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16.6.12

Defending Jonah Lehrer

(Edit 2012 July 30: Here we are six weeks later, and Mr. Lehrer has admitted to fabricating quotes and lying to a journalist about parts of his latest book. Obviously there is no defending this kind of behavior. This post was meant to illustrate some of the problems in neuroscientific thinking using a popular contemporary science writer. Sadly, it would appear I chose a poor horse to back on this one.)

This is a strange post for me to write because I admit I've ridden the anti-Jonah bandwagon before, advocating throwing Jonah overboard to quell the pop neuroscience storms.



Upon honest introspective reflection I admit that some of my anti-Lehrerism probably stems from righteous brain-nerd ego-driven indignation. Why does this dude get all the attention when he's not even a neuroscientist?! He's just a neuroscience roadie!

And that's not fair, and neither is all the shit he's getting.

He's taken a lot of flak lately, more so than I think he deserves. He's not a neuroscientist. He's loose with language and exaggerates or adds flourish. He's glib and fetishizes neuroscience.

But you know what Mr. Lehrer? I've come to realize something:

It's not you, it's us.

Really.

I would be more annoyed if Mr. Lehrer were intentionally distorting neuroscientific research to fit his needs, but in reading his works I don't believe he is. Full disclosure time: I've never read a single word of his books. They're not written for me. But I've been reading his columns on Wired and The Wall Street Journal and other outlets for years now.

So why is the neuroscientific community at fault for Mr. Lehrer's occasionally inaccurate scientific reporting?

Because our own house is in such disarray. Of course there are the well known issues in cognitive neuroscience, such as Vul's "voodoo correlations", "double-dipping" statistics in neuroimaging, and the dead salmon. Or our straight-up misunderstanding of basic statistics.

But some of our issues are more subtle. One of the main offenders living in our attic seems to be conflating the idea that because a brain region is active in one state--such as addiction--and in another task--such as mothers looking at pictures of their own babies--that babies are "addicting".

Or your iPhone is.

This makes about as much sense as saying that because I kiss with the same mouth-hole that I burp from, kissing and burping are essentially the same. (Note: they're usually not.)

Of course, if this logical inference were true, so too should be its converse. Maybe addiction is like having babies? Shouldn't it cut both ways?

And that's assuming that the "dopamine = reward" hypothesis is even true. Most people--neuroscientists included--take this as gospel truth. Of course dopamine equals reward! Dopamine neurons fire in response to rewarding stimuli, and the neurons "learn" to predict the rewards! Addicts' brains show activity in dopaminergic regions when shown images of drug paraphernalia. And on and on.

But--and this is apocryphal as no one would ever publish this--but from what I've heard the neurons that best predict reward values aren't in the dopaminergic brain regions. They're in the monkeys' neck muscles. Because the monkeys tense up in anticipation of reward. But few scientists would say that the neck muscle neurons are "encoding" or "predicting" reward, yet we make that fallacy all the time when we imbue neurons with that special computational power.

Oh, and by the way, dopaminergic neurons don't get any sensory inputs early enough to make a "decision" about the reward value of visual stimuli. In fact, they're probably encoding salience (relevance).



Which explains why drug users have increased activity when shown pictures of drug paraphernalia, and mothers pictures of their children, or even iPhone users pictures of iPhones versus Androids: because those things are more familiar and relevant to them.

To really hammer this point home, there is one disease we know of that is caused by the death of dopaminergic neurons: Parkinson's disease. It seems to me the clearest support for the argument that "dopamine = reward" would be seen in people missing most of their dopamine. Parkinson's patients shouldn't be able to experience any reward/pleasure because that whole system is obliterated.

Clinically, not feeling pleasure from experiences is known as "anhedonia", and a systematic review of the literature on Parkinson's and anhedonia in 2011 was inconclusive. In that review the authors found that, if anything, any signs of anhedonia in Parkinson's patients was likely caused by their associated depression.

This is very personal for me, as I watched someone very important in my life degenerate from Parkinson's disease. While an anecdote is not data, I can tell you he wasn't anhedonic. Instead he would just space out and stare all the time. Nothing seemed relevant to him.

It's not just popular writers who make these kinds of subtle scientific errors; we cognitive neuroscientists do it all the time as well.

It turns out some of our strongest neuroscientific results could very well be wrong. Or, at the very least, they're not nearly as cut and dry as they're often made out to be.

So how can we blame people like Mr. Lehrer for linking dopamine with reward when that idea has been one of the major results of systems and cognitive neuroscience of the last 30 years?

