiences would be coming from, then the brain activity can be measured.  So if they brain is doign something then they can measure it, somehow.  They have to find out what's happening.  And what they found was pretty fascinating.  The researchers recorded and analysed the rats' brain activity through an EEG, through an Electro Encephelogram, and there was a sharp increase in high-frequency brain waves that are called gamma oscillations.  And these gamma oscillations are thought to measure the brain activity and are also suspected to be the backbone to mammalian conciousness, which I was really hoping, Steve, that you could talk a little bit about.
 
S: Well I'll tell you basically what goes on.  So brain function is a matter of lots of neurons firing together.  You don't imagine just like one little neuron firing and connecting to another little neuron.  There's also a lot of inherent background rhythms in the brain, the brain stem activation system sends this constant oscillation of activity to the cortex, like activating it.  That's why there's something like alpha rhythm when you're in a relaxed state and your eyes are closed, there's this 14Hz or so alpha rhythm going on in the background.  And that's just the inherent background activity of your brain with lots of neurons firing together.  Yeah, and it is thought that that is necessary for conciousness.  You know, you do need this sort of endless loop of these large groups of neurons firing in order for conciousness to be happening.
 
J: yeah I kind of think of it like, what do they call it, the gamma oscillation or like a computer that's pinging a million other computers on the web, like there's a constant back-and-forth communication.
 
S: Well gamma oscillations specifically, I mean they're not really fully understood, but they appear to be due to local networks firing together, like a local network maybe even paced by a single neuron which is firing at its own frequency, it's not a distributed pattern of communication among the brain.  At least that's what it seems to be at this point in time.
 
J: So in the test rats, the gamma oscillations were higher after cardiac arrest than when the animal what at, considered to be awake and healthy position or a place before they started the forced heart attack on the animal.  So in other words, all the rats displayed a widespread momentary surge of highly synchronised brain activity that had features associated with a highly aroused brain while they were post-heart attack.
 
S: Yeah.
 
J: One of the researchers said that it was feasible that the same thing could happen in the human brain in similar circumstances and that these spikes could give rise to near death visions.  And here's a quote: "This can give us a framework to begin to explain these.  The fact that they see light perhaps indicates the visual cortex in the brain is highly activate and we have evidence to suggest this might be the case because we have seen increased gamma in areas of the brain that is right on top of the visual cortex."
 
S: Yeah it's a definitely interesting study, it's just one small rat study, it's just one small rat study so obviously you need replication, it would be a lot harder to do this in people, you would have to just get lucky and be studying people who are at risk for having a heart attack.
 
J: yeah that's what they said.  They were saying that in order to confirm that this is happening in humans, they would have to be studying someone that's about to die and monitor them in the same way.
 
S: Yeah.  But there was a couple of things that come to mind in terms of this as an explanation for near death experiences.  It may be playing a role.  I don't think it's the explanation for NDE.  I agree with you Jay, obviously I think that NDEs are brain phenomena.  So people often say that, people have this heightened awareness or out of body type of experience while they were undergoing CPR, while their EEG was flat and could not possibly be generating any concious effects, but the thing is, people are remembering this much later after they've fully recovered enough to be concious from the whole thing.  They have no idea when that experience took place.  It could have taken place in the moments after the cardiac arrest started but before their brain shut down when it went through this hyperactive phase, it could have occurred afterwards when they were slowly recovering.  They have no way of placing that memory in time.  There's no way for them to say that the memory occurred while their brain was flat, while there was no EEG activity.  One other wrinkle to this, so this is assuming or taking the premise that the amount, the raw amount of brain activity correlates with the intensity of experiences of people.  And that's not unreasonable but it's also possible that decreased overall brain activity may result in increased or heightened experience because you're decreasing inhibitory parts of the brain.  It's kind of like drugs that give you hallucinogenic experiences or heightened experiences.  They're doing that more by inhibiting parts of the brain that have a massive inhibitory effect, like your frontal lobes.  Your frontal lobes, they are a complex, energy hungry, slow processing that adds a lot of higher cortical function, advanced function, but it slows everything down and it has a huge inhibitory effect on more simple and primitive parts of the brain that might give you heightened experiences.
 
J: That's counter-intuitive though isn't it?
 
S: Not if you understand how the nervous system works.  It has a basic inhibitory function, you know.  So that's often the case.  And when you inhibit or decrease an inhibitory function you get an increase in function so that's basic neuroscience.
 
