The LSD study: you're being subtly deceived (again)

[rahli]

A new study on the neural correlates of the LSD experience has just being published, to great fanfare. Naturally, the mainstream media is all over it, because of the loaded history of psychedelics. The Guardian published an article and so did CNN, even with front-page visibility in its website. As many of my readers know, the same group that carried out this study has published other studies earlier, in which they've shown that psilocybin (the active ingredient in magic mushrooms) only reduces brain activity, instead of increasing it. See this earlier essay, as well as this one. Such results are counter-intuitive from a materialist perspective since, if brain activity indeed constituted experience, the mind-boggling psychedelic state should correlate with more brain activity, not less. So the key question of interest in this new study is this: Does brain activity increase or decrease when the subjects are under the influence of LSD?

The facts reported in the study

Let's focus on the question above and see what the study has to say about it. The researchers first show that a localized increase in cerebral blood flow (CBF) does happen in the visual cortex of the subjects. This is shown in Figure 1 of the paper, which I link below for ease of reference. The third row of images (from the top) shows the CBF difference between placebo and LSD. The small red dots at the back of the brain show the increase in CBF.

Naturally, CBF is not brain activity; it only tends to correlate with it. In previous studies, the team has found only reductions in CBF when the subjects were exposed to psilocybin, so this seems to be a discrepancy. Here is how the paper explains it:

One must be cautious of proxy measures of neural activity (that lack temporal resolution), such as CBF ... lest the relationship between these measures, and the underlying neural activity they are assumed to index, be confounded by extraneous factors, such as a direct vascular action of the drug.

The paper also suggests that magnetoencephalography (MEG) is a more reliable method for measuring actual brain activity because, unlike CBF, it measures brain activity directly. They write:

Rather than speculate on the above-mentioned discrepancy, it may be more progressive to highlight the advantages of ... MEG.

If you then look at their MEG measurement results, sure enough reductions of brain activity were observed all over the brain. This is shown in their Figure 5, linked here for convenience:

Clearly, there is a whole lot of blue, which indicates broad reductions of brain activity in the LSD state, when compared to placebo. This is what the paper actually concludes, suggesting that the localized increases in CBF observed in the visual cortex may be attributable to measurement artifacts.

What the media is reporting

This is all abundantly clear in the scientific paper but, for some reason, the media is reporting precisely the opposite! Here are some quotes from the CNN article:

Images of the brain under a hallucinogenic state showed almost the entire organ lit up with activity.

What?!

The visual cortex became much more active with the rest of the brain, and blood flow to visual regions also increased.

Huh?! "Much more active"?! This is not said anywhere in the paper. Localized increases in blood flow, as we've seen above, were indeed observed, but the researchers themselves do not conclude that this means an actual increase in brain activity, let alone the visual cortex becoming "much more active."

What's going on?

What is behind all this

The Guardian article sheds some light on what's happening here. Out of the five figures used in the original research paper, the Guardian chose to display this one in their article:

Well, not quite. They've removed all references to what the figure is actually meant to show ("V1 RSFC"), as you can see in the edited version they published. How interesting. The figure caption they added is even more peculiar:

A second image shows different sections of the brain, either on placebo, or under the influence of LSD (lots of orange).

Not only does this caption fail to mention what the figure is actually showing, it adds the evocative "lots of orange," as if it were clear what all this 'orange' means. Well, it isn't clear because the Guardian removed the explanation of what it actually means!

Let us be frank: if you were a casual reader looking at the picture, as edited and published by the Guardian, and reading its caption ("lots of orange"), what would you conclude? You would, of course, conclude that the picture shows a brain lighting up like a Christmas tree under the influence of LSD. Yet that is just about the opposite of what the technical paper says.

"What does this figure then actually mean?" I hear you ask. It's showing the measured "resting state functional connectivity" (RSFC) in the primary visual cortex (V1), a region at the back of the brain responsible for visual processing. RSFC here is a measure of how spontaneous activity in the visual cortex correlates with activity in other parts of the brain. In other words, what the paper shows is that, although brain activity, as measured with MEG, has decreased, the activity that remains is more synchronized across brain regions. This is what the researchers were referring to when they gave the following quote to the CNN article:

When the volunteers took LSD, many additional brain areas—not just the visual cortex—contributed to visual processing.

