There are lots of popular tropes of how our brain works and I'd agree with this author that they are oversimplified and generally incorrect - I'd add the left brain right brain divide to the list. However the author appears to be arguing from a position that they (or someone) actually know how the brain works - having done a neuroscience degree, my one take home was that when it comes to modelling the brain against our conscious experience - we really don't know anything.
Having done a neuroscience degree myself, I would double on your conclusion — I still have no clue how a brain works, apart of some simpler systems, like visual pattern recognition. I am out of the field for a single-digit number of years already, but in retrospective it is hilarious how all the literature in neuroscience is gently moving around the question of «guys, bit how all of it works»? People are happy to hack on single neurons or do some fishy fMRI studies instead. But of course, our tooling today is not adequate for this task.
I did a minor in neuro and had a very similar experience. Fascinating and useful but it was always slightly alarming when the professor would answer a question with "I don't know.. no one knows. That is far beyond the limits of our capabilities to know." A reminder that scientists really do work at the edge of ignorance!
That to me is really how we need to be emphasizing education in science for young people.
We tend to give the impression that we’ve figured almost everything out, and so you’re just learning the facts of it all.
Really, we’ve carved out a little island in a sea of ignorance, and the foundations of the island are just our current best rough approximations that might collapse.
An example from the field I’m in — biology. It’s quite likely that if you worked at it you can describe a new species in your backyard. You don’t have to go to the Amazon rainforest, there’s scientific unknowns all around you all the time.
This doesn’t seem to be true at least for the nervous and immune systems. Probably also the microbiome we host. There’s lots of important stuff yet to be learned with those systems.
I read the parent's comment in terms of how we once viewed life being mysterious, talking about the "elan vital" before we understood DNA. This is often used as an analogy to our current struggle to understand consciousness.
My above comment was not ironic. What I meant is that we have already discovered the algorithm that gives rise to all biological phenomena: Evolution by Natural Selection.
We also have some grand principles that further unite the field, like the cell as the basic unit of organismal life, emergent properties of higher order systems, &c.
The remaining work is mostly 'stamp collecting' - looking at the details of the output of that algorithm. Of course those details are enormously complex. Kind of like mapping out the Mandlebrot Set after you already know the algorithm.
If you wanna cure cancer, resolve chronic diseases, conserve ecosystems under climate change, etc.
It’s cool to know that DNA exists and that life evolves by natural selection, but getting into the complex weeds of that fractal is where we discover that we know so little.
This is where science communication fails, the general population and even the most curious people still think that there is such a thing as "Jennifer Aniston neuron", but in reality there is "Rachel from Friends neuron" that sits at the top of hierarchy where the signalling converges and then it's highly likely it isn't the only thing it's responsible for (OR gate), but finding what is the hard question. This is speculation stated at about 20min in this talk: https://www.youtube.com/watch?v=Y1ID0FQN9tg
Psychiatrists are doctors who prescribe substances that have been closely studied - but their effects may be easily and specifically understood, their mechanisms may not be.
Lithium is a great example - very effective treatment for bipolar. No one really knows why. Prescribed for decades as they've tried to figure it out because tests showed it was effective and relatively safe, just no one knew exactly what it was doing in there.
It's sort of how you can be a woodworker without knowing the cellular biology of trees, and without being an electrical or mechanical engineer who can build a table saw from scratch.
Lithium-rich mineral springs have historically been touted for their healing properties. It was first used for mania in the late 1800s, with Denmark leading the way, but little was published about the medication for more than half a century.
This is a good argument as to why we should look closely at traditional medicines of various cultures. We (1) coevolved with this stuff and (2) have gone through generations of trial and error.
I'm a believer in modern scientific medicine, but think we often have it backwards. Before reinventing the wheel we should exhaustively test what we used traditionally. Maybe the reason we don't do much of that is that it's not possible to patent, and so there's no financial incentive to do so?
There seems to be a good bit of different literature studying traditional cultural practices. Maybe it flies under the radar compared to flashy high-tech stuff. Below is a link to related articles about fermented beverages.
I absolutely agree with this. We should go through the many cultures' lists of traditional medicines with the lens of modern chemistry and determine what compounds lead them to be effective pharamacologically.
I've read a decent chunk of that research, but it's often relegated to backwater low-reputation journals focused on alternative medicine and is largely ignored by mainstream science. For an example, see the research on various traditional sleep-inducing drugs.
It also doesn't make its way into mainstream practice among GPs and psychiatrists. As an example, which mainstream practitioner would ever prescribe or recommend curcurmin with piperine for any condition, aside from alternative medicine practitioners? Which psychiatrist would recommend EPA fish oil for depression? I could go on. The research that does exist is largely ignored.
Not in that way, no. Pharma, on the other hand, often looks into various remedies etc. in order to draw from and produce more distilled and controllable substances. Aspirin for example, from 'cook a tree bark and drink the solution' into a pill process. Penicillin.. etc.
