The Human Mind

Book review: The Ego Tunnel: The Science of the Mind and the Myth of the Self, by Thomas Metzinger.

This book describes aspects of consciousness in ways that are often, but not consistently, clear and informative. His ideas are not revolutionary, but will clarify our understanding.

I didn’t find his tunnel metaphor very helpful.

I like his claim that “conscious information is exactly that information that must be made available for every single one of your cognitive capacities at the same time”. That may be an exaggeration, but it describes an important function of consciousness.

He makes surprisingly clear and convincing arguments that there are degrees of consciousness, so that some other species probably have some but not all of what we think of as human consciousness. He gives interesting examples of ways that humans can be partially conscious, e.g. people with Cotard’s Syndrome can deny their own existence.

His discussion of ethical implications of neuroscience points out some important issues to consider, but I’m unimpressed with his conclusion that we shouldn’t create conscious machines. He relies on something resembling the Precautionary Principle that says we should never risk causing suffering in an artificial entity. As far as I can tell, the same reasoning would imply that having children is unethical because they might suffer.

Book review: Beyond Boundaries: The New Neuroscience of Connecting Brains with Machines and How It Will Change Our Lives, by Miguel Nicolelis.

This book presents some ambitious visions of how our lives will be changed by brain-machine and brain to brain (“mind meld”) interfaces, along with some good reasons to hope that we will adapt well to them and think of machines and other people as if they are parts of our body. Many people will have trouble accepting his broad notion of personal identity, but I doubt they will find good arguments against it.

But I wish I’d skipped most of the first half, which focuses on the history of neuroscience research, with too much attention to debates over the extent to which brain functions are decentralized.

He’s disappointingly vague about the obstacles that researchers face. He hints at problems with how safe and durable an interface can be, but doesn’t tell us how serious they are, whether progress is being made on them, etc. I also wanted more specific data about how much information could be communicated each way, how precisely robotic positioning can be controlled, and how much of a trend there is toward improving those.

Book review: Too Loud, Too Bright, Too Fast, Too Tight: What to Do If You Are Sensory Defensive in an Overstimulating World by Sharon Heller.

This book has lots of information about sensory overload and sensory integration problems, but left me confused about the extent to which I have the problems that the book describes and whether there are good solutions.

The book mostly focuses on problems of being overwhelmed by sensory input, but also says sensory numbness can be associated with the same kind of problems. Some of the symptoms discussed describe me rather well, but a majority do not. The book seems to suggest that almost any nonstandard reaction to stimuli might mean a person is sensory defensive, which makes me wonder whether many unrelated conditions have been lumped into one category.

Many reviewers seem pleased that the book tells them they’re not alone in the problems that they’re facing. But I kept having conflicting impressions about whether the people described in the book are like me.

The book lists many possible solutions to sensory problems, which are described as making up a “sensory diet” – more suggestions than the author could plausibly understand well enough to know whether they work. Many are supported by anecdotal evidence, some by evidence that appears to be moderately good science, and for some the evidence seems inconclusive. I believe that they are better than random guesses, but I don’t expect to get much out of them without a good deal of trial and error.

Auditory integration training sounds like the kind of help I’m looking for, and the book makes that and some similar programs sound promising. But the Wikipedia entry on AIT is rather discouraging, and the Wikipedia entry on Sensory integration therapy isn’t very encouraging.

The book reports some interesting claims about the benefits of natural full-spectrum light, such as a large decrease in cavities (see “The effects of lights of different spectra on caries incidence in the golden hamster” by I. M. Sharon, R. P. Feller, S. W. Burney). But how much of this becomes unimportant when we take vitamin D supplements?

I just tried a full-spectrum light (OttLite 15ED12R 15w) recommended by the book. It provides more illumination with 15 watts than the 20 watt fluorescent bulb I normally use, and it was immediately obvious that the book I was reading looked better because it was whiter. But it has a distracting hum. Shouldn’t a book like this be able to warn me of this drawback?

There isn’t a lot out there on the subject of sensory integration, and educated guesses are better than nothing.

Assorted Links

Book review: Going Inside: A Tour Round a Single Moment of Consciousness, by John McCrone.