That's it; it's just as simple.

How to make sense of this?

Clearly, the Guardian journalists chose one specific figure to illustrate their article (out of the five available in the original research paper) so to show a dramatic increase in something going on in the brain under the influence of LSD. Only Figure 2 of the original paper shows this, none of the four others does. The journalists also manipulated the text in the figure itself, as well as its caption, in such a way that most readers will likely interpret this something as brain activity itself. Obviously, such editing renders the message of the Guardian article much more consistent with what people expect to see under a materialist paradigm, which states that brain activity constitutes experience. I cannot pass judgment on what the motivations or intentions of the journalists were, but their choices portray the research results as confirming materialist expectations. That the results in fact do the opposite is not discussed anywhere in the Guardian's article. Why not? Why these choices?

It gets worse. The CNN article is guilty of more than just being misleading: it's outright incorrect. To say that the results "showed almost the entire organ [i.e. the brain] lit up with activity" is sensationally wrong. The figure that likely motivated this assertion (Figure 2 of the original research paper) doesn't show raw brain activity at all, but RSFC, which is something else.

http://www.bernardokastrup.com/2016/04/the-lsd-study-youre-being-subtly.html

Edited April 13, 2016 by rahli

[-RC-]

Psilocybin reduces blood flow to to your Default Mode Network, which allows increased utilisation of the Task Positive Network.

 

Two aspects of the DMN are nodes responsible for identifying self and other, as well as time and space...

 

In a nutshell, psilocybin tells the blah-blah to shut the fuck up, and that there is no such thing as the mental constructs of time and space, or the division of ourselves from others and the world around us.

 

That's a bad thing now? I thought that was the goal of pretty much all meditative and mystical practice?

[Halcyon Daze]

I personally feel I could greatly benefit from a course of medical grade LSD.

[gtarman]

I think the brain is waaaaaay too complex for that kind of simple analysis ie. full-on experience = more electrical activity or whatever they're measuring. Just like brain size doesn't equate to intelligence. But I haven't read the article in question so maybe I'm on the wrong track

[rahli]

An author of the study responds

http://www.bernardokastrup.com/2016/04/the-lsd-study-author-responds.html?m=1

[Anodyne]

Now I know that the journalists have totally fucked the pooch on this one, but they've done it in the best way, really. They're misreporting the study, saying that psychedelics cause more brain activity than normal, right? And some people will read that as: "acid makes you think more" or possibly even "drugs make you smarter/ are good for your brain". Given all the other ways that they could have fucked up the reporting & interpretation of that study, this is better than I would've hoped for. Think of the alternative, where they said this instead: "the study showed decreased brain activity after a dose of LSD". Neither claim is accurate, but the one that is actually less false (in terms of representing the study, anyway) would have been far worse for psychedelic publicity. 

Also, am I the only one who reads the phrase "brain activity" in Homer Simpson's 'duh' voice? It's like "book-learning" or "feeling emotional", I feel a reduction in my own brain activity just reading it.

Anyway, I figure if you can't have accurate reporting, at least you get a [totally-un-scientificallly-supported] pro-drug message. I still call it a win.
 

What do you mean, "they could always try doing both"? I thought I was recklessly optimistic at times, but that's just foolishness. Are you one of those people who expected the starwars prequels to be great? Or that presidents of superpowers would be literate? Fuck, you can be hopeful, but try to restrict it to vaguely-plausible things. Accurate & honest representation of drugs in the media is not on that list. If you try to put it there your life will be a despairing spiral of disappointment and rage, probably culminating in mandated NA meetings which you will fail to appreciate the irony of.
 

 

So to those Guardian journalists I say, if you're going to arserape the scientific integrity of drug articles, thankyou for at least giving a reacharound.

[mu!]

So to those Guardian journalists I say, if you're going to arserape the scientific integrity of drug articles, thankyou for at least giving a reacharound.