I am by no means an expert in pharmaceutical studies, but I suppose they can afford a huge number of dead ends in the initial phase of research due to the massive wealth and in the end, they have to test only for two variables: efficiency and side-effects. An explanation on how it actually works, is a very nice extra, but is not required. The problem for Pharma is that at some point you require tests on human subjects, which is very expensive and dangerous.
A lot of original psych drugs were also discovered by accident, intending to address some other medical issue. For example MAOIs were found to have antidepressant effects during a trial to use them for tuberculosis. Development of SSRIs (e.g. Prozac) then came from trying to create a similar drug with less side effects.
Also, the many dead ends thing is true in general for pharma, but at some point there are too many dead ends for it to be profitable even given their bankroll. This is happening a lot lately with neuro-related drug development. In the last 10 years I know Amgen, Pfizer, Novartis, Eli Lilly have all had shut downs/lay offs in their neuroscience research divisions.
> However the author appears to be arguing from a position that they (or someone) actually know how the brain works
Interesting that you had this takeaway, I didn’t get a sense of this at all. My takeaway was that the author presented modern findings (which constitute our present model for how the brain works, speaking nothing to a notion of some absolute correctness) to dispel older hypotheses that are disprovable based on the latest research. As presented, IMO, the author captures well that these modern findings are just a reference point against which to refute the stubborn tropes.
I had the same reaction to parts. This in particular:
> So why does the myth of a compartmentalized brain persist? One reason is that brain-scanning studies are expensive. As a compromise, typical studies include only enough scanning to show the strongest, most robust brain activity. These underpowered studies produce pretty pictures that appear to show little islands of activity in a calm-looking brain. But they miss plenty of other, less robust activity that may still be psychologically and biologically meaningful. In contrast, when studies are run with enough power, they show activity in the majority of the brain.
Another, more relevant reason, is that brain-scanning studies are in their infancy.
All of this seems really confused to me, or so simplified that it no longer makes any sense.
The simplest thing you can do in a scanner is have them sit there doing nothing while you acquire scans. In the end, you just have a 4d matrix of unsigned integers. For each voxel you can acquire an average over the scan and check whether it is significantly above zero using a t-test. Given enough data everything will be significantly greater than zero, including parts outside the head. Or you can compute a global mean to center all the voxles, and check which parts of the brain are significantly above the average, or significantly below the average. Extremely simple analyses (and so yes, there are lots more you could do).
In task fMRI, you have them do a task, and you use events in your task design as predictors of the BOLD, and then display a voxel map of either the beta values, or, more commonly, the T-values of those regression betas (or a contrast of those regression betas). In this case, you really aren't looking at activity. You are looking at correlations.
Those islands of activity in whole-brain analysis images in figures in papers happen because the result images are thresholded, e.g. at p < .05 false-discovery-rate correction for multiple comparisons. Personally, I think unthresholded images are better because they are more informative.
Let's take a concrete example. You have a subject do a task where they have to choose between two gambles varying in risk and reward. Then, for each voxel, you predict the BOLD time course using a series of events (time of presentation of gamble options) with magnitude equal to the coefficient of variation between the two gambles. So now, for each voxel you have a beta value showing how CoV predicts BOLD. You notice that anterior insula on both cases has the highest beta values. You threshold at conventional statistical signficance, after correcting for multiple comparions, and all the spurious, or less important, correlations drop out of the image, and you are left with two bright spots on a map pin-pointed on the left and right anterior insula. See: in this anaylysis, not all "psychologically and biolotically meaninful activity" is being examined or looked at. For example, button presses events show up localized in the motor areas too, but they weren't looking at those. But they could have, if we were interested.
The issue here is the brain of test subjects aren’t simply doing exactly one thing at a time. Your ears don’t turn off because you’re doing a memory task in an MRI.
As such it’s impossible to say what subset of brain activity is directly related to some activity rather than some related mental processes.
Not necessarily. For one, most fMRI studies will have a resting state scan to establish a baseline of what an individual's brain is doing in an MRI setting when it's not really doing anything in particular (typically having the subject stare at a fixation cross and letting their mind freely wander). Then, for the actual task, stimuli are presented and responses are recorded at very specific times with that fixation cross in between with enough time for the brain activity to return to that resting "baseline" before the next stimuli.
There's a lot of signal processing theory, regression analysis, etc. that goes in to it. With that said, the issue that arises is that only the strongest correlates may surface or be observed. There may be a lot of brain activity that overlaps or looks identical between that resting state (baseline) and the stimulation state, but can't really be included because a distinction can't be made, which goes back to your final point. That, however, doesn't mean that there aren't actual subsets of brain activity that we can attribute to a specific activity.
For example, if you're in an fMRI and I show you nothing but a fixation cross, then show you a sad image at a specific time for a specific interval, then went back to the fixation cross, and also showed you a scrambled version of that same image, I can (oversimplified) run a diff check to see what's different between the three. From there, I can remove the overlap between the three from normal baseline activity and activity specifically related to visual processing (scrambled image) to reveal what's specifically different with that sad image. If I see that the amygdala has much higher activity during that sad image compared to the fixation cross and the scrambled image, I can conclude that it has some role in emotional processing (well not really in this example because you'd also need a ton of images, including neutral images, with different orderings of each to really be confident; also really couldn't make that conclusion, just present the correlation because...science).
