The positive psychology movement, which studies happiness, is not really all that old, but it’s old enough for some of its findings to have become so widely accepted that you run into them everywhere. One of these is the set point, a level of happiness that varies from person to person (perhaps due to genetic causes) and tends to persist throughout a person’s lifetime. The idea is that life events may nudge you away from your set point in one direction or the other, but sooner or later you’ll adapt to even major changes in your circumstances. This press release from EurekAlert describes some recent work that found that it’s not that clearcut. A review of the data from two large studies showed that some events are more easily adjusted to than others, and there’s also a good deal of individual variation. We do still adapt, but the phenomenon is more nuanced than a simple individual set point that people invariably return to.
Modeling the evolution of communication
This press release from EurekAlert describes some research into how communication strategies evolve among social creatures. This is a difficult area to study by observing the creatures themselves, but a group of researchers looked at the behavior of virtual robots with virtual genomes that evolved over time due to recombination and mutation. They ran multiple generations of these robots under different conditions in an environment that included food sources and poison sources and was set up to more or less realistically present the same evolutionary pressures—costs and benefits for signalling the location of food, for example—as the real world does for real live social organisms. The conditions that the researchers varied included whether selection was stronger at the group or the individual level, and whether the colonies of robots were genetically similar or not. After running the simulations, they used the genomes from the simulations in real robots, and the real ones behaved as the virtual ones had.
The press release noted that the circumstances that favored rapid evolution of communication are those in which group-level selection was stronger and those in which the robots in a group were genetically similar. Another finding that really struck me is that once a communication strategy was in place, it tended to limit any possibilities for enhancing communication; the cost of disrupting signalling to change things, even for the better, was steep enough that even a sub-optimal system was fairly stable. To quote from the full paper in Current Biology (by Dario Floreano, Sara Mitri, Stéphane Magnenat, and Laurent Keller):
“Importantly, our results show that once a given system of communication has evolved, it may constrain the evolution of more efficient communication systems because it would require going through a stage where communication between signalers and receivers is perturbed. This finding supports the idea of the possible arbitrariness and imperfection of communication systems, which can be maintained despite their suboptimal nature. Similar observations have been made about evolved biological systems, which are formed by the randomness of the evolutionary selection process, leading, for example, to different dialects in the language of the honey-bee dance.”
Contingency and imperfection…the stuff of life.
Religion and aggression
This news story is related to some comments in response to the review of the Richard Dawkins book that I posted the other day. The comments have turned to the question of the relationship between religion and aggression, and this press release describes some recent research into that very thing. A psychologist at the University of Michigan led a group that looked at students at Brigham Young University and at Vrije Universiteit in Amsterdam; a much higher percentage of the BYU students reported a belief in God and in the Bible, as you would expect. The students read a story from the King James Bible describing a nasty incident involving torture, murder, and revenge; some of them were told it came from the Bible but others were told that it came from a scroll found at an archaeological site. For some participants in each of those two groups (the Bible group and the scroll group), the story was augmented with an additional verse about God instructing Israel to chasten its brothers before the Lord. After reading the story, the students paired up for an interactive test that measured aggression (the winner of a competition got to assault the eardrums of the loser with a loud noise, at a volume the winner chose, up to about the volume of a fire alarm).
The results are very interesting. The BYU students displayed more aggression if they thought the story came from the Bible than if they thought it came from some random scroll, and also if they got the extra verse about chastening their brethren. The students from Amsterdam also were more aggressive if they got that extra verse, although they weren’t as strongly influenced as the BYU students by what they thought the source of the story was. (It’s especially interesting that even the non-believers were apparently influenced by that verse about God urging Israel to fight its brothers.) The closing paragraph of the press release discusses what the results of the study might have to do with the roots of religious terrorism.
Of course many people who read the Bible ignore the more violent verses, but there’s a surprising amount of strong language about what God will do to unbelievers even in the supposedly kinder, gentler New Testament. The Skeptic’s Annotated Bible lists relevant passages (there’s also an annotated Quran and an annotated Book of Mormom).
Book review: The God Delusion
A number of books on the theme of faith and reason have been published lately. I just finished one of them, The God Delusion, by Richard Dawkins. This book gives a broad view of a number of questions in the faith-and-reason debate, all written with Dawkins’s characteristic style and wit. I enjoyed reading it, and although much of the material was familiar to me, I still feel like I learned a few things.
