Can Ketamine Explain Near-Death Experiences?

In the blog of time.com yesterday there was a post on near-death experiences (NDE).
The author suggests a possible explanation: “Scientists realized that virtually all of the features of an NDE—a sense of moving through a tunnel, an out-of-body feeling, spiritual awe, visual hallucinations, intense memories—can be reproduced with a stiff dose of ketamine.”

Ketamine is actually a horse tranquilizer. It seems farfetched to suggest that we all have in our brains a secret stash of a drug like a horse tranquilizer, waiting for the moment of death to be released. But let's look further at this idea before dismissing it too fast.

The claim sometimes made about ketamine by NDE skeptics is that all (or virtually all) of the features of a near-death experience “can be reproduced” by using ketamine. But even if such a statement is true (and it probably isn't), such a statement might not mean too much. It could be that the users of the drug have a thousand and one freaky far-out experiences, and that if you cherry pick elements from a wide variety of accounts, you can piece together something resembling a near-death experience.

In this thread users of ketamine report their experiences, which include the following: closed eye visuals; sensations of being able to squeeze your fist out of existence; spatial distortions (such as shrinking rooms); mental peeking (being able to sense thoughts or feelings of others); language disintegration (hearing words that make no sense); the mind reeling with images of sex; comprehension lost; feelings of interconnectedness; time warp; “fuzzed” sensations; digitization (“Your cat walks past and the whole event happens in 8 distinct still frames one second apart”); dreamlike feelings; flesh rippling; sliding of furniture; deja vu (you think you have previously experienced whatever you are now experiencing); thought echo (your thoughts reverberate like echos); “2-dimensionalism” (in which everything seems flat); feelings of moving or contorting in space; coming back to the wrong place (“at its most extreme, re-entering your own body, but being convinced that it is the body of an alien in another, different reality”); roller-coaster sensations; visions of alien worlds.

All in all, this list is not a very good match to typical accounts of near-death experiences, although it is possible to cherry-pick particular elements and say that several aspects of near-death experiences “can be reproduced” by using ketamine.

Another web site listing ketamine experiences is here. 47 accounts are listed as “difficult experiences,”17 are listed as “bad trips,” 15 are listed as “train wrecks and trip disasters,” 30 are listed as “mystical experiences,” and 63 are listed as “glowing experiences.” Here are some random comments from the experiences listed as mystical experiences:

Everything lost its meaning
I was experiencing every emotion at once
An atomic bomb went off in my head
Total utter darkness for what seemed like forever
A feeling of living other people's lives
A feeling your body is gradually dissolving
A feeling of transcending your body and then returning to it
In a roller-coaster ride in a multidimensional giant fractal for eternity
A sensation of feeling colors
The essence of my husband and cat blended in with me and we all became one
I was floating around the Fourth Dimension 

How it feels to use ketamine

I read the 30 accounts listed as “mystical experiences,” which is the subset that should be most likely to resemble a near-death experience. None of the experiences strongly resembled the accounts given by those who claim to have had near-death experiences. Almost all of the accounts had numerous dreamlike rapid-change hallucinatory elements not found in typical near-death experiences – “acid trip” type of things. Only one of the 30 accounts mentioned a tunnel (a common element in near death experiences), but that tunnel led not to some glowing "Being of light" (as in a near-death experience), but to a vision of a pool party.

  "Pulled Through the Tunnel" -- a depiction of 

a common element in a near death experience

Some ketamine trippers did report seeing a glowing light, and some identified the light with God, but I suppose if you've taken a strong enough drug, a nearby lightbulb might look like God. Those who have near death experiences often report a strong intuition or feeling of benevolence or love coming from the mysterious glowing light they see, but I read no such accounts by the ketamine users (although there were several along the lines of “I saw this bright light, and I thought, wow, that must be God.”) I don't remember any of the accounts mentioning a sight of dead relatives (a common element of near-death experiences). A large fraction of those who claim near-death experiences seem to remember a kind of “life review.” While at least one ketamine user claimed to relive every experience he had ever had, such an experience (or an experience of “life review”) seems to be a very rare element of ketamine experiences.