The point is that there are methods to isolate activity related to a specific activity/stimuli/response/etc. However, it's currently very difficult, if not impossible, to make distinctions in those overlapped areas.
Note: this is obviously an oversimplification of neuroimaging research and analysis
I think I wasn't fair in this comment, because it suggests that it is easy to do, when it actually isn't. For example, a cogntive control task might have an easy and hard condition. You'll end up with significant activation all over the brain for either of them, and their contrast will still have significant differences between the conditions all over the place too (e.g. SMA, pSMA, Anterior Insula, Anterior Cingulate, Posterior Cingulate Cortex, visual and motor cortex, cerebellum, etc. etc. etc.). Because the brain is doing all kinds of things during the task, and any "subroutine" is still going to involve communication between lot of places. But if the idea that function isn't localized, i.e. going back to a naive connectionist paradigm, then, sorry, no. The distribution of activations we get are often quite stereotyped, and if we are more careful and specific with our models we can localize function often even better.
I don’t think your point is more relevant than theirs.
It’s expensive to run brain scanning studies, so studies have smaller populations or lower resolution data collection in response. Yes, brain scanning studies are new, but we’ve been doing fMRI studies for nearly 3 decades and it’s still expensive. Had that cost been scaled back, we’d have more and/or better data because grants are (very) finite.
I'm upvoting your comment but can you clarify on left brain/right brain? I thought split-brain/callosal syndrome showed us that a lot of our ideas about left brain right brain functional divide were true.
Edit for clarification: I was not expecting folks to respond to this by linking split-brain experiments; I am specifically referring to split-brain experiments showing us that our ideas about left brain/right brain were correct. This was in reply to "I'd agree with this author that they are oversimplified and generally incorrect - I'd add the left brain right brain divide to the list" -- I want to know what this person thinks, thanks.
See Ian McGilchrist’s 2009 book The Master and His Emissary:
> McGilchrist digests study after study, replacing the popular and superficial notion of the hemispheres as respectively logical and creative in nature with the idea that they pay attention in fundamentally different ways, the left being detail-oriented, the right being whole-oriented.
Without listing the actual misconceptions some people have, it's hard to say 'the left brain/right brain divide' is a misconception since I was already aware of this understanding that they just observe in different ways, not that "left brain is creative and right is logical". I grew up with the internet, though, so my understanding didn't solely originate from grade school science books that might be simplifying this phenomenon.
Each time I lose feeling in right side of body, and lose the ability to write. Not 100%, but close enough. Typing is fine however, if slow. Critical thinking goes to crap. Talking is fine. I can still draw, though my motivation goes to crap.
Is weird what stays and what goes.
Last time I looked writing is a left brain activity. Which controls right side.
Usually the right hemisphere is linked with comprehending speech/writing, rather than producing it, so it's interesting that you lose the ability to write. Is your speech affected at all? It could be because writing involves a bunch of other more domain-general brain functions too I guess.
My best understanding (which, it's been a while since I took classes about it) is that there are some functions that tend to be more lateralized to one hemisphere or another -- with language being the prime example. However, some people do show more balanced functioning, and in some cases (more frequently among left-handed people) the lateralized functions can even be flipped from "normal".
However, there's left-brain/right-brain in terms of "some functions of the brain tend to be more on one side or another", and then there's left-brain/right-brain in terms of a pseudoscientific personality test about whether you're more of a "logical" thinker or "artistic" thinker, blah blah blah. There's no evidence for that. It's just mumbo-jumbo Buzzfeed-style quizzes to make you feel good about yourself.
More accurately, in right-handed populations subjects there is good correlation between localized brain insults and specific functional deficits. The association between brain insult locations and specific functional deficits is less strongly correlated in left-handed people and certain other subpopulations. These are also very much tendencies and not predictors for individuals.
My son has total agenesis of corpus callosum and he is 100% asymptomatic. We discovered accidentally in the last ultrasound the doctor did and confirmed with magnetic resonance.
Look into corpus callosum separation (split-brain) and some of the experiments that have been performed after this procedure. Fascinating displays of two separate consciousnesses. Sam Harris' Making Sense Podcast #234 had Iain McGilchrist to discuss this in some detail.
I would further add that those oversimplified concepts of how the brain works have hung around because they are useful for us as an abstraction to think about how our brain works.
They may be bad abstractions at a lower level of detail, but for general purposes they seem to be useful enough.
What are they useful for, though? The usefulness of wrong models, and why they hang around so long, mainly seems to be to provide income to people selling solutions.
Solutions offered based on bad simple metaphorical models have the benefit of being intuitive, so they stick around.
Theory-theory is the Efficient Market Hypothesis applied to common sense.
They are useful as a standard way to talk about the brain. If I say I am 'right-brained' in casual conversation, most people in my culture know what I mean.
Left/right divide is a myth-myth. Check out "Master and His Emissary" for the enormous amount of evidence about left/right divide.
