Seth’s blog

Recently I visited some friends whom I hadn’t seen for a while. You’re more talkative, they said. I attribute this to flaxseed oil.

I became interested in the effects of flaxseed oil partly because of the aquatic ape hypothesis, the idea that living near water had a big effect on human evolution. During a long period of human prehistory, the theory says, we swam a lot, presumably to catch fish. If we ate lots of fish (high in omega-3) at the same time our brains grew large, it was quite possible that our brains need large amounts of omega-3 to function properly. Flaxseed oil is high in omega-3.

Elaine Morgan, the theory’s main proponent, has written several books about it, “each more po-faced [= academically correct] than the last,” she has said. I have finally read two of them and was pleased to find more scrutiny made the theory more plausible.

Background to the idea that humans were once aquatic is that several mammals have obviously become aquatic — starting on land they shifted to water. Sea lions, whales, and so on. Birds have become aquatic — for example, ducks. Insects have become aquatic. Elephants appear to have become aquatic and then terrestrial again — note how well they can swim. There is ample precedent, in other words.

Humans differ in all sorts of anatomical and physiological ways from other primates and the aquatic ape theory has straightforward explanations for many of them:

1. Humans have subcutaneous fat, other primates don’t. Other aquatic mammals do. Explanation: The fat serves as insulation.

2. Humans have almost no fur, other primates do. Other aquatic mammals don’t. Explanation: Fur creates drag in the water. In the air, fur insulates.

3. Humans are bipedal. Explanation: Walking upright keeps the head out of the water, allowing breathing.

The results I described in the previous post surprised me because (a) my performance suddenly got better after being stable for many tests and (b) after the improvement, further practice appeared to make my performance worse. I’d never before seen either result in a motor learning situation. If you can think of an explanation of the result that practice makes performance worse, and animal learning isn’t your research area, please let me know.

Learning researchers used to think of associative learning as a kind of stamping-in process. The more you experience A and B together, the stronger the association between them. Simple as that. In the 1960s, however, several results called this idea into question. Situations that should have caused learning did not. The feature that united the various results was that in each case, learning didn’t happen when the animal already expected the second event. If A and B occur together, and you already expect B, there is no learning. Theories that explained these findings — the Rescorla-Wagner model is the best known, but the Pearce-Hall model is the one that appears to be correct — took the discrepancy between expected and observed — an event’s “surprise factor” — rather than simply the event itself, to be what causes learning. We are constantly trying to predict the future; only when we fail do we learn.

In my motor-learning task, imagine that the brain “expects” a certain accuracy. When actual accuracy is less, performance improves. Performance stops improving when actual accuracy equals expected accuracy. The effect of more omega-3 in the blood, and therefore the brain, was to increase expected accuracy. (One of the main things the brain does is learn. If we do something that improves brain performance in other ways, it is plausible that it will also improve learning ability.) Thus the sudden improvement. The decrement in accuracy with further practice came about because, when the omega-3 concentration went down, actual accuracy was better than expected accuracy. Accuracy was “over-predicted,” a learning theorist might say. So the observed change in performance was in the opposite-from-usual direction. Accuracy got worse, not better.

Related happiness research. “Christensen’s study was called “Why Danes Are Smug,” and essentially his answer was it’s because they’re so glum and get happy when things turn out not quite as badly as they expected.”

The more I played racquetball, the more accurate my shots became — the more control I had. It was a kind of learning: learning to place the ball. I was fascinated by how little we knew about how that learning took place. I studied associative learning in my own research. The motor learning during racquetball resembled associative learning in the sense that my actions (hitting the ball with the racket) were shaped by what happened next (accuracy of placement). Yet I knew nothing non-obvious about motor learning.

This background of ignorance is why I find my latest flaxseed oil results so interesting. As I’ve posted, I’ve started using a new test in which I use the touchpad to “toss” the cursor from one spot to another (that is, move the cursor with a single finger movement), and measure how close it “lands” to the target. The function relating cursor position to finger position on the touchpad isn’t simple.

Of course I wanted to see how flaxseed oil affected performance on this task. I doubted that it would. This task is untimed. No time pressure. It is like shooting free throws. Most of the previous tasks I’ve used that have shown a flaxseed-oil effect have been tasks where you respond as fast as possible. My balance test was go at your own pace, but it involved a huge amount of computation. Balancing my body on one foot for several seconds seemed to involve a lot more computation than moving a finger about an inch.

Usually I take 4 tablespoons of flaxseed oil just before bedtime. One recent day I took it much earlier and did the toss test at 30-minute intervals before and for several hours afterward.

Here are the results plotted as a function of test session number.