Quite a few ketamine users reported being in some sense disassociated from their body (something like “beyond their body,”), as one might experience during a heavy drug trip. But in the 50 or so accounts I read, there seemed to be no users who reported floating above their bodies and looking down on them, a common element of near-death experiences.

In summary, while ketamine drug trips sometimes have some parallels with near-death experience, the typical experiences of these drug users seems to be something very different from the reports of near-death experiences, without any close similarity. One scientific paper (Corazza, 2010) reported several dozen ketamine users with experiences similar (in some ways) to near-death experiences, but the paper did not use a random sample of ketamine users – instead it specifically recruited or advertised to find ketamine users with such NDE-like experiences (which means that it gives us no idea of what fraction of ketamine users have such experiences).

But perhaps there is some other type of drug in our brains released at the moment of death – not ketamine, but something like it. There is a problem with the idea, however. We could not explain the origin of such a thing from any evolutionary standpoint, as it would have no survival value. Natural selection is only interested in giving us things that help us live long enough until we reproduce. Evolution and natural selection have not the slightest preference for whether we might have pleasant experiences at the moment of death. And if we did have in our brains some “secret stash” of something like a hallucinogenic drug or chemical released at the moment of death, we would expect that it would also be released at less traumatic moments, such as a non-fatal moment of enormous injury. But there is no evidence that any such drug or chemical is released when people have horrible non-fatal injuries.

It would seem, therefore, that there is not yet a drug that adequately explains near-death experiences. I can imagine, however, that future researchers will test various hallucinatory drugs for the sake of finding one that closely matches a near-death experience. It may not get them very far in terms of plausibly explaining the phenomenon of near death experiences, but it will no doubt be a lot more fun than classifying rare species of insects or working on quantum mechanics calculations. 
 

Road Maps to Future Immortality?

Maria Kkonovalenko recently created some cool visuals outlining three “road maps to immortality.” The first one is here, and depicts a path to immortality by genetic engineering. The second visual depicts a path to immortality by regenerative medicine. The third one is here, depicting a path to digital immortality.

The steps Maria has outlined are fascinating to ponder, but I think there are definite moral and practical difficulties we must ponder before getting too excited. First, let's look at Maria's path to immortality through regenerative medicine.

One thing Maria imagines is pigs serving as “bioreactors for growing human organs.” I have a moral issue with this proposal, which is quite similar to the moral issue I have regarding breeding pigs for slaughter. The problem is that pigs are highly intelligent and sociable animals. A scientist once made a crude video game with a large joystick cursor that an animal could manipulate with its snout. The scientist tested whether dogs or pigs could learn how to use the game. Even after many efforts, dogs were unable to learn the game, but pigs learned how to use it very quickly. So there is reason to believe that pigs are even more intelligent than dogs. Would it be moral for us to use pigs to grow some material that we would use in our body, for super-long lives? Possibly not.

Another thing Maria imagines is head transplants, and growing a new body in the lab. We can imagine the scenario: once you get to be 60, you start growing a new body in a big glass unit you keep in your basement. Then when you get to be 80, you arrange to have your head transplanted to the new body.

But there would be two big problems with this approach. The first is that while you would have a new body, you would still have the same old, aging brain. The result might look something like this:

There would also be the moral difficulty involved in growing the second body. Since a body requires a brain to function, how could you grow a replacement body without that body having its own mind and personality? If the body did have such a mind and personality, it would presumably be murder for you to have surgeons decapitate that body and replace its head with your head. Perhaps the replacement body could be set up so that it didn't have any mind. But the idea of having a mindless replacement body growing for 20 years in a lab or your basement is creepy, like the story of Frankenstein.

None of these messy biological and moral difficulties are associated with Maria's third road map to immortality, her vision of digital immortality. But I don't think the scenario she imagines is very plausible. She basically imagines that we will learn more and more about how consciousness works, by scanning and analyzing brain tissue. She imagines us concentrating on animals first, first figuring out exactly how the brain of a smaller animal works, then figuring out how the brain of a larger animal works, and then finally figuring out exactly how the human brain stores memories and produces thoughts. Then once we understand that, according to this vision, we can create computers or robots that duplicate this functionality, and upload our minds into such electronic units.

