Can someone really know what it’s like to have a stroke? A skeptic considers Jill Bolte Taylor’s “Stroke of Insight.”

There’s a TED video making the rounds to some high acclaim these days. The video features Jill Bolte Taylor giving a video presentation entitled “My stroke of insight.”

Here it is in a nutshell. Bolte Taylor is a neuroanatomist who suffered a stroke in 1996. She has recovered quite well from a serious challenge, as you can see from the embedded video. Her topic is one that fascinated me, and I watched her video with undivided attention. If you decide to watch this video, you might also be especially interested in her description of the struggles that she faced at the moments during which she was actually having her stroke. She describes experiencing the successive losses of her abilities to interpret visual and auditory input. Written words began to look like meaningless scribbles. Things became even more surreal when she “realized” that she couldn’t understand simple conversations.

It pains me to write what I am about to write , because I really want to believe that Bolte Taylor is accurately portraying real-life events. What she is describing is fascinating and her narrative is gripping. I am relieved to know that she has made a fantastic recovery and I admire her for stepping into the public eye in an attempt to provide a unique personal perspective regarding strokes. I have serious doubts about her narrative, however. I am concerned that Bolte Taylor is confabulating. I have several reasons for suggesting this.

The first thing I noticed was Bolte Taylor’s absolute lack of doubt or hesitancy regarding any of the claims she is making. Her story sounds too well rehearsed and her presentation appears to be too much like an acting performance. Can the human mind accurately process, remember and then describe the experience of a stroke? This is highly debatable among reputable scientists. People are prone to all kinds of perceptual and memory distortions during illnesses, even illnesses that are much milder than strokes. For instance, I recently had an experience where I fainted for a couple seconds when I was sitting a few feet from a doctor. He is certain that I fainted (briefly) based upon what he saw. I have no recollection of losing any consciousness at all, however. I have no reason to doubt my doctor, because he was there and he attended to me when he saw me slipping away. I trust his observations more than my own, because my mind was in the process of shutting down at the critical moment. Even though I fainted, I would be an accurate witness only to the events leading up to fainting, not to the act of fainting itself.

I’m not suggesting that Bolte Taylor was unconconsious. But even when people are fully conscious and not suffering massive strokes, there are severe limitations to using instrospection. It is highly unreliable in many cases of self-diagnosis.

Memory is highly prone to distortions. Remembering something is not at all like hitting the play button on a tape recorder. There are thousands of studies demonstrating this fallibility of human memory. Some of these studies concerns flashbulb memories, where people who were certain that they knew the details of where they were and who they were with during major tragic events, turn out to be quite mistaken regarding many of those basic details. When there are extraneous reasons to believe (including, potentially, the attention one might receive by touring from place to place to give a talk that is well received by gentle audiences) the risk of confabulation is even greater.

We all have heard claims of of patients that they started floating down tunnels with a glowing light in the distance. Many of these people interpret this phenomenon as a journey down a path toward heaven or Jesus.

The people who relate these stories of floating down tunnels are sincere. They aren’t trying to fool us. They believe what they are saying. Similarly, I believe that Bolte Taylor believes what she is telling her audience. Believing what you are saying does not necessarily make what you are saying true, however. Nor does suffering a stroke necessarily make you a credible witness as to what it was like to have a stroke. Whether you are a credible witness depends upon whether you were brain was capable of accurately observing and remembering what was occurring while you’re brain was also in the process of severe biological breakdown.

What is confabulation? Most importantly, it is not lying. There is no intent to deceive anyone. On the other hand, all of us have the tendency to fill in gaps where our memory is not sharp. That is the point of an article called “Mind fiction: Why your brain tells tall tales,” from New Scientist:

It isn’t fibbing, as there is no intent to deceive and people seem to believe what they are saying. Until fairly recently it was seen simply as a neurological deficiency – a sign of something gone wrong. Now, however, it has become apparent that healthy people confabulate too.

We may all do it routinely. Children need little encouragement to make up stories when asked to talk about something they know little about. Adults, too, can be persuaded to confabulate, as Timothy Wilson of the University of Virginia in Charlottesville and his colleague Richard Nisbett have shown. They laid out a display of four identical items of clothing and asked people to pick which they thought was the best quality. It is known that people tend to subconsciously prefer the rightmost object in a sequence if given no other choice criteria, and sure enough about four out of five participants did favour the garment on the right. Yet when asked why they made the choice they did, nobody gave position as a reason. It was always about the fineness of the weave, richer colour or superior texture. This suggests that while we may make our decisions subconsciously, we rationalise them in our consciousness, and the way we do so may be pure fiction, or confabulation.

Here’s another reason I don’t trust Bolte Taylor’s account of her stroke. Although she claims impressive academic credentials, she doesn’t talk like a disciplined cognitive scientist. She stirs vague non-scientific terms into her talk only after attempting to firmly establish her credibility with the cachet of science. She grossly oversimplifies the lateralization of the brain in ways that all reputable cognitive scientists would resist (I’m not doubting compelling evidence exhibiting lateralization). In the words of this Wikipedia article on lateralization, Bolte Taylor speaks to us as a popular psychologist rather than as a measured and disciplined neuroscientist:

Popular psychology tends to make broad and sometimes pseudoscientific generalizations about certain functions (e.g. logic, creativity) being lateral, that is, located in either the right or the left side of the brain. Researchers often criticise popular psychology for this, because the popular lateralizations often are distributed across both hemispheres.

She doesn’t stop at lateralization, either. She employs flowery ideas that you’d never hear from anyone trying to be faithful to the experimental literature on neuroscience. Things aren’t as simple as Bolte Taylor portrays them to be, and it was annoying to me to see and hear her fearlessly marching forward with her sweeping claims (of what it is to be a “left brained person” for instance). In the end, I was annoyed with Bolte Taylor, despite her passionate way of speaking and her obvious talent for drawing us into her story.

You’ll find that many people on the Internet absolutely love Bolte Taylor. They find her to be inspirational. These people, however, are no more self-critical than Bolte Taylor is herself. You’ll see this yourself when you read their comments and see the cheerleader-type praise they heap upon Bolte Taylor.

It is thus with some trepidation that I write this post at all. I don’t want to rain on Bolte Taylor’s parade. On the other hand, my skepticism has never been aimed only at religious claims or claims regarding the paranormal. I am equally skeptical of many of the claims made by ordinary and well-motivated people.

I am not alone in my concern about Bolte Taylor’s presentation. A post at Mindhacks expresses some of the same concerns:

It’s a bit poetic in places. You can almost hear the sound of a thousand cognitive scientists gritting their teeth as she describes the supposed functions of each cerebral hemisphere and probably the sound of some of them fainting when she describes the “deep inner peace circuitry” of the right hemisphere.

Much of what Bolte Taylor has to say about the experience of having a stroke makes perfect sense. My concern is whether she was actually “there” to witness what happened to her. Whether or not she was “there,” she certainly tells a good story about what it might be like to have a stroke.

1. Garrison Keillor describes his stroke
2. Christians put on their Skeptic Hats to deal with the “Tomb of Jesus”
3. James Taylor’s “Covers”: Live studio recording with the entire band.
4. Bush tells us he is “winning the war on terrorism.” I wonder what he considers losing.
5. How well do old brains work?

Tags: accurate, Bolte Taylor, confabulation, distortion, memory, self-critical, stroke, TED

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