Human pheromone (sexual attractant) candidates act differently on areas of the hypothalamus regulating sexual behavior in gay men and lesbian women.

I could recast the wording, but think this abstract of a recent paper from Savic and collaborators, published in Proc. Nat. Acad. Sci., makes the point. Links are to the two relevant articles. Yet another antidote to anti-gay "homosexuality is a choice" conservatives who want to deny the biological basis of homosexualtiy

"The progesterone derivative 4,16-androstadien-3-one (AND) and the estrogen-like steroid estra-1,3,5(10),16-tetraen-3-ol (EST) are candidate compounds for human pheromones. In previous positron emission tomography studies, we found that smelling AND and EST activated regions primarily incorporating the sexually dimorphic nuclei of the anterior hypothalamus, that this activation was differentiated with respect to sex and compound, and that homosexual men processed AND congruently with heterosexual women rather than heterosexual men. These observations indicate involvement of the anterior hypothalamus in physiological processes related to sexual orientation in humans. We expand the information on this issue in the present study by performing identical positron emission tomography experiments on 12 lesbian women. In contrast to heterosexual women, lesbian women processed AND stimuli by the olfactory networks and not the anterior hypothalamus. Furthermore, when smelling EST, they partly shared activation of the anterior hypothalamus with heterosexual men. These data support our previous results about differentiated processing of pheromone-like stimuli in humans and further strengthen the notion of a coupling between hypothalamic neuronal circuits and sexual preferences."

The Attention Revolution

This is the title of a book by Allan Wallace which gives systematic instruction in building our capacity for calm and simple attention. For most of us, life is a series of constant distractions and multitasking - many of us move well towards the clinical definition of Attention Deficit Hyperactivity Disorder. Drugs such as ritalin that calm and focus the mind are widely used.

Wallace presents meditative techniques developed by contemplatives for millennia that have attentional stability as their core element. They enhance the capacity for attention, and strengthen this mental ability as as we might strengthen our muscles through physical exercise. Their goal is to counter the oscillation between the restlessness and boredom, or between the agitation and dullness, of the untrained mind. I'm providing a longer than usual blog posting on this book, abstracting points from the book that seem most useful or interesting to me.

Wallace uses a 10- step framework or path provided by the 8th century Indian Buddhist contemplative Kamalashila in his classic work "Stages of Meditation." He makes interesting comparisons of the different approaches of several Buddhist traditions. The early steps emphasize mindfulness of breathing with relaxation, stability, and vividness. The practice of focused attention is essentially "non-multitaking"

Meditation is a balancing act between attention and relaxation. While sustaining attention on a focused object such as breathing there is no effort to block distraction that arise. They are simply noted and released to return to the object of attention. During what Wallace terms 'coarse excitation' the object is completely displaced from awareness for a period, while in 'subtle excitation' the object is held in mind while other thoughts, feelings and emotions are noted in the mind's periphery (like losing your radio station completely versus having it obscured by static or drift). In 'coarse laxity' attention detaches from the object and sinks into a spaced out vacancy, like having your radio reception fade out. In 'subtle laxity' attention remains but is of low intensity and vividness.

A quote from Wallace: "While the main force of your awareness is directed to the meditation object with mindfulness, this needs to be supported with the faculty of introspection, which allows for the quality control of attention, enabling you to swiftly note when the mind has fallen into either excitation or laxity. As soon as you detect either imbalance, take the necessary steps to remedy it. Your first antidote to excitation is to relax more deeply; to counteract laxity, arouse your attention."

Mindfulness in modern psychological accounts, and also the Vipassana (contemplative ingiths) tradition of Theravada Buddhism (Southeast Asia), refers to the moment to moment awareness of contents passing through the mind that does not label or categorize experiences. This differs from the Indo-Tibetan Buddhist version that "characterizes mindfulness as bearing in mind the object of attention, the state of not forgetting, not being distracted, and not floating." (If I read the text correctly, what the Indo-Tibetan Buddhist practice calls 'introspection' is similar to the mindfullness of the Theravada Buddhist practice.. indeed, yes, see page 120). Both are similar to what psychologists call 'metacognition.' The central point seems to be that one has the goal of keeping in mind a single object, such as an aspect of breathing, and then notes perturbations of that process by transient excitation or laxity. The mind watches itself.