This book improved my understanding of how various parts of the brain interact, and of how long it takes the brain to process and react to sensory data. But there were many times when I wondered whether it was worth finishing, and I wish I had given up before the last few chapters that focused on consciousness other than neuroscience.

Too much of the book is devoted to attacking naive versions of reductionism and computational models of the brain. His claim that “chaos theory electrified science” is wrong. It electrified some reports about science, but has done little to create better models or testable predictions.

It’s misleading for him to claim the difference between human and animal consciousness “is terribly simple. Animals are locked into the present tense.” There are many hints that animals have some thoughts about the future and past, and it’s hard enough to evaluate those thoughts that we need to be cautious about denying that they think like us. He suggests that language and grammar provide unique abilities to think about the future. But I’m fairly sure I can analyze the future without using language, using mostly visual processing to plan a route I’m going to kayak through some rapids, or to imagine an opponent’s next chess move. I expect animals have some abilities along those lines. Human language must provide some improved ability to think about the future, but I find it hard to specify those abilities.

Book review: Sex at Dawn: The Prehistoric Origins of Modern Sexuality by Christopher Ryan and Cacilda Jetha.

This book makes a strong case that pre-agricultural humans were very far from monogamous, much like Chimps and Bonobos. It’s often convincing, but sometimes biased by ideology.

Some of the evidence comes from the difficulty that humans have being monogamous now, and the under-reported satisfaction of cultures that encourage egalitarian sharing of mates (including WWII pilots). Some stronger evidence comes from the size of our genitalia, and the promiscuous, egalitarian sex and reported absence of rape and war in our closest living relatives (Bonobos – have they really been observed well enough that we should expect to have seen rape and war?).

The book is highly critical of the Victorian version of marriage, but is somewhat approving of marriage as an institution if it’s more like some non-English cultures where occasional sex outside of the marriage is considered to be fairly harmless.

They also claim there was little violence, because food was abundant and it was normally easier to move to unoccupied land than to fight over resources. They provide decent reasons not to trust arguments that supposedly demonstrate high levels of violence in primitive cultures, but they don’t convince me they’re any more objective than the people they criticize. The most questionable part of this section is their belief that the natural growth rate of pre-agricultural humans was unusually low. They have some plausible reasons for expecting a slower population growth rate than the 25 year doubling time that Malthus expected in the absence of resource constraints, but they don’t come close to providing a good argument that Malthus was off by the factor of 10,000 that would be needed to reconcile the estimated pre-agricultural population growth rates with an absence of resource constraints. I get the impression that they imagine our direct ancestors had no competition from other hominids.

The book’s back flap claims that it contains an explanation of why homosexuality hasn’t been selected out of our genes, but the closest to that I could find in the book was a theory involving bonding which would explain bisexuality but not homosexuality.

Doctors are more willing to prescribe Viagra than cognitive enhancement drugs.


The report wonders whether it’s due to conservative tendencies among doctors. But Viagra and Modafinil both became available in the U.S. in 1998. Conservatism doesn’t explain why doctors are slower to accept Modafinil than Viagra. Although maybe combined with more patients asking for Viagra it would be plausible.

Concern over side effects might explain why doctors are less comfortable with Ritalin, but not why three different cognitive enhancing drugs all produced similar comfort levels – about half that of Viagra. And I see no signs that Modafinil is much riskier than Viagra.

Could it be concern that Viagra has an equalizing effect (making people more normal), whereas cognitive enhancers make people who can afford them smarter than the less fortunate? Partly – doctors were more willing to prescribe cognitive enhancers for older patients than younger ones. But the cross-drug comparisons were done for a case where “the patient was a 40-year-old reporting symptoms consistent with the label indications for the respective drug”. I’m pretty sure the label indications describe a patient who is functioning well below normal.

The obvious conclusion part of what’s happening is that doctors believe sex produces larger benefits than cognitive enhancement. If we ignore potentially important externalities such as sexually transmitted diseases versus improved science/technology (would doctors admit to doing that?), I could make a decent case for sex being more valuable. There’s no shortage of evidence that sex makes people happy, whereas there seems to be little or no correlation between cognitive ability and happiness.


