Category Archives: neurology

Slapen: waarom?

Ik heb zojuist “Why We Sleep”van Matthew Walker afgelezen. Dat is een van de beste non-fiction boeken die ik in twee jaar gelezen heb.

Aan de ene kant slapen

Ik had al lang geleden een uitstekende populairwettenschappelijke boek over het thema gehad, Counting Sheep van David Martin. Dat was interessante mengeling van biologische en culturelle, vooral literaire aspecten van slapen en dromen. Walkers boek brengt nieuwe aspecten met zich, het focus is eerder de gezondheid van de mensen, zelfs als het ook in het boek van Martin eerover ging.

Hier een paar van de thema’s in dit boek:

Hoe werkt precies – zeer precies – cafeïne en welke uitwirkingen die eigenlijk heeft

Wat is eigenlijk de nucleus suprachiasmaticus

Hoe functioneert het circadiaan ritme en melatonine

wat is concreet slapen, hoe fonctionnert de REM-slaap en hoe de non-REM-slaap, o.a wat doen onze neuronale netwerken erbij precies

wat doen andere dieren en hoezo kwam het ertoe

wat doen de mensen specieel die andere dieren niet doen bij het slapen

hoe verandert zich slapen met tijd – spoiler: oudere mensen hebben zoveel slaap nodig als iemand die 20 jaar oud is-

slapen en creativiteit

slapen en opmerkzaamheid

en dutje doen of niet

kanker, slaap en levensverwachting

overgewicht, DNA en slapen

dromen en nut, zeer concreet voor REM en non-REM

slaap en ziekten van het slapen

hoe de maatschapij tegen slapen ging, slapmiddelen en veel meer

slapen, werken, artsen, ziekenhuizen

een nieuwe vizie voor slapen

Ik kan het boek van harte aanbevelen. Ik heb vele puncten hier en daar gelezen maar niet zo in detail en zo goed uitgelegd.

En hier een goede video:




The creative brain

I just finished the second book on the brain by Dick Swaab. I do not think the English translation has come out yet but if you read Dutch, here you have a reference about it.
This time Swaab focuses, as the Dutch title indicates, on creativity on a general scale: how it is generated, how it is shaped by our genes, by the way children develop in their mother’s wombs, by every single thing that happens to them, to us, until our deaths.

The book is written with the usual dry Dutch humour. It has lots of references to the ailments and quirks of artists, scientists and other people.

The book can become very technical but for someone really interested in the brain, it is a trove of information. It has very good references and a really complete index.

The only thing I wish could have been done better is the images on the different brain parts – there are several small pictures mostly at the start and at the end of the book. Thinking about this I thought it could be good to have something like an online search where you can enter terms about the brain and a 3-D-like visualization rotates, gets zoomed in o or out. That would be the perfect addition for this book. But perhaps I am asking too much. It would be a nice application, though, for people like me, a layman, who want to understand a bit more about our brains.

A little bit of everything on and in the brain

I have read a few books on brain and neurology and I was not sure about getting this one by Dutch physician and neurobiologist Dick Swaab, “Wij zijn ons brein” (We are our brain in English). I am glad I did, even though  I have some criticism to the book.

There are 22 chapters (including the conclusions) covering topics from brain development, the brain in the womb, sexual differentiation, sexual development, hormones, emotions, consciousness, electrical stimulation, morals, memory, free will, death and evolution. There are some tough stories, a few jokes, lots of brief accounts on research past and present and some general recurring themes that Swaab wants to address.

One thing that shocked me was the author’s profound aversion to sports…unless those sports are chess or bridge. Although he often stresses the importance of evidence his arguments against  are extremely biased in this area: he basically refers to physical damage produced by high impact sports. I am not a health specialist but a simple search on the Internet for peer-reviewed articles on the benefits of (moderate) sports do give some interesting results.

I found it was a pity Dr Swaab did not include a biography. I know this is a book for laymen like me but even people like me want once in a while to read a little bit more about this or that.

Another beautiful mind

Now I am currently reading “A Mind for Numbers: How to Excel at Math and Science” by Barbara Oakley. It is a magnificent book. I am just finishing the third chapter and I know it is one of the best books I have read in the last 12 months. She basically gives lots of insights about learning processes with a focus on mathematics and science but basically for everything. She quotes a few of the authors I have appreciated before like Terrence Deacon. She dispels several myths. I have read quite a few books on neuroscience – for laymen and speciaists – and some on learning in general. There are everywhere good pieces of advise, useful reminders of things most of us know, some new approaches. She is yet another one of those authors and yet she describes the importance of some of them is very good: ways for switching between a focused and an unfocused mode of thinking, for instance, or about dealing with the Einstellung effect.