There is also the fallacy that poorly-defined (scientifically speaking) concepts such as "creativity" can be accurately studied neuroscientifically. How do you operationalize creativity, and more importantly how do you know that what you're seeing in the brain in response to your measure of creativity is the thing you think you're measuring? There's often no way to validate this.

When you ask something like "where is creativity in the brain" you assume that researchers can somehow isolate creativity from other emotions and behaviors in a lab and dissect it apart. This is very, very difficult, if not impossible. Neuroimaging (almost always) relies on the notion of cognitive subtraction, which is a way of comparing your behavior or emotion of interest (creativity) against some baseline state that is not creativity.

Imagine asking "where is video located in my computer?" That doesn't make any sense. Your monitor is required to see the video. Your graphics card is required to render the video. The software is required to generate the code for the video. But the "video" isn't located anywhere in the computer.

But if activity in that region increases as you're "more creative", clearly that's strong evidence for the relationship between that brain region and creativity, right?

Just like how when your arms swing faster when you run that means that your arms are "where running happens".

My point being, these errors are running amok in our own scientific house. Cognitive neuroscientists make these assumptions all the time.

Cognitive neuroscience grew out of experimental psychology, which has decades of amazing observations to link psychology and behavior. But with this legacy comes a lot of baggage. Experimental psychologists observed that we have the capacity for memory, attention, emotion, etc. and they sought to piece those phenomena apart.

With the advent of neuroimaging techniques, psychologists put people in brain scanners to see where in the brain behaviors "were".

But this is the wrong way of thinking about these concepts.

As cognitive neuroscientists, instead of asking, "where in the brain does this fuzzy concept occur?" we should be asking, "how can neurons give rise to behavioral phenomena that look like what we call creativity?"

Obviously I'm not saying that psychologists were doing things incorrectly. What I am saying is that we need to build upon what we've learned from decades of psychological research within a neuronal framework.

Not just stick people into an fMRI, press some buttons on a computer that say "analyze", and copy-and-paste the figures into a paper.

So Mr. Lehrer, keep up the interesting writing. Just... please be more skeptical of us. We don't know nearly as much as you give us credit for.

ResearchBlogging.org
Vul, Harris, Winkielman, Pashler (2009). Puzzlingly High Correlations in fMRI Studies of Emotion, Personality, and Social Cognition Perspectives on Psychological Science DOI: 10.1111/j.1745-6924.2009.01125.x
Nieuwenhuis, Forstmann, Wagenmakers (2011). Erroneous analyses of interactions in neuroscience: a problem of significance Nature Neuroscience DOI: 10.1038/nn.2886
Kriegeskorte N, Simmons WK, Bellgowan PS, & Baker CI (2009). Circular analysis in systems neuroscience: the dangers of double dipping. Nature neuroscience, 12 (5), 535-40 PMID: 19396166
Redgrave P, & Gurney K (2006). The short-latency dopamine signal: a role in discovering novel actions? Nature reviews. Neuroscience, 7 (12), 967-75 PMID: 17115078
Assogna F, Cravello L, Caltagirone C, & Spalletta G (2011). Anhedonia in Parkinson's disease: a systematic review of the literature. Movement disorders : official journal of the Movement Disorder Society, 26 (10), 1825-34 PMID: 21661052

50 comments:

  1. Scott R. Furtwengler11:03

    Thanks for this thoughtful essay, Dr. Voytek. We have to keep the healthy skepticism alive. I'm PhD student in Educational Psychology, hoping to explore the neural correlates of belief (attribution, self-efficacy, goal orientation, etc.). How we operationalize belief is an ongoing challenge. Your thoughts provide a good reminder that we must continue to question our methodology, data, and interpretation of the data. Thanks for the gentle reminder.

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    1. Thanks, Scott (and please, just Brad). You're trying to tackle a very difficult problem. Can you reduce "belief" into more basic components (e.g., logical constructs upon which we build higher-level belief concepts)?

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  2. Good essay.

    "In that review the authors found that, if anything, any signs of anhedonia in Parkinson's patients was likely caused by their associated depression."

    I agree with your point about how dopamine has been conflated with feelings of pleasure in some popular media, but I'm not sure if your Parkinson's example is sufficient to make this point for a couple reasons: (1) it seems like phasic dopamine release is the form that has been associated with reward (really reward prediciton error) and salience; (2) There is much more loss of dopaminergic neurons in SNc than in VTA in Parkinson's disease - the nigrostriatal pathway gets annihilated earlier and to a far greater extent than the mesolimbic "pleasure" pathway in PD.

