OK, I’ve got to stop putting off writing this piece about the genetics of procrastination. I’ll just check my mail first. Oh, here’s an update on the genetics of autism. This huge Swedish study, which was just published in the Journal of the American Medical Association (so it must be true), is showing that the heritability of autism is 50 percent.
Now that’s interesting, because the procrastination study that I’m supposed to be writing about, a big twin study from the University of Colorado published in Psychological Science last month, showed that the heritability of procrastination was 46 percent.
And that rings a bell because of something I just read by psychologist Timothy A. Pychyl, of the Procrastination Research Group at Carleton University in Ottawa. Blogging about the procrastination paper at Psychology Today, Pychyl points out that study after study of personality traits show that each of them is . . . about 50 percent heritable.
On heritability
I don’t know that anybody understands why behavioral genetics research consistently shows that wildly disparate aspects of personality so often have a heritability of about 50 percent–although I’ll bet there’s a message there waiting to be figured out.
But I do know that “heritability” doesn’t mean what you might assume it means: that half of autism or procrastination or other personality traits are caused by genes.
Heritability is a technical term, a mathematical formula that does not apply to individuals. It applies only to populations—and only to populations that vary. It’s a measure of how much of the population variance of a trait is genetic.
Hair color is a fine example, frequently cited. In China, hair color varies hardly at all. Thus the heritability of hair color there is low—even though natural hair color in China, as elsewhere, is due entirely to genes. In the U.S., the heritability of hair color is high not because it’s somehow more genetic here, but because there’s an enormous variety of natural hair color in our heterogeneous population—and nearly all of it is genetic. (We’re talking natural hair color here, so I’m saying “nearly all” only to leave room for the lightening effects of the sun. This excludes henna, platinum blondes, toupees, blue streaks, and the many other calculated commercial transmogrifications of hair color.)
The problem with the term “heritability” is that it often leaves people, even some knowledgeable people, with completely wrong impressions. Heritability, remember, has nothing to do with individuals. It does not mean that 46 percent of my procrastination is because of my genes and the rest is a product of environmental factors. Also, to say that a trait is 46 percent heritable (or 5 percent or 95 percent) does not mean that a single gene causes it, or even a small group of genes.
But it’s soooo easy to slide into that sort of misunderstanding. For one thing, journalists like me hardly ever take the trouble to explain that heritability is not about genes in individual people. It’s a difficult concept to get one’s head around and a difficult concept to explain, and we are terrified of boring the audience and driving readers away.
On behavioral genetics
And it’s soooo appealing to believe in genetic causes for behavior, especially bad behavior. It takes us off the hook, relieves us of responsibility for making defective decisions. My genes made me do it.
Some of that is understandable, I guess. Non-genetic influences on behavior are complicated and very, very messy. They potentially include pretty much everything that happens, from the circumstances of your birth to air pollution to the people you went to high school with to what you ate this morning, not to mention what you ate ten years ago or what your grandfather ate at puberty. No hope whatever of sorting that all out and identifying the (ten or a hundred or a thousand) things that make me drag my metaphorical feet when faced with, say, writing an article about procrastination.
If something is partly genetic, that means it is shaped by the presence (or absence) of proteins that are the products of genes. That process is deeply messy too, and the more we learn about it, the messier it gets. But genes and their proteins have the aura of being more manageable. Proteins are tangible physical entities, and in theory they can be prevented from doing something (or encouraged to do something), for example by chemicals produced by the pharmaceutical industry. Someday, perhaps, I will take a pill and be able to get right to work.
Except that for some tasks, getting right to them may be a mistake. If I hadn’t delayed writing to check my mail, I wouldn’t have known about the autism paper. And if I hadn’t read the autism paper, it wouldn’t suddenly have hit me that aspects of personality routinely turn out to be about 50 percent heritable, and to wonder why. A question I hope someone will answer some day.
I’ll have more to say about the virtues of procrastination in a minute, but I’m putting it off for now.
The procrastination paper
I don’t want you to think I’m sneering at the procrastination paper. It has much interesting to say other than providing a heritability estimate that is all-too-typical of behavioral genetics studies—and, therefore, not terribly illuminating.
