Your bladder and your brain.

Overactive bladder, usually caused by bladder obstruction in males, apparently affects ~17% of the population, towards whom those awful pharmaceutical television adds are directed. Signals arising from bladder or colonic pathology are processed by the cortex and can potentially be expressed as central symptoms (e.g., hyperarousal, attention disorders, anxiety) that occur alongside the visceral pathology. Rickenbacher et al. now show, in a rat model, that bladder obstruction not only botches up the bladder, but also brain regions involved in its regulation.

Neural circuits that allow for reciprocal communication between the brain and viscera are critical for coordinating behavior with visceral activity. At the same time, these circuits are positioned to convey signals from pathologic events occurring in viscera to the brain, thereby providing a structural basis for comorbid central and peripheral symptoms. In the pons, Barrington's nucleus and the norepinephrine (NE) nucleus, locus coeruleus (LC), are integral to a circuit that links the pelvic viscera with the forebrain and coordinates pelvic visceral activity with arousal and behavior. Here, we demonstrate that a prevalent bladder dysfunction, produced by partial obstruction in rat, has an enduring disruptive impact on cortical activity through this circuit. Within 2 weeks of partial bladder obstruction, the activity of LC neurons was tonically elevated. LC hyperactivity was associated with cortical electroencephalographic activation that was characterized by decreased low-frequency (1–3 Hz) activity and prominent theta oscillations (6–8 Hz) that persisted for 4 weeks. Selective lesion of the LC–NE system significantly attenuated the cortical effects. The findings underscore the potential for significant neurobehavioral consequences of bladder disorders, including hyperarousal, sleep disturbances, and disruption of sensorimotor integration, as a result of central noradrenergic hyperactivity. The results further imply that pharmacological manipulation of central NE function may alleviate central sequelae of these visceral disorders.

Applied neuroeconomics - the fear of loss

Bajaj does an interesting writeup of well-known crowd psychological dynamics behind recent "irrational" drops in the stock market. Fear is a more powerful force than greed. Our aversive reaction to losing $1000 is greater than our pleasure at earning the same amount...

fear now seems to rule, with investors often exhibiting a Wall Street version of the fight-or-flight mechanism — selling first, and asking questions later...some analysts are starting to suggest the markets are showing signs of “capitulation” — what happens when even the bullish holdouts, the unflagging optimists, throw up their hands and join the stampede out of the market...To some, signs of capitulation can be read as an indicator that the bottom may be near.

The opposite swing of the cycle is buying at the top of a bubble. I remember during my winter stays in Ft. Lauderdale in 2005 and 2006, every fourth person I chatted with seemed to be a realtor and dinner conversations were dominated by stories about fast profits on flipped condominiums.

Wordwatchers

An article by Wapner points to the work of James Pennebacker and his Wordwatchers blog that is tracking the candidates use of words during the 2008 election. The blog makes fascinating reading. Here is just one clip:

Predicting how they will govern. Most language dimensions that we study are probably better markers of how people will lead than who will vote for them. Some dimensions that are relevant include:

Cognitive complexity. A particularly reliable marker of cognitive complexity is the exclusive word dimension. Exclusive words such as but, except, without, exclude, signal that the speaker is making an effort to distinguish what is in a category and not in a category. Those who use more exclusive words make better grades in college, are more honest in lab studies, and have more nuanced understanding of events and people. Through the primaries until now, Obama has consistently been the highest in exclusive word use and McCain the lowest.

Categorical versus fluid thinking. Some people naturally approach problems by assigning them to categories. Categorical thinking involves the use of articles (a, an, the) and concrete nouns. Men, for example, use articles at much higher rates than women. Fluid thinking involves describing actions and changes, often in more abstract ways. A crude measure of fluid thinking is the use of verbs. Women use verbs more than men.