Dawkins starts out by laying out exactly what sort of God he believes is a delusion–i.e., a supernatural being. Actually, he starts out by describing what he means by “Einsteinian religion”, the use by scientists of religious terminology in a metaphorical or pantheistic sense, because that is not the kind of God he means. He has some good quotes, like this from Einstein, which he used to sum up Einsteinian religion:
“To sense that behind anything that can be experienced there is a something that our mind cannot grasp and whose beauty and sublimity reaches us only indirectly and as a feeble reflection, this is religiousness. In this sense I am religious.”
Or this from Carl Sagan, which explains very nicely the pitfalls of using “religion” or “God” in the sense that Einstein did:
“…if by “God” one means the set of physical laws that govern the universe, then clearly there is such a God. This God is emotionally unsatisfying … it does not make much sense to pray to the law of gravity.”
Dawkins sums up his own views by saying:
“…I wish that physicists would refrain from using the word God in their special metaphorical sense. The metaphorical or pantheistic God of the physicists is light years away from the interventionist, miracle-wreaking, thought-reading, sin-punishing, prayer-answering God of the Bible, of priests, mullahs and rabbis, and of ordinary language. Deliberately to confuse the two is, in my opinion, an act of intellectual high treason.”
I agree with what Einstein said and I like the way he said it, but, while I wouldn’t word it as strongly as Dawkins does, I can see the value of the point he’s making and I have to reluctantly admit he might be right. I broached this topic with a couple of people who like to think about things like this and it generated some excellent discussion; I’d be interested in hearing other opinions too.
Dawkins describes the God hypothesis—the variety of beliefs that people hold about God, and how (or whether) they try to accommodate these to facts about the world we live in—and gives a brisk run-through of arguments for God’s existence (that’s “run-through” as in “run through wih a sword”, as he gives brief but compelling reviews of the difficulties with each one). There was nothing particularly new and exciting here but I think he did a good job of covering his turf very readably and wittily. He follows this up with an explanation of why there almost certainly is no God.
He devotes a couple of chapters to how we came to be religious animals and to where our sense of right and wrong comes from, discussing human psychology, the possible adaptive value of religion, and memes. (Daniel Dennett covers the origins of religion more thoroughly in his recent book Breaking the Spell: Religion as a Natural Phenomenon, by the way.)
The chapter on what our moral sense tells us was particularly interesting. His main point was that whatever people may say about getting their ideas of right and wrong from the Bible, that’s not really the case. The Old Testament is notoriously blood-soaked and violent, and the God depicted there is often morally unsavory to a high degree. (I have long found the story of Abraham preparing to sacrifice Isaac particularly repugnant, but there are plenty of other stories to make a decent person cringe.) Christians who don’t take the advice of the Old Testament literally are using some other moral yardstick by which to measure what they find in the Bible, rejecting the bad and keeping the good, meaning that scripture is not truly the basis for their moral code.
There’s a fair amount of consensus about that moral yardstick that defines good and bad behavior for us, although over time the consensus changes; Dawkins describes each age as having its own “moral Zeitgeist”. He reported on a study done about 40 years ago by Israeli psychologist George Tamarin that looked at how Israeli children reacted to a passage from the Bible about Joshua and the battle of Jericho, something we might today describe as a massacre. When over a thousand Israeli schoolchildren were asked whether they totally approved, partially approved, or totally disapproved of what Joshua and the Israelites had done in taking over the city of Jericho and slaughtering its inhabitants, 66% totally approved and 26% totally disapproved. When asked to explain their thinking, they gave religious justifications, including statements about the danger of learning bad ways from others of a different religion. (And some of those who disapproved did so on the grounds that property was lost as well as lives, and that property could have been put to good use by the Israelites.) When a smaller control group was given the same story, but with the names and places changed so that it was about a fictitious general who lived in China 3,000 years ago, only 7% totally approved and 75% disapproved. This was a striking and discouraging instance of the influence of religious prejudice on the moral sense of children.
Dawkins spends a chapter on the dangers of religious fundamentalism (and even moderate religion, he says, provides the climate in which fundamentalism can grow). There is plenty of material available to prove his point; this is ground that Sam Harris covered more thoroughly in The End of Faith.
The final chapter is a summary of how life can be full of beauty, meaning, and inspiration despite, or perhaps even because of, an absence of the supernatural. This is also well-trodden ground, but I always relish seeing someone expressing these ideas, especially as beautifully as Richard Dawkins can do it, because in my opinion they cannot be disseminated too widely. He mentions a number of books that you can go to for more in this vein.