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    1. Right, I oversimplified out RPE to just "reward" for the purposes of the post. PD is progressive, and even very advanced patients who do have DA loss in VTA don't necessarily show anhedonia as far as I can tell.

      Though this is confounded by the fact that PD causes progressive degeneration of the locus coeruleus just as much as DA neurons... which just about everyone seems to ignore....

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  3. I think your post is really interesting and eye-opening. It's good to see things from the perspective of a working neuroscientist.

    I agree that, of course, it’s important for scientists to recognise the limitations of their own work, but journalists and science communicators should be conscious of these as well. I get the impression from reading Lehrer’s more specialist writing that he is aware of the limitations and debates of neuroscience but he doesn’t seem as good at conveying this to a more general audience. And of course, why would he? People will say, why should I buy your book then?

    I think in your last sentence you really sum up the 'Jonah Lehrer problem': "we don't know half as much as you give us credit for". Because by confidently overstating the position of cognitive neuroscience, he does a disservice to science and, importantly, to his readers. We shouldn’t tolerate lax attitudes to accurately reporting the findings of science or, equally, to realistically reflecting the capabilities of current science. In this sense, I say, let the critics continue.

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    1. I'm not advocating the critics stop, I'm just trying to look at this from different perspectives.

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  4. If someone robs a bank and later discovers that the money he stole is actually fake - does that make him less culpable?

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    1. No, but if a "trustworthy" person says, "here, this is for you" and it turns out the thing they gave you was stolen, you're not at fault.

      Which is the proper analogy here (assuming good faith on Lehrer's part).

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    2. This gets into the proper role of science communication. I agree that we should not pick on individuals. I kind of disagree about the "getting the house in order" part, as exculpable as that might seem. What would that look like? Science will always be a - very messy - draft. With plenty of revisions going on all the time. That's the point. Neuroscience in particular. We are at the very beginning. But there is some appreciation of all the conceptual and methodological shortcomings in the community. I don't see that reflected much - if at all - in popular science writing. That's a problem.

      PS: That's a great analogy. 

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    3. Touche. We are always a work in progress. So how do we get journalists/writers to spot shite research?

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    4. I don't think Lehrer should be let totally off the hook in this equation. He has an undergraduate degree in neuroscience, has done some philosophy graduate work, and has been writing about neuroscience for years. If you can't see the complexity of these issues clearly after all that time, it has to be because there's some kind of flaw in your capacity to think through the science.

      According to his wiki page, as an undergraduate he did research in Eric Kandel's lab at Columbia. I was just reading Kandel's autobiography, and he's much more cautious in his claims about our knowledge of the brain than Lehrer tends to be.

      So yeah, boo to those neuroscientists who are abusing the credulity of journalist, but boo too to the journalists who are failing to exercise appropriate skepticism, particularly those who actually have the background, as Lehrer does, to see through the hype.

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  5. This comment has been removed by a blog administrator.

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    1. This comment and the deleted one below are duplicates of Björn's comment two below. No filtering going on, just culling of blogspots' dupes.

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  6. This comment has been removed by a blog administrator.

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  7. To tout my own horn, if I may :-) What you're describing is what happens when you focus on subjects - monkeys and humans - in which neither properly controlled experiments are possible nor the necessary questions can be asked with adequate experimental methodology: because of the simplicity and fuzziness of the experimental arsenal in such systems, we're forced to draw simplified conclusions. There is a feedback between the granularity of our tools and that of our thinking. Some of what you critique has been addressed (albeit only marginally, regrettably) in a more refined model system, the mouse. However, even there, the granularity is (still) lacking. Which is precisely why (here comes my horn!) the tools and experiments used in invertebrate model systems are crucial for instructing vertebrate experiments. However, it is only a minority of colleagues working in vertebrates who actually do this.

    Thus, one way to avoid the trap of oversimplification is to keep an open mind for the experiments in the technically more advanced model systems and see what level of evidence is required there to make which claims. For example, as a Drosophila researcher, I am always amazed at the resolution of yeast and C. elegans experiments and ask myself what experiments I'd need to do in order to reach the same level of evidence as these guys.

    Admittedly, I don't do that nearly as consequential as I ought to, but that only goes to show how attractive it is to stay within the comfort zone of one's own experimental system(s). Stay within that comfort zone and you'll end up with dopamine = reward.

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    1. Björn:

      "There is a feedback between the granularity of our tools and that of our thinking." I love this line and may steal it.