J: well let me ask you a clarifying question.  So are some parts of our brains, or the functionality operating at a particular level, and that's the norm, when that's thing's on it's on at this level and then instead of the brain, the brain dials that down, instead of... it's not like lowering the volume right?  I'm trying to visualise it?  How do you see it, like what's actually happening?
 
S: No it's not really all or nothing.  I mean certain circuits might be it's either they're firing or not firing.  For example, neurons tend to fire at a certain rate.  A neuron's not on or off, a neuron is firing and that rate could go up or down.  So it is like a volume, very much so.  The rate at which the neuron is firing is increased or decreased.  And then you have lots of networks all interacting with each other and you're getting some net effect of all of that, both excitatory and inhibitory feedback and networks and connections, and there's some net effect of all of that so yeah, different parts of the brain, different networks can be functioning, operating at multiple different levels, it's not just like it's on or off.
 
E: NDEs to me seem like one of those phenomena where even if we do entirely have a grasp for it and have mapped it out front to beginning, we absolutely understand it scientifically, it will not stop people from believing that they're having some kind of out of body experience.
 
S: Yeah I mean like evolution, like pretty much anything.  If there's a pre-existing sort of religious mythological belief, yeah, the science is not going to make that go away for some people, you know?
 
E: For a lot of people.
 
S: yeah.
 
R: Jay, did any of the rats get booked for Oprah?
 
J: Well three of them did and three of them asked for too much and they didn't let them on the show, unfortunately.
 
R: I see.  I look forward to that.
 
S: I imagine they're all dead.
 
R: Shut up, what?  No.
 
J: Yeah, I thought about that.
 
R: How can they have near death experiences if they're dead?
 
E: Yeah, I thought they'd have...
 
J: Yeah I mean Steve, how did they know what the rats experienced if they didn't bring them back and talk to them afterwards?
 
S: Yeah that's true, that's a good salient point, Jay.
 
R: Yeah, like did you see your dead grandmother, etc.
 
=== TV Watching <small>(14:51)</small>===
* http://atlanta.cbslocal.com/2013/08/10/study-childrens-poor-motor-social-skills-linked-to-too-much-television-watching/
* http://atlanta.cbslocal.com/2013/08/10/study-childrens-poor-motor-social-skills-linked-to-too-much-television-watching/
=== Labor and Autism <small>()</small>===
=== Labor and Autism <small>()</small>===

Revision as of 06:25, 18 August 2013

  Emblem-pen-green.png This is the transcript for the latest episode and it is not yet complete. Please help us complete it!
Add a Transcribing template to the top of this episode before you start so that we don't duplicate your efforts.
  Emblem-pen-orange.png This episode needs: transcription, time stamps, formatting, links, 'Today I Learned' list, categories, segment redirects.
Please help out by contributing!
How to Contribute


SGU Episode 422
17th August 2013
Magenta exoplanet.jpg
(brief caption for the episode icon)

SGU 421                      SGU 423

Skeptical Rogues
S: Steven Novella

R: Rebecca Watson

J: Jay Novella

E: Evan Bernstein

Quote of the Week

It’s funny when people accuse science of being narrow merely because it asks for proof. Science expanded the number of elements from four to over 100. It expanded treatment options from bloodletting, herbs and purgatives to the untold riches we have today. It expanded the universe from a series of armillary spheres to the current, nigh-endless void. It expanded the number of worlds from two to billions upon billions. It expanded the age of the universe from 7,000 to 13.5 billion. Science expanded our senses from a tiny range of sound and light to an endless modulation of wavelengths revealing whole worlds we knew nothing about. It extended our senses from millimeters to angstroms, from kilometers to light years. Science discovered volcanoes under the oceans, terrible lizards who ruled our murine predecessors, asteroids that shattered the world, glaciers that circled the globe, the origins of man in ape rather than god. Science exposed the lie of vitalism, extended lives, cured cancer, discovered vitamins, discovered radiation (then found it was bad for us). And in the last group of discoveries, quacks were poised to kill the discoveries and loot their corpses.

William Lawrence Utridge

Links
Download Podcast
Show Notes
Forum Discussion


Introduction

You're listening to the Skeptics' Guide to the Universe, your escape to reality.

S: Hello and welcome to he Skeptics Guide to the Universe. Today is Wednesday August 14th 2013 and this is your host Steven Novella. joining me this week are Rebecca Watson.

R: Hello everyone.

S: Jay Novella.

J: Hey Guys.

S: And Evan Bernstein.

E: Good evening everybody.

J: Hey Ev.

R: Where's Bob?