There are several problems with such a scenario. The main one is that the production of human consciousness by the brain is one of the great mysteries of nature, and there is little hope that we will be able to solve it through brain scanning. No matter how closely we examine a neuron or brain tissue with a scanning device, it seems unlikely we will ever be able to say, “Aha, there is a thought being produced,” or “I see it now; there is a memory being stored.” So brain-scanning offers little hope that we will be able to understand the brain and consciousness enough to perfectly reproduce it electronically. There is also the whole duplication problem discussed here.

We should not necessarily be depressed if digital immortality is not possible. The situation can be expressed through the flow chart shown below. The question is: is the origin of spiritual human consciousness from mere physical matter a kind of “miracle of consciousness” that can never be understood in terms of mere physics, chemistry, and biology – perhaps something that can only be understood through some more transcendent principles? If the answer to that question is “no,” then there is perhaps some hope that some of us may be able to achieve some kind of digital immortality by uploading our minds into machines. But if the answer to this question is “yes,” then there is a distinct possibility that such transcendent principles may open the door to some kind of spiritual immortality. I don't find this latter possibility to be any less hopeful than the first. 

3 Recent Studies Spoil Party of Cosmic Inflation Celebrants

In March the BICEP2 study announced observations of what is called b-mode polarization. The study was declared to be “direct evidence” for the theory of cosmic inflation, the theory that the universe underwent a period of exponential expansion during its first second. The theory of cosmic inflation (actually a large family of theories) is not the Big Bang theory itself, but a version of the Big Bang theory created to explain away certain “problems” of the Big Bang (remarkable aspects of the Big Bang which may or may not be things that should be considered as problems we need to get rid of, depending on your viewpoint).

The BICEP2 announcement was hailed as an “epic discovery,” and there was talk about scientists popping the corks of champagne bottles in a celebration. But in the past several weeks some scientific papers have been released which in various ways rain on the party of those who wanted to claim that the theory of cosmic inflation had been verified.

Almost immediately after the BICEP2 announcement, a scientific paper by Liu and others was released which casts severe doubt on whether the BICEP2 b-mode polarizations really do come from cosmic inflation or the Big Bang. The paper described a source of dust-related "galactic radio loop" radiation that may well account for the radiation detected by the BICEP2 team. The paper noted that the dust source of radiation “crosses the very region of the sky from which the BICEP 2 experiment has recently detected a B-mode polarisation signal,” and noted that this "galactic radio loop" radiation peaks at 120 to 130 gigahertz, which is almost the exact frequency used by the BICEP2 team (150 gigahertz). The paper also noted that this source of radiation was not accounted for by the BICEP2 team. The paper caused several science web sites to have stories such as this: The Big “Gravitational Wave” Finding May Have Actually Just Been Some Dust. See also this later paper by a much larger team mentioning the same source of radiation, described as "magnetic dipole emission from ferromagnetic inclusions within interstellar grains."

Another recent scientific paper raining on the party of the cosmic inflation celebrants is this paper by Hu and others. The BICEP2 findings conflicted with the findings of a much larger scientific team (the Planck team), in regard to something called the tensor-to-scalar ratio. In an attempt to resolve this discrepancy, the BICEP2 team trotted out a kind of farfetched theoretical contraption called the vanishing scalar index running model. But Hu's paper blows the whistle on this, like an NFL official throwing a flag on a football play. Hu's paper points out that when you sum up all the latest observations (from Planck, WMAP, and BICEP2) “the vanishing scalar index running model is strongly disfavored,” with a high three-sigma confidence level (a 99.7% confidence level). 