The mirror neuron system is also a myth-myth. While there aren't "mirror neurons", per se (e.g., biochemically different), there is a system of mirroring and it is very important
I think there are a lot of myth-myths where basically the general public ran with a wildly pseudoscientific interpretation, and then the scientific community decides to dismiss the entire thing (at least outside of whatever subfield, although I've sometimes seen it within too).
Speaking specifically to left vs right brain, in popular media I've mostly seen it presented as logic vs creativity, which completely disregards that people can be creative verbally, and that certain quantitative/technical things are very non-verbal.
Obviously you know this, but the brain does localize some functions to either hemisphere, just not in the way most people think it does. My vague memory from having taken a class in psycholinguistics is that people with aphasia who've had some part of their brain damaged are good evidence of this localization.
And it's also the case that even though certain brain functions are linked with specific locations, the brain can still use plasticity to re-organize things and adapt to damage. And when you're doing any language related task, there are always going to be other more domain-general brain functions involved too, which aren't as localized.
What surprised me most about the replication crisis was that neurology actually seemed to be more affected than psychology in how non-reproducible it was.
What about using the RB/LB as a metaphor for teaching? I feel like it helps me build a ladder of abstraction for certain concepts as a music teacher. Of course I add the disclaimer that this is not ACTUALLY how your brain works, but all that neuro-jargon isn't really helpful for understanding syncopation...
I get the author's beef with the idea that discrete brain areas peform discrete tasks - if there's one thing my neuroscience MSc taught me it's that the brain processes things in parallel rather than series, which is what most of those theories rest on - but I think part of the issue is that we try to impose existing words, like "memory", onto the brain. One of the more productive lines of thinking I used when studying was trying to throw out all of those definitions and try to work from first principles about the kind of processing various areas were doing. Of course it's impossibly complex to get understand it in totality (which is probably partially what drives specialising in particular brain areas), but discarding the limits imposed by language really helped me think more flexibly about what it might be doing.
Also, a small nit about the way it was presented was using plasticity (i.e. areas area able to perform different kinds of processing if the inputs change, e.g. blindfold + braille) as evidence of non-specialisation. That's doesn't follow. Just because neurons can be flexible doesn't mean they're not performing a discrete task, although I agree with the general conclusion.
> I think part of the issue is that we try to impose existing words, like "memory", onto the brain
This is also what Freud meant by "time doesn't exist in the unconscious". What we call memory isn't discrete like RAM, nor is it organized around what we perceive as time, these are illusions of how we experience perception and consciousness. He described by suggesting we imagine the modern city of Rome, then, directly physically overlay ancient Rome on top of modern Rome, physics be damned, if an ancient column goes through a modern building, then it goes through the modern building without destroying it, directly occupying the same space at the, er, same time
> a small nit about the way it was presented was using plasticity ... as evidence of non-specialisation. That's doesn't follow.
A small nit about your small nit: The article does not make that claim. Quote:
> I’m not saying that every neuron can do everything, but most neurons do more than one thing.
I mean, it's kind of obvious that all neurons are far from completely interchangeable, like RAM cells on a memory chip, since there clearly is quite a bit of higher level architecture.
I would like to add one more myth the list. The idea that we all have a finite amount of brains cells.
They used to teach that we’re all born with a certain amount of brain cells, and over time from aging, or getting a concussion, or if you ‘do drugs’, you would lose said cells. And that’s that. No more new brain cells :)
We know this to be false now. I don’t know how much this one has persisted, I haven’t heard it in a while. But it was drilled into my head as a kid.
Not related to brains, but another health myth that comes to mind is the idea that our tounges & taste buds are divided into ‘zones’ that perceive the different flavors. I don’t remember the order, but something like the tip tastes sweet, the middle is umami, the sides are sour, et cetera.
Now we understand all taste buds taste all flavors. Is is interesting these old models science came up with to try to explain things, and how long some of them persisted.
PS: Check out the 2002 album ‘Phrenology’ by the Roots. It’s a classic!
I believe there is at least one prominent exception in the hair cells in the inner ear. These are not replaced once they rupture - producing the distinctive tinnitus sound at the frequency they monitor. Or perhaps I'm mistaken in this — it's been a while since my studies!
Sure. I’m not an expert or anything, but the term ‘neurogenesis’ would be what you want. I guess the fact that many neurons are formed in the womb, and last our whole lives still holds true, but the realization that at least some parts of the brain continuously generate new cells is significant.
From the introduction: ”For a long time, it was thought that the nervous system is fixed and incapable of regeneration. Although it is indeed true that most neurons in the brain are generated before birth and are never exchanged, it is now well established that new neurons are continuously generated by stem cells in at least two discrete regions in the brain throughout life in most mammals: the hippocampus—a seahorse-shaped structure underneath the cortex that is important for memory formation and cognitive functions; and the olfactory bulb (OB)—a structure located above the nasal cavity that is important for the sense of smell.”
To be honest, after reading a little more, I’m a little unclear on if ‘all taste buds taste all flavors’. I might be wrong to say it like that. I saw one thing that said there are actually different types of receptor cells, but they are not isolated into zones, and somewhat evenly distributed across the whole tongue.