S: Bob is apparently busy with work. Occasionally he has to work through the night on, he calls it "deploy" I guess they're getting a software package out there and he's got to be available to do it.

E: Wow that CIA terminology is very...

S: Yeah. I'm sure it's code for something nefarious. And we just couldn't move the record day this week, we were just locked in, so.

J: To substitute for Bob we're going to have my son Dylan. Now hold on I'll turn on his baby monitor so he can join us.

(cooing noise)

J: You hear that? Alright he's very skeptical about many things.

R: And just about as concise as bob.

J: Exactly (laughs).

S: And more coherent.

R: Aw.

J: And he doesn't talk as long.

This Day in Skepticism (1:12)

R: Hey, happy birthday to Hazel Gladys Bishop.

J: Hazel!

R: Hazel, born August 17th 1906. Have you guys ever heard of Hazel Bishop.

S: Not until tonight.

E: Uh, yeah.

J: Never.

R: Neither had I.

E: Neither has anyone.

R: Bishop was a chemist and she started her career working for oil companies. She actually, apparently she helped discover the cause of "deposits affecting superchargers of aircraft engines" during World War 2. But after World War 2, she decided to go into the cosmetics industry in her kitchen which she refitted as a lab, she developed the world's first long-lasting lipstick.

S: Wow.

R: She found the formula for lipstick that would actually dye your lips the colour that you wanted instead of just smearing stuff on top of them.

E: How long is long-lasting?

R: Well just the kind that doesn't immediately wipe off on glasses and men's collars, things like that.

J: So that was apparently a problem with the original lipstick formula, right? It just wore off very quickly?

R: Yeah and some lipsticks today too. There's differences in different lipsticks but yeah and she said at the time that she was partially inspired by the fact that at the time, women were entering the workforce in droves and she thought that it would be important for them to not have to constantly have to worry about reapplying their lipstick throughout the day when they're at the office or the factory or wherever they might be. So yeah. That's why she did it and it sold for a dollar a tube and her company did extremely well. Unfortunately she was forced out of her own company just a couple of years later and luckily though she went on to do a bunch of other cool stuff. She was obviously super smart and very adaptable. And so she, from there she became a financial analyst for companies who were interested in cosmetics and pharmaceuticals.

J: Multi-talented.

R: Yeah and then later, in 1978, she left Wall Street and she took a job teaching at the Fashion Institute of Technology in New York where she taught about chemistry and cosmetology.

S: Where NECSS is held, at least this year and probably last year.

R: That's right, yeah.

J: She sounds awesome.

R: She was pretty awesome.

S: Rebecca, I understand your soft spot for successful scientific women, but you did pass over a lot of really cool stuff for August 17.

R: Such as?

E: Here we go.

S: You want me to list some things? Well it's also the birthday of Thomas Hodgkin who discovered Hodgkin's lymphoma, a cancer.

J: Yeah but if he didn't discover it then nobody would have it today so I think he's a jerk.

S: Pierre de Fermat, Fermat's last theorem? Come on.

E: Oh yeah.

S: A lot of probing and space exploration going on on August 17th.

R: Also Paul Camera who I was considering talking about because he is one of the guys who claimed to have scientific evidence to prove Lamarckian inheritance. The reason why I didn't choose it as the main item is because it's kind of depressing. He was accused of dummying his results and he later got depressed and shot himself. So.

J: Yikes.

E: Wow.

S: That is depressing.

News Items

Near Death Experiences Explained (4:58)

S: Alright well Jay, apparently there was a study recently which has explained, once and for all, near death experiences.

J: Oh come on, I wouldn't say once and for all. This would probably be one of the...

S: What are you skeptical?

J: ...of the phenomenally early studies that would encourage a lot of other studies to be done and maybe 20-30 years from now we'll have a much clearer idea. But this study is pretty cool. It was published in the Proceedings of the National Academy of Sciences.

S: PNAS.

J: Researchers... thank you... researchers have investigated the state of the brain during the dying process. It's a common belief that when we're about to die our brains aren't functioning or at best operating at what has been called a significantly diminished level, right. So you see someone dying, maybe they're bleeding out, or you're having a heart attack or whatever. You don't expect their brain to be working in overdrive in any way or at peak performance. And all these stories about near death experiences are part of the background noise that we all hear and I'm sure most of you guys have heard about these stories as well. I actually know two people who had them, approximately 20% of cadiac arrest survivers report having a near death experience during what they call clinical death, which means that they weren't actually dead but their heart wasn't beating.

S: They were mostly dead.

J: Yeah.

R: I got better.