The fifth step in the 10 step framework moves away attention to breath and to the practice of "settling the mind in its natural state," that is, without the distraction of it being carried away by thoughts and sense impressions. Eyes are left open to allow the conceptually superimposed demarcation between inner and outer to erode. Thoughts come and go, but because you are not distracted by them and don't grasp onto them, your awareness remains still. This is called the fusion of stillness and movement. This practice strengthens the psychological immune system, so that previously upsetting thoughts are now handled with greater composure.

As lapses between thoughts increase in length, awareness increasingly hovers in a kind of empty space or vacuum devoid of personhood. (My own experience leads me to feel that that this is the intuitive experience of our brain's 'self-generator' in a more quiescent state, with the generation of emotions or self models greatly attentuated). The loss of the normal sense of who you are can cause fear and dread, but this can pass as one realizes "there is no danger in the empty, luminous space of awareness. You have nothing to lose but your false sense of an independent, controlling ego." (cf. my "I-Illusion" essay on this website.)

In both the Theravada and the Indo-Tibetan traditions of Buddhism, cultivation of bare attention or concentration combined with introspection or mindfulness leads to experiential realization of the ground state of the psyche, "the ground of becoming," which supports all kinds of mental activities and sensory perceptions, as the root of a tree sustains the trunk, branches, and leaves. The "natural state" of the mind, according to Buddhist contemplatives, is bliss, luminosity, and nonconceptuality. Wallace makes descriptions of bliss and luminosity that suggest to me correlations with parasympathetic (mellowing out) versus sympathetic (arousal) activity in our autonomic nervous systems.

There is an enduring debate among the schools of Tibetan Buddhism over the nature of primordial consciousness - whether the 'enlightened consciousness' is something that is cultivated or something that is merely uncovered. In either case, it is accessed by first refining one's powers of attention, and then using that ability as an aid in exploring and purifying the mind through first person observation.

Shamatha is the tenth and final stage of attentional development, and can be reached at will by experienced practioners. Wallace quotes Dudjom Lingpa: "Eventually all coarse and subtle thoughts will be calmed int he empty expanse of the essential nature of your mind. You will become still in an unfluctuating state, in which you will experience joy like the warmth of a fire, clarity like the dawn, and non-conceptuality like an ocean unmoved by waves."

Sounds good to me. Guess I'm not quite there yet!!

Autistic children insensitive to emotional expressions in others also show decreased activity in their brain's 'mirror neuron' system.

Systems of mirror neurons in our brains are active during our actions and feelings and also when we observe those actions or feelings in others (see the Feb. 9 posting in this blog). Dapretto et al. now show that mirror neuron system activity during observation of emotional expressions in typically developing children is much greater than in autistic children. This suggests that a dysfunctional mirror neuron system may underlie the social deficits observed in autism.

Legend: Mirror neuron system activity during observation of emotional expressions. The right pars opercularis showed significantly greater activity in typically developing children than in children with ASD (t > 1.83, P < 0.05, small volume corrected). Credit: Nature Neuroscience

Why don't we choose what makes us happy?

Hsee and Hastie provide an interesting review of this issue in Trends in Cognitive Sciences. Numerous studies prove that people systematically fail to predict or choose what maximizes their happiness. This casts doubt on the validity of social policies that assume that people can act in their own best interest in choosing between health providers, retirement plans, public offices, multiple commercial products, etc.

There are two central reasons for this failure: predictions biases and failures to follow predictions. Prediction biases occur because predictors do not full appreciate the differences between the state of prediction and the state of experience. One might be more or less hungry, rested, or sexually aroused while predicting versus experiencing (projection bias). Memory, beliefs, number of distinctions being made can also lead to bias errors. Failures to follow predictions of what will generate the greatest overall happiness can occur when instead the choice is made with the greatest immediate appeal (impulsivity), that is easy to justify (lay rationalism), that yields the greatest token reward such as money (medium maximization), or that fits choice rules (lay rationalism).

Cooperation, Punishment, and the Evolution of Human Institutions

This is the title of a review by Henrich of studies on how human cooperations and sanctions might have evolved, which specifically cites a paper by Gurerk et al in Science. People are offered the choice of two institutions in which individuals make voluntary contributions with the total then being equally distributed among all. Participants know what was contributed by others. In the first, individuals who do not contribute still receive an equal share of the total collected but no sanctions are applied to poor contributors. In the second, participants can choose to penalize slackers at some cost to themselves. The authors show "that a sanctioning institution is the undisputed winner in a competition with a sanction-free institution. Despite initial aversion, the entire population migrates successively to the sanctioning institution and strongly cooperates, whereas the sanction-free society becomes fully depopulated. The findings demonstrate the competitive advantage of sanctioning institutions and exemplify the emergence and manifestation of social order driven by institutional selection."

