Science in Action: Omega-3 (time course)

During a recent trip to Los Angeles, I continued my self-experimental activities — three mental tests, which I did once/day. On the last day of the trip, my scores were much better than usual. There was an obvious explanation: I had taken my daily flaxseed oil (4 T) closer to the time of the test — 4 hours before rather than 12 hours before. This suggested that flaxseed oil has an effect that happens fast and diminishes quickly. Earlier observations had implied that the effect at least a few days to wear off completely.

Back home, I wanted to measure this effect. I started testing more often. With a two-answer (yes-no) test, I saw the short-lived effect a few times. But accuracy was relatively low (about 90% correct) due to anticipation errors. I switched to a new test that measures how fast I count letters.

After doing the new test about 70 times, my performance was fairly constant. I resumed trying to measure the short-lived effect. At 3 pm six days ago I drank 4 tablespoons of flaxseed oil. Here are the results:
time course of flaxseed-oil effect
The blue line shows when I took the flaxseed oil. Within a few hours, reaction time sharply decreased. The improvement slowly went away.

Two big conclusions: (1) Here is a new way to see the effect of flaxseed oil. My earlier experiments took a few weeks; this took a few days. (2) Low between-test variability. The cluster of points around the time of the first meal is an example. The one point below the cluster is a counter-example — I have no idea why it was low all of a sudden. But that is rare. Almost always erratic points suggest explanations. During the second meal I drank a sugar-sweetened drink, forgetting previous observations that these drinks lower reaction time for a few hours (no doubt because they increase blood glucose levels).

This experiment has one big flaw, which is that after I took the flaxseed oil I started making more frequent measurements. A year ago, I made the same mistake with my balance experiments. There is a kind of Heisenberg Uncertainty Principle here: The measurement itself — the test — causes learning. Learning lowers the baseline.

I’ll fix this mistake and a few others and do the experiment again.