I'm continuing to read and enjoy Andy Clark's The Experience Machine: How Our Minds Predict and Shape Reality. It's one of the best books about modern neuroscience that I've ever read, and believe me, I've read a lot of them.
My first post about the book laid a foundation for these subsequent posts, as I get deeper into The Experience Machine. This is a one sentence summary of the Big Idea discussed in the book -- which makes a heck of a lot of sense.
Predictions and prediction errors are increasingly recognized as the core currency of the human brain, and it is in their shifting balances that all human experience takes shape.
In a "Psychiatry and Neurology" chapter, Clark talks about prediction errors. Those are the difference between what the brain expects to perceive, given sensory inputs and prior experience, versus what is actually perceived.
Ideally those errors are reduced as we learn more about the slice of reality we're attending to.
But sometimes they aren't, which can create problems for us, big or small. Here's how Clark explains this. It won't be completely understandable, since I'm just sharing small excerpts from his book, but you should get the gist of his message.
Varying estimates of precision alter patterns of post-synaptic influence and so determine what (right here, right now) to rely on and what to ignore. This is also the way brains balance the influence of sensory evidence against predictions.
In other words, precision variations control which bits of what we know and what we sense will be most influential, moment by moment, in bringing about further processing and actions. Expressed like that, the intimacy of precision and attention is apparent.
Precision variation is what attention (a useful but somewhat nebulous concept) really is.
For example, suppose I want to find a needle recently dropped in a bed of hay. According to predictive processing, my brain ups the precision-weighting on specific aspects of the visual information that would indicate a small silvery object, thereby increasing my chances of success.
That's what attention, if these accounts are correct, really is -- attention is the brain adjusting its precision-weightings as we go about our daily tasks, using knowledge and sensing to their best effect. By attending correctly, I become better able to spot and respond to whatever matters most for the task I am trying to perform.
Precision estimation is thus the heart and soul of flexible, fluid intelligence.
But what happens when precision estimations misfire? This would skew the impact of different bits of sensory evidence, and of different predictions. Precision estimation is the brain's way of telling itself where, and by how much, to place its bets.
When this goes wrong, our brains will bet badly; they will misestimate what to take seriously and what not to take seriously, thereby generating false or misleading experiences. This is exactly what seems to be happening with functional disorders. In these cases, unwilled misallocations of precision act as self-fulfilling prophecies.
Predictions of pain or impairment become highly overweighted, and those predictions overwhelm the actual sensory evidence, forcing experience to conform to our own hidden but misplaced expectations.
I found examples of this to be fascinating.
As I said in my first post about the book, it's going too far to say that this proves that we create our own reality. However, our brains definitely shape our experience of reality, sometimes in disturbing ways. "Functional" here means that there is a loss of function without evidence of systemic, or structural, damage of disease.
There is good evidence that misfiring precision assignments (unusual patterns of attention) play a role in many, perhaps all, functional neurological disorders. For example, simply distracting the sufferer by making them direct their attention elsewhere often makes functional (but not structural) tremors vanish.
...This creates a version of the famous "refrigerator light illusion." You might infer that your fridge light is constantly on just because the light is on every time you look inside. But actually it is the act of looking (opening the door) that turns on the light.
Similarly, you might believe you have a near-constant tremor because the tremor is always there when you pay attention to it. But if the tremor is actually in whole or in part the result of the process of "predicting and attending" itself, that assumption may be wildly wrong.
...Strongly anticipating pain, numbness, weakness, or other symptoms alters patterns of attention (precision-weightings) in ways that can either amplify or entirely generate the experience -- which then seems to confirm those very expectations.
...To make sense of these self-constructed feelings of pain, numbness, weakness, or paralysis, sufferers may start to suspect deep hidden causes -- such as persistent hidden illness. These new beliefs then further reinforce the expectations of those symptoms, reinforcing the cycles of aberrant attention.
...This is rather like the case of the performer with stage fright whose true abilities are masked by their own mounting expectations of failure. The circularity is daunting. Every new instance of stage fright confirms the expectations of failure, and those expectations ensure that the instances of failure accumulate.
Recognizing this circularity is, however, often the first step in breaking the cycle, as we'll see later when looking at ways to "hack" our own predictive brains.
For lots of people, pain is an unpleasant part of their daily life. Clark speaks about pain in this chapter.
Individuals will differ in how they assign precision to bodily signals, including those associated with pain and disability. Moreover, living with a condition for a long time enables idiosyncratic expectations (for example, about severity in different contexts) to arise and become ingrained.
This means that even where there is some standard structural cause such as a bulging or herniated disc in someone with back pain, the way we experience our symptoms may over time come to involve large doses of mindset and expectation.
In a certain sense, chronic pain at that point is perhaps best considered not so much as a symptom, but as the disease itself -- the very state that needed to be addressed.
...It shows us exactly why, as leading pain theorist Mick Thacker puts it, we need to move away from thinking of pain as a simple sensation, a direct signal of damage or potential damage, to a view of pain as a perception.
