From my omega-3 results I got the idea that our brains may work better or worse without our noticing. I want to track how well my brain works not only to test the effects of different dietary fats (our brain is more than half fat) but also to allow the possibility of discovering new effects, both good and bad.

One test I am using is a typing test (early results here). Another is an arithmetic test. I got the idea of using arithmetic from Tim Lundeen. Like him, I found that the speed with which I could do simple arithmetic problems (8+0, 4*3) was sensitive to the amount of omega-3 in my diet.

The arithmetic test involves doing 100 problems separated into 5 blocks of 20 each. There is little time between each problem. I type the last digit in the answer; e.g., if I see 8*8 I type 4. The possible answers are 1, 2, 3, 4, 7, 8, 9, and 0 so that I don’t have to move my fingers off the keys. There is feedback after each block. I aim for 95% correct.

This is my second use of an arithmetic test. The advantages of this one compared to several other tasks I have tried are:

• Portable. Only requires a laptop.
• Well-learned. So I should plateau (reach a steady speed) sooner than with a task I learn from scratch. When my speed is steady it will be easier to compare different conditions — no need to correct for learning.
• Uses eight fingers. Many tasks used by experimental psychologists have just two possible answers (yes/no). With eight possible answers there is less anticipation and less worry about repetitive strain injury.
• No data entry. The task is written in R, the language I use to analyze the data.
• Many measurements per minute. This allows me to correct for problem difficulty and get a standard error for each test session.

Here are early results.

In the test sessions after January 1, two sets of points are above the line — I was slower than expected, in other words. Both came from test sessions about an hour or so after I woke up. At the time of those sessions I felt fine — not tired, not groggy — and was a little surprised. This is a trivial example of what I am looking for: new environmental effects.

The bigger context of this research is that scientists know a lot about idea testing but almost nothing about idea generation — how to find new ideas worth testing. Maybe this research will teach me something about idea generation.

A talk by Tim Lundeen about related stuff.

I am developing tests to measure how well my brain is working. Brief tests I can use daily. My experiences with flaxseed oil make me suspect that sometimes our brains work better and/or worse than usual for many hours or days at a time and this goes unnoticed. If these instances of better or worse function could be detected, maybe we could figure out their causes — and thereby improve how well our brains work by getting less bad stuff and more good stuff. In the case of flaxseed oil, I noticed that one morning my balance was much better than usual. I noticed this only because I was doing something unusual: putting on my shoes standing on one foot. I verified that observation with a better test of balance and later found that flaxseed oil improved my performance on several mental tests, such as speeded arithmetic.

One test I am using is a typing test: On each trial I type a random sequence of six letters four times. For example, if the sequence is “rksocn” I would type rksocnrksocnrksocnrksocn”. At the moment the measure of performance is how fast I type the 24-letter sequence. Each session consists of ten trials.

Here are the results so far:

Each point is a mean over the ten trials; the error bars show standard errors. I was glad to see there was little sign of learning after the first few sessions. Having to correct for learning would make comparison of different days more difficult.

Because I am collecting a lot of data, I could look at these data more carefully. It took me a little while to do an analysis where I corrected for the difficulty of each string: Some will be easier to type than others. My first attempt at correction involved adding a factor for each letter: does the string contain an “a” (factor 1)? Does the string contain a “b” (factor 2)? And so on. This correction made a big difference: The residual mean square was almost cut in half (= sensitivity was doubled). After correcting for this, I got new estimates and standard errors for each test session:

Uh-oh! The new analysis revealed there had been something unusual about the second-to-last test session — my typing had been distinctly slower than usual. Something I ate? Unfortunately, by the time I did this analysis I could no longer remember what might have been different.

This article says that a fat-digesting enzyme called lipase becomes inactive while sitting. The evidence, seen in the accompanying video, is extraordinary: a cloudy vial of blood (taken after a sitting meal) versus a much clearer vial of blood (taken from the same person after a standing meal.)

I found that a great increase in standing, lasting years, had no effect on my weight but I slept much better. I ate standing up much more often.