      So this is an age-old argument that need not necessarily be rehashed here--which model system should we use?--but I can't argue with the facts. You're right, of course, that more simplified models allow for better granularity, but at what generalizeability?

      So to refine my point, I guess what I'd like to see is greater uncertainty expressed in popular science writing. This can be done without the loss of "pizazz" I believe. Just note that if researchers learn something in humans/monkeys, there's probably a lot of experimental/design noise, and if we learning something in invertebrate models there's probably not the best generalizeability to humans.

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    2. Sorry for the multiple posts, but I never got any feedback that my post went through. I had this issue repeatedly with Blogger blogs and tried different ways of posting before I gave up :-)

      I was actually only in small part referring to direct comparisons between model systems on the mechanisms of learning. I was rather aiming towards the methodology and the kind of questions being asked. For instance the issue of necessity vs. sufficiency of certain components in learning has been a big issue for the last decade, while this kind of experiment (reconstituting a necessary component only in certain structures to test for sufficiency) has not even been done yet in, e.g. mice, to the best of my knowledge.

      I was, thus, more talking about the kind of questions being asked elsewhere that would facilitate becoming aware of the kind of questions that ought to be asked, but which, at the moment, are difficult to address experimentally in mice/monkeys/humans. If this kind of knowledge were widespread in general, everyone would be aware of th experiments still missing and wouldn't be so easily overwhelmed by the massive body of evidence all showing only different aspects of the same thing, but completely missing a whole set of crucial experiments for lack of methodological ability.

      That's sort of what I meant by the feedback loop between the granularity of our tools and that of our thinking. Direct generalizations are only one aspect of it.

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  8. Hey Brad,

    Your post is interesting, and I agree with most of the points you make, but I still don't think that it excuses poor science writing by science journalists in general, or particularly from people like Lehrer.

    Whilst cog-neuroscience papers can sometimes be overly speculative in their conclusions, they generally note limitations. The problem comes in when press releases don't go into detail on the counter-arguments, and then journalists run with headlines like "iPhones affect brain like cocaine" just because there's some NAc activity or whatever.

    My problem with Lehrer is that hes particularly fond of writing articles which draw massive, sweeping conclusions, on the basis of one scientific article, whilst apparently ignoring the rest of the literature on the subject.

    His article on frontal lobe brain damage enhancing creativity was particularly odd. Its true that there have been case studies of people with enhanced creativity following this type of brain injury, but its far more common for people to have awful deficits instead.

    Far worse than this was his "depression is good for you" article (sorry I'm not giving links to these). In this, on the basis of one study, he argued that depression might have its benefits, from an evolutionary psychology perspective. This understandably attracted a lot of criticism, from psychologists, depression sufferers and psychiatrists, who argued that whilst negative emotions in general are of course adaptive (imagine the dumb stuff you'd do if you never experienced negative emotions as a consequence of your actions) that depression is an extremely maladaptive condition (in terms of surviving and passing on your genes) and that this is because depression represents an extreme of normal emotion/mood.

    To sum up my problems with Lehrer's writing - He doesn't cite enough references to build a proper argument (most articles are based on one main paper, and maybe a couple of others to back up the argument at best) and he doesn't seem to think critically - could his argument be wrong? Is there any literature which disagrees with what he is arguing?

    Its important, because more people are reading his stuff than are reading your blog, or will read about our PhD work...

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    1. Tom:

      Well you're right, I can't really defend those pieces if they're presented as you say. Of course there is research that shows "paradoxical" improvements in some very limiteds types of tasks after frontal damage. But do those boosts in any way make up for the sometimes severe problems that also arise? I would venture to guess many would say, "no".

      Same for depression.

      If Lehrer doesn't give the negative aspects the emphasis they deserve, then that is problematic, and researchers and advocates should rightly call him out. But if he does present the severity of those conditions, but then also notes some of these interesting "paradoxical" effects, I see nothing wrong with that because frankly, I find those phenomena fascinating.