Stressing out or Chilling out changes how our genes are expressed in an immediate and dynamic way.

Bittman et al., in "Recreational music-making modulates the stress response and alters individual gene expression," have followed the expression of 45 genes associated with stress, immune, and inflammation responses after one hour of a stress induction protocol (solving a 500 piece puzzle while being told at 10 minute intervals that other subjects were doing better). Subjects were then split into three groups for a further hour: one continued the stressful situation, the second read a newspaper, and the third participated in a recreational music making session (the clavinova connection). In the latter group 19 genes expression changes caused by stress were significantly reversed. None were reversed in the group continuing the stress test and 6 reversed in the group just reading a newspaper.

The brain finds pleasure in novelty.......

Humans are informavores, and derive pleasure from novel auditory and visual stimulation. Biederman and Vessel note that novel visual images rated most highly by observed also cause stronger activation of the parahippocampal gyrus, where they are interpreted in the context of stored memories, and this activation fades as the same image is repeated and becomes more familiar. This area is also rich in mu-opioid receptors (involved in pleasure and reward, and activated by morphine and endogenous morphine-like substances - endomorphins - in the brain). They suggest that the rate of endomorphin release in the parahippocampal cortex partially underlies our human preference for experiences that are both novel and richly interpretable.




Legend: Visual information flows from the primary visual cortex (bottom, orange) towards parahippocampal regions where it is interpreted (middle, purple). Credit: American Scientist.

Religion as a Natural Phenomenon - More on Dennett's Book "Breaking the Spell"

This book has now received extensive and varying reviews in both popular (New York Times Book Review, The New Yorker) and scientific (Science, Nature) magazines. Dennett and others argue that religion appeared because groups of humans that developed religious rituals replicated themselves more successfully than those that did not. The fact that human brains developed both self awareness and awareness that others are aware may have led us to have hyperactive agent detection capabilities that not only protect us, but also lead us to believe that rocks and trees are imbued with intentional minds or spirits. This is animism, which led to polytheism, and eventually monotheism. The values of religion to evolutionary fitness could include (from Shermer's review in Science) mythmaking (to explain the dangers and meaning of the natural world), morality (to regulate pro- and anti-social behavior), sociality (within-group amity and between-group enmity), and redemption and resurrection (forgiveness in this life and immortality in the next life). Dennett points out how US mega-churches cater to people's needs - they have a product that opens the wallets of their members as well as moral and social values "that lead to anti-abortion fanaticism, capital punishment, excoriation of gays and lesbians, and dangerous military excursions in the Near East." (from Ruse's Nature review). The religion "meme" continues to grow in the vast majority of humans alive today. (The term "meme" , coined by Richard Dawkins, refers to thoughts, songs, or rituals that replicate and propagate from one human mind to another. The idea is that memes underlie cultural evolution just as genes underlie biological evolution.)

The pleasures and pains of information about the future.

Berns et al show that regions of the brain activated by pain are also activated by the anticipation of pain, and that some experimental subjects choose to receive an anticipated electrical shock sooner rather than later, to "get it over with," even when told the shock will be larger than the anticipated one.

It is also known that brain regions activated by pleasure are also activated by anticipation of pleasure, and subjects will frequently defer a desired outcome to prolong the pleasure of anticipation. These real behaviors are the exact opposite of those in many economic models, which assume that people will defer negative outcomes and accelerated desired ones.

A review by Loewenstein highlights varied studies on the utility of information, and how emotional factors lead people to desire or avoid it.

Two ways of knowing the minds of others

Mitchell's laboratory at Harvard has shed light on two traditionally opposed hypotheses about how we infer the mental states of others. Simulation theory posits that we use our own experience to infer the experience of others. It is known that when we observe actions and emotions in others, regions in our own brain that would generate those actions or emotions become active and mirror what we are observing. Theory of mind, on the other hand, holds that we use abstract rules about how people behave to infer the mental states of others.