I wouldn't say that the Triune brain theory is a 'myth'. It's just not accurate, but it's not a complete lie either. There certainly are different parts of the brain that have evolved at different times, and have different functions.
The older parts have evolved to specific functions, while neocortex, which is found in mammals, has a uniform structure and is capable of learning and adapting to different tasks. 75% of human brain is neocortex.
The article also has this weird notion that the only source of evidence of the Triune brain theory are brain scans. We also have evidence Wilder Penfield's work stimulating parts of the brain. We also have evidence from damage to the brain, from physical injury, lesions, tumors, surgeries, strokes, etc.
While that data shows that brain functions aren't strictly fixed and neuroplasticity is a thing, it does show that locations in the brain do have disproportionate impact on certain functions.
Barrett's views are not the only ones there are, and they are still debated in the field, however much she may insist to the media that her view is the only correct one and that all else are myths. Things are not nearly as settled as she claims.
Panksepp, J. (2007). Neurologizing the Psychology of Affects: How Appraisal-Based Constructivism and Basic Emotion Theory Can Coexist. Perspectives on Psychological Science, 2(3), 281–296. https://doi.org/10.1111/j.1745-6916.2007.00045.x
Panksepp, J. (2008). Cognitive Conceptualism—Where Have All the Affects Gone? Additional Corrections for Barrett et al. (2007). Perspectives on Psychological Science, 3(4), 305–308. https://doi.org/10.1111/j.1745-6924.2008.00081.x
Yea, I think that in some ways the “myths” presented can be seen as abstractions that lack details for the sake of being digestible. It is also a fair point that these abstractions can be poorly carried to detailed conclusions like the example of humans being essentially more evolved; I think that’s the bone to pick
This article takes obvious simplifications/generalizations and tries to act like it's all wrong because they're simplifications/generalizations. Obviously simplifications leave out detailed minutiae, that's the point. It doesn't mean the general concept is wrong, it just means that there's more to it once you get into the details.
I'm not an expert on the topic, but as Jeff Hawkings says in the video, the differences are caused by the fact that different areas of neocortex are connected to different inputs. The underlying structure is uniform, which can adapt to different inputs.
I'm no expert at all on neuroscience, but when I recently got the opportunity to read a transcript of the lecture titled The Value of Science by Richard Feynman, it filled me with awe and reverence. I can't but share a sizable quote from the same.
“For instance, the scientific article may say, 'The radioactive phosphorus content of the cerebrum of the rat decreases to one- half in a period of two weeks.' Now what does that mean? It means that phosphorus that is in the brain of a rat—and also in mine, and yours—is not the same phosphorus as it was two weeks ago. It means the atoms that are in the brain are being replaced: the ones that were there before have gone away. So what is this mind of ours: what are these atoms with consciousness? Last week's potatoes! They now can remember what was going on in my mind a year ago—a mind which has long ago been replaced. To note that the thing I call my individuality is only a pattern or dance, that is what it means when one discovers how long it takes for the atoms of the brain to be replaced by other atoms. The atoms come into my brain, dance a dance, and then go out—there are always new atoms, but always doing the same dance, remembering what the dance was yesterday.”
I recall some debate around the oldest buildings, and how (I think) the Ise Grand Shrine [1] is disqualified because it is rebuilt regularly -- for the past 2000 years. Of course, one may resolve this by more carefully defining "oldest building", but this quote by Feynman makes me lean towards a definition that includes this shrine. Who are we to say that some building is different because the atoms of its beams came from different trees, and in the same breath claim individual continuity across decades in the face of this fact about our brain?
While it's not a fixed function pipeline, there is some level of correlation between 'brain damage at site x' and 'effect y' so while phrenology is bunk, the brain is also not just a blob of compute.
I was really annoyed by that one because the "areas of brain do different tasks" hypothesis has very little to do with phrenology, which is about how studying the shape of the skull might tell you things about the personality and thus has very little to do with the brain itself. And is complete bunk, unlike the brain regions thing which is not simple but does have some basis in fact as you pointed out.
The central thesis is excellent, but this really caught my eye:
> Depression is usually catalogued as a mental illness, but it’s as much a metabolic illness as cardiovascular disease, which itself has significant mood-related symptoms. These two diseases occur together so often that some medical researchers believe that one may cause the other. That perspective is steeped in Cartesian dualism. Both depression and cardiovascular disease are known to involve problems with metabolism, so it’s equally plausible that they share an underlying cause.
I wish this to be true. I'm in excellent cardiovascular health - low BP, 60 bpm resting heart rate, extensive cardio/endurance activity 4-5 days per week. Utterly miserable every waking hour.
I struggle with depression for periods of time but have mostly always been fit. In my experience, even though it's contrary to most "broscience" out there, diet helps more with depression than working out.
What working out does definitely improve is my sex drive and self-esteem, so it's important to know what's the triggers for your depression, as it may help anyway.
As someone who has dealt with anxiety, depression, and OCD, I am truly sorry that you have to go through that. I don’t know if you’ve talked to doctors about it, but if you found their support lacking, please keep trying. It took 5 different doctors, psychs, and therapists before I finally found a team of professionals that could treat my OCD effectively. And they really did help.