Hu's paper shows that the BICEP2 team's observations indicate a “blue tilt” in their polarization observations, and the paper notes that “this blue-tilt spectrum is not consistent with the prediction of the standard single field inflationary paradigm.” That's a big downer for the proponents of the cosmic inflation theory, as it seems to suggest that the BICEP2 observations contradict the main predictions of cosmic inflation theory, instead of confirming them. In fact, a few years back this scientific paper ended by saying, “More strikingly, if B-mode polarization is found and is shown to be due to gravitational waves, then if the spectrum is slightly blue one would have falsified the inflationary paradigm.” Such a slightly blue spectrum has apparently being found in the BICEP2 observations, an embarrassment for cosmic inflation proponents who are trying to wiggle their way out of this dilemma.

The BICEP2 B-Mode Signal: Slightly blue

Another problem for cosmic inflation advocates is a recent paper on a topic called primordial non-Gaussianity. Primordial perturbations are tiny little lumps in the cosmic background radiation, tiny little blips in the Big Bang believed to be like the seeds of future galaxies. Most versions of the cosmic inflation theory (and basically all of the simplest versions) have predicted that these primordial perturbations should be almost perfectly Gaussian, that is, having the shape of a bell-shaped curve or normal distribution. If, however, scientists find evidence that these primordial perturbations were non-Gaussian, it would almost seem to put the inflation theory on life-support. Primordial non-Gaussianity is like poison to the theory of cosmic inflation. If the cosmic inflation theory is Superman, then primordial non-Gaussianity is kryptonite.

The WMAP space satellite observed the cosmic background radiation for nine years. Quite a few scientific papers based on the data from that satellite did actually report evidence for primordial non-Gaussianity, as you can see by reading the papers here. But a team studying data from the Planck satellite reported no evidence of primordial non-Gaussianity. However, the confidence level in their study was low, only 68%.

But on April 1 of this year a team of scientists reported a study on primordial non-Gaussianity based on quasars. They found a significant degree of primordial non-Gaussianity (between 46 and 158), with a confidence of 95%, much higher than the 65% confidence level reported by the Planck team. These results are rather toxic for the theory of cosmic inflation. They suggest that the main prediction of the typical cosmic inflation theory – almost perfectly Gaussian primordial fluctuations – simply is not true. This paper has received almost no attention from the proponents of cosmic inflation, some of whom seem to fulsomely hail any study that may favor their theory, and pay little attention to studies that conflict with their theory. 

A distant quasar (Credit: NASA)

 

Fallacies of a Resource Depletion Denier

In the Wall Street Journal blog a few days ago there was an essay by Matt Ridley entitled “5 Reasons the World Is Not Running Out of Resources.” Let's look at these reasons, and see whether they give us any basis for not being very worried about the issue of resource depletion.

Reason #1 is “More Productive Land.” Ridley reasons that we have been improving the productivity of land by dumping more and more fertilizers in it, and that this trend will continue, causing more productive farmland. But this ignores the gigantic problem of soil depletion, the fact that as we try to maximize the agricultural productivity of farm land, we are depleting the organic fertility that took nature centuries to build up (through the natural decay of organisms and rocks). According to this expert, some 40% of the world's soil has been classified as degraded, and it has been estimated that we only have 60 years left of good topsoil.

Will we be able to dump more fertilizer to cover the gap? Fertilizer is created largely from natural gas, and it estimated that in sixty years we will be running short of natural gas. In short, rather than having a blessing of “more productive land,” we may have a severe problem of less productive land because of declining soil fertility.

Reason #2 on Ridley's list is “Overestimating Water Demand.” Ridley claims that during the 1960's and 1970's experts overestimated how much water the world would need. So what? Many experts during the past ten years have concluded that we will have a huge problem supplying fresh water for a growing world population, particularly with global warming (which increases droughts). You do not dismiss that concern by mentioning some alleged water overestimation that took place 40 or 50 years ago. Ridley also suggests that maybe we can use solar-driven desalination to get fresh water from sea water, but that is a pie-in-the-sky type of suggestion. Currently less than 1% of desalinated water is produced from solar energy.

Reason #3 on Ridley's list is “The Shale Revolution.” To explain why shale is no easy answer to the problem of oil depletion, let's look at what is called an oil resource pyramid, an example of which is shown in the diagram below.