McCain and Obama could not be more different in their use of articles and verbs. McCain uses verbs at an extremely low rate and articles at a fairly high rate. Obama, on the other hand, is remarkably high in his use of verbs and low in his use of articles. These patterns suggest that McCain’s natural way of understanding the world is to first label the problem and find a way to put it into a pre-existing category. Obama is more likely to define the world as ongoing actions or processes.

Personal and socially connected. Individuals who think about and try to connect with others tend to use more personal pronouns (I, we, you, she, they) than those who are more socially detached. Bush was higher than Kerry or Gore. McCain has consistently been much higher than any other candidate in this election cycle. His use of 1st person singular (I, me, my) is particularly high which often signals an openness and honesty. Obama uses personal pronouns at moderate levels - similar to Hillary Clinton and most other primary candidates of both parties.

Restrained versus impulsive. People vary in the degree to which they act quickly or shoot from the hip versus stand back and consider their options. Over the last few years, some have argued that the use of negations (e.g., no, not, never) indicate a sign of inhibition or constraint. Low use of negations may be linked to impulsiveness. Bush was low in negations whereas Kerry was quite high. Across the election cycle, Obama has consistently been the highest user of negations - suggesting a restrained approach - where as McCain has been the lowest - a more impulsive way of dealing with the world.

MRI of moral emotions while causing harm.

Kédia et al. perform brain imaging of subjects as they imagine harm in several different contexts of subject and victim:

The statement "An agent harms a victim" depicts a situation that triggers moral emotions. Depending on whether the agent and the victim are the self or someone else, it can lead to four different moral emotions: self-anger ("I harm myself"), guilt ("I harm someone"), other-anger ("someone harms me"), and compassion ("someone harms someone"). In order to investigate the neural correlates of these emotions, we examined brain activation patterns elicited by variations in the agent (self vs. other) and the victim (self vs. other) of a harmful action. Twenty-nine healthy participants underwent functional magnetic resonance imaging while imagining being in situations in which they or someone else harmed themselves or someone else. Results indicated that the three emotional conditions associated with the involvement of other, either as agent or victim (guilt, other-anger, and compassion conditions), all activated structures that have been previously associated with the Theory of Mind (ToM, the attribution of mental states to others), namely, the dorsal medial prefrontal cortex, the precuneus, and the bilateral temporo-parietal junction. Moreover, the two conditions in which both the self and other were concerned by the harmful action (guilt and other-anger conditions) recruited emotional structures (i.e., the bilateral amygdala, anterior cingulate, and basal ganglia). These results suggest that specific moral emotions induce different neural activity depending on the extent to which they involve the self and other.

This year's Ig-Noble prize in cognitive science goes to a slime mold

A clip from Steve Nadis' write up in Nature News of this year's Ig-Noble prizes:

Slime moulds exhibit the kind of "contemplative behaviour" that Hamlet is famous for, muses Toshiyuki Nakagaki of Hokkaido University in Japan. ...The slime mold's puzzle-solving ability — Shakespearean or otherwise — is a discovery that is unlikely to change the world, but it won Nakagaki and his colleagues an Ig Nobel Prize for cognitive science last week at the annual event held at Harvard University in Cambridge, Massachusetts. Their research... showed that slime molds looking for food have "the ability to find the minimum-length solution between two points in a labyrinth".

Subsequently, the team has found that molds can find the shortest path between 30–50 points, which is something even supercomputers cannot yet work out. "We can't even check the mold's solution," notes Nakagaki, "but it looks good."

How context can set our emotional reaction to a smell.