      But either way I don't think it's worth bringing out the pitchforks. I'm hoping some of the negative reviews and comments are forcing Lehrer to be more mindful of what he says. This post is sort of my way of adding to that crowd a less vitriolic reminder ;)

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  9. Interesting points, but I am in no way swayed. I think Jonah Lehrer is hyperbolic, misleading and even dangerous. Long ago, I recieved "Proust was a Neuroscientist" as a gift (thanks dad), and thought that JL ruined what could have been a perfectly interesting and entertaining book about the evolution of science and literature/art. He ruined it by trying to "Say Something" about art being better and further advanced than science. It is stupid to compare art and science as though they were two things with the same goal. And he spends a lot of time in the book trying to prove this flawed conclusion in an unscientific way.
    But while that was just annoying (Because I honestly liked the book other than that), "The Truth Wears Off" by JL in the New Yorker is downright ridiculous. It made me sick to my stomach to read his attack on science as a field that can't show real conclusions and that can't be trusted. It was the perfect fodder anti-science people because it comes from someone nominally scientific. And while there are interesting questions about reproducibility that should be discussed, JL's article was not the way to do it.
    I haven't read the imagination book, so I don't know what the current debate is about, but he's always put a bad taste in my mouth and I think he's making money and promoting himself at the cost of real science.
    I've never written about his writing on my blog or spit vitriole at him before (online anyway), but I wanted to throw my opinion in. Basically to say that it's not just his current imagination book that gets scientists riled up. I'll put the pitchfork away now.

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    1. Ahh yes... I'd forgotten about the "truth wears off" piece...

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  10. This is an awesome post for several reasons, at least in my book.
    First of all, when it comes to popular science, I am the kind of guy who comes from the "popular" edge. I've been terrible at anything scientific ever since high-school.
    But books like Jonah Lehrer's manage to do one thing that you guys (the real scientists) don't: they get me interested and fascinated about science.
    When I read that dopamine might not be about rewards at all in this post, I was like: wtf? I thought "you neuroscientists are the ones who came up with that". And your long, drawn out explanation to paint a more precise picture of currnent understand: yes, now that I already (falsely) know that dopamine is for reward (because of books written by the likes of JL) I do go through the trouble of reading it. But if I had less prior (false) knowledge and interest, you would have to put a gun to my head (or a $10 bill in front of my nose) to read that post, because to my unscientific mind it reads like this: "We have a couple of ideas, but we're not sure about any of them." And this can be utterly frustrating (and boring) to a guy like me who has no scientific training - and keep in mind with that lack of basic scientific understanding, I'm part of the world's large majority.
    I would love a book that's as easy to read and interesting as JLs which is more correct about neuroscience. Do you have any suggestions for that?

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    1. There are quite a few, actually. Off the top of my head, Rhythms of the Brain by György Buzsáki, an incredibly smart, practicing neuroscientist is an excellent book.

      Part of my hope with this blog and my other outreach efforts is to make the complexities of the science just as interesting as the "pop" sci stuff without having to sacrifice accuracy for a neat and tidy tale.

      And hey, you read this post, right?

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  11. Isn't the dopamine=reward thing is a kind of a latter day homunculus explanation. It's as if no one has actually noticed the brain is actually a very complex system, and probably too complex to understand itself, at least as a "gestalt". With our limited capabilities and a propensity for using narrative structures for understanding things we want to find little guys in the brain that are responsible for this or that but I doubt it's going to work. Narrative explanations are interesting, probably because they worked as well as anything else in the Pleistocene, and they can be very useful when appropriate, but they start to fail as systems get more complex. That doesn't stop anyone from wanting them or producing them.

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    1. Well I'd argue that the dopamine/reward thing is/was so enticing because it appears so clean and simple. "Finally!" we could say, "something in this complex mess we can hang our hats on and move forward." Sadly that does not appear to be the case...

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  12. Thank you for writing this post and including the links to your video and the PubMed etc abstracts. This is very helpful in clarifying more about dopamine and Parkinson's. I echo Bob's thoughts in that I didn't know before this post that Jonah Lehrer was not in a neurologically scientific role and with your post this is a great way to explore further - as part of the learning journey and trying to help people you care about. Thank you

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    1. Wow, thank you. I'm glad that this science communication stuff is working for some people!

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  13. I agree partly with Jim above. The problem for me seems to be that people can't help finding "personal level" meaning in brain activity, which is just a mistake. The brain is not a mind made of meat, it's a part of a much larger system (the body, environments) in which a mind inheres. Disappointing as it might be, after decades of research it seems clear that there's no simple translation between brain vocabulary and mind vocabulary. Your comparison with running is a very good one - there's no simple translation between the vocabulary of the physiology of legs and the vocabulary of running either, because running is something that the whole body does in particular relationships to its environment.

    I suspect it's just exuberance that leads people to think that if we find a neural correlate of anything that we've found the phenomenon in question, we always think the latest breakthrough in understanding something as complicated as the mind will be the last such breakthrough needed.

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    1. Hear, hear! We're definitely on the same page.

