Cognition and Evolution

Consciousness and how it got to be that way

Sunday, December 7, 2014

Neuropsychiatric Diseases Cause Disproportionate Suffering

I've been poring over disability adjusted life-year statistics for the U.S. One of the things that made me choose psychiatry was that there are a lot of diseases that cause horrendous suffering, and one of the horrendous things about it is that this is suffering that can last a lifetime; they're not directly fatal illnesses in the same way that cancer or heart disease are. This highlights the conflict in medicine between decreasing suffering, and decreasing death. It's underappreciated by many people (including, in my experience, physicians) that these are not the same thing; that in fact there are many times when avoiding one can lead to the other, and vice versa. (One way to think of the job of a physician is to protect and extend the possibility of positive future experience.)

Disability-adjusted life years is the sum of years lived with disability (YLWD) and years of life lost (YLL) due to the disease. Granted, living with disease A for 10 years is likely to cause different suffering than disease B over the same time, but this gives us an idea. And the statistics are given in time per person across the population. Consequently if a disease causes lots of disability but is rare, it will have a lower number than another which causes less disability but is very common.

Some points that emerge from inspecting the data:

1) If you look at the ratio of YLWD to YLL, you can see which diseases kill quickly without much suffering (i.e. lots of people die from it but not many years lived with disability). On the other hand, if you want to focus on diseases that cause disproportionate suffering, you look for diseases with a high disability years to life lost ratio. In decreasing order, the diseases out of the top 50 that have the highest disability years:life lost ratio are: major depressive disorder, bipolar disorder, back pain, anxiety disorders, schizophrenia, alcohol use disorder, and drug abuse, COPD. One quirk is that suicide is listed separately and depression, bipolar and a few others have no stats for years lost, and suicide is how people die from depression and bipolar. So, if you make the simplifying assumption that suicide and MDD have a 1:1 correlation, i.e. everyone who dies from depression dies from suicide and everyone who commits suicide does so out of depression, the list doesn't change that much (now, bipolar disorder, back pain, anxiety disorder, schizophrenia, MDD, alcohol, drugs, COPD.)

The trend here toward neuropsychiatric disorders is clear.

2) Comparing the genders, it's unsurprising to see that women fare better than men. What's more, women's outcomes have improved more over the period 1990-2010, in conditions relating to behavioral risk-taking and impulse control - e.g., road injuries and drug use.

3) Embarrassingly, years per population lived with disability for schizophrenia, dysthymia nad bipolar are all essentially flat for this 20 year period. That's bad. That is not the case for most other major diseases.

4) The rise in death and disability over this period from addiction remains staggering. For added irony, a huge proportion (possibly the majority?) of this represents prescription drug abuse. This represents a major, major policy failure on the part of drug enforcement agencies - you know, the ones that have marijuana scheduled as more dangerous than synthetic opioids. The agencys' position must be: hey, people are suffering and dying, but it's a-okay as long as it's not from street drugs!

Wednesday, July 23, 2014

Tramadol: Synthetic Compound is Not Synthetic

Tramadol has been isolated from an African medicinal plant, Nauclea latifolia. Interesting because tramadol was synthesized first, then found to be present in nature (and a known medicinal plant) later.

The rubeaceae family also contains coffee and Psychotria viridis (source of DMT in ayahuasca). Useful-to-humans chemistry seems to concentrate oddly in certain plant families, quite apart from any human eugenics; solaneacea is another good example. (Note that the compounds produced by these families are not chemically similar or necessarily the result of the same pathways - it seems like it's the abstract property of chemical utility to mammals that is shared within these families - which is why this is so unexpected.) Oddly, DMT was also synthesized before it was discovered in nature.

Monday, June 30, 2014

The Endowment Effect as a Rational Strategy

The endowment effect is well-studied: people assign higher worths to their own possessions than to same things owned by someone else. That is to say: you wouldn't pay more than $30 for that couch on Craigslist, but when you list your own - same model, same condition - for some reason, you ask (and somehow, actually expect!) $75.

To many of us there are two central features of cognitives biases that make them so interesting. The first is that they're cognitive biases, not cognitive stupidities. We aren't just all over the map due to limited brainpower, as bounded cognition models would suggest; we consistently make mistakes in the same "direction". This consistency (even if it's consistent incorrectness) leads to the other interesting aspect of cognitive biases, which is the extent to which they might actually be instrumentally rational shortcuts in disguise, either being seen out of context or profitable only over the long run. That is, perhaps when we were hunter-gatherers, they were useful. For example, hyperactive pattern detection (type I error) is a terrible thing in the modern age when we're looking for incoming nuclear warheads, but during the Pleistocene, we were stupid and it couldn't get us into too much trouble. Sure, maybe you might end up thinking the gods struck the mountain with lightning because your children cursed a lot that morning, and a thousand other strange things, but we couldn't really do too much about our strange beliefs anyway - but if that one time you saw a shape in the grass that looked like a hyena, and it really was a hyena - well, you still came out ahead.

