This is timely, as the current bookclub selection on the Discord server is The Master and His Emissary by Iain McGilchrist, and one of the most surprising indications to me has been that the corpus callosum may be as inhibitory as it is useful for connectivity. The idea really blows my mind as I imagine the incredible continuous dance that occurs in our brains! It does appear that damage to the right hemisphere creates more practical problems for humans than similar damage to the left, and that the right has both more density and connectivity within it (just a couple of the multitude of curiosities that make up McGilchrist’s hypothesis for the right being the “Master”, and the left the highly capable “Emissary”!). So I guess when someone wants to claim that one is better than the other, the proper response is “better HOW?” or “for WHAT?”. But I do think one of my reasons for finding you and Bret so important to listen to is that you each have such powerful right hemisphere capabilities and are able to synthesize information so effectively, with humor and honest panache
What a lovely comment, Zirrus--thank you. I admit that I found McGilchrist's book so dense that I did not get through the whole tome, but his hypothesis is indeed fascinating, and he is a deep and careful thinker. When Bret and I were lucky to meet McGilchrist in London a few years ago (2019 I think, at an event at which we were on stage with him and our friend Jordan Hall), I was as impressed with him in person as on the page. I was also surprised to find him adamant that his hypothesis has nothing to do with lateralization, to which is attributed things like handedness, a particular interest of mine (as a left-hander). Bret and I have posited that intellectual "difference" (diversity, if you will) that is not a severe impediment to learning but does pose challenges that a person must work around, is likely to produce novel and creative thinking. This includes yes, left-handedness, but also color-blindness, and dyslexia, and (probably) being on the mild end of the autism spectrum (if indeed "autism spectrum" is a robust description of a contiguous set of conditions, about which I am not certain).
There’s also the hypothesis that having dyslexia *comes* from having a particular genius (and perhaps the brain adapts/compensates by spending less energy investing in other brain areas) - see The Gift of Dyslexia, which I never actually read but got the gist of immediately. Anecdotally, my son has “classic” dyslexia (letters and words flip while trying to read), and I’ve never met a soul with better singing pitch/ability to mimic sounds, and just a true natural with anything musical. I’ve had a high school math teacher tell me “your son can’t count on his fingers, but he understands what math is *for*, and I don’t even expect that of my college students!”. When he was tested for his “learning disability” in first grade (I figured it out myself when he was just a toddler, but they won’t test until a kid falls behind in reading/writing), his examiner told me he’d never had such joy testing someone, and my son scored at a fifth grade level in reading comprehension. So there’s that. Probably helped that his upbringing was very book-centric, as was mine… you know, the whole nurture/nature discussion
I don't buy it--it puts too much emphasis on the innate and inborn, and insufficient emphasis (in my opinion) on environment, including development. That said, I could frame most or all of what you have identified in your son--and I've seen similar in many people--without having to fall back on "born that way" arguments.
I tend to agree, in general, Heather. ^^ my son was definitely not 'born that way', like a random throw of the dice. nope (and I got the receipts, aka lab work that corresponds to medical history, etc)
In the autism biomedical treatment community, we (mostly - as in all sciences, some aspects are hotly contested) have come to believe that the interplay between certain gene mutations and early (even prenatal! mercury amalgam fillings in ME!) exposures to toxins, cause a tipping point at which the body no longer has the ability to 'self correct' (detox) and the most detrimental genes are expressed. unhealth cascades like falling dominos. picking apart all the intertwined threads is a massive & lifelong challenge. like you and Bret say: welcome to complex systems. a truer thing has never been spoken!
And that’s very interesting as well, as many years later I learned via an excellent naturopath that I had quite elevated levels of lead and mercury… did a decade of chelation, which solved a number of food allergies and maladies for me. Complex, indeed
Interesting. His father and my brother both have forms of dyslexia, and I’ve always understood that it statistically tends to run in families especially with the men. ButI haven’t looked into any findings in a very long time. I have so many questions.
"The shape of a man’s corpus callosum tends to be different from that of a woman’s." It probably says more than I want to reveal about my own brain that I find myself more inclined to believe what you say, merely because you wrote "different from" rather than "different than."
Allow me to speculate. All mammals dream (REM stage sleep) and we can still only guess why. I suffered a TBI in 1969, and the sleep disorders that accompanied that injury have given me some insights. I believe that short-term memory is electrochemical in nature. We are conscious (to a lesser extent than most of us believe) so that consciousness must have some components of spontaneity, while long-term memory is obviously something different. I think the purpose of REM sleep is to take the memories of the day and incorporate them into the purely chemical long-term memory. This seems to happen in the corpus calleosum. Brain injuries can cause epilepsy and many of my presentations seem like a very mild form epilepsy. "Micro-petit mal" is how I describe some of my states. It only makes sense that injury to the CC can lead to sleep disorders related to REM sleep if it is indeed part of that nightly process of memory incorporation.
