More on gay and straight brains.

A recent study notes that in several measures of brain symmetry, straight men and gay women were similar, and gay men and straight women were similar. MindHacks points out a further interesting feature: that amygdala reactivity to simply breathing unscented air (thus having nothing obvious to do with sexual preference or activity per se) is different in gay and straight men and women. This is yet more evidence that sexual preference is not determined solely by individual developmental experience. Here is the complete abstract of the Savic and Per Lindström article, followed by the PET scan amygdala data, which speaks for itself, and finally a clip from the discussion. PDF of article here.

Cerebral responses to putative pheromones and objects of sexual attraction were recently found to differ between homo- and heterosexual subjects. Although this observation may merely mirror perceptional differences, it raises the intriguingquestion as to whether certain sexually dimorphic features in the brain may differ between individuals of the same sex but different sexual orientation. We addressed this issue by studying hemispheric asymmetry and functional connectivity, two parameters that in previous publications have shown specific sex differences. Ninety subjects [25 heterosexual men (HeM) and women (HeW), and 20 homosexual men (HoM) and women (HoW)] were investigated with magnetic resonance volumetry of cerebral and cerebellar hemispheres. Fifty of them also participated in PET measurements of cerebral blood flow, used for analyses of functional connections from the right and left amygdalae. HeM and HoW showed a rightward cerebral asymmetry, whereas volumes of the cerebral hemispheres were symmetrical in HoM and HeW. No cerebellar asymmetries were found. Homosexual subjects also showed sex-atypical amygdala connections. In HoM, as in HeW, the connections were more widespread from the left amygdala; in HoW and HeM, on the other hand, from the right amygdala. Furthermore, in HoM and HeW the connections were primarily displayed with the contralateral amygdala and the anterior cingulate, in HeM and HoW with the caudate, putamen, and the prefrontal cortex. The present study shows sex-atypical cerebral asymmetry and functional connections in homosexual subjects. The results cannot be primarily ascribed to learned effects, and they suggest a linkage to neurobiological entities.

From the discussion:

HeW and HoM displayed more pronounced between-amygdala connections and greater connections with the anterior cingulate, the subcallosum, and the hypothalamus. This connectivity pattern provides a strong substrate for processing of external stimuli that are relayed by the two amygdalae and represents a possible pathway for their functional interconnection in HeW and HoM. The remarkable similarity between HeW and HoM in the connectivity pattern deserves special attention. The amygdala has a key role in emotional reactions to external stimuli, including stress; the subcallosum and the anterior cingulate, on the other hand, are highly involved in mediation of mood and anxiety-related processes. Affective disorders are 2–3 times more common in women than men, and the tight functional connections between the amygdala and cingulate in women is currently discussed as a possible neurobiological substrate for their higher vulnerability, in addition to the effects of estrogen and testosterone. Interestingly, the incidence of depression and suicide attempts is elevated in homosexual subjects, and HoM in particular. Although the underlying mechanisms are likely to be multifactorial and include social pressure, the presently observed similarity with HeW vis-a`-vis the amygdala connectivity motivates further evaluations.

A new mind blog...

At the risk of promoting further blog overload, I've added the Psychology Today blog to the 'other mind blogs' list just under 'Archives' in the right column. It has some good stuff.

Increasing complexity of nerve synapses during evolution

Nicholas Wade points to the work of Grant and colleagues on how the complexity of nerve interconnections (synapses) has increased during evolution as the variety of their protein components has increased from a few to several hundred. Vertebrate synapses have about 1,000 different proteins, assembled into 13 molecular machines, one of which is built from 183 different proteins. The human brain has about 100 billion neurons, interconnected at 100 trillion synapses. Grant provides an analogy:

If the synapses are thought of as the chips in a computer, then brainpower is shaped by the sophistication of each chip, as well as by their numbers...From the evolutionary perspective, the big brains of vertebrates not only have more synapses and neurons, but each of these synapses is more powerful — vertebrates have big Internets with big computers and invertebrates have small Internets with small computers.