I don't want to be too critical, because I've learned a lot from the author's books, but a fair amount of the article (mainly myths 1 and 2) seem to be over-generalization or skewed based on the author's bias. Her field is psychology, not primarily neuroscience; specifically, the psychology (and some neuroscience of) emotion. I recommend Jeff Hawkins's new book for a perspective closer to a neuroscientist's. (He's technically not a neuroscience Ph.D., but he has equivalent knowledge.)
Myth #1: Brain areas aren't separate and didn't evolve in stages.
1. Brain (neocortex) areas aren't single-purpose. Obviously neuroplasticity is a thing, but the article ignores that areas of the brain develop to be focused on a single category of tasks (visual, auditory, etc.). The author's example, blindfolding someone and watching their visual cortex get repurposed when learning to read braille, ignores that if you don't blindfold them, other areas will probably take up most of the task of learning braille because it's not a visual activity and the brain tends to separate areas of responsibility.
2. The number of significant evolutionary steps may not be just three, so the triune brain theory may be technically false, but I've never seen any actual neuroscientist argue that it isn't roughly accurate. The evidence in the article is molecular genetics: the fact that there aren't radically different kinds of neurons. This is like scaling up an argument that ethanol and glucose are the same thing because they share the same elements. If the limbic system and neocortex have roughly the same kind of neurons, what does that matter? We know they serve radically different purposes, and we know that reptiles don't have a neocortex (at least, nothing of significance).
Myth #2: Brain is stimulus/response machine
Her argument against this myth seems tortured. Of course the brain is not a simple impulse/response machine, but it's still essentially taking in inputs and responding in various ways. It just has a mind-bogglingly complex internal state.
Myth #3: Strong dividing line between diseases of the brain and body
Everything seems to point to her being right on this one. Science knows, nearly as much as it can know anything, that neurological stress leads to physical stress responses which can screw up other parts of the body, often through hormone dysregulation. Similarly, physical problems from gut health to inflammation can trigger immune responses or simpler biochemical reactions that have neurological side-effects. And, of course, diet. Psychoactive drugs are a clear example of how an external physical influence can have psychological effects.
> Myth #3: Strong dividing line between diseases of the brain and body
> Everything seems to point to her being right on this one.
The problem is that most of the time people debunk this "myth" they are using some motte-and-bailey tricks.
First, there is no perfect dividing line between disease of the brain and body, but there is also no perfect dividing line between diseases of the brain and differences of the brain (do domestic abusers have bad character or a disease?) or between diseases of different organs. Nevertheless, it is highly useful to have a taxonomy of phenomena that cuts reality roughly at its joints. These divisions have important practical and moral implications, and they fact that there are gray areas does not mean the categories should be undermined.
Second, these seemingly scientific "there is no line" arguments are almost always used asymmetrically by experts to advance a normative position, e.g., my psychological disease should be treated like a physiological disease by the law and my friends because there is no perfect distinction between the psychological and physical. It is possible to go in the other direction and argue that many/most alleged psychological diseases are really just different preferences and should be treated as such; see Thomas Szasz:
This is just as well supported by "there is no line" argument as folks who want physiological-psychological disease equality. The reason the latter position is more popularly is based on values.
I was originally against the authors take on Myth one as well, but then I considered that my perspective may have been somewhat different from the one they were actually talking about and I sort of incorrectly translated it. Maybe they were speaking directly against a much more harsh version of the 'each part of the brain does one thing' than we interpret it. Not as a 'the visual cortex handles most of our conscious sight' but 'the visual cortex only handles sight and all sight is handled by the visual cortex only'. That is much stricter and much quickly disproven. As someone with an interest in neuroscience, I have long since been exposed to evidence that would prevent me from ever considering the second idea as being the possible answer, but perhaps others have not. If we consider someone who has myths on how the brain works but has never taken as much as an intro psychology class and instead bases their opinion on what they hear in passing from others, such as news sources or daily talk shows, then it is possible some people have the second idea as their mental model for the brain.
If that is the case, then I do think the author has made a slight blunder because the audience who would read their article is unlikely to include significant portions of people who would've lacked the exposure needed to have that much stricter and more incorrect mental model, and thus the author could've done better to present the myth so as to not confuse it with the not as incorrect mental model of the brain that their likely readers have.
> Her argument against this myth seems tortured. Of course the brain is not a simple impulse/response machine, but it's still essentially taking in inputs and responding in various ways. It just has a mind-bogglingly complex internal state.
The author was dispelling the myth that a significant fraction (or all) of neural activity happens between the time of the stimulus and time of the response, which is probably a common misperception.