So far, so good, judging from our extravagant population explosion, assuming that's a useful metric. But that's usually been a challenge for a species. We are plunging headlong, cranium first ;-), into the scariest adaptive valley of our entire journey. Could be I'm a little biased on that point, not having been around for most of them, but it appears we may be encountering them at a highly accelerated rate of our own making.
Hi Heather! Are you and Brett familiar with Dr. Matt Phillips? He started with degree in evolutionary biology and is now a neurologist doing clinical trials in Parkinsons, Alzheimers and brain cancer. I'm attaching a recent interview that explains his view on how this works. Fascinating stuff!
I believe (but its been years since I read it) that the real-life inspiration for the character of 'Rain Man' was actually a man that was born without a (or severely damaged?) corpus callosum. his last name was Mot; his mother was told when he was an infant, that he would not live to be a year old, yet I believe he lived into his 50's (he died about a decade ago). one of his many savant abilities, extreme speed reading, was attributed to his eyes operating independently, so that with a book opened in front of him, left eye read the page on the left and right eye read the page on the right, simultaneously and he retained it all.
although the movie 'Rain Man' is said to be about a person with autism, the character was the furthest thing from a typical individual with autism, imho. it gave people the false impression that all with the dx of 'autism' have some kind of a savant ability. when my son with autism was little (he'll be 20 this June), strangers would ask me what his 'super power' was. ('gee, I found him on top of the fridge last week so maybe climbing??' he had no natural concept of danger; NOT a good thing.) I haven't been asked that in many years, I believe because there are now so many severely disabled (poisoned!) kids & young adults around, most realize that Rain Man, Sheldon Cooper and The Good Doctor are extreme outliers that definitely don't represent any model for what 'autism' truly is.
This is timely, as the current bookclub selection on the Discord server is The Master and His Emissary by Iain McGilchrist, and one of the most surprising indications to me has been that the corpus callosum may be as inhibitory as it is useful for connectivity. The idea really blows my mind as I imagine the incredible continuous dance that occurs in our brains! It does appear that damage to the right hemisphere creates more practical problems for humans than similar damage to the left, and that the right has both more density and connectivity within it (just a couple of the multitude of curiosities that make up McGilchrist’s hypothesis for the right being the “Master”, and the left the highly capable “Emissary”!). So I guess when someone wants to claim that one is better than the other, the proper response is “better HOW?” or “for WHAT?”. But I do think one of my reasons for finding you and Bret so important to listen to is that you each have such powerful right hemisphere capabilities and are able to synthesize information so effectively, with humor and honest panache
What a lovely comment, Zirrus--thank you. I admit that I found McGilchrist's book so dense that I did not get through the whole tome, but his hypothesis is indeed fascinating, and he is a deep and careful thinker. When Bret and I were lucky to meet McGilchrist in London a few years ago (2019 I think, at an event at which we were on stage with him and our friend Jordan Hall), I was as impressed with him in person as on the page. I was also surprised to find him adamant that his hypothesis has nothing to do with lateralization, to which is attributed things like handedness, a particular interest of mine (as a left-hander). Bret and I have posited that intellectual "difference" (diversity, if you will) that is not a severe impediment to learning but does pose challenges that a person must work around, is likely to produce novel and creative thinking. This includes yes, left-handedness, but also color-blindness, and dyslexia, and (probably) being on the mild end of the autism spectrum (if indeed "autism spectrum" is a robust description of a contiguous set of conditions, about which I am not certain).
There’s also the hypothesis that having dyslexia *comes* from having a particular genius (and perhaps the brain adapts/compensates by spending less energy investing in other brain areas) - see The Gift of Dyslexia, which I never actually read but got the gist of immediately. Anecdotally, my son has “classic” dyslexia (letters and words flip while trying to read), and I’ve never met a soul with better singing pitch/ability to mimic sounds, and just a true natural with anything musical. I’ve had a high school math teacher tell me “your son can’t count on his fingers, but he understands what math is *for*, and I don’t even expect that of my college students!”. When he was tested for his “learning disability” in first grade (I figured it out myself when he was just a toddler, but they won’t test until a kid falls behind in reading/writing), his examiner told me he’d never had such joy testing someone, and my son scored at a fifth grade level in reading comprehension. So there’s that. Probably helped that his upbringing was very book-centric, as was mine… you know, the whole nurture/nature discussion
I don't buy it--it puts too much emphasis on the innate and inborn, and insufficient emphasis (in my opinion) on environment, including development. That said, I could frame most or all of what you have identified in your son--and I've seen similar in many people--without having to fall back on "born that way" arguments.