The top part of the figure (click to enlarge) shows the phylogenetic relationships of the species studied. The number of varieties of two signaling complexes, NMDA receptor (NRC or MASC) / postsynaptic density (PSD) are in parentheses. The lower half shows the occurrences of PSD and MASC homologs found in each of the 19 species as a percentage of those found in human.

Evolutionary Psychology as Maladapted Psychology

Bolhuis reviews a book with the title of this post by philosopher Robert Richardson. (I have read a longer excellent book, "Adapting Minds", by philosopher David Buller. Here are some clips from the review:

Evolutionary psychology aims to apply evolutionary theory to the human mind. Specifically, it proposes that the mind consists of cognitive modules that evolved in response to selection pressures faced by our Stone Age ancestors. The approach has a wide popular appeal, perhaps because it often addresses such exciting topics as human desire, sex, and passion....Richardson readily acknowledges that our psychological capacities are evolved traits subject to natural selection. But at the same time, he maintains that there is very little we can find out about the evolution of the mind and that the evolutionary psychology interpretation is wrong from the perspective of evolutionary biology...he criticizes mainly the methods used by evolutionary psychologists, weighing the approach's theoretical framework using criteria from evolutionary biology...The main problem with evolutionary psychology is that it usually does not consider alternative explanations but takes the assumption of adaptation through natural selection as given.

Richardson rightly suggests that paleontologists are unlikely to unearth the evidence that can inform us about the social structure of our ancestral communities. I think one can go a step further. Even if we would be able to muster the evidence needed for an evolutionary psychological analysis of human cognition, it would not tell us anything about our cognitive mechanisms. The study of evolution is concerned with a historical reconstruction of traits. It does not, and cannot, address the mechanisms that are involved in the human brain. Those fall within the domains of neuroscience and cognitive psychology. In that sense, evolutionary psychology will never succeed, because it attempts to explain mechanisms by appealing to the history of these mechanisms. To use the author's words, "We might as well explain the structure of orchids in terms of their beauty." In this excellent book, Richardson shows very clearly that attempts at reconstruction of our cognitive history amount to little more than "speculation disguised as results." The book's title implies that the field is itself subject to selection pressure. Richardson is certainly piling it on.

Anticipating the Future to ‘See’ the Present

The title of this post is also the title of an article by Benedict Carey that describes works supporting the idea that the brain uses a bag of ad hoc tricks to build a streaming model of the world. Because it takes the brain at least a tenth of a second to model visual information, it is always working with old information. The argument is that the brain has evolved to meet this problem by projecting or guessing a split second into the future when it perceives motion. By modeling the future during movement, it is “seeing” the present. These two illusions illustrate the process:

Leaning toward the image makes it appear as if it is bulging.

The radiating lines trick the brain into perceiving motion forward, so the center appears to bulge.

Evaluating mental exercises

This article on pumping up your little grey cells in the Times of London is worth reading, also this New Scientist article.

Schizophrenia and the Brain

Here is a very nice instructional video from Thompson at UCLA, whose images I have shown in previous posts, showing brain developmental differences in normal and schizophrenic children between the ages of 4 and 21. It also shows how recently developed drugs inhibit the degenerative changes.

Social cognition in plants?

I suppose it is a bit of a stretch to call it social cognition, but it is recognition of kin and non-kin species, now discovered in plants. This is a bit of a shock, in part because most animals have not even been shown to have the ability to recognize relatives, despite the huge advantages in doing so. Some plants not only avoid competing with kin by not sending roots towards them, but also sniff out their victims. We're talking about careful experiments here, not New Age fantasies about plant feelings and sentience. Check out the account by Yoon. This excerpt is from its ending:

Recent debates have revolved around a longstanding question: which of the abilities and attributes that scientists have long considered the realm of just animals, like sensing, learning and memory, can sensibly be transferred to plants?...At the extreme of the equality movement, but still within mainstream science, are the members of the Society of Plant Neurobiology, a new group whose Web site describes it as broadly concerned with plant sensing....The very name of the society is enough to upset many biologists. Neurobiology is the study of nervous systems — nerves, synapses and brains — that are known just in animals. That fact, for most scientists, makes the notion of plant neurobiology a combination of impossible, misleading and infuriating....Thirty-six authors from universities that included Yale and Oxford were exasperated enough to publish an article last year, “Plant Neurobiology: No Brain, No Gain?” in the journal Trends in Plant Science. The scientists chide the new society for discussing possibilities like plant neurons and synapses, urging that the researchers abandon such “superficial analogies and questionable extrapolations.”

