Monday, August 20, 2012

Normal is not a definition

kw: book reviews, nonfiction, psychology, psychiatry

What is normal? It depends. My Funk and Wagnalls dictionary has several definitions, and even the first, purportedly primary, definition is not definitive: "Conforming to or consisting of a pattern, process or standard regarded as usual or typical; natural." Do you see that last word there, "natural"? It conflicts with the rest of the statement. Properly speaking, the first 15 words define "normative". ("Normative" has its own definition a ways down the page, one which is identical in meaning to those 15 words) "Natural" is a good first definition, particularly when we realize that nature embodies a range of "natural variation".

For about 200 years, psychologists and statisticians have developed an understanding of the "normal distribution", also called the Gaussian distribution. It crops up everywhere because of the way variation is so often dependent on many factors.

For example, the height of uninjured, healthy, adult male Norwegians has a certain range and an average value (about 1.8 m or 71" or 5 ft 11). The height of a particular Norwegian man is derived from many factors. There are many genes that influence how large the body grows; and also the kinds of food he ate growing up, the amount he exercised, and perhaps his favorite sport all contributed to his eventual height. Now suppose an otherwise ordinary Norwegian has a height of 1.5 m (59" or 4 ft 11), and another is 2.1 m (83" or 6 ft 11)? Men with either height are rare. However, among male gymnasts 1.5 m is a bit short but not that unusual, and among basketball players 2.1 m is also not unusual. Are both these men normal? Actually, yes. That doesn't mean they are problem-free.

"Normal" among people who vary in all their characteristics is properly understood as a range of variation. A mathematical concept called the Central Limit Theory shows that the normal distribution has no clear limit in either direction. The formula for the probability distribution has a very small but positive value for a height of zero, and also for a height of 4 m. However, for a homogeneous population such as native Norwegians, the standard deviation is about 7 cm, and the probability for someone to be outside the range of ±3 standard deviations (called "±3 sigma") is about 1 in 750. That means 1 in 1,500 for men shorter than 1.62 m (64") and 1 in 1,500 for men taller than 1.98 m (78"). A man who is 1.5 m tall is at -5 sigma, and the one 2.1 m tall is at +5 sigma. The probability for each is about one in 3 million. There are about 5 million Norwegians, so we might expect to find, on average, one perfectly healthy man who is shorter than about 1.5 m, and one perfectly healthy man who is taller than about 2.1 m, in each generation.

At what point would most people look at a man walking down the street, who is either quite short or quite tall, and say, "That isn't normal"? Now we are talking about what is normative. The fact is, society tends to cater to people who are within ±2 sigma of average, in height, intelligence, and BMI, which are the main three things you can measure. That range, from -2 sigma to +2 sigma, takes in 95% of us. The other 5% are just expected to cope with a world that isn't really made for them; for example in the U.S. doorways are 2 m tall and countertops are about 0.75 m high. Those who have trouble coping often wind up being classified as "handicapped" in some way. They may be "normal", but they are not usual, and that causes problems.

There are other characteristics that are harder to measure: a tendency be trusting or suspicious, one's ease or difficulty of forming loving attachments, the quickness or slowness of "temper", or the tendency to be altruistic or selfish. With several dozen psychological dimensions available, it is distressingly common to fall outside the ±2 sigma range on at least one of them. Some psychologists estimate that about half of us, at some time in our lives, will have a "condition" that can be diagnosed as "abnormal", or at least, treatable. I find that a bit disturbing, and I am not alone.

Professor of Psychiatry Jordan Smoller has written the first book (that I have seen) advocating the study of normal psychology: The Other Side of Normal: How Biology is Providing the Clues to Unlock the Secrets of Normal and Abnormal Behavior. I just checked; there are more than 4,000 books with "Abnormal Psychology" in the title, and 47 published in the past 90 days. There are only 35 titles containing "Normal Psychology", but most of these are editions of Mental Pathology in its Relation to Normal Psychology by Störring and Loveday. It is pretty safe to say that Dr. Smoller currently has the field of normal psychology to himself.

The thesis of his book is quite simple. William James a century ago wrote that "the best way to understand the normal is to study the abnormal." The result has been a steady process of studying various pathological conditions and staking out a supposed range of behavior (a syndrome) to define it. There is no doubt that the Diagnostic and Statistical Manual of Mental Disorders (DSM), now in version IV, has helped standardize communication among mental health professionals. However, the "edges" of the diagnoses are necessarily hard to specify, leading to continuing encroachment on "normal" territory. Only about half the people are still "normal", and that doesn't include me, because of my diagnosis as Bipolar II.