      My concern is that with so many neat "just so" stories, people will begin to suffer from "brain story fatigue" and start to get annoyed that neuroscientists aren't delivering on the promises the pop-sci writers are making (not that the scientists themselves aren't also culpable for overselling their results).

      The thing is, for guys like Lehrer, story telling is their job. And quite frankly "hey this shit's complicated" doesn't get nearly as many pageviews and ad-clicks as "scientists have found the god area of the brain".

      The TMZification of neuroscience is bad for everyone.

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  14. While I usually am wary of brain-as-computer metaphors, your "Where is the video on my computer?" example is great. I often have trouble articulating the idea of processes, ideas, memories etc being distributed in the brain rather than localized and this is quite a helpful way of putting it. Thanks!

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    1. Believe me, I am most certainly not in the "brain is a computer" camp. :)

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  15. Interesting post! I rarely comment on blogs (although I am a frequent lurker), but just wanted to mention a few things.

    I have a lot of mixed feelings about popular science writing, but it is a rare gift to be able to translate science in a digestible way. I envy a lot of these people as writers. Distilling and translating science requires some simplification. It's always a fun challenge for me to talk to reporters, because it's often hard to leave out details or nuances that seem absolutely critical from my perspective. I think a lot of writers really want to get the information correct but at the same time write an entertaining story. There are some implications here that Lehrer and others just want to make a buck and become superstars. I don't think that's fair. The majority of these folks, even people who seem like megalomaniac sellouts (::ahem:: rhymes with Windstrom), are open to feedback. They really want to know why you think they got it wrong. This is a challenging balancing act (between detailed accuracy and bite-sized). The promising thing is that there is a rising generation full of scientists (like yourself) who blog and struggle with this translation to the benefit of us all.

    The issue of getting something completely wrong in a popular science piece (e.g., depression can actually be awesome!) is also damaging in traditional science publications. We ought not to be more publicly critical of popular science writers than we are of our peers. It is easier to post about what a moron this science writer is for thinking that and writing it. He'll never be one of your reviewers! Knowledge changes rapidly. People get things wrong and then we often learn something from these errors/mistakes/misunderstandings. That's what makes this a fun job.

    And a couple points on the science:

    1) "Most people--neuroscientists included--take this as gospel truth. Of course dopamine equals reward!"

    I don't know many scientists - at least the people I regularly talk to or read - who think this is true much less gospel. Also, it sounds like when you say reward you are meaning to say pleasure. At least that may be the implication from the anhedonia and PD points. Dopamine definitely does not equal pleasure (it is certainly released when people are experiencing extreme pleasure, but this doesn't make it the primary cause). The whole wanting-liking dissociation partially cleared this up and many scientists who work in this area are on board with that. It seems that dopamine has more to do with motivation than pleasure, which is also consistent with your personal observations about PD. There seemed to be a lack of motivation (or at least an outward expression of it). While we're on the topic, people are often confused about anhedonia as well which, it turns out, can be a lot of things (e.g., http://www.ncbi.nlm.nih.gov/pubmed/20603146).

    2) The computer example is a good one. Although the full experience and expression of video is distributed throughout the physical components of the machine, there is a video card. If you "lesion" (damage) that card, you won't get video. Of course, a machine is not as plastic as a brain, so the analogy is limited. You won't see anything without a video card so the whole machine is useless. Damaging the screen would have the same effect so it's hard to pinpoint the true "cause" of video. There isn't a single true cause (maybe that's your point). But, another point is that the brain isn't either modular or distributed - it's both. Both approaches to understanding brain function are sensible and, of course, the best papers combine the two.

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    1. "It is easier to post about what a moron this science writer is for thinking that and writing it. He'll never be one of your reviewers!"

      Thank you for replying here, I really appreciate it. And that quote is spot on.

      Regarding your point 1, I admit I was intentionally over-simplifying (shame on me) to get the point across in fewer than 6 paragraphs. But the meta-point with regards to my comment about how cognitive science grew out of experimental psychology is that the very terms we're using (reward, pleasure, motivation) are sometimes used interchangeably, which leads to confusion. We don't have a proper dictionary of terms to use when referring to neural states.

      As for point 2: exactly! If you "lesion" the video card, you lose video, so early researchers would say "aha! The video card is required for video." Which is a technically correct statement, but often gets confused for "the video card is where video is". Which yes, was my point.

      As someone who has worked specifically with lesion patients[1,2], this is a particular sticking point for me, and I hope in my research I did combine both ideas.

      [1] http://www.ncbi.nlm.nih.gov/pubmed/21040843
      [2] http://www.ncbi.nlm.nih.gov/pubmed/20921401

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  16. Nice commentary, Brad.

