I used to play a trick on myself where I'd hold a particular hand position and meditate on a state of mind, one intended to clear my mind and get centered, the other to get me amped up to go do some work. (I worked in construction at the time) It worked amazingly well, and I spent several weeks / months feeling no other emotions. I'd feel the state slipping, and just hold the hand position and the state would come back. Only reason I stopped was that the emotional monotony got old after awhile.

I have no trouble believing that fish oil as a mood stabilizer can work fantastically, and yet have no physiological effect whatsoever.

You can look at double blind trials of the effects of fish oil as a mood stabilizer. Its possible that the GP's wife has an idiosyncratic lack of reaction and is just fooling herself but that would be pretty improbably so I'd say her beliefs are well justified. The observed effects aren't small, we're talking about things like reducing assaults in prison by 1/3.

http://bjp.rcpsych.org/content/bjprcpsych/181/1/22.full.pdf

This is interesting, but 1) it does not test the effects of fish oil as a mood stabilizer and 2) there is something sketchy about the way the data are reported.

1) It is a study of vitamin, mineral and essential oil supplements. There is no basis for ascribing any measured effect to essential oils as such.

2) In a number-rich report, it's odd that they don't report either the number or distribution of incidents in any detail, and I can't make their averages work out.

For example, they have 172 people in the study for an average of 142 days, and they talk about numbers like 11 and 16 incidents per thousand person-days, which would lead one to predict around 170x140x(11 to 16)/1000 ~ 250 - 300 incidents, but they then go on to talk about studying 754 Governor and minor reports, or 338 Governor reports and 416 minor reports (in all cases the reports appear to cover the full study population, which is the majority of the prison population).

One can conclude from this that most of the incidents in the prison are due to the people who weren't in the study, maybe? I don't know, but there's something odd going on.

Furthermore, they don't given any idea of individual variation within the population. The conclusion you'd draw if most of the incidents are associated with a few individuals vs spread out across the population might not be the same. Were all individuals pretty much similar in their response, or was the effect localized to some? The results as reported are consistent with a few problematic individuals becoming peaceful and everyone else getting slightly worse.

When making an argument that an intervention is good for a population, you really have to dig into the support for the claim across the population, not report averages as if they could only arise one way.

So while this is intriguing an interesting, it isn't as strongly convincing as one would like.

What I'd like to see (and would have insisted on as a reviewer) is a table showing the raw numbers of minor and Governor's reports issued on each population over the study period, and at least histograms showing the number of individuals in each populations with N Governor's and M minor reports against them, which would allow one to judge the distribution of incidents in the population.

>It is nearly impossible to be objective about your own brain.

People can't trust their own perceptions? Isn't that what gaslighting is about? Why do we accept eye-witness testimony in court cases if people should not trust their own perceptions?

If a person saw another person strike another person, should we trust their testimony? No! We should have a double-blind placebo controlled experiment where we go back in time and have a large sample size of identical people watching the same person getting struck and not struck in alternate universes and ask them if the person was struck to determine if their perceptions can be trusted.

Eye-witness testimony is mostly bunk and is often not trusted in court. It's been shown over and over that eye-witnesses can be manipulated (even without their knowledge) and are not reliable.

No, you can't trust your own perceptions. You can only really trust that you are having a perception at this moment in time.

At some point I had to take medication where one of the known side effects where higher blood pressure.

I also noticed a significantly increased blood pressure every time I took this medicine.

This continued until one day someone knocked the door just before I took my pills, and I still got the same symptoms while the pills where safely on the kitchen.

I then realised my brain had played games with me and since then the side effects disappeared.

...and I consider myself somewhat rational.