Defenders point out that 100 years ago, some scientists were equally adamant that plant physiology did not exist. Today, that idea is so obviously antiquated that it could elicit a good chuckle from the many scientists in that field...As for the “superficial analogies,” the new wave botanists are well aware that plants do not have exact copies of animal nervous systems...“No one proposes that we literally look for a walnut-shaped little brain in the root or shoot tip,” five authors wrote in defense of the new group. Instead, the researchers say, they are asking that scientists be open to the possibility that plants may have their own system, perhaps analogous to an animal’s nervous system, to transfer information around the body....“Plants do send electrical signals from one part of the plant to another,” said Dr. Eric D. Brenner, a botanist at the New York Botanical Garden and a member of the Society of Plant Neurobiology...Although those signals have been known for 100 years, scientists have no idea what plants do with them...“No one’s asked how all that information is integrated in a plant, partly because we’ve convinced ourselves that it isn’t,” Dr. Brenner said. “People have been intimidated from asking that question.”

A great curmudgeon of our times...

This Deborah Solomon interview with Gore Vidal cracked me up so much I wanted to pass it on:

Q: At the age of 82, you will be publishing your new collection of essays this week, which seems likely to confirm your reputation as one of America’s last public intellectuals. Why do you think that critics have traditionally praised your essays more than your fiction, which includes “Burr,” “Myra Breckinridge” and 20 other novels? That’s because they don’t know how to read. I can’t name three first-rate literary critics in the United States . I’m told there are a few hidden away at universities, but they don’t print them in The New York Times .
Are you saying your novels have been critically neglected? I don’t even read most reviews, unless there is a potential lawsuit on view. I’ve never had much attention paid by critics — nor has anybody else in the United States of America, as Mr. Obama likes to call it.
And what about Mr. McCain? Disaster. Who started this rumor that he was a war hero? Where does that come from, aside from himself? About his suffering in the prison war camp?
Everyone knows he was a prisoner of war in North Vietnam. That’s what he tells us.
Why would you doubt him? He’s a graduate of Annapolis. I know a lot of the Annapolis breed. Remember, I’m West Point, where I was born. My father went there.
So what does that have to do with the U.S. Naval Academy down in Annapolis? The service universities keep track of each other, that’s all. They have views about each other. And they are very aware of social class and eventually money, since they usually marry it.
How, exactly, is your cousin Al Gore related to you? They keep explaining it to me, and I keep forgetting.
What about your grandfather, Thomas Gore of Oklahoma ? He invented the whole state. It was Indian territory. There was no state until Senator Gore.
In 1968, during the Nixon-Humphrey race, you became the voice of liberalism in a series of televised debates with William Buckley. Any plans to be a pundit at the coming presidential conventions? No.
How did you feel when you heard that Buckley died this year? I thought hell is bound to be a livelier place, as he joins forever those whom he served in life, applauding their prejudices and fanning their hatred.
You live in California , where last month the State Supreme Court overturned the ban on same-sex marriage . As someone who lived with a male companion for 50-plus years, do you see this as a victory for equality? People would ask, How could you live with someone for so long without any problems of any kind? I said, There was no sex.
Were you chaste during those years? Chased by whom?
Are you a supporter of gay marriage? I know nothing about it. I don’t follow that.
Why doesn’t it interest you? The same reason heterosexual marriage doesn’t seem to interest me.
If we look at the situation apart from you — It’s my interview, so we’ve got to stay with me.
Have you ever considered leaving the United States permanently? No, it’s my subject.
Do you read a lot of contemporary fiction these days? Like everyone else, no, I don’t.
Anyone in the 20th century you might have a kind word about? Yes, I liked Italo Calvino, and I thought he was the greatest writer of my time.
Your new collection includes an essay in which you note, “Calvino does what very few writers can do: he describes imaginary worlds with the most extraordinary precision and beauty.” What about American novelists? Can’t think of one.
Norman Mailer? Oh, dear, we’re not going to go into pluses and minuses now.
Philip Roth? Ditto.
I admire Roth. He never became complacent. He had no reason to. He’s a good comic writer.
What do you think is your own best novel? I don’t answer questions like that. Ever. And you ought not to ask them.
Well, it was a great pleasure talking to you. I doubt that.