I am just starting and I am very happy.

Computing a mind

Some time ago I finished Ray Kurzweil’s “How to create a mind, the secret for human thought”. The book is definitely worth reading, also for someone working in any sub domain of artificial intelligence.

We are beyond this, surely

We are beyond this, surely

Kurzweil recapitulates his work on artificial intelligence and relates it to the latest research on how minds – biological minds, to be more specific – work. I found funny he goes into some of the work Nuance is carrying  out with medicine and semantics. I worked on some items from a company called Language & Computing which Nuance acquired several years ago.

One of the chapters I liked the most was chapter 4, The Biological Cortex. I have read a few popularizing books on neurology and a few more technical articles about neurological research, but there were a few new items to me here. Chapter 5 is also pretty fascinating for me. Obviously, the neurological part is the one where I am an absolute layman. By all means this makes me want to read more about it.

Kurzweil states the basic units of the neocortex are modules composed of around one hundred neuros. According to him – and some other researchers – connections within each module are mostly inherited, they are based on our genes, whereas connections between modules are above all the product of experience, of training.

Chapter 7, the Biological Inspired Neocortex is the one with the most things where I wanted to gloss over, but I still read it through. Here I started to find more things I have my second thoughts about. Firstly, Kurzweil claims somehow that although “no human can claim to have mastered all of Wikipedia…[it] is only part of Watson’s knowledge base. Is it? I do not thin so. I have worked a lot with Wikipedia and have studied a zillion projects trying to garner as much new semantic information as possible in the most reliable way (a lot of these projects providing data for DBPedia, but a lot more to private companies) and I wouldn’t say we are even close to producing a “full” extraction of Wikipedia information. How would it even look like? Even if we are talking about a purely statistical analysis of Wikipedia pages: what does that mean? Statistics are, one way or the other, attached to a model, to a hypothesis. How many hypotheses can we create from any middle-size page of Wikipedia?

Kuzweil warns about how difficult the concept of consciousness is and how even the most rational scientists can get into the vaguest rumblings here. And yet, for me he fails to deliver here. He gets as fuzzy as anyone else. In that chapter 7 he goes over the Turing test and makes his predictions about when a computer will pass the Turing test. He discusses Searle’s Chinese room and argues that if if what Searle said about that room is true, “the human brain would not be judged capable of thinking either”.

Perhaps the issue I have is that I don’t agree even with what the Turing test is supposed to mean. We recently saw how the University of Reading competition went. When I read the dialogues that made a third of the judges believe they were dealing with a human being, I was surprised, to put it mildly, that anyone could fall for it. Now, we need to ask: what is the difference between the 1/3 who believed the bot was a human and the 2/3 who didn’t? I don’t think the answer is “they are less clever”.  At least I think that cannot be the only explanation. I reckon the 1/3 of gullible people know less about what we know today of what kind of reactions we can automate.

I think consciousness, at least as we see it in humans, is very related to a very deep degree of self-reference, the existence of a system that is aware of itself, of itself being aware of itself and and so on recursively. If we relate this system to the idea of the Chinese room: human consciousness would be capable not only of acting as a Chinese room towards the external world, but of creating internal, virtual Chinese rooms it can analyse on itself and in itself, virtual Chinese rooms and other kinds of rooms it can think of.

All in all, although Kurzweil tends to exaggerate here and there, his writing is readable, he provide some interesting pieces of information for everyone and he contributes to the discussion about how we can build more intelligent computer systems.

Consciousness according to Antonio Damasio

I just read Self Comes To Mind, a book by neurologist Antonio Damasio. It was a fascinating reading.  Be warned, though: you need to have some knowledge about the anatomy of the brain. Even if there is an appendix with some general description about a human brain’s structure, it is not really very complete. Damasio seems to repeat himself quite often. Even so, if you like reading about the brain, you might enjoy this book.

Damasio describes how the homeostasis of living creatures might have helped in developing a neural system. This system enabled animals to adapt in increasingly more sophisticated ways  to their surroundings. The author identifies three main components of the “self”: the proto-self, the core-self and the autobiographical self. He then describes how different regions of the brain are active in the different levels. Human consciousness ultimately appears when sensory experience, as mapped by our brains, interact with previously recorded experiences.

The critical part is when Damasio explains how the convergence-divergence zones act, the processes of forward and feed-backward transmission of information, how our most inner representations of the images interact and help further shape the incoming information. And this is something that kept reminding me of On Intelligence, a wonderful book by Jeff Hawkins about his theory of the mind and – lo and behold – how this theory can help in developing artificial intelligence.

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Nr 2 are the colliculi superiores. Did you know what they are for?