Like all perceptions, it takes shape only thanks to the precision-weighted interaction of predictions and current bodily signals. It is that process of combination that provides the wiggle room that enables persistent pain or impairment without damage, threat, or disease.
This is not to say that everything will respond to changes in expectations. It won't. But attention and expectation are key players in the construction of all our experiences of health and illness, and this is true even when standard structural causes (damage or disease) are present.
How we talk online is much different from how we talk in person
Next year I'll celebrate the 20th anniversary from when I started this blog in 2004. But, hey, I figure that I might as well spread out the festivities by making some observations from time to time about this here Church of the Churchless.
Like, right now.
The most important thing I want to say is gratitude. Over the years I've learned a great deal from the people who visit this blog and leave comments. Typepad, my blogging service, says there have been 70,198 comments on 3,390 posts.
So that's about 21 comments, on average, per post that I've written. I read most comments, though if I'm busy, I'll just take a glance at a comment, especially if it's a lengthy one.
Those comments are my blog's way of having a conversation -- with me, and with other blog visitors. I wish Typepad allowed for editing of comments by the people who share them, and that it was possible to organize the comments in a different fashion than in a chronological fashion.
But wishes aren't reality. Anyway, I deeply appreciate the time and effort people put into their comments, though obviously the quality varies from a high quality essay to random observations that make little sense.
Which is no different from the conversations all of us have in everyday life. But otherwise, there's big differences between how people communicate online versus in person.
Online, many choose to not use their real name. I can understand why in certain circumstances. For example, on this blog criticism of a religious leader, or the religion itself, can be problematic if someone uses their real name and is still involved with the organization they're criticizing.
That's why most people who write to me with an interesting story about their faith ask that I share it anonymously. The downside of anonymity, though, is that it enables people to say things in cyberspace that they'd be reluctant to say to someone face-to-face.
I'm definitely guilty of this myself at times. So if I'm directing a blog post or a comment at a specific person, I need to do better at visualizing that person standing in front of me as I say what I want to say about them.
Another problem with online conversations is that in ordinary life communication doesn't just involve words. It also involves a tone of voice, facial expressions, body language. And of course, an ability to say things like "I don't quite understand; please elaborate on what you meant when you said _______"
So its easy to misunderstand those with whom we interact online.
I like to express strong opinions. Many commenters on my blog posts also like to express strong opinions. So we’re going to feel misunderstood by other people at times. That comes with the territory of expressing strong opinions in a setting where only written words can be shared, not the other ways we use to communicate with people.
In a way it's surprising that comment conversations on this blog are as friendly and productive as they usually are, given how many obstacles there are to understanding another person in cyberspace.
But sometimes feelings get hurt. This is unfortunate, though often unavoidable. Partly it's due to different ways of communicating between men and women. I don't want to overemphasize this. It just seems like a reality to me.
I talked about this in a 2005 post on my HinesSight blog, "Why men don't share their feelings."
“How’re you doing?” says Dennis as I walk into the Pacific Martial Arts changing room. Instead of replying with my habitual robotic “Fine, how’re you?” I have a crazy impulse to actually tell him. I’ll share my feelings!
“Well, my feet have been tingling for about a week. I don’t know what’s going on. I’ve got an appointment to see a doctor tomorrow.” Without missing a beat (appropriately: Dennis is a drummer) I hear, “You’ve got a brain tumor. No doubt about it. You’re going to die.”
For the rest of our hour and a half training session, whenever I stop to check on how my feet are doing Dennis again says, “Oh yeah, you’ve got a brain tumor. Your time is up.”
Sensei Warren, our regular martial arts instructor, came in late. After telling him my tale of tingling feet I got a marginally better prognosis: “You’ve got diabetic neuropathy. No doubt about it. You’re going to lose your feet.” And I don’t even have diabetes.
Now, I know both Dennis and Warren care a lot about me. They demonstrated their manly concern by telling me that I’m either going to die or lose my feet. If one of them had given me a big hug and said “Don’t worry, everything is going to be all right,” I would have begun to worry that he had a brain tumor.
If I want sympathy, I’ll tell my troubles to my wife. From my marital arts buddies I get camaraderie and support that isn’t expressed in words. Dennis taught the class that evening. He started off by saying, “Let’s work on kicks tonight since your feet are giving you a problem.”
Which is what we did. For almost an hour. The unspoken message was, “Your feet are OK. Suck it up. This is no big deal.” That’s pretty much what the doctor said the next day: “Your feet look fine; I’ll do a blood test anyway; call me in a month if you’re not better.”
I'm sharing this anecdote because it points to a seeming fact: men are more comfortable with the rough-and-tumble of online communications because they're more used to joking around with each other in some rough ways.
This is fine.
But I worry when a woman shares something on this blog, then gets attacked in an intense fashion. Mostly or entirely by men. That's when I feel protective toward the woman, since I feel responsible for providing a safe space for people to share their ideas without feeling like they're in some sort of danger.
Well, those are my thoughts for tonight. Thanks for listening. I'll get back to a regular Church of the Churchless blog post soon.
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