Mitchell et al used functional neuroimaging to examine how perceivers make mental state inferences when such self-other overlap can be assumed (when the other is similar to oneself) and when it cannot (when the other is dissimilar from oneself). "We observed a double dissociation such that mentalizing about a similar other engaged a region of ventral mPFC (medial prefrontal cortex) linked to self-referential thought, whereas mentalizing about a dissimilar other engaged a more dorsal subregion of mPFC. "

Legend: Division of labor. Different regions of prefrontal cortex fire up when people ponder the mental states of others perceived as similar (blue) or dissimilar (red) to themselves. Credit: Jason Mitchell.

"The overlap between judgments of self and similar others suggests the plausibility of "simulation" accounts of social cognition, which posit that perceivers can use knowledge about themselves to infer the mental states of others." And, the activation of dorsal mPFC during thinking about dissimilar others might correspond to more rule bound theory of mind operations.

The good, the bad and the amygdala

This is the title of a brief review by Ruth Williams in Nature Reviews Neuroscience pointing out an article by Paton et al. that demonstrates that in monkeys the values associated with visual stimuli are represented in the amygdala, a structure involved in reinforcement learning. Individual amygdala neurons apparently code for either "good" or "bad" . When a visual stimulus that was initially paired with a positive reward was switched to being paired with a negative reward, more that half of the responding amygdala neurons showed a switch in activity that correlated with changes in behavior, and some individual neurons showed value-specific activity. This work further confirms that the amygdala is a key brain structure in the representation of the learned value of visual stimuli.

Dolphins have discovered "names" of the sort we use.

It has been known since the 1960s that dolphins develop individually distinctive signature whistles that they use to maintain group cohesion. Now Janik et al have shown that dolphins extract identity information from signature whistles even after all voice features have been removed from the signal. The synthesized whistles retained the distinct variation in frequency over time of an individual's signal, but removed other characteristics like harmonics, dynamics, and extraneous noises such as the clicking sounds that dolphins can also make. When exposed to the artificial whistle modeled after that of a related group member, other dolphins turned towards the sound. Excerpts from Henry Fountain's comments on this work in the New York Times: "To draw an analogy to humans, the frequency modulation pattern is the "language," and the dolphins could identify it regardless of the whistle's "voice." And a quote from Janik: "Most other animals appear to rely on the sound of the voice, rather than any coded information, for recognition. But parrots may have similar "signature" calls, which shows that you can do this if you have a huge brain, but you can also do this if you have a small one."

Men and Women react differently to sniffing a social hormone - aggressively versus friendly

Thompson et al have found that a peptide influencing social behaviors in numerous species, Arginine vasopressin (AVP), causes different behaviors in men and women when administered intranasally with an inhaler. In men, AVP stimulates agonistic (i.e. combative) facial motor patterns in response to the faces of unfamiliar men and decreases perceptions of the friendliness of those faces. In contrast, in women, AVP stimulates affiliative facial motor patterns in response to the faces of unfamiliar women and increases perceptions of the friendliness of those faces. AVP also affected autonomic responsiveness to threatening faces and increased anxiety, which may underlie which may underlie the peptide's sex-specific effects on social communication by promoting different social strategies in response to stress in the sexes. The authors note; "Because intranasal AVP administration crosses the blood-brain barrier and, at the dose we used, directly affects central processes, whereas peripheral elevations do not, we argue that the effects we observed were likely centrally mediated, either through CSF-signaling mechanisms or by means of diffusion into discrete brain areas. Thus, our results support the hypothesis that central AVP's ability to influence social communication processes, a conserved trait of AVT and AVP in vertebrates, has been retained in humans."

Recursion in vocalization not unique to humans

Several years ago Marc Hauser, Noam Chomsky and Tecumseh Fitch published an influential paper that speculated that recursion, or self embedding, might be the one aspect of language that is clearly unique to humans. Gentner et al have now shown that the European starling can be trained to recognize complex recursive grammars. A review by Marcus suggest that "the abstract computational capacity of language may consist not so much of a single innovation as a novel evolutionary reconfiguration of many.. ancestral cognitive components, genetically rejigged into a new whole. Contemporary research suggests that the human brain contains few if any unique neuronal types, and few if any genes lack a significant ancestral precedent."

Stumbling on Happiness

This is the title of a new book by Harvard psychologist Daniel Gilbert. One quote from the N.Y. Times review by Scott Stossel in the May 7 book review section: "When we have an experience..on successive occasions, we quickly begin to adapt to it, and the experience yields less pleasure each time...Psychologists call this habituation, economists call it declining marginal utility, and the rest of us call it marriage."