The procrastination research used classic twin-study methodology, comparing identical with fraternal twins. The theory is based on the idea that identical twins share 100 percent of their genes. (We now know that isn’t quite true, but never mind.) Fraternal twins are genetically no more alike than any other pair of sibs, on average sharing 50 percent of their genes. Thus, if identical twins are more similar to each other than fraternal twins are for a given trait, the trait must have a genetic component. That’s because these twin pairs were raised together, which in theory wipes out environmental differences between them. (We now know that isn’t quite true either, but never mind.) Twin studies have long been a mainstay of genetics research, especially behavioral genetics research. For a critique of the twin-study methodology see this recent post of Greg Laden’s.
Among the paper’s points of interest is that it builds on previous studies linking procrastination—the authors define it as “the voluntary but irrational delay of an intended course of action”— to the well-studied personality trait of impulsivity. There’s a lot of professional disagreement about how exactly to define impulsivity. But for now let’s say impulsivity is acting on whim, the tendency to rash action without forethought. It’s a component of several psychiatric disorders. The Colorado authors put the heritability of impulsivity at 49 percent.
They argue that procrastination is a byproduct of impulsivity. This even though the two may seem contradictory, since procrastination is about delaying action and impulsivity is about plunging heedlessly into action.
But you can see that they are related, too, because I impulsively checked my mail at least partly to postpone writing about procrastination. Discussing this paper at the PBS Newshour, Rebecca Jacobson confessed to having “checked Facebook more than 35 times, watched 10 totally unrelated YouTube clips and browsed BuzzFeed. And I can’t even count the number of times I opened my email.” At least I am innocent of Facebook, YouTube, and BuzzFeed. This time.
The Colorado researchers’ more basic point is to relate these two, procrastination and impulsivity, to our ability to manage goals. They say, “From this goal-management perspective, procrastination is about irrationally delaying actions that help accomplish one’s important goals, whereas impulsivity is about giving in to temptations, often at the expense of making progress on important long-term goals.”
Pychyl thinks they have put their collective finger on the real issue in understanding procrastination and its relation to impulsivity. These two are failures of self-regulation, the inability to manage goals.
This seems like a plausible scenario to me, the idea that what is going on here is, ultimately, allowing distractions to get in the way of getting on with it. On the other hand, it doesn’t allow for the differing reasons for delay, for giving in to impulse. There’s a big difference, for instance, between delay due to sloth and delay born of anxiety.
For example, last night I delayed going to bed in order to watch part of a favorite movie, “Adaptation.” “ Adaptation” is a very funny but very un-Hollywood account of a Hollywood screenwriter’s panicky procrastination when faced with the near-impossible task of (as he puts it) writing a movie about flowers. (Spoiler: He figures it out, and cleverly too.) For a writer–I speak from experience–procrastination can be a tool, a way of giving the brain, its unconscious processes mostly, time and space to work on solutions. I expect that’s true of endeavors other than writing, too.
I’m aware that may sound only like an alibi.
Managing procrastination, impulsivity, and goals
Note that the Colorado researchers’ analysis of what procrastination is about–a failure to manage goals effectively–is stated in psychological terms. In fact, it’s stated not only in psychological terms, but in moral terms. There’s no mention of genes at all.
This is not to argue against genes playing a role in these behaviors. How could they not? But no genes involved in procrastination or impulsivity or goal-managing have been identified. Maybe some will be eventually. But for the moment this is not really a biological analysis. It must be couched in the language of psychology—and the language of virtue.
Note too that 46 percent heritability means that this behavioral genetic study shows that 54 percent of the population variance in procrastination is attributable to non-genetic factors. We don’t know what those are either. But at least it’s clear that “procrastination” is not hard-wired.
Which we know by observation and experience anyway. Some people procrastinate more than others, and a few are dangerously irresponsible and feckless, but nobody procrastinates all the time. Most of us procrastinate some of the time but still are able to restrain the worst of our impulses, meet most of our deadlines, and manage our goals adequately. Nor, as I argue above, need these behaviors always be bad. Sometimes procrastination is a tool for managing goals successfully. Truly.
Also, we can modify a tendency to procrastinate. The self-help literature is stuffed with tricks for doing this. We can remove tempting distractions, keep color-coded calendars and todo lists, check off completed tasks, reward ourselves when we meet a deadline. Etc.
It cannot be said too often: Genes are not destiny.
Tabitha M. Powledge is a long-time science journalist and a contributing columnist for the Genetic Literacy Project. She writes On Science Blogs for the PLOS Blogs Network. New posts on Fridays.