Incense is psychoactive.

Mechoulam and colleagues find that incensole acetate (IA), an ingredient of Boswellia resin (frankincense), stimulates a little understood brain ion channel (TRPV3) to cause anti-anxiety and antidepressive behaviors in mice. This suggest that TRPV3 channels in the brain may play a role in emotional regulation. IA has no effect on 27 other receptors, ion channels, and transport proteins in the brain. The suggests the potential for an entirely new class of depression and anxiety drugs.

Obama and Neuroeconomics

In the New York Review of Books John Cassidy offers an interesting review of Nudge: Improving Decisions About Health, Wealth, and Happiness by Richard H. Thaler and Cass R. Sunstein.

If Obama isn't an old-school Keynesian, what is he? One answer is that he is a behavioralist—the term economists use to describe those who subscribe to the tenets of behavioral economics, an increasingly popular discipline that seeks to marry the insights of psychology to the rigor of economics...One of the reasons this approach has proved so popular is that it appears to provide a center ground between the Friedmanites and the Keynesians, whose intellectual jousting dominated economics for most of the twentieth century...Thaler and Sunstein lay out a number of principles that can be used to encourage better choice-making, and they apply them to various topical issues, including retirement saving, health care, and the environment. In a number of cases, the measures that Thaler and Sunstein recommend are mirrored by proposals in Obama's voluminous policy papers, which can be downloaded from his Web site.

Why Are Conservatives Happier Than Liberals?

Napier and Jost offer an interesting perspective in their article in Psychological Science. Here is an edited excerpt from their general discussion:

In three studies, using nationally representative samples from the United States and nine additional countries, we consistently found that conservatives (or right-wingers) are happier than liberals (or left-wingers). This ideological gap in happiness is not accounted for by demographic differences or by differences in cognitive style (liberals becoming less satisfied with their current situation because of the deleterious effects of rumination and introspection - versus conservatives tending to prefer relatively simple, unambiguous answers to life's questions). We did find, however, that the rationalization of inequality—a core component of conservative ideology — helps to explain why conservatives are, on average, happier than liberals. These findings are consistent with system-justification theory, which posits that viewing the status quo (with its attendant degree of inequality) as fair and legitimate serves a palliative function. The studies suggest that conservatism provides an emotional buffer against the negative hedonic impact of inequality in society.

The relation between political orientation and self-reported happiness as a function of the Gini inequality index, 1974 through 2004.

Only a theory!

Toasting the Joys of Imbibing Properly

Check out this review by Dwight Garner of "EVERYDAY DRINKING - The Distilled Kingsley Amis". The book deals with more than the physical manifestations of a hangover:

...What also urgently needs to be treated, he observed, is the metaphysical hangover — “that ineffable compound of depression, sadness (these two are not the same), anxiety, self-hatred, sense of failure and fear for the future” that looms on the grizzled morning after...Amis recommended, among other things, a course of “hangover reading,” one that “rests on the principle that you must feel worse emotionally before you start to feel better. A good cry is the initial aim."..Thus he suggested beginning with Milton — “My own choice would tend to include the final scene of ‘Paradise Lost,’ ” he wrote, “with what is probably the most poignant moment in all our literature coming at lines 624-6” — before running through Aleksandr Solzhenitsyn, Eric Ambler and, finally, a poulticelike application of light comedies by P. G. Wodehouse and Peter De Vries.

Seeing ourselves / Seeing others - built in errors

Emily Pronin writes a review article in Science Magazine to which my first reaction was "Duh... so what else is new?" But as I looked at it a second time my "who needs to write this down, it is just common sense" reaction began to yield to realizing that the sort of systematic list she offers is useful - way in which intrinsic differences in 1st person (introspective, immersed in our own sensations, emotions, and cognitions) and 3rd person perspectives (extrospective, dominated by what behavior can be observed externally) are guaranteed to lead conflicts in judgements of our own and others behavior. Here are a few clips:

Positive illusions. People tend to have inflated views of themselves and their futures. For example, they think that they are more likely to become wealthy, and less likely to contract contagious diseases, than those around them. This unrealistic optimism partially stems from people's attentional focus on their own (but not others') internal desires and intentions .

