Bayesian Investor Blog

Book review: Into the Gray Zone: A Neuroscientist Explores the Border Between Life and Death, by Adrian Owen.

Too many books and talks have gratuitous displays of fMRIs and neuroscience. At last, here’s a book where fMRIs are used with fairly good reason, and neuroscience is explained only when that’s appropriate.

Owen provides evidence of near-normal brain activity in a modest fraction of people who had been classified as being in a persistent vegetative state. They are capable of answering yes or no to most questions, and show signs of understanding the plots of movies.

Owen believes this evidence is enough to say they’re conscious. I suspect he’s mostly right about that, and that they do experience much of the brain function that is typically associated with consciousness. Owen doesn’t have any special insights into what we mean by the word consciousness. He mostly just investigates how to distinguish between near-normal mental activity and seriously impaired mental activity.

So what were neurologists previously using to classify people as vegetative? As far as I can tell, they were diagnosing based on a lack of motor responses, even though they were aware of an alternate diagnosis, total locked-in syndrome, with identical symptoms. Locked-in syndrome and persistent vegetative state were both coined (in part) by the same person (but I’m unclear who coined the term total locked-in syndrome).

My guess is that the diagnoses have been influenced by a need for certainty. (whose need? family members? doctors? It’s not obvious).

The book has a bunch of mostly unremarkable comments about ethics. But I was impressed by Owen’s observation that people misjudge whether they’d want to die if they end up in a locked-in state. So how likely is it they’ll mispredict what they’d want in other similar conditions? I should have deduced this from the book stumbling on happiness, but I failed to think about it.

I’m a bit disturbed by Owen’s claim that late-stage Alzheimer’s patients have no sense of self. He doesn’t cite evidence for this conclusion, and his research should hint to him that it would be quite hard to get good evidence on this subject.

Most books written by scientists who made interesting discoveries attribute the author’s success to their competence. This book provides clear evidence for the accidental nature of at least some science. Owen could easily have gotten no signs of consciousness from the first few patients he scanned. Given the effort needed for the scans, I can imagine that that would have resulted in a mistaken consensus of experts that vegetative states were being diagnosed correctly.