I tend to agree, in general, Heather. ^^ my son was definitely not 'born that way', like a random throw of the dice. nope (and I got the receipts, aka lab work that corresponds to medical history, etc)
In the autism biomedical treatment community, we (mostly - as in all sciences, some aspects are hotly contested) have come to believe that the interplay between certain gene mutations and early (even prenatal! mercury amalgam fillings in ME!) exposures to toxins, cause a tipping point at which the body no longer has the ability to 'self correct' (detox) and the most detrimental genes are expressed. unhealth cascades like falling dominos. picking apart all the intertwined threads is a massive & lifelong challenge. like you and Bret say: welcome to complex systems. a truer thing has never been spoken!
And that’s very interesting as well, as many years later I learned via an excellent naturopath that I had quite elevated levels of lead and mercury… did a decade of chelation, which solved a number of food allergies and maladies for me. Complex, indeed
Interesting. His father and my brother both have forms of dyslexia, and I’ve always understood that it statistically tends to run in families especially with the men. ButI haven’t looked into any findings in a very long time. I have so many questions.
(Oh, and even though he’s a very slow reader, he literally *retains* everything. Fascinating!)
"The shape of a man’s corpus callosum tends to be different from that of a woman’s." It probably says more than I want to reveal about my own brain that I find myself more inclined to believe what you say, merely because you wrote "different from" rather than "different than."
Allow me to speculate. All mammals dream (REM stage sleep) and we can still only guess why. I suffered a TBI in 1969, and the sleep disorders that accompanied that injury have given me some insights. I believe that short-term memory is electrochemical in nature. We are conscious (to a lesser extent than most of us believe) so that consciousness must have some components of spontaneity, while long-term memory is obviously something different. I think the purpose of REM sleep is to take the memories of the day and incorporate them into the purely chemical long-term memory. This seems to happen in the corpus calleosum. Brain injuries can cause epilepsy and many of my presentations seem like a very mild form epilepsy. "Micro-petit mal" is how I describe some of my states. It only makes sense that injury to the CC can lead to sleep disorders related to REM sleep if it is indeed part of that nightly process of memory incorporation.
So far, so good, judging from our extravagant population explosion, assuming that's a useful metric. But that's usually been a challenge for a species. We are plunging headlong, cranium first ;-), into the scariest adaptive valley of our entire journey. Could be I'm a little biased on that point, not having been around for most of them, but it appears we may be encountering them at a highly accelerated rate of our own making.
Hi Heather! Are you and Brett familiar with Dr. Matt Phillips? He started with degree in evolutionary biology and is now a neurologist doing clinical trials in Parkinsons, Alzheimers and brain cancer. I'm attaching a recent interview that explains his view on how this works. Fascinating stuff!
https://youtu.be/FT0NnWhfq1E?si=i7-88ebucWx5fBjO
I believe (but its been years since I read it) that the real-life inspiration for the character of 'Rain Man' was actually a man that was born without a (or severely damaged?) corpus callosum. his last name was Mot; his mother was told when he was an infant, that he would not live to be a year old, yet I believe he lived into his 50's (he died about a decade ago). one of his many savant abilities, extreme speed reading, was attributed to his eyes operating independently, so that with a book opened in front of him, left eye read the page on the left and right eye read the page on the right, simultaneously and he retained it all.
although the movie 'Rain Man' is said to be about a person with autism, the character was the furthest thing from a typical individual with autism, imho. it gave people the false impression that all with the dx of 'autism' have some kind of a savant ability. when my son with autism was little (he'll be 20 this June), strangers would ask me what his 'super power' was. ('gee, I found him on top of the fridge last week so maybe climbing??' he had no natural concept of danger; NOT a good thing.) I haven't been asked that in many years, I believe because there are now so many severely disabled (poisoned!) kids & young adults around, most realize that Rain Man, Sheldon Cooper and The Good Doctor are extreme outliers that definitely don't represent any model for what 'autism' truly is.
Would you write, sometime, about evolutionary missteps in humans?
Depending on what exactly you mean, much of Hunter-Gatherer’s Guide to the 21st Century is precisely that.