Interpersonal knowledge. People overestimate how much they can learn about others from brief encounters such as job interviews (10). At the same time, they think others can get only a glimpse of them from such encounters. As a result, people generally feel they know others better than others know them

Pluralistic ignorance. People often misconstrue the thoughts and motives of others. In cases of "pluralistic ignorance," those misconstruals occur even though others share one's own motives and beliefs and act in the same way as oneself . An example... occurs when an audience of people all succeed in concealing their distraction and boredom during a long lecture and they then assume that they are the only ones not interested and engaged. In another example, college students often forgo trying to make friends with students of other races (even though they would like to be friends) because they interpret those others' lack of trying as indicating lack of interest. Both these examples involve people judging others based on overt behavior (e.g., failing to make social overtures) but themselves based on internal states (e.g., wanting friendship but fearing rejection)

Miscommunications. People often fail miserably in their efforts to communicate. These communication breakdowns (whether they involve negotiating peace agreements, giving driving directions, or navigating romantic relationships) often reflect the fact that people know what they intend or mean to communicate, while others focus on what they actually say. For example, negotiators can fail to outwardly express their interest in cooperating, because their internal awareness of that interest (gained through introspection) blinds them to the fact that the other side sees only their behavior, which often lacks clear signs of that motive

Conformity. People are influenced by those around them (and by the mass media) in everything from fashion tastes to political views; but, they generally deny that and see themselves as alone in a crowd of sheep.

Conclusions. It is almost axiomatic that as long as people are in a position to perceive themselves and to perceive others, differences in those perceptions will exist and will engender disagreement, misunderstanding, and conflict. When people judge themselves based on their good intentions but others based on their less-good behavior (or based on cynical assumptions about human nature), they are likely to feel resentful and disappointed over others' failure to meet them halfway. When people view their own perceptions and beliefs as objective reflections of reality but others' as distorted by bias, they are likely to feel frustrated and angry over others' unwillingness to be fair and reasonable. And, such feelings are likely to breed aggression and conflict.

This picture may sound dismal, but there is hope. Misunderstandings can be averted by those aware of the psychological processes involved in self and social perception. Those individuals can be mindful that it is not only their own behavior that is sensitive to the constraints of the situation, but others' as well. Perhaps this could prompt them to show more charity when others fail to meet expectations. Those individuals also can recognize that others' mistakes and errors may not be the result of conscious malice but rather of unintended influences that those others would themselves decry. And, those individuals might remind themselves that there often is a wide gulf between intention and action, but that it is only reasonable and fair to apply the same standard of judgment to others as to oneself. Following these guidelines would not just be socially charitable— it would also be scientifically informed.

Dan Dennett: Ants, terrorism, and the awesome power of memes

My son Jonathan sent me this link to an engaging talk by Dan Dennett given some time ago. I heard it back then, and think it is worth passing on...

Valse Romantique

Debussy. Someone who listened my recording of this on YouTube asked how to get the sheet music to this piece, and as I sent them the information and listened it again, I decided to relay it on to MindBlog as a bit of relief from the more brainy stuff.

Growing new brain cells enhanced by social contact

From the editor's choice section of the May 30 issue of Science, a suggestion that increased social input from a larger number of other animals enhances the survival of new brain cells in brain areas involved in communication:

Out With the Old, In With the New

Might this adage, which some pundits have claimed as the basis for the vernal electoral calamities that have befallen the Labour Party in the United Kingdom, apply equally forcefully to the turnover of neurons in the brain? Adar et al. have performed a painstaking histological and immunofluorescence accounting of the survival likelihoods of newly born neurons in the brain of the zebra finch, a songbird that serves as an animal model for studying innate and learned influences on vocal communication. They focused on the nidopallium caudale (NC) region because it participates in auditory processing and is activated by social stimuli (other songbirds in this notably social species). By varying the complexity of the social environment, they found that the youngest cells--which had recently migrated from the site of their birth and were still becoming integrated, quite literally, as they established syn-aptic connections with existing NC neurons--were more likely to have survived if the bird had been exposed to a large group of male and female birds; conversely, in birds housed with only one other individual, the survival of older (though still relatively young) cells was enhanced. One interpretation of these data is that an increase in demand--in the form of an upturn in auditory/social inputs needing to be processed--acts as a selective pressure favoring the survival of new recruits.