His basic theme is that humans are very bad at predicting what will make them happy. Things we expect to give us joy make us less happy than we think; and things that we dread make us less unhappy, especially after some time has passed. There is a "psychological immune system" that starts up after big negative events.

From the book: "How do we manage to think of ourselves as great drivers, talented lovers and brilliant chefs when the facts of our lives include a pathetic parade of dented cars, disappointed partners and deflated souffles?...The answer is simple: We cook the facts." What gets us through life is just the right amount of delusion, enough to fool us into feeling relatively good about ourselves. Interestingly, the clinically depressed seem less susceptible to these basic cognitive errors.

A new brain module for understanding whole words

While it has been known that rapidly comprehending whole words activates an area called the visual word form area (VWFA), the same area is also activated by faces and objects. Gaillard et al have now shown that this area is indispensable for reading whole words, but not faces and objects. In an operation for severe epilespy, they removed a small area near the VWFA. The patient now required 900 milliseconds rather than 600 milliseconds to recognize a three letter word, suggesting a transition from reading the whole word to reading letter by letter.

What is curious is that a task invented only about 6,000 years ago, understanding whole words as entities instead of letter by letter, apparently requires a dedicated brain area. Since this is a very short time for genetic changes that might enable such an area, it seems more likely that this specialzed area forms during language development in each individual as a solution to the problem of rapidly processing written text.

The Paomnnehal Pweor Of The Hmuan Mnid

I cluod aulaclty uesdnatnrd waht I was rdgnieg.

Aoccdrnig to a rscheearch at Cmabrigde Uinervtisy, it deosn't mttaer in waht oredr the ltteers in a wrod are, the olny iprmoatnt tihng is taht the frist and lsat ltteer be in the rghit pclae. The rset can be a taotl mses and you can sitll raed it wouthit porbelm. Tihs is bcuseae the huamn mnid deos not raed ervey lteter by istlef, but the wrod as a wlohe.

Amzanighuh?

Inhibiting Negative Emotions - Opps!, A simple story evaporates

Numerous studies from Davidson's laboratory and others have shown that deliberately suppressing negative affect correlates with increased activity in the prefrontal cortex (and vice versa). The idea has been that the more modern thinking and interpreting prefrontal cortex feeds down to inhibit the amygdala, the center of emotional reactivity in our more primitive mammalian brain. Most of this work was done on college students or younger people. Urry et al now find that older subjects, 62-64 years of age, can suppress negative affect without a corresponding increase in prefrontal activation. In a supplement they offer reasons for the discrepancy. It is very hard to walk away with any kind of clean message now, a situation not helped by the fact that this is one of the most poorly written jargon laden papers I have ever tried to wade through. The senior authors should have paid more attention to what they were putting their name on.

Brain's Reward Pathway Involved in Mood Disorders

A recent Science article by Berton et. al. shows that long lasting fearful and withdrawal behaviors that are induced in mice by bullying and intimidation are enabled by a nerve growth factor (BDNF, brain derived neurotrophic factor) acting in the mesolimbic dopamine reward pathway in the brain. When a genetic trick is used to knock out DBNT production in just this area, mice are no longer intimidated by bullies. Elsewhere in the brain BDNF is associated with an opposite effect, antidepressant actions. The authors point out that the brain's reward system has been slighted in research on emotional disorders, even though the inability to experience rewarding feelings is a hallmark of depression and emotional withdrawal.

The Self-Help Scam

In the May 2006 issue of The Scientific American, Michael Shermer (publisher of Skeptic magazine) argues that the Self-Help and Actualization Movement (SHAM), an $8.5 billion-a-year business, is a scam. He notes the recent book by Steve Salerno, "SHAM: How the Self-Help Movement Made America Helpless (Crown Publishing Group, 2005). There is an eighteen week rule: the most likely customer for a self help book is someone who bought a similar book with the preceeding eighteen months. If the books worked, why would one need further help? A bulletproof shield surrounds SHAM: if your life does not get better, it is your fault, your thoughts were not positive enough. The solution? More of the same self-help. SHAM books market a clever mix of victimization and empowerment. We are all victims of our demonic "inner children" replaying negative tapes. Redemption comes from empowering yourself with the new "life script" offered by the self-help book or by the masters themselves at prices ranging from $500 to $6,000. Unfortunately there is no evidence that any of the SHAM techniques is better than doing something else or even doing nothing (the same problem is faced by virtually all therapies).