Our psychological immune system

In a previous post I mentioned a review of the book by Daniel Gilbert (Harvard Psychology Department ) "Stumbling on Happiness". It is a wonderful read, hysterically funny in many places. Solid science with excellent notes on original sources. Here are some quotes from Chapter 8 "Paradise Glossed." I'm probably going to do additional posts on this book.

"Our experience of the world is a mixture of stark reality and comforting illusion. We can't spare either. If we were to experience the world exactly as it is, we'd be too depressed to get out of bed in the morning, but if we were to experience the world exactly as we want it to be, we'd be too deluded to find our slippers...we might think of people as having a psychological immune system that defends the mind against unhappiness in much the same way that the physical immune system defends the body against illness. This metaphor is unusually appropriate. For example, the physical immune system must strike a balance between two competing needs: the need to recognize and destroy foreign invaders such as viruses and bacteria, and the need to recognize and respect the body's own cells. If the physical immune system is hypoactive, it fails to defend the body against micropredators and we are stricken with infections; but if the physical immune system is hyperactive, it mistakenly defends the body against itself and we are stricken with autoimmune disease.... A healthy physical immune system must balance its competing needs and find a way to defend us well - but not too well.... "

"Analogously, when we face the pain of rejection, loss, misfortune, and failure, the psychological immune system must not defend us too well ("I'm perfect and everyone is against me") and must not fail to defend us well enough ("I'm a loser and I ought to be dead"). A healthy psychological immune system strikes a balance that allows us to feel good enough to cope with our situation but bad enough to do something about it ("Yeah, that was a lousy performance and I feel crummy about it, but I've got enough confidence to give it a second shot."). We need to be defended, not defenseless or defensive, and thus our minds naturally look for the best view of things while simultaneously insisting that those views stick reasonably closely to the facts."

At the chapter end, after a further section on how we conspire to see mostly what we want to see; "To ensure that our views are positive, our eye looks for what our brain wants. The conspiracy between these two servants allows us to live at the fulcrum of stark reality and comforting illusion."

The brain during normal awareness, absence Seizures, and the vegetative state

A review by Laureys in Trends in Cognitive Sciences (Volume 9, Issue 12, December 2005, Pages 556-559) notes the brain correlates of the different levels of consciousness summarized in this figure:



A variety of studies have shown declines in the content and level of consciousness correlate with activity decreases in frontal and parietal regions of the brain. During absence seizures and sleepwalking, during which partially preserved arousal and behaviors such as walking are preserved in the absence of self awareness, frontal and parietal association cortices are deactivated.

Left Brain and Right Brain in the regulation of our subjective feelings.

There is increasing evidence that an the insula areas of our left and right cerebral cortices process higher order re-representations of homeostatic (body regulatory) senses which are sent to prefrontal cortical areas and are the site of our subjective feelings about our bodies. (i.e., sensory information about our bodies from sympathetic and parasympathetic systems feeds to the insula and then on to the prefrontal cortex).

I'm including here quotes from a recent proposal by Craig in Trends in Cognitives Sciences (vol 9,pg. 566,2005) that tries to link many disparate threads to cast an integrated model of how basic regulatory levels of energy expenditure or storage regulated by the sympathetic and parasympathetic nervous systems though out our bodies connect to our higher levels of frontal lobe cognition. His proposal "highlights emerging evidence in support of a direct neuroanatomical relationship in the human forebrain between emotion and homeostasis that mirrors the asymmetric opponent management of energy acquisition and utilization by the autonomic nervous system."

"Recent neurobiological studies using anatomical, neurological, and functional imaging methods indicate that subjectively experienced feelings and emotions might be based on higher-order re-representations of homeostatic afferent (sensory) activity in the human forebrain, and it is particularly noteworthy that such evidence indicates a strong pattern of lateralization. Further, there is a comparable pattern of lateralization evident for the cortical control of cardiac activity, and this can be directly related to left/right asymmetry in the opposing parasympathetic and sympathetic components of the peripheral autonomic nervous system. The confluence of these strikingly parallel asymmetries suggests a homeostatic neuroanatomical model of emotional asymmetry, in which the left forebrain is associated predominantly with parasympathetic activity, and thus with nourishment, safety, positive affect, approach (appetitive) behavior, and group-oriented (affiliative) emotions, while the right forebrain is associated predominantly with sympathetic activity, and thus with arousal, danger, negative affect, withdrawal (aversive) behavior, and individual-oriented (survival) emotions. In the model I am proposing, management of physical and mental (meaning neural) energy is the salient organizational motif, such that energy enrichment is associated with the left forebrain and energy expenditure is associated with the right forebrain, consistent with the respective roles of the parasympathetic and sympathetic efferent systems. The autonomic principle of coordinated opponent interactions between the two hemispheres could provide a fundamental management process."

Figure: Imaging activity in the insula. Credit Univ. of Cambridge Center for Speech and Language.

We need our orbitofrontal cortex to make intelligent choices. Its individual cells code for value.

Credit: Ann Thomson, Nature Neuroscience

Damage to the part of our frontal lobes just above our eyes, the orbitofrontal cortex, can damage our ability to subjectively determine the value of various choices. There are several clinical cases in which strokes or removal of tumors from this area have caused individuals to start making catastrophic personal choices, even while maintaining normal language, memory, intelligence and motor abilities. Padoa_Schioppa and Assad have now actually recorded from individual cells in this area in the monkey's brain while the monkey is making value choices (such as choosing between juices of different flavor, sweetness, or volume). They find that neurons in the orbitofrontal cortex encode the value of offered and chosen goods, independent of the location of the goods or the movements required to get them. In other areas of the brain value modulates choice relative to sensory or motor processes. Thus this part of the brain seems to be involved in assigning value, making economic choices between goods rather than choice between actions.

Apes plan ahead for the future! - yet another 'unique human trait' bites the dust.

Chimpanzees in a primate center in Leipzig, Germany, learned to use an object as a tool to obtain grapes from an apparatus in a test room Mulchay et al. then presented the chimps with a number of objects what would make either suitable or unsuitable tools for extracting the grapes and let the chimps take the tool first to a waiting room, and then back to the waiting room to get the reward, either an hour later or the next morning. Most chimps selected and then returned with a suitable tool. This indicates that at least a precursor skill for planning for the future evolved in the great apes before 14 million years ago, when all extant great ape species shared a common ancestor.

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.