Here are the same results plotted versus the time of the test:

Here is a close-up of the crucial data:

About two hours after I drank the flaxseed oil, my accuracy got worse. Then it slowly got much better. The amazing thing about the improvement is that it reached a maximum long after you would think that the effects of the flaxseed oil had worn off. My overall level of omega-3 is high because I take 4 T flaxseed oil per day. The effect of shifting when I drink the 4 T is just to change the timing of a short-lived peak. Usually that peak happens when I’m asleep and my omega-3 levels are reasonably constant while I’m doing the test. In this case the peak happened while I was doing the test.

I’ll discuss what this might mean in a later post.

Drug addiction, sure. The first pleasurable drugs were probably discovered hundreds of thousands of years ago, if not much earlier. All cultures use drugs. Drugs physically reach the brain. But video game addiction? Video games are a millisecond old, compared to drugs. How did they get so potent so fast?

Self-experimentation made me ask. Using an ordinary psychological test and a speeded arithmetic task, I discovered a fast-acting effect of flaxseed oil. About two hours after ingestion of 4 tablespoons, my brain worked detectably better. The effect wore off over several hours. To properly study this effect, and exploit it to learn more about what fats we should eat (which has been very hard to figure out), I would have to test myself many times per day for many days. Thousands of tests. It would be a lot easier if the tests were fast, portable, and fun — especially fun. Many computer games have these traits. But they don’t provide the data I need, which is a measure of how well my brain is working, and they take too long.

After talking with Greg Niemeyer, I came up with four properties, shared by many games, that might be why they are fun: 1. Right difficulty level. Neither too easy nor too hard. This is a variable emphasized by Mihaly Csikszentmihalyi in Flow. 2. Feedback. You learn how well you are doing. 3. Variety. Not the same thing over and over. 4. Color. I constructed a task with all four features. To my dismay, it wasn’t fun! (So much for the placebo effect.) I had to force myself to do it.

I had no idea what was wrong. Then, as I’ve written, a friend gave me a bilboquet, which led me to think that there were two principles of fun-making I’d left out: 1. Hand-eye coordination. We enjoy tasks that involve this. 2. Completion. We enjoy tasks where something is cleared up or put neatly together.

I used these ideas to construct a new test. It consisted of moving the cursor around the screen from one colored circle to the next. I move the cursor to a circle and click on it. That circle disappears and a new circle appears somewhere else. It’s a bit like shooting one circle after another. Aim, click, aim, click. Each circle is effectively a new trial. The speed at which I moved the cursor to the new circle and click on it is the main measure. There is trial-by-trial feedback: the color of the next circle depends on how quickly I got to the last circle. Here’s a screen shot (cursor not shown):

I did this on a Thinkpad. I used the trackpoint to move the cursor. This had the pleasant feature that there was no obvious learning curve — I didn’t improve with practice. Presumably because I have years of practice with the trackpoint

Eventually I got around to the big question: Was this test sensitive to the effects of flaxseed oil? I’ve done two series of measurements to answer this. Here are the results from the first series:

The green line shows when I drank 4 tablespoons of flaxseed oil (without lignans). Here are the results from the second series:

Again, the green line shows when I drank 4 tablespoons of flaxseed oil.

Both times the results resembled my previous results. The flaxseed oil appeared to cause a decrease (= improvement), which reached a maximum around 2 hours after ingestion and declined. The results were far from beautiful but because of the similarity to earlier results (here, here, and here) I found them fairly persuasive. They certainly suggest doing more with this test.

Then I made a different game…

My visit to Greg’s class.

Anonymous writes again:

I got caught in a nasty achilles lock the other day–it’s an MMA [mixed martial art] submission move–and while trying to escape, I accidentally dislocated my fibula at the knee. It made a LOUD popping noise, to the point where everyone in the gym stopped. It popped it back in immediately, and other than some instability, it felt OK. Thankfully there was a doctor there (by chance–he does MMA and was in my class). He spent like 15 minutes examining my knee and said that other than some stretched ligaments, it was fine. His quote (I’m paraphrasing):

“That’s amazing. You should need reconstructive surgery right now. I don’t know how that happened, you must have rubber ligaments.”

I told him about taking 4 tablespoons of flax seed oil every day, and he was shocked, and said he was going to research it to see if that could be why I got so lucky. Told him to Google you, it’s all there.

The injury happened Friday. Today (Tuesday) the doctor looked at my knee again in class, and he was amazed not only at the lack of swelling, but that I was able to roll today (not full speed, just lightly).

I have played sports my whole life and have had at least half a dozen various knee injuries. Things like minor cartilage tears, hyperextensions, strains, etc.–none that were this major (a dislocation of a bone at the joint). Of those injuries, I was out longer and recovered much slower than I have with this one. I know this isn’t proof of anything, and I don’t know how much the flaxseed oil has had to do with what happened, but even the doctor is shocked.

More about omega-3 and sports injuries here and here and here.

Addendum. He uses Whole Foods flaxseed oil without lignans.