At the top of the oil resource pyramid is crude oil – oil that is highly concentrated and easy to extract. As we move down the pyramid, towards its base, there are resources that are more abundant but less concentrated, and more difficult to extract. It is more expensive to extract offshore oil that crude oil; and extracting oil from tar sands is even more expensive and difficult; and extracting oil from shale is even more expensive and difficult.

The more we move down this pyramid, the lower is the energy return on energy invested (EROI). At the top of the pyramid, with crude oil, you have an energy return on energy invested of about 30, meaning you can invest one unit of energy and get 30 units of energy back. But as you move down the oil resource pyramid, the energy return on energy invested plunges. Nowadays tar sands only have an energy return on energy invested of about 3.0, meaning you have to invest one unit of energy for every three units you get back.

As we start to run out of crude oil (which may be in only a few decades), we will work our way down the oil resource pyramid, trying to extract resources that are more and more difficult to extract. At some point it will no longer be economical to extract any more oil from the resource pyramid, because the cost of extraction will be too high, and the energy return on energy invested will be too low. For example, there will be no point in investing 100 units of energy to get back only 90 units of energy from shale oil.

Once that happens, it will be just as if we have run out of oil, even though we will not have run out of oil. There will still be enormous amounts of it available in hard-to-extract resources such as shale, but it will no longer be economical to extract it.

The type of resource pyramid I have shown for oil also exists for coal and natural gas. In the case of coal, most of the reserves are lower-quality coal, as the graphic here illustrates.

So while strictly speaking it may be accurate to say that we are not running out of energy resources, it is just as accurate to say that before long our energy resources will be severely depleted. Before long, it may be effectively as if we were running out of energy resources, even though we will still have lots of hard-to-extract reserves left in the ground. This is why reason #3 offered by Ridley (“The Shale Revolution”) is not very convincing.

Ridley's reason #4 is “Alternative Sources.” For some reason, Ridley focuses here on phosphorus, which is one of the minerals we are most worried about depleting. Noting that phosphorus is vital for agriculture, and that phosphorus mines are all but depleted, Ridley suggests this is no problem because there are lower grade deposits available. But this ignores the whole “resource pyramid” issue, that when you extract a resource from the bottom of a pyramid it is much more expensive and time-consuming to get it. Ridley then gives us unintentional comedy: “If we get desperate, all the phosphorus atoms put into the ground over past centuries still exist, especially in the mud of estuaries. It’s just a matter of concentrating them again.” That's hilarious. We have no technology for extracting trace atoms from soil in any economical matter that can be used for agricultural purposes, and there is no reason to think we will have such a technology in the next seventy years. Meanwhile, long before that, we are scheduled to run out of phosphorus. Ridley's comments on phosphorus do absolutely nothing to bolster his thesis, and in fact, serve to remind us of something contrary to his thesis.

Ridley's reason #5 is “Greater Affluence and New Technology.” Ridley says the following:

In many respects, greater affluence and new technology have led to less human impact on the planet, not more. Richer people with new technologies tend not to collect firewood and bushmeat from natural forests; instead, they use electricity and farmed chicken—both of which need much less land.

This reasoning doesn't hold up to scrutiny. Yes, richer people use less firewood, but the electricity they use has an enormous environmental cost, because so much electricity is produced by coal, which is worsening global warming. In addition, there are countless environmental costs associated with supporting the lifestyles of rich people. While there are some cases of technology that decrease the human footprint on the environment, in general greater affluence leads to a greater impact on the environment, not less.

In short, all of Ridley's five reasons are fallacious. Rather than being complacent about resource depletion, we should be very worried. We have a moral duty to conserve the planet's declining resources. The best way to do that is to live a simpler life with a smaller carbon footprint. The more energy and resources each of us uses, the greater the likelihood that our children and grandchildren will suffer from our wasteful resource-depleting profligacy.  When planning a purchase of a car or house or consumer good, don't think about what will impress your Facebook friends -- think about what you need.