Book review: Counterclockwise: Mindful Health and the Power of Possibility, by Ellen J. Langer.

This book presents ideas about how attitudes and beliefs can alter our health and physical abilities.

The book’s name comes from a 1979 study that the author performed that made nursing home residents act and look younger by putting them in an environment that reminded them of earlier days and by treating them as capable of doing more than most expected they could do.

One odd comment she makes is the there were no known measures of aging other than chronological age at the time of the 1979 study. She goes on to imply that little has changed since then – but it took me little effort to find info about a 1991 book Biomarkers which made a serious attempt at filling this void.

She disputes claims such as those popularized by Atul Gawande that teaching doctors to act more like machines (following checklists) will improve medical practice. She’s concerned that reducing the diversity of medical opinions will reduce our ability to benefit from getting a second opinion that could detect a mistake in the original diagnosis, and cites evidence that North Carolina residents have an unusually high tendency to seek second opinions, and also have signs of better health. But this only tells me that with little use of checklists, getting a second opinion is valuable. That doesn’t say much about whether adopting a culture of using checklists is better than adopting a culture of seeking second opinions. The North Carolina evidence doesn’t suggest a large enough health benefit to provide much competition with the evidence for checklists.

One surprising report is that cultures with positive views of aging seem to produce older people who have better memory than other cultures. It’s not clear what the causal mechanism is, but with the evidence coming from groups as different as mainland Chinese and deaf Americans, it seems likely that the beliefs cause the better memory rather than the better memory causing the beliefs.

Two interesting quotes from the book:

certainty is a cruel mindset

to tell us we’re “terminal” may be a self-fulfilling prophecy. There are no records of how often doctors have been correct or not after making this prediction.

Research indicates that cultures in which relationships can be formed and dissolved relatively easily produce more disclosure of intimate information between friends, probably due to a combination of greater need to invest in each relationship and lesser harm from taking risks that alter relationships.

The study compared Japanese culture to U.S. culture, but my impression is that there has also been a significant change over time in the U.S., with internet access increasing relationship mobility, followed by an increase in self-disclosure. (It’s possible that my impression was due to my move from New England to Silicon Valley in 1994 – there’s more social mobility in Silicon Valley, but I didn’t notice much change in self-disclosure until several years later).

It seems likely that the effects of the web on relationship mobility and self-disclosure will grow larger. The trend of increasing mobility has shown few signs of slowing, and the effects on self-disclosure probably lag by at least a few years.

Book review: Leadership and Self-Deception: Getting out of the Box, by the Arbinger Institute.

In spite of being marketed as mainly for corporate executives, this book’s advice is important for most interactions between people. Executives have more to gain from it, but I suspect they’re somewhat less willing to believe it.

I had already learned a lot about self-deception before reading this, but this book clarifies how to recognize and correct common instances in which I’m tempted to deceive myself. More importantly, it provides a way to explain self-deception to a number of people. I had previously despaired of explaining my understanding of self-deception to people who hadn’t already sought out the ideas I’d found. Now I can point people to this book. But I still can’t summarize it in a way that would change many people’s minds.

It’s written mostly as a novel, which makes it very readable without sacrificing much substance.

Some of the books descriptions don’t sound completely right to me. They describe people as acting “inside the box” or “outside the box” with respect to another person (not the same as the standard meaning of “thinking outside the box”) as if people normally did one or the other, we I think I often act somewhere in between those two modes. Also, the term “self-betrayal”, which I’d describe as acting selfishly and rationalizing the act as selfless, should not be portrayed as if the selfishness automatically causes self-deception. If people felt a little freer to admit that they act selfishly, they’d be less tempted to deceive themselves about their motives.

The book seems a bit too rosy about the benefits of following it’s advice. For instance, the book leaves the reader to imagine that Semmelweis benefited from admitting that he had been killing patients. Other accounts of Semmelweis suggest that he suffered, and the doctors who remained in denial prospered. Maybe he would have done much better if he had understood this book and been able to adopt its style. But it’s important to remember that self-deception isn’t an accident. It happens because it has sometimes worked.