Rolls et al. do a piece of work on how selective attention to affective value can alter how our brains process olfactory stimuli:

How does selective attention to affect influence sensory processing? In a functional magnetic resonance imaging investigation, when subjects were instructed to remember and rate the pleasantness of a jasmin odor, activations were greater in the medial orbitofrontal and pregenual cingulate cortex than when subjects were instructed to remember and rate the intensity of the odor. When the subjects were instructed to remember and rate the intensity, activations were greater in the inferior frontal gyrus. These top–down effects occurred not only during odor delivery but started in a preparation period after the instruction before odor delivery, and continued after termination of the odor in a short-term memory period. Thus, depending on the context in which odors are presented and whether affect is relevant, the brain prepares itself, responds to, and remembers an odor differently. These findings show that when attention is paid to affective value, the brain systems engaged to prepare for, represent, and remember a sensory stimulus are different from those engaged when attention is directed to the physical properties of a stimulus such as its intensity. This differential biasing of brain regions engaged in processing a sensory stimulus depending on whether the cognitive demand is for affect-related versus more sensory-related processing may be an important aspect of cognition and attention. This has many implications for understanding the effects not only of olfactory but also of other sensory stimuli.

Autistic people have the visual acuity of hawks.

Ashwin et al. have come up with a fascinating observation during their testing of 15 men with autism-spectrum disorders using the Freiburg Visual Acuity and Contrast Test. They found them to have, on average, 20:7 vision. This means they can see the same detail on an object 20 meters away that a person with average vision can see at 7 meters. Birds of prey have roughly 20:6 vision. What gives these people with autism hawk-like vision isn't known.

Early Fall on Twin Valley Road

Picture of my front yard taken Saturday at my home in Town of Middleton, Wisconsin.

We seek mates that resemble our opposite-sex parents.

The research highlights section of Nature points to work by Bereczkei and his colleagues at the University of Pécs in Hungary who find new evidence linking partner choices to parental appearance. By measuring 14 facial proportions of 312 adults from 52 families, Bereczkei et al. show significant correlations in appearance between young men and their partner's father and young women and their partner's mother. This supports the theory that children are imprinted with their opposite-sex parent's face. The abstract from Proc. Roy. Soc. B:

Former studies have suggested that imprinting-like processes influence the shaping of human mate preferences. In this study, we provide more direct evidence for assessing facial resemblance between subjects' partner and subjects' parents. Fourteen facial proportions were measured on 312 adults belonging to 52 families, and the correlations between family members were compared with those of pairs randomly selected from the population. Spouses proved to be assortatively mated in the majority of measured facial proportions. Significant correlations have been found between the young men and their partner's father (but not his mother), especially on facial proportions belonging to the central area of the face. Women also showed resemblance to their partner's mother (but not to their father) in the facial characteristics of their lower face. Replicating our previous studies, facial photographs of participants were also matched by independent judges who ascribed higher resemblance between partners, and subjects and their partners' opposite-sex parents, compared with controls. Our results support the sexual imprinting hypothesis which states that children shape a mental template of their opposite-sex parents and search for a partner who resembles that perceptual schema. The fact that only the facial metrics of opposite-sex parents showed resemblance to the partner's face tends to rule out the role of familiarity in shaping mating preferences. Our findings also reject several other rival hypotheses. The adaptive value of imprinting-related human mating is discussed, and a hypothesis is made of why different facial areas are involved in males' and females' search for resemblance.

Light exciting our eyes, an intimate picture.

In a former life, I spent 30 years running a laboratory that studies how light is changed into a nerve signal in our eyes. Much of our work centered on the visual pigment rhodopsin, which starts an excitation cascade after its excitation by light by binding to the alpha subunit of a G-protein. I am in awe of new technologies that have, since my work, revealed many of the finer details of this process. Thus I can't resist showing this beautiful graphic from a recent review by Schwartz and Hubbell, describing work by Sheerer et al.


a, Rhodopsin, shown here in its inactivated conformation, is a light-sensing receptor found in cell membranes. It consists of a protein (opsin, green) and a ligand (retinal, pink, also shown in its inactivated conformation). When activated by light, rhodopsin binds to part of an adjacent G protein (binding region in red), triggering a cascade of biological responses. The protein plug (blue) is part of the extracellular domain of opsin, and immobilizes the extracellular transmembrane segments of the receptor. b, Scheerer et al. have determined the activated structure of opsin in complex with the receptor-binding peptide fragment of the G protein (the Galpha peptide). The most notable difference when compared with the inactivated receptor is that transmembrane helix 6 (TM-VI) has moved substantially outward (indicated by the red arrow), thereby creating the binding pocket for the G-protein peptide.