I'm not somebody well informed about neuroscience hence apologies if I'm implying something that's against the common knowledge in your domain. One impression upon reading articles like these seems to be that there's a lot of research and curiosity about the way brain works together but the core model of "brain is composed of communicating neurons" seems to be generally accepted. Does that suggest that we already understand how a single neuron behaves in isolation? I'm mainly interested in the microscale model from the perspective of simulation, for example in the Wiki page of the Human Brain Project (https://en.wikipedia.org/wiki/Human_Brain_Project) among the obstacles it's mentioned that "detailed neuron representations are very computationally expensive", does it mean that we already cracked the microscale, i.e., defined exactly how a neuron behaves in a computational (mathematical) model? Perhaps the substantial intricacies of the brain can also arise in the microscale level depending on cellular mechanisms, nutrition and other side effects?
obviously, Jerry Fodor was wrong. But anyone who studies cognitive science still gets this stuff shoved down his throat. The followers will however claim there's a difference between the brain and the mind.
from Wikipedia:
"For Fodor, significant parts of the mind, such as perceptual and linguistic processes, are structured in terms of modules, or "organs", which he defines by their causal and functional roles. These modules are relatively independent of each other and of the "central processing" part of the mind, which has a more global and less "domain specific" character. Fodor suggests that the character of these modules permits the possibility of causal relations with external objects. This, in turn, makes it possible for mental states to have contents that are about things in the world. The central processing part, on the other hand, takes care of the logical relations between the various contents and inputs and outputs"
For me the takeaway is that all the "myths" mentioned in here are often simplified abstractions, but they do have underlying truth.
> Brains don’t work by stimulus and response.
They definitely do, eg. when you accidentaly touch a hot object. But that's not all they do. They also have a predicting mode of operation.
> specific parts of the human brain have specific psychological jobs
There are parts of the brain doing specialized things, otherwise why do we still call an area of the brain "visual cortex"? But the brain is much more malleable and plastic than we thought earlier, and entire areas can be repurposed.
> According to this myth, the brain is like a collection of puzzle pieces, each with a dedicated mental function. One puzzle piece is for vision, another is for memory, a third is for emotions, and so on.
The author makes too much about parts of the brain not being specialized.
As a neurosurgery resident in a former life who actually operated on brains and took care of people with strokes and trauma, yes, different parts of the brain are specialized to do different things. Yes, there is plasticity, but there are limits to it, especially once you reach adulthood.
I will give some anecdotes, but these are very, very typical.
Example, frontal lobe and impulse control. Saw an older patient with a giant tumor in the frontal lobe. His family came with him. Seeing where the tumor was, I asked the family if they had noticed any recent decline in his impulse control. Their response: "Now that you mention it,..." and out came all sorts of stories how their previously very proper father, was now doing all sorts of very things with very poor judgement and had even gotten in trouble with the law. If your frontal lobes get damaged, you will have issues with impulse control, long term planning, etc.
Another example is speech. Speech is very localized to areas of the left brain. As an example, there was patient with seizures in the left brain so bad that we would have to remove parts of the brain to control them. We did a surgery where we opened up the skull, and then woke the patient up. Psychologists asked the patient to do various verbal tasks, while we touched different parts of the brain with an electrode. When the electrode touched the parts of the brain that control speech, the effect was instantaneous, the patient suddenly stopped talking mid-word. By doing this, were were able to map precisely which parts were being used for speech, and in the surgery, avoid those areas. The patient had a very good outcome with his seizures stopped, and still able to speak.
Another example is movement disorders. Worked with a surgeon who is a world class expert in deep brain stimulation. In there you precisely place an electrode into a specific part of the brain and turn it on. Once you do that, you can have someone with severe tremor or Parkinson's who has been unable to even write their name for years, suddenly are able to write. You turn off the electrode, and the effect goes away. If the electrode is off by a millimeter, it does not work. It has to be precisely positioned.
In terms of mental illness, I have seen patients with severe depression and obsessive, compulsive disorder improve significantly after precise placement of an electrode in the correct part of the brain.
This thing about parts of the brain specializing is not just abstract theory. It is used every day by neurosurgeons, neurologists, etc to make life and death decisions. It has a lot of real world evidence backing it up. The most important question to answer when you see someone with a stroke or brain trauma, is "where is it located?" The same size injury can have vastly different effects on the person depending on where it is.
Your examples of localised point effects such as speech and Parkinsonian tremor responses to probes don't negate the article's observation that brain functions are distributed, and regions participate in multiple functions.
By way of analogy, you can disable a car sooner or later by breaking the ignition switch or the gas tank lid. But those points are not alone responsible for the transportation function of the car.
The wheels of the car are involved with and vital for acceleration, steering, and braking. Without transmission and suspension, wheels do none of this.
The transmission of the car is capable of both propulsion and braking.
To think of speech as a function of a small part of the left side of the brain is incomplete. Speech requires a number of motor, sensory, respiratory and data systems to work together in a coordinated pipeline that exists across the whole brain and body. The neurons involved in those circuits also work to perform other functions.
I’m firmly in the zone of “I don’t know what I don’t know” when it comes to neuroscience but the hard emphasis on the areas of the brain not being specialised was in stark contrast to literally everything I’ve read about the brain and neuroscience to date.
I wonder if the author is pushing both sides of the coin of “myth” and “reality” way to far to the extremes.
I agree with another commenter that perhaps the author is trying to push back against older, more rigid ideas of much more extreme separation of functions of the brain in a more primitive sense.