Overall I’d say this book is valuable as an overview and a pointer to other resources. I’ve heard people say that The God Delusion is preaching to the choir, and while it may be well presented and engagingly written, it’s not likely to reach the people who really need to read it. But I wonder if it might be a very useful thing for young people who have had a religious upbringing and are in the process of leaving the religion in which they were raised. I wish this book had been around 24 years ago when I was going through my own struggles with leaving the Catholic church. Maybe there were other books that would have helped and I just didn’t find them, but Dawkins’s excellently and compassionately written summary of the key issues might have eased the transition considerably for me. I hope the book finds its way to other people who might find it similarly useful.
Evidence of adult neurogenesis
It’s been a long week and right now I feel like large portions of my brain have shorted out or maybe simply evaporated. It seems like what I heard while I was growing up was that you had a fixed amount of brain cells and while you might inadvertently kill some of them off, you never got any new ones. I don’t really think I destroyed an inordinate number of neurons this week, of course, but still it’s encouraging to see more evidence for neurogenesis, the growth of new brain cells, in adult humans. This article from New Scientist describes the discovery, in adult human brains, of newly created brain cells in a part of the brain that processes smells. Researchers also found a cache of brain stem cells (basically proto-neurons) deep in the brain and a pair of tiny tubes that act as a highway from that stem cell reservoir to the olfactory bulb where the new brain cells were found.
Possible evolutionary roots of depression
The Los Angeles Times recently ran a story about evolutionary psychology as it relates to depression. (Thanks to Cashew for pointing this out!) The article discusses the evolutionary approach that some researchers are taking not only to understanding depression but also to treating it. It’s still early times for this kind of work, so this is an engaging introduction to an obviously dynamic field with more questions than answers at this point.
I read somewhere once that depression might have originated as an adaptive urge to strategic withdrawal to conserve energy and regroup after a setback of some kind, but that’s only one theory. There are several possible types of evolutionary explanations for mental illness in general: that it might have been adaptive because the behaviors it causes evoke care and attention from others when we need it; conversely, that it is a measure of how badly our current lifestyles fit us due to the fact that we evolved for a different sort of physical and social environment than the one we live in today; or perhaps that it is a result of a slow accumulation of mutations.
The explanation about a mismatch between how we live now and how we used to live is familiar because something similar has been used to explain some of our current health problems—e.g., that we evolved in an environment in which fats and sugars were much rarer and signaled a rich energy source, so we developed a strong response to them that works against us now that we are surrounded by easily available sweet fatty foods. And there’s a therapeutic approach to depression in which patients are encouraged “to live more like their Paleolithic ancestors” (e.g., more aerobic exercise, more sleep, more positive social interaction). Personally I’ve found that regular exercise is one of the best ways to keep the blues at bay; in fact I’ve wondered if having fewer exercise opportunities during the winter might not contribute a bit to seasonal affective disorder (SAD) for some people. (Which reminds me that awhile back I wrote this essay, which mentions a possible evolutionary explanation for SAD.)
On the other hand, I’ve always been drawn to the idea that sometimes depression is analogous to physical pain that can alert you to something wrong that needs to be fixed, or simply to a situation where the best course of action is to withdraw. However, depression (and physical pain for that matter) is often complicated, and it’s hard to tell when the pain is something to accept and live through and learn from, and when you need some kind of intervention (behavioral, pharmaceutical, or otherwise) to set things right.
Some of the therapies described sound to me like they’re only somewhat loosely connected with evolutionary psychology. For years therapists have been guiding their clients through imaginary conversations with parents, siblings, ex-lovers, etc., to finish off or rework old emotional business, for example, and I’m not sure I see how that relates to evolutionary psychology. Robert Neimeyer of the University of Memphis was quoted in the article as saying that maybe evolutionary explanations work better at explaining average human behavior than individual problems, which makes a lot of sense to me, so I wonder how useful an evolutionary approach is going to be in the long run in developing therapies.
But treating depression or other emotional disorders is still more of an art than a science, and I’m glad to see that people are working on a better understanding. I’m guessing that any new therapies that come out of it probably will help at least some of the people some of the time. And with any luck we’ll learn something about how we got to be the way we are.
Childhood attachment and adult relationships
In honor of Valentine’s Day, here’s one more article about love, specifically about the psychology of romantic relationships. For 25 years, a group of researchers has been observing 78 people and evaluating the way they experience and express emotions in the context of important relationships. They’ve found links between the subjects’ earliest experiences of attachment and their feelings in later relationships.