The neural circuits of free choice

We often face alternatives that we are free to choose between. Planning movements to select an alternative involves several areas in frontal and parietal cortex. Pesaran et al. have looked at activity of single brain neurons in these areas when monkeys are free to choose which movement among several alternatives to make versus when they are following instructions. Correlations between simultaneously recorded spikes and local field potentials in dorsal premotor and parietal reach regions (which are anatomically connected into long-range circuits) increase during the free choice condition. They propose that a decision circuit featuring a sub-population of cells in frontal and parietal cortex may exchange information to coordinate activity between these areas, with cells participating in this decision circuit influencing movement choices by providing a common bias to the selection of movement goals.

The futurist: machines as smart as ourselves

John Tierney does a nice write up of the debate over the ideas of futurist Ray Kurzweil. (I've always thought that Kurzweil was simple proof of the proposition that if you propose any 10 crazy things, one of them will turn out to be right. People remember the correct prophesy, and forget the mistakes.) Still.... the guy has been right on a number of times. Here is part of the discussion of our cognitive/emotional repertoire being bested by machines ( (possibly piggybacked onto our biological hardware). This event is referred to as "the singularity." Kurzweil proposes that:

..by the 2020s we’ll be adding computers to our brains and building machines as smart as ourselves...This serene confidence is not shared by neuroscientists like Vilayanur S. Ramachandran, who discussed future brains with Dr. Kurzweil at the festival. It might be possible to create a thinking, empathetic machine, Dr. Ramachandran said, but it might prove too difficult to reverse-engineer the brain’s circuitry because it evolved so haphazardly...“My colleague Francis Crick used to say that God is a hacker, not an engineer,” Dr. Ramachandran said. “You can do reverse engineering, but you can’t do reverse hacking.”...Dr. Kurzweil’s predictions come under intense scrutiny in the engineering magazine IEEE Spectrum, which devotes its current issue to the Singularity. Some of the experts writing in the issue endorse Dr. Kurzweil’s belief that conscious, intelligent beings can be created, but most think it will take more than a few decades....He is accustomed to this sort of pessimism and readily acknowledges how complicated the brain is. But if experts in neurology and artificial intelligence (or solar energy or medicine) don’t buy his optimistic predictions, he says, that’s because exponential upward curves are so deceptively gradual at first.

“Scientists imagine they’ll keep working at the present pace,” he told me after his speech. “They make linear extrapolations from the past. When it took years to sequence the first 1 percent of the human genome, they worried they’d never finish, but they were right on schedule for an exponential curve. If you reach 1 percent and keep doubling your growth every year, you’ll hit 100 percent in just seven years.”

Dr. Kurzweil is so confident in these curves that he has made a $10,000 bet with Mitch Kapor, the creator of Lotus software. By 2029, Dr. Kurzweil wagers, a computer will pass the Turing Test by carrying on a conversation that is indistinguishable from a human’s.

You should also check out John Horgan's caustic comments on the whole singularity bit in a special IEEE spectrum feature, which ends with:

Let's face it. The singularity is a religious rather than a scientific vision. The science-fiction writer Ken MacLeod has dubbed it “the rapture for nerds,” an allusion to the end-time, when Jesus whisks the faithful to heaven and leaves us sinners behind.

Such yearning for transcendence, whether spiritual or technological, is all too understandable. Both as individuals and as a species, we face deadly serious problems, including terrorism, nuclear proliferation, overpopulation, poverty, famine, environmental degradation, climate change, resource depletion, and AIDS. Engineers and scientists should be helping us face the world's problems and find solutions to them, rather than indulging in escapist, pseudoscientific fantasies like the singularity.