Is someone with a diagnosable condition, who can cope well with it, sick? Like many writers who are bipolar, I've learned the rubric, "When you are up, write, and when you are down, edit." For people in creative professions, a certain level of bipolarity is a benefit. It opens up a wider range of creativity, and also allows one those periods of narrowed focus necessary to prune the extra wildness off and complete work that might otherwise need the services of an expensive editor (painters and sculptors can't use editors, but writers and composers and lyricists can; and dancers' and actors' "editors" are called choreographers and directors).

I have two friends who are schizophrenic. One knows it and the other doesn't. The one who knows it used Thorazine for a time, but learned to cope with his inner demons so he could get off Thorazine, which has devastating side effects. He makes his living by tutoring in electronics and computer programming. The other fellow is institutionalized because it would take extreme force to put a pill down his throat. If left to his own devices, he hitchhikes around the country, which isn't bad in itself, but he can't earn money so he becomes a danger to himself. I guess I can't really call him a "friend" any more, since he can't reciprocate my friendly feelings. He is a likeable guy most of the time. I guess these men represent two ends (or near-endpoints) of a schizophrenia spectrum.

In seven chapters of the book, the author considers the intricate dance of genetics and environment (including family upbringing, if there was one) that influence a person's mental makeup—the genetics of behavior may take up 10% or more of our genome, so no one gene is the "gene for" any characteristic—; various ways researchers have used to tease out environmental influences; the surprising role of epigenetics, which is actually a non-Mendelian means of heritability; and the ways we can choose to change our behaviors (it ain't easy but it is possible!). He ends with a plea in favor of studying the normal ranges of behaviors, intending to turn William James's dictum on its head. It now seems better to study the normal so as to better understand abnormality.

In height, being tall is an advantage for getting a job and a mate, but being super-tall is not super-good. Men taller than about 2 m have paradoxically few jobs open to them. They duck through doorways; people stare at them (or try very hard not to stare). If they have exceptional athletic coordination, they might become professional basketball players, but for the rest, being unusually tall brings with it trust issues. It is also paradoxically difficult for those with extreme IQ's to get work. There are two issues here. Firstly, someone with an IQ greater than 160 probably grew up lonely. At +4 sigma, he or she was one in 32,000 and probably had no acquaintances of similar brilliance. This leads to significant social ineptness. Secondly, people with extreme IQ's have different interests, or you could say, they are seldom interested in things that interest those in the ±2 sigma range. This makes it harder to communicate with a boss or a customer. That is why Mensa was started.

In other areas, being "super" may not be possible. In the chapter on "Baby Einsteins", Dr. Smoller points out that an overloaded "learning" environment is probably akin to a hyper-oxygenated atmosphere. The body can only use so much oxygen. When we need extra, we breathe deeper, but going to the "oxygen bars" that cropped up some years ago didn't do the patrons any good, though it fattened the wallets of the proprietors. Alert: SCUBA divers know that pure oxygen at twice atmospheric pressure is toxic. If you fill your tanks with pure oxygen and dive deeper than 30-35 feet, you'll die; if you use regular air, you can dive to 150-170 feet, and then you'll die of oxygen poisoning. To go deeper you need special oxygen-poor gas mixtures. Fortunately, making your baby listen to Mozart music won't poison the little tyke, but it will not raise IQ.

So why is the "Mozart effect" popular? The studies upon which the craze is based are flawed. They didn't take into account the fact that parents who might play Mozart for their infants are also more likely to read to them, play with them, and take them places. That is what helps the kids' minds develop. Parents who plop a a little one in front of an "educational video" for a few hours a day will probably find the child is more passive in school and could have trouble learning.

So far, I have neglected the "biology" portion of the thesis. Our brain is biological. Most of modern pharmacology of behavior is based on a number of accidental discoveries that are some forty years old. Much more recent work with chemicals such as oxytocin is just beginning to hint that better chemical interventions are possible. Here is where Dr. Smoller's caution is advisable: we really, really need to know what is normal before we do any more manipulation of people's minds. Otherwise, how do you know when they are "better"?

How do you define success? This lack of a defined target leads to people who spend years and years in psychoanalysis, with little change. Aimless maundering to a clueless therapist is like circling under a lamppost, just because that is where the light is. A proper study of normality, and of the amazing adaptability of all of us, can shine more lights where today most are groping in darkness.

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