There's a lot in behavior and medicine like this that only makes sense in evolutionary context, for instance fever. Fever is not something that pathogens do to us, it's something that our bodies actively choose to do to them. In the modern age it's really hard for us to understand how fever can be beneficial, until we remember that merely two centuries ago when, without medicine, we could (and often did) die of fevers. But this is a kind of base-rate fallacy. Fever is a way our body shakes off pathogens, and before modern medicine, that cut in your foot might have a 70% chance of going septic and killing you. If the fever only has a 65% chance of killing you, you still come out ahead of any competitor who didn't have a fever response.

So how could a completely judgment-clouding bias like endowment effect ever be helpful? Finding a group of people who don't appear to have it might point us in the right direction. And indeed, Apicella et al found that Hadza hunter-gatherers in contact with markets show the endowment effect just like the rest of us, but Hadza way out in the bush away from markets do not.

This is pretty amazing - there's a difference in a known bias, even within the same group of people. So we've already learned one thing: the endowment effect is a learned behavior. So either we post-agricultural types are stupid, or we're getting something out of this bias. What's the benefit? And what exactly is different about the two groups of people that makes one group adopt this strategy?

A simple model of markets assumes information symmetry between participants. But in reality, specialization of labor means that the person approaching you to buy your possessions will almost always have better information than the aproachee who's selling them, because the buyer buys (cars, computers, art, etc.) all the time - and if they're initiating the transaction, they are even MORE likely to have better information. Therefore, the endowment effect may be a learned behavior whereby we value our own possessions more highly than is justified on the open market as a defense against information asymmetry.

Here's a concrete example. Imagine you're selling a car. You seek out an offer, and you find another individual buyer. Are you more comfortable that you're getting a fair deal from them than the car dealer? Of course you are. Now imagine you're approached out of the blue by someone who buys cars for a living. Sure, you'd consider it, but only at a very high price where you're sure you're not getting swindled. (This isn't to suggest that the endowment effect occurs consciously, but you can see how when we calculate consciously, we might behave in exactly the way the endowment effect would influence us.)

Consequently, you can imagine the endowment effect as the cushion you need to come out even, when someone with better information than you buys your possessions, especially one who's initiating the deal. And returning to the Hadza hunter-gatherers, we may have identified the relevant difference. Hunter-gatherers are less specialized. If you're a hunter-gatherer, you know just about everybody you could possibly buy or trade something from, and there's not much special knowledge to allow information asymmetry - i.e., everyone is equally smart about the relative value of gazelles and axe heads - so there's no cause to develop such a bias.

This theory makes several testable claims.

1) The more information asymmetry that exists between possession-owner/seller and the buyer, the more the endowment effect gap should be. You think your car is worth more when the car salesman runs up to you on the street initiating and offer to buy it, than when you're selling to someone online with apparently equal knowledge about cars.

2) The endowment effect gap should be larger in markets where there is poorer information, there is less trust, and for goods that are more difficult to value. Complex goods are more difficult to value.

Not central to the theory, but relevant to the fact that this appears to be a learned behavior: children at some arbitrarily young age should not show the endowment effect, because if this differs between humans, it's learned behavior; kids haven't been swindled out of their possessions enough times. (And what is this arbitrarily young age?) Non-hunter-gatherers who nonetheless live in small groups of people with little interchange with other populations should lack this bias. Hunter-gatherers should develop this bias after they come into contact with markets.

There is also a kind of Coasian consideration separate from the theory. Yes, you might have just gotten a good deal for your used Toyota, but now you have a Nissan and there's a utility cost to you of learning how to operate a new car. If that's ALL the endowment effect is, then each individual's ability to learn new behaviors should completely predict the entire strength of the endowment effect in each individual, at least with complex things like cars.

Thursday, May 29, 2014

Real Trolley Problems Are Here

Cross-posted to Speculative Nonfiction.