(laughter).

J: And a lot of these near death experiences are described by those who experienced them as hyper-real or super-intense, vivid colours, everything seems to be much more present than normal reality. So researchers at the university of Michigan wanted to learn more about this phenomenon so they conducted experiments with 9 rats as they were dying. Alright, so they weren't really dying, they were, I think from what I read...

S: Cardiac arrest.

J: ...they were giving them cardiac arrests probably through chemical means, more specifically though they analysed the 30 second period after the animal's heart stopped breathing. And their reasoning was that if near-death experiences are a result of brain activity, which I can't see any other reason where near death experiences would be coming from, then the brain activity can be measured. So if they brain is doign something then they can measure it, somehow. They have to find out what's happening. And what they found was pretty fascinating. The researchers recorded and analysed the rats' brain activity through an EEG, through an Electro Encephelogram, and there was a sharp increase in high-frequency brain waves that are called gamma oscillations. And these gamma oscillations are thought to measure the brain activity and are also suspected to be the backbone to mammalian conciousness, which I was really hoping, Steve, that you could talk a little bit about.

S: Well I'll tell you basically what goes on. So brain function is a matter of lots of neurons firing together. You don't imagine just like one little neuron firing and connecting to another little neuron. There's also a lot of inherent background rhythms in the brain, the brain stem activation system sends this constant oscillation of activity to the cortex, like activating it. That's why there's something like alpha rhythm when you're in a relaxed state and your eyes are closed, there's this 14Hz or so alpha rhythm going on in the background. And that's just the inherent background activity of your brain with lots of neurons firing together. Yeah, and it is thought that that is necessary for conciousness. You know, you do need this sort of endless loop of these large groups of neurons firing in order for conciousness to be happening.

J: yeah I kind of think of it like, what do they call it, the gamma oscillation or like a computer that's pinging a million other computers on the web, like there's a constant back-and-forth communication.

S: Well gamma oscillations specifically, I mean they're not really fully understood, but they appear to be due to local networks firing together, like a local network maybe even paced by a single neuron which is firing at its own frequency, it's not a distributed pattern of communication among the brain. At least that's what it seems to be at this point in time.

J: So in the test rats, the gamma oscillations were higher after cardiac arrest than when the animal what at, considered to be awake and healthy position or a place before they started the forced heart attack on the animal. So in other words, all the rats displayed a widespread momentary surge of highly synchronised brain activity that had features associated with a highly aroused brain while they were post-heart attack.

S: Yeah.

J: One of the researchers said that it was feasible that the same thing could happen in the human brain in similar circumstances and that these spikes could give rise to near death visions. And here's a quote: "This can give us a framework to begin to explain these. The fact that they see light perhaps indicates the visual cortex in the brain is highly activate and we have evidence to suggest this might be the case because we have seen increased gamma in areas of the brain that is right on top of the visual cortex."

S: Yeah it's a definitely interesting study, it's just one small rat study, it's just one small rat study so obviously you need replication, it would be a lot harder to do this in people, you would have to just get lucky and be studying people who are at risk for having a heart attack.

J: yeah that's what they said. They were saying that in order to confirm that this is happening in humans, they would have to be studying someone that's about to die and monitor them in the same way.

S: Yeah. But there was a couple of things that come to mind in terms of this as an explanation for near death experiences. It may be playing a role. I don't think it's the explanation for NDE. I agree with you Jay, obviously I think that NDEs are brain phenomena. So people often say that, people have this heightened awareness or out of body type of experience while they were undergoing CPR, while their EEG was flat and could not possibly be generating any concious effects, but the thing is, people are remembering this much later after they've fully recovered enough to be concious from the whole thing. They have no idea when that experience took place. It could have taken place in the moments after the cardiac arrest started but before their brain shut down when it went through this hyperactive phase, it could have occurred afterwards when they were slowly recovering. They have no way of placing that memory in time. There's no way for them to say that the memory occurred while their brain was flat, while there was no EEG activity. One other wrinkle to this, so this is assuming or taking the premise that the amount, the raw amount of brain activity correlates with the intensity of experiences of people. And that's not unreasonable but it's also possible that decreased overall brain activity may result in increased or heightened experience because you're decreasing inhibitory parts of the brain. It's kind of like drugs that give you hallucinogenic experiences or heightened experiences. They're doing that more by inhibiting parts of the brain that have a massive inhibitory effect, like your frontal lobes. Your frontal lobes, they are a complex, energy hungry, slow processing that adds a lot of higher cortical function, advanced function, but it slows everything down and it has a huge inhibitory effect on more simple and primitive parts of the brain that might give you heightened experiences.