But some detail is lost here, because as far as I’m concerned (and I’m heartened by the support that your more experienced and expertise-led comment provides) the brain absolutely and demonstrably has specialised areas that focus on certain functions.
So in an effort to bust these “myths” I feel parts of this article just serve to muddy the water and add some confusion rather than clarity.
I learned how to draw from the book “drawing on the left side of the brain”. I’m not so sure about the neuroscience parts, but if you want to draw/paint, get that book.
All my sites looked terrible until I learned to paint.
>Brains, however, don’t work by stimulus and response. All your neurons are firing at various rates all the time. What are they doing? Busily making predictions.
Is this a polling system...
Oh actually more like a branch predicting system...
> The 21st century is a time of great scientific discovery. Cars are driving themselves.
These are the first two sentences of the article and already I'm skeptical. I'd say the self-driving cars are mostly a product of recent technical inventions and not scientific discovery - the scientific discovery happened mostly in the XX century, with discoveries which made integrated circuits, or lasers (for lidar) possible.
The deep learning concept itself did not "discover" anything, it's just a technical contraption that happens to work well for some classes of real-world problems. Granted, there were some maths advances in the eighties and nineties that made current SLAM possible, but again, new math is not "scientific discovery".
You're being overly pedantic over the exact difference between "scientific discovery" and "technical invention", a discussion which is completely irrelevant to the article.
That line isn't even important to the article, it's just a bit of flowery language intended to frame the subject of myth vs. fact.
Okay, but pedantry aside, the 20th century kicked the 21st century's ass when it comes to scientific discovery. Some stuff discovered between 1900 and 1920:
- Relativity
- Atomic nuclei
- Darwinian modern synthesis
On the technological application side, there was the airplane and mass production of cars, plus the growth of telephony and radio.
In the 21st century we have:
- found a bunch of extra solar planets but the work really started in the 90s, lol
On the application side, we have the cellphone/smartphone revolution and continued penetration of the internet, plus consumer EVs and solar panels. Not nothing, but the smartphone is the biggest change to daily life. Everything else is more just refinement of what came before.
I can't really think of other things that are profound scientific discoveries versus technical applications or filling in of minute details. We're just clearly in the far side of the S curve now, and the 20th century was the rollercoaster.
In much the same way that much of 2020's progress was actually started from the 20th century, much of e.g. the year 2060's progress will be stuff actually started from 2020. We likely systemically underestimate the use of today's discoveries simply since the big stuff mostly isn't useful yet.
I agree that we still don't totally know what happened 2000–2020, but e.g. the Eddington eclipse proof of relativity was 1919 and Einstein became an international celebrity around then.
I think I am underrated some math discoveries since it's not an area I follow, e.g. the Poincaré conjecture proof is probably a big deal. On the other hand, when did Poincaré make his conjecture? 1900. So in a certain sense, we are backfilling a known gap.
I feel like it was greatly due to the WWII. Those and so many other discoveries were the direct result of programs like project manhattan.
Maybe the human species really needs to be pushed to extinction to further tξhe human enterprise or maybe it was just the crazy funding similar to bell labs.
I'd just expect an author to be precise when writing something that will be read by thousands of people, as opposing to just spitting out some flowery language.
Wish someone had told me that I wasn't doing real science before I started in academia, would have saved me a lot of time and effort.
On a more serious note, seems like weird gatekeeping of what constitutes scientific discovery and what doesn't.
Scientific discovery is learning new facts about the world. Inventing new contraptions to help us in our goals is technology. I.e. I don't think anyone would call Henry Ford a scientist or Albert Einstein an inventor. I thought it's basic and well-understood distinction.
If you follow the constructivist philosophy of science (spoiler alert: I do) then absolutely Albert Einstein is an inventor. He invented a mental model (essentially a lossy compression) of some parts of reality that better fit observed phenomena than its predecessor. Our mental/scientific models are not descriptions of reality; objective reality is unknowable. What they are, are tools (technologies!) that we can use to predict effect, given a cause and a state.
Is constructivist philosophy of science an independent axiom or does it have testable predictions? E.g. is there a function from theorems of ZFC to {invented, not invented}?
it's a philosophy, so no it doesn't have testable predictions - but neither does objectivism, its counterpart. But then, testable predictions don't tell you about the nature of reality so c'est la vie.
> is there a function from theorems of ZFC to {invented, not invented}?
Can you derive definitions of inventions versus discoveries from set theory? No, probably not. You can't derive the smell of a rose from set theory either though so it's probably not a very good theory of everything.
I completely agree with you and I don't think it's being pedantic at all. Clearly the 21st century is bearing the FRUIT of scientific discovery and we're seeing incredible iteration and innovation that is very exciting. But much of this is the result of things which were DISCOVERED in the 20th century.
Language is important. "Discovery" means something just as "inventing" means something. I see these words used all the time for things like websites (Facebook/Twitter) or computer hardware (Apple products most notoriously). Something can be a wonderful and very popular implementation without being either a discovery or an invention. Often these larger things DO contain many smaller real discoveries and inventions along the way! But people always seem to be referring to the end product as a whole, which I find bizarre.