    I agree with much of your post in that many of the thing we criticize lehrer for (with justification) we also need to criticize ourselves for (which we don't do enough).

    But I don't think this means that Lehrer's inaccuracies need to be defended, only that we need to hold ourselves to the same standards that we purport to hold popularizers like Lehrer to.

    But the last bash-on-lehrer prompted me to ask "is it more important that the public know how much we know about the world or how little?" because that seems to me to be the fundamental conflict here: as scientists, we emphasize what we don't know. What is already known is old hat. Its boring. Its the stuff of textbooks. You don't need to run experiments to discover that-which-is-already-known. Established knowledge is ONLY useful insomuch as we can look at it and say, "yes, we know X & Y, but what about Z?"

    "we know dopamine has something to do with reward, but what are the details and when does this conceptual model fail?"

    You have to be able to ask those kinds of questions (and be uncomfortable with the idea that the book is closed on a topic) in order to be a successful scientist.

    And I think that Bob's comment highlights this disconnect between scientists and the public.

    Where I think popularizers like Lehrer have failed is to appropriately balance communicating "what we know" and "what we don't know" because the two are intimately related... and without the latter, it's not really Science.

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    1. Thanks Justin. This is really getting at the heart of what I've heard many non-scientists science writers express. Most of them know that what they're saying in their story isn't 100% correct or accurate, but at some level getting that information across in any form is important for science outreach and education.

      Defining when that line has been crossed is the hard part. But judging by the negative reactions to Mr. Lehrer's more recent work, I would say that many scientists believe he has crossed it.

      What I find interesting is that within the sciences, when teaching science to students leading up to an undergraduate degree, this is a common technique. For example, most physics curricula begin with students learning about classical mechanics. And then the following semester you take E&M and the professor says, "sorry, what you learning in mechanics is correct, for certain systems, but it's actually more complicated, here's what it's really like." Then you get to quantum mechanics, and it gets less concrete and so on.

      Learning involves many levels of simplification, upon which complexity and accuracy can be built. But it needs to be done honestly and with a larger intent.

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  17. Anonymous18:14

    I feel much of the disagreement also comes from the INCREASE in scientific rigor rather than the lack thereof... If Lehrer wrote in the same style 30 years ago there would have been little backlash, but as the delta of exactitude opens from the scientific end, the journalistic end just seems more remote by comparison. Note, for example, the changing expectations in a court of law as to what level of proof is expected to remove "reasonable doubt". We've progressed from ignorance of DNA evidence, to only using it as exculpatory, to practically requiring it for conviction. Don't want to drag you too far into the weeds, but consider the analogy. What has really changed, the publications? Or our expectations?

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    1. Interesting point. I would hope that the collective "our" expectations have changed such that they demand more rigor, but that seems to fly in the face of the current level of scientific education (in the United States at least).

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  18. Anonymous23:20

    This is all interesting but is secondary to the fact that the entire field of neuroscience has been obsessed with the brain while the real action is in the heart.

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  19. Anonymous07:53

    Nice post. It reminds me of the Buddhist idea that craving only leads to an infinite set of questions. You can dig as much as you like and you will keep finding questions. The more you dig the less you actually know. Incredibly this is the scientific "200 pound gorilla" that has to be ignored by all those involved in research. Nice attempt to see it.. but also you will have to ignore it in your quest.

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  20. I would like to point out that Parkinson's occurs as a result of loss of dopaminergic neurons in the substantia nigra; these neurons are responsible for the control of movement. Dopamine and other neurotransmitters/neuromodulators are diffuse across the brain and their functional role depends on the system that they are regulating. There's no reason to think that loss of neurons in substantia nigra causes depression or anhedonia simply because they are dopaminergic neurons.

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    1. I know that, and you know that, and any neuroscientist who has spent a few minutes with the literature knows that, but it's something that many fail to grasp.

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  21. Dan H09:06

    At some point, Jonah Lehrer became one of the few neuroscience writers whose work I actively avoided. Yes, science is nuanced. Yes, there are a lot of things active scientists believe & do that are probably wrong. Yes, all this nuance and dirty laundry doesn't fit into the space of most science articles in widely read magazines/newspapers. Still, Jonah Lehrer is one of the very few writers who has gotten a podium in venues that gives him the space to express this nuance and these challenges and he wastes that privilege.