The study began when the subjects were babies and has run for 25 years so far; the subjects have been observed at four points in their lives (as babies, in early childhood, in adolescence, and in early adulthood). The researchers have been testing the predictions of John Bowlby’s model of attachment, which describes people’s attachment styles as being secure or insecure (anxious, avoidant, or ambivalent were the “insecure” categories, I believe). Bowlby proposed that our attachment style is partly a product of our interactions with our earliest caretakers, and that it influences subsequent relationships throughout our lives.
The longitudinal study did indeed find correlations between a person’s experience and expression of emotions across the lifespan that’s been studied so far (although the researchers make the point that the attachment style you learn in childhood is only one factor in a complicated situation, so it’s not like it defines your destiny). See this press release from the APA for more information.
Yes, but did they have a wiki?
Well, the header is a little frivolous, but it has been a long hard slog on the day job today, and I have been beset with domestic ills (e.g., the mice that came in from the cold), so I am only now (11:30pm) sitting down with a glass of wine and some chocolate. The winter storm has arrived and the precipitation, whatever it is (sleet? ice pellets?) sometimes clicks against the windows as it falls, making an indistinct rustling sound unhappily reminiscent of mice cavorting in the cupboards, so I am cranking the music up. OK, now I’m ready to blog.
A Canadian archaeologist has discovered some 4,300-year-old chimpanzee tools in the Ivory Coast in Africa. The stone hammers were used to crack open nuts, and evidently required some sophistication to operate correctly. It’s not clear whether humans first began using stone tools like this and chimps imitated them (for these particular tools, there were no farmers at that place and time so it’s unlikely the chimps could have borrowed the technology), or whether both got the behavior from a common ancestor (or both developed it separately). Frankly I hadn’t even known there was such a thing as chimp archaeology, so I thought this was nifty stuff. You can read all about it in this press release from EurekAlert.
Brain activity used to predict mental action
Sometimes I think even I don’t know what I’m planning to do next. But a team of researchers has figured out a way to look at brain activity and predict a person’s future actions. Specifically, they were looking at whether a subject planned to add or subtract a pair of numbers. The technique uses brain scanning and some sophisticated pattern analysis. The eight subjects were asked to decide whether they were going to add or subtract a pair of numbers, and a few second later the numbers were presented. The pattern analysis software examined the brain activity for each volunteer and was trained to recognize the brain patterns associated with deciding on each activity, adding and subtracting (analogous to the way you need to train voice recognition software).
The software was correct in its predictions 70% of the time (this was after 40 minutes of training with a particular subject). There’s some potential for developing this into a tool for paralyzed people to compose text in their heads and have a computer recognize what letters or words they’re thinking of. As with any technology like this, ethical questions could arise in the future. I wonder how similar the patterns for the eight subjects were, and how much it might be possible to generalize in predicting the behavior of subjects for which the software has not been trained. I suppose if you want to keep your thoughts private, you can just stay out of the scanner (for now, anyway).
Here’s the press release from the Max Planck Institute for Human Cognitive and Brain Sciences, and here’s an article from New Scientist.
The insula and addiction
There was a news story recently about smokers who suffered damage to a part of the brain called the insula; some of them totally lost their craving for cigarettes. I hadn’t heard much about the insula before that, but here’s a good article from The New York Times about it (free registration required). The insula is small and is buried deep within the brain, but it’s crucial for interpreting physiological data about states such as hunger, heat, cold, and aching muscles and turning this input into a wide range of social emotions. The insula appears to be involved in an astonishingly wide range of experiences, including addiction, anticipation of the future, and emotional appreciation of music. I like the closing line of the article, which refers to the insula as “a crossroads of time and desire”.
All mammals have insulas, but in humans and to some degree in other great apes, the insula is a much more powerful organ that may turn out to play a major role in what it feels like to be human. Part of the difference in humans has to do with the neural pathways that feed information to the insula. Von Economo neurons (VENS, also called spindle neurons) also play a role. VENs are found only in humans, other great apes, whales (you may remember hearing about the discovery last year that whales have them), and maybe elephants; they occur only in the insula and the anterior cingulate cortex, but it’s not clear what exactly they do in the insula.
Shortly after the smoking story came out, my son Greg sent me a link to a story on CNN about how maybe transcranial magnetic stimulation (TMS) could be used on the insula to quell the urge to smoke in smokers with an intact insula, but I wonder what else they might lose in the process.
The NYT article mentions that people who are better at reading the sensations mediated by the insula score higher on tests of empathy, and I found that interesting. Being somewhat emotionally sensitive myself, I’ve wondered about the neurological correlates of that trait. Maybe the insula holds part of the answer.