Models to compute and predict our current economic chaos?

Here is an interesting article on the resistance of economic theorists to using modeling approaches that have proven useful in predicting dramatic and sudden transitions. Such models have been successfully applied to predicting heart attacks, epileptic seizures, stock market bubbles, eutrophication of lakes, etc. They are based in part on the observation that variance in an apparent steady state begins to change in predictable ways in advance of large rapid transitions. Modeling the dynamics of a systems of agents by simulating their workings from the bottom up can reveal how instabilities or phase transitions can rise in a system of linked agents by trouble in one of them.

Visualization challenge.

Science Magazine and the National Science Foundation have announced the winners and honorable mentions in the categories of photography, illustration, informational graphics, interactive media, and noninteractive media in this year's International Science & Engineering Visualization Challenge. The first place was this image of diatoms from the Mediterranean off the coast of Italy.

Hope that we might be governed by the head rather than the gut?

Instinctual basis of fury at Wall Street

Benedict Carey has a great article in last Tuesday's NYTimes science section on the evolved psychology of retaliation and forgiveness we share with a large number of other social animal species, particularly with reference to the current public anger at the financial community:

The fury is based in instincts that have had a protective and often stabilizing effect on communities throughout human history. Small, integrated groups in particular often contain members who will stand up and — often at significant risk to themselves — punish cheaters, liars and freeloaders...The catch in this highly sensitive system, most researchers agree, is that it most likely evolved to inoculate small groups against invasive rogues, and not to set right the excesses of a vast and wildly diverse community like the American economy. Some experts believe that Japan’s disastrous delay in bailing out its banks in the early 1990s was caused in part by a collective urge to punish corrupt bankers, and they fear a similar outcome today.

Carey describes a variety of investment game experiments that probe, for example, how our retribution behaviors depend on whether we are being observed by others.

Feeling helpless can enhance our magical thinking

Some experiments very relevant to our current economic chaos are reported by Whitson and Galinsky, who show that when we feel out of control, our need to impose order and rationale is strong enough cause us to see patterns where they do not exist, or conspiracies where there are none.

We present six experiments that tested whether lacking control increases illusory pattern perception, which we define as the identification of a coherent and meaningful interrelationship among a set of random or unrelated stimuli. Participants who lacked control were more likely to perceive a variety of illusory patterns, including seeing images in noise, forming illusory correlations in stock market information, perceiving conspiracies, and developing superstitions. Additionally, we demonstrated that increased pattern perception has a motivational basis by measuring the need for structure directly and showing that the causal link between lack of control and illusory pattern perception is reduced by affirming the self. Although these many disparate forms of pattern perception are typically discussed as separate phenomena, the current results suggest that there is a common motive underlying them.

A college course blog - The Biology of Mind course at the Univ. of Wisconsin

I began a course called "The Biology of Mind" at the University of Wisconsin Madison in 1993, cross listed between the departments of Zoology, Psychology, Anthropology, and Neuroscience. The links to my personal website in the left column of this blog describe that course, whose lecture notes generated the "Biology of Mind" book. On my retirement in 2001, I was very grateful that John Hawks of the UW Anthropology Dept. took over the course, putting his own particular stamp on its contents. He has tried a number of innovations, such as podcasts of the lectures, and now has set up a blog on which students post their writing and commentary. It makes a fascinating read. Here is John's description of the effort:

I am doing a unique experiment with my course this semester, "Biology of Mind." The course has a history of collaborative peer review on writing assignments, and the students do a lot of writing -- students who earn an "A" in the course will be required to produce 10,000 words of written assignments during the semester. In the past, I have used the university's online course system to administer the assignments, and the students have really benefited from their peers' feedback as well as my own.