Trolley problems are moral exercises (or experiments) where participants are asked to choose between horrible choices, to see how our moral reasoning works. For instance: do you push one person onto the tracks of an out of control trolley to keep five people further away from getting run over? Or do you just not say anything if you see a single careless person wandering into the trolley's path of his own accord, to keep those five people safe? Among other interesting observations in these experiments, we are inconsistent, and people who claim vastly differing moral foundations (religious and atheists, for example) tend to choose the same answer, as long as they're otherwise from the same cultural background (e.g., they're both American). Some enterprises already exist attempting to "solve" morality, that is to be able to program it into a computer, partly motivated by a belief in the impending technological singularity.

Trolley problems are criticized as being able to give us a window into actual moral reasoning for some of the same reasons same reasons as any consequence-less self-report method. But literal trolley problems are now becoming consequential, now that we have driverless cars. Their engineers have to encode how these cars will decide who to hit, if they find themselves in a situation where they have to hit someone. If they have a choie between a helmeted and non-helmeted cyclist, shouldn't they aim for the helmeted cyclist to minimize harm?

If only things were as simple as Asimov's Three Laws of Robotics.

Saturday, April 26, 2014

The Mortality of Aircraft Wheel-Well Stowaways

Cross-posted to my outdoors blog.

The FAA gives a report of 11 known stowaway incidents from 1947-1993.

Of these 11, 6 died. 2 of them had definitely frozen to death. 3 more fell after the plane made it to cruising altitude, and could have frozen to death. Another fell on takeoff. This means that you have a 55% chance of dying if you attempt this, and if you die the chance is 33-87% that you will freeze to death.

Of course it's likely that other fatalities occurred but were not discovered because the plane was over water or the body landed in an unpopulated area; it is also likely that people stowed away and were not discovered, so it's hard to say which way the sample is biased.

The mechanism cited as probable pathway to fatal hypothermia at altitude seems very likely to be the same one that explains the strange behavior of high altitude mountain climbers who succumb to a similar fate, and are found having taken off most or all of their layers. Under conditions of low ambient O2, the hypothalamus becomes hypoxic and can longer thermoregulate. In climbers, their frontal lobes are hypoperfused, and they feel hot and can't reason themselves out of/inhibit themselves from taking their clothes off in the middle of a glaciated mountain. Stowaways are crammed in and can't move anyway.

Management: don't be in a plane at cruising altitude outside a warmed and pressurized cabin.

Sunday, April 20, 2014

Treasures in the Ghettoes of Pubmed

"Werewolves and physicians experienced their closest contact in the context of early modern witch and werewolf trials."

Best opening sentence of a paper ever. From Metzger N. Battling demons with medical authority: werewolves, physicians and rationalization. History of Psychiatry 24(3) 341–355, 2013.

Discovered in the same Pubmed search: Høyersten JG. The berserkers--what was wrong with them?. Tidsskr Nor Laegeforen. 2004 Dec 16;124(24):3247-50. Surprisingly, only in Norwegian.

And a final gem, where I present to you the abstract: Psychopharmacology of lycanthropy (Davis et al 1992) (do note that there is an actual full paper behind this abstract:
OBJECTIVE: To develop pharmacotherapies for the orphan disease lycanthropy through the pursuit of the etiologic hypothesis of a genetically determined hypersecretion of endogenous lycanthropogens. DESIGN: Quadruple-blind, Rubik's Cube matrix analysis. SETTING: Community practice and malpractice. PARTICIPANTS: Subjects selected from inbred Ruficolla populations in Mississippi, Georgia, North Carolina and Minnesota. All who entered the study finished it. INTERVENTIONS: Chemical screening of blood samples over a hypothesized secretory cycle of lycanthropogen peaking on the day of maximum lunar illumination. Administration of synthetic lycanthropogens for behavioural testing. Experimental lycosomatization through the illumination method of Kirschbaum. OUTCOME MEASURES: None were post hoc, but some are still in hock. MAIN RESULTS: Two putative lycanthropogens were isolated from the blood samples. Structural elucidation and synthesis permitted animal and clinical trials; in each of these, behavioural dysfunction was observed. Antilycanthropogen strategies included application of the principle of caged compounds and generation of a therapeutic immunoglobulin. The effects of a newly developed antihirsutic agent seemed promising. An interaction of the lycanthropogen-secretion system and ethanol was noted, which may explain behavioural aspects of alcoholism. CONCLUSIONS: The incidence of lycomania in North America is underestimated. Soon-to-be-available pharmacotherapies should promote its early detection and treatment. Full control may depend upon advances in gene therapy.

Saturday, March 1, 2014

Rounding Up Critiques of Zimbardo's Prison Experiment

Not the first time such critiques have been made, but this post (caveat lector) has some interesting information I didn't know, including the involvement of the Navy and Zimbardo's ongoing association with the DoD.