J: That's counter-intuitive though isn't it?

S: Not if you understand how the nervous system works. It has a basic inhibitory function, you know. So that's often the case. And when you inhibit or decrease an inhibitory function you get an increase in function so that's basic neuroscience.

J: well let me ask you a clarifying question. So are some parts of our brains, or the functionality operating at a particular level, and that's the norm, when that's thing's on it's on at this level and then instead of the brain, the brain dials that down, instead of... it's not like lowering the volume right? I'm trying to visualise it? How do you see it, like what's actually happening?

S: No it's not really all or nothing. I mean certain circuits might be it's either they're firing or not firing. For example, neurons tend to fire at a certain rate. A neuron's not on or off, a neuron is firing and that rate could go up or down. So it is like a volume, very much so. The rate at which the neuron is firing is increased or decreased. And then you have lots of networks all interacting with each other and you're getting some net effect of all of that, both excitatory and inhibitory feedback and networks and connections, and there's some net effect of all of that so yeah, different parts of the brain, different networks can be functioning, operating at multiple different levels, it's not just like it's on or off.

E: NDEs to me seem like one of those phenomena where even if we do entirely have a grasp for it and have mapped it out front to beginning, we absolutely understand it scientifically, it will not stop people from believing that they're having some kind of out of body experience.

S: Yeah I mean like evolution, like pretty much anything. If there's a pre-existing sort of religious mythological belief, yeah, the science is not going to make that go away for some people, you know?

E: For a lot of people.

S: yeah.

R: Jay, did any of the rats get booked for Oprah?

J: Well three of them did and three of them asked for too much and they didn't let them on the show, unfortunately.

R: I see. I look forward to that.

S: I imagine they're all dead.

R: Shut up, what? No.

J: Yeah, I thought about that.

R: How can they have near death experiences if they're dead?

E: Yeah, I thought they'd have...

J: Yeah I mean Steve, how did they know what the rats experienced if they didn't bring them back and talk to them afterwards?

S: Yeah that's true, that's a good salient point, Jay.

R: Yeah, like did you see your dead grandmother, etc.

TV Watching (14:51)

Labor and Autism ()

Magenta Planet ()

Spontaneous Baby Combustion ()


Special Report: Onionated ()

Who's That Noisy? ()

  • Answer to last week: Richard Feynman

Name That Logical Fallacy ()

Clinical observation by experienced practitioners with a discerning mind frequently occurs decades before the sheep mentality of specific collective academic fraternities is able to satisfy itself with these new theories.

Science or Fiction ()

Item #1: A new study finds that medical testimonials that contain irrelevant information may lead to inappropriate medical decision making. Item #2: A recent study finds that listening to an emotional sermon can induce an out-of-body experience in susceptible people. Item #3: A new paper warns against “chemophobia,” the irrational fear of the ubiquitous and non-toxic chemicals found in our food and environment.

Skeptical Quote of the Week ()

It’s funny when people accuse science of being narrow merely because it asks for proof. Science expanded the number of elements from four to over 100. It expanded treatment options from bloodletting, herbs and purgatives to the untold riches we have today. It expanded the universe from a series of armillary spheres to the current, nigh-endless void. It expanded the number of worlds from two to billions upon billions. It expanded the age of the universe from 7,000 to 13.5 billion. Science expanded our senses from a tiny range of sound and light to an endless modulation of wavelengths revealing whole worlds we knew nothing about. It extended our senses from millimeters to angstroms, from kilometers to light years. Science discovered volcanoes under the oceans, terrible lizards who ruled our murine predecessors, asteroids that shattered the world, glaciers that circled the globe, the origins of man in ape rather than god. Science exposed the lie of vitalism, extended lives, cured cancer, discovered vitamins, discovered radiation (then found it was bad for us). And in the last group of discoveries, quacks were poised to kill the discoveries and loot their corpses.

J: William Lawrence Utridge!

Announcements ()

S: The Skeptics' Guide to the Universe is produced by SGU Productions, dedicated to promoting science and critical thinking. For more information on this and other episodes, please visit our website at theskepticsguide.org, where you will find the show notes as well as links to our blogs, videos, online forum, and other content. You can send us feedback or questions to info@theskepticsguide.org. Also, please consider supporting the SGU by visiting the store page on our website, where you will find merchandise, premium content, and subscription information. Our listeners are what make SGU possible.


References


Navi-previous.png Back to top of page Navi-next.png