This semester, I've decided to take it all public. The students are collaborating as before, except this semester they are doing it on a blog. The blog's name is "Biology of Mind", and it has been up and running for a couple of weeks. Right now there are over 200 posts over there, and the number continues to grow.

The students write weekly reviews of papers in psychology, neuroscience, evolutionary biology, philosophy of mind, and naturally anthropology -- a broad scope. Many of the students have been following new research, others have chosen to delve more deeply into the history of one or more fields. In any event, if you're interested in the brain, you may like this site. I think the students (mostly seniors with some graduate students) are producing some nice work, and the site is open for feedback from the public as well.

Our visual long-term memory has a massive storage capacity for object details

In the Sept 23 issue of PNAS Brady et al. make some striking observations on the capacity of our visual memory stores:

One of the major lessons of memory research has been that human memory is fallible, imprecise, and subject to interference. Thus, although observers can remember thousands of images, it is widely assumed that these memories lack detail. Contrary to this assumption, here we show that long-term memory is capable of storing a massive number of objects with details from the image. Participants viewed pictures of 2,500 objects over the course of 5.5 h. Afterward, they were shown pairs of images and indicated which of the two they had seen. The previously viewed item could be paired with either an object from a novel category, an object of the same basic-level category, or the same object in a different state or pose. Performance in each of these conditions was remarkably high (92%, 88%, and 87%, respectively), suggesting that participants successfully maintained detailed representations of thousands of images. These results have implications for cognitive models, in which capacity limitations impose a primary computational constraint (e.g., models of object recognition), and pose a challenge to neural models of memory storage and retrieval, which must be able to account for such a large and detailed storage capacity.


Figure: Example test pairs presented during the two-alternative forced-choice task for all three conditions (novel, exemplar, and state). The number of observers reporting the correct item is shown for each of the depicted pairs.

How do you like your coffee?

A cute piece by Katherine Sanderson from the Oct. 1 Nature:

The floating fractal (top, left) is formed 90 seconds after a drop of instant coffee falls into a cup of milk.

Coffee is heavier than milk and the battle between gravity and surface tension plays out at the boundary between the two liquids. The coffee falls vertically through the milk (bottom, left, with water replacing milk for ease of viewing), and the fractal pattern emerges.

The pattern constantly shifts as parts of it are sucked into the milk, producing a fractal structure with the same dimension as a Sierpi´nski carpet — formed when a square is cut into nine identical squares; the central square is removed; and the procedure is repeated with the remaining eight squares and so on infinitely.

Michiko Shimokawa and Shonosuke Ohta, fluid scientists at Kyushu University in Fukuoka City, Japan, say that it is the first time this kind of fractal has been shown experimentally (http://www.arxiv.org/abs/0809.2458), and they managed to recreate the process using a magnetic liquid instead of coffee (far right).

A Grieg Air for Monday morning

Yesterday was a rainy afternoon at my home on Twin Valley Road in Middleton Wisconsin, so I decided to a video recording of a relatively tranquil, lyrical piece by Edvard Grieg that I enjoy playing - the Air from his Holberg Suite.

Political Attitudes Vary with Physiological Traits

Not exactly surprising, but fascinating never the less, from Oxley et al.

Although political views have been thought to arise largely from individuals' experiences, recent research suggests that they may have a biological basis. We present evidence that variations in political attitudes correlate with physiological traits. In a group of 46 adult participants with strong political beliefs, individuals with measurably lower physical sensitivities to sudden noises and threatening visual images were more likely to support foreign aid, liberal immigration policies, pacifism, and gun control, whereas individuals displaying measurably higher physiological reactions to those same stimuli were more likely to favor defense spending, capital punishment, patriotism, and the Iraq War. Thus, the degree to which individuals are physiologically responsive to threat appears to indicate the degree to which they advocate policies that protect the existing social structure from both external (outgroup) and internal (norm-violator) threats.