    Brad, you write, "Just... please be more skeptical of us. We don't know nearly as much as you give us credit for." It seems like Lehrer has the brain and skill to do exactly this and he's had it for a while. What's he's missing is the intellectual curiosity and the desire. His style is to use partial summaries from one or two articles as a jumping off point toward his conclusion, nuance be damned. Since this style sells books and has gotten him fame, why would he change? If he wanted to do nuance and complexity, he could. He doesn't.

    I think this would bother me less even 10 years ago, when there seemed to be fewer great neuro/psych writers, and any reasonable neuro/psych research in the public eye was a good thing. Blogs have created so many great writers that I have a bit more righteous indignation when mediocre people get the top jobs.


    For what it's worth, I don't think your dopamine/anhedonia/Parkinsons example is quite as bad as you imply. So many neurotransmitters are dose dependent in non-linear ways. For example there's the inverted U theory regarding dopamine concentrations & prefrontal function: http://brain.oxfordjournals.org/content/131/2/397.long Just because dopamine fluctuations near a normal range relate to reward processing, doesn't mean screwy things don't happen with significantly shifted baselines. The body seems to be sensitive to small fluctuations in dopamine in highly varied ways. One of the greatest research articles on dopamine variability (probably one of the greatest research articles in general) that exemplifies this nuance & complexity and is accessible to non-specialist readers is Oliver Sacks' Awakenings. Very few neuro writers can be favorably compared to Oliver Sacks, but Awakenings shows that good nuanced writing is possible, if that's the goal of the writer.

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    1. Dan, I can't argue with you on these points. Oliver Sacks' writings really helped draw me into neuroscience in general (and working with stroke patients, specifically). He does a great job.

      I'm not defending Mr. Lehrer's writings, rather I'm defending him in this post by countering his attackers.

      Wow, this post has really taken off.

      It would appear I may need to begin choosing my words much more carefully in the future. I'm losing the ability to "just muse" on here.

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    2. Dan H11:18

      Why is it a bad thing that musing generates long discussions? The key questions regarding what we expect from journalists & scientists are the same regardless of the name you use as an example. This is an interesting discussion with no easy answers... Though speaking of the name, the news on Lehrer since you wrote this post has been impressive. I wasn't impressed with him, but repeated self-plagiarism & some potential cases of plagiarizing others is surprising.

      Oliver Sacks also draw me into neuroscience, although I'm not sure I realized my reading his works & later interest in neuroscience to years later.

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    3. Dan: Definitely not bad it's just something I need to be aware of as a possibility.

      And yes, I chose the bad week to try and defend him it would seem...

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  22. Brad, what a refreshing, gracious, creative critique. Something for all of us dedicated to "translational neuroscience" especially in education, to contemplate deeply and stay connected to robust community discussion and publication world-wide.

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    1. Thanks Dr. Greenstein. The more I write the stuff the more I publicly commit myself to reinforce practicing what I preach!

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  23. Dan H06:24

    There's something that was bothering me about this issue last month & I think I've finally put words to it. Are we missing the actual fraud of Lehrer? Much like the point of your post, science is messy and even scientists oversimplify in professional situations. Here are four categories of oversimplification that, I think, sum up much of your original post's examples:

    1. Scientists may oversimplify because because we need to prioritize which nuances are worth space in a paper or time when giving a talk.
    2. Scientists might simply not know all the assumptions behind their research. That doesn't sound good, but no one knows everything. How many people have read and understood the proofs for every statistical test they've ever used? How many fMRI using psychologists can write their own fMRI pulse sequence?
    3. Scientists might decide to trust certain research more than others. Sometimes this is legitimate, sometimes it's self delusion.
    4. Scientists might actively decide to exclude past research that weakens their story (cherry picking).

    One could use the same list for science writers. In Lehrer's case:
    1. He wrote many blog posts, long-form articles, and books. In all cases, he had the luxury of space to add nuance to his articles (my point in an earlier comment).
    2. He clearly isn't a scientist but he's shown that he can read and understand a large swath of scientific literature. He read enough that he must of come across articles that contradicted his ideas.
    3/4 Is the big question. We know significant research exists that contradicted many of the stories he wanted to tell. When he came across those contradictory findings, did he convince himself that they weren't good science or did he actively ignore them to cherry pick the studies that fit his stories?

    This is obviously speculation, but if he cherry picked which studies to include in his writing, that's a greater fraud than anything that's been reported to date. I usually give science writers the benefit of the doubt, but given his intellectual abilities plus the evidence of other dishonesty... I worry.

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    1. Well you got me running off on a big rant now :)
      http://bit.ly/MyAIko

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  24. Anonymous15:44

    Suckup Karma...

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