An interesting primate

I recently learned about slow lorises, a primate that I had never heard of before. The diversity of species continues to amaze! These particular primates are unfortunately endangered but they have some very endearing, human-like behaviors:

It is nice how YouTube can be both educational and entertaining!

Longitudinal study on happiness and success

The Atlantic‘s Joshua Shenk has a fascinating story about a long-running study, started in the 1930s (!), that attempts to discern what makes people happy in life. The study has collected extensive data on subjects over a 70 year period. I couldn’t stop reading the article… what an amazing dataset. But, before I say more about that, here is Shenk’s synopsis of a single case file (ie. actual data) from the study:

Case No. 158

An attractive, amiable boy from a working-class background, you struck the study staff as happy, stable, and sociable. “My general impression is that this boy will be normal and well-adjusted—rather dynamic and positive,” the psychiatrist reported.

After college, you got an advanced degree and began to climb the rungs in your profession. You married a terrific girl, and you two played piano together for fun. You eventually had five kids. Asked about your work in education, you said, “What I am doing is not work; it is fun. I know what real work is like.” Asked at age 25 whether you had “any personal problems or emotional conflicts (including sexual),” you answered, “No … As Plato or some of your psychiatrists might say, I am at present just ‘riding the wave.’” You come across in your files as smart, sensible, and hard-working. “This man has always kept a pleasant face turned toward the world,” Dr. Heath noted after a visit from you in 1949. From your questionnaire that year, he got “a hint … that everything has not been satisfactory” at your job. But you had no complaints. After interviewing you at your 25th reunion, Dr. Vaillant described you as a “solid guy.”

Two years later, at 49, you were running a major institution. The strain showed immediately. Asked for a brief job description, you wrote: “RESPONSIBLE (BLAMED) FOR EVERYTHING.” You added, “No matter what I do … I am wrong … We are just ducks in a shooting gallery. Any duck will do.” On top of your job troubles, your mother had a stroke, and your wife developed cancer. Three years after you started the job, you resigned before you could be fired. You were 52, and you never worked again. (You kept afloat with income from stock in a company you’d done work for, and a pension.)

Seven years later, Dr. Vaillant spoke with you: “He continued to obsess … about his resignation,” he wrote. Four years later, you returned to the subject “in an obsessional way.” Four years later still: “It seemed as if all time had stopped” for you when you resigned. “At times I wondered if there was anybody home,” Dr. Vaillant wrote. Your first wife had died, and you treated your second wife “like a familiar old shoe,” he said.

But you called yourself happy. When you were 74, the questionnaire asked: “Have you ever felt so down in the dumps that nothing could cheer you up?” and gave the options “All of the time, some of the time, none of the time.” You circled “None of the time.” “Have you felt calm and peaceful?” You circled “All of the time.” Two years later, the study asked: “Many people hope to become wiser as they grow older. Would you give an example of a bit of wisdom you acquired and how you came by it?” You wrote that, after having polio and diphtheria in childhood, “I never gave up hope that I could compete again. Never expect you will fail. Don’t cry, if you do.”

What fascinates me is the absolute novelty of this kind of data. Normally, when someone relates their “life story,” we willingly participate in something of a shared lie. Both listener and story-teller know that the “life story” is being told in hindsight: Memory is not perfect and humans sometimes (often, perhaps) add meaning and create unifying themes in stories where they may be none. We emphasize the good parts and try to forget the not-so-good parts. In a sense, history recounted is never truly veridical but instead tainted with everything that happened after. Which is precisely why the availability of an objective history than spans an entire lifetime (or, as objective as possible) of both a qualitative (interview) and quantitative (medical) nature is so novel.

As you might expect, the data is confusing and hard conclusions are not easy to come by. There are however some tangible factors that seemed to correlate/predict success in life, which I’ve included after the jump. Continue reading

Mouse dressage

Neuroscientists often use mouse models to understand learning and neural disease. Much of our understanding of mammalian biology comes from these amazing animals. It is commonly said that highly inbred lab mice are unintelligent. But is it true for wild mice too? In a talk last week at Harvard, Karl Svoboda referred to this fascinating YouTube video showing a mouse trained to complete an obstacle course:

Other training videos from the same trainer are available along with an official website with interesting tips about mouse training. Perhaps highly inbred lab mice are unable to replicate such feats but it is amazing to see in what detail this trainer understands mouse behavior and development:

An absolute necessity for any pet training is to understand the animal’s needs and to know about its generic behaviour, since appropriate animal training is only based on certain natural habits. For mouse agility, this means e.g. their great spatial orientation abilities and spatial memory which is worth bringing to light by relevant trick training. In nature, mice always prefer the familiar (= safe) route to their feeding site, no matter if it’s a long way round. This is also the reason why mice are unbeatable in maze tests – and a mouse agility course is nothing else than a maze without walls!
But many owners forget that if you expect your pet to show some natural habits and abilities, first and foremost the husbandry has to be species-appropriate. If your mice have to live in a small ground level cage, their three-dimensional consciousness and orientation abilities will surely be stunted or never fully develop.

Evidence of similar linguistic capabilities in Neaderthals

Apparently, in a few years, we will be able to bring Neaderthals back to life with the complete Neaderthal genome [NYT]. Currently, there is good sequence data available over 63% of the genome. (I’m amazed that, given fragmented DNA from bone, Neanderthal sequence can be distinguished from human DNA contamination but perhaps this problem is solved by having high enough coverage/multiple fragments of the same region.)

Also, it looks like Neanderthals share the FOXP2 variant that humans have:

Archaeologists have long debated whether Neanderthals could speak, and they have eagerly awaited Dr. Pääbo’s analysis of the Neanderthal FOXP2, a gene essential for language. Modern humans have two changes in FOXP2 that are not found in chimpanzees, and that presumably evolved to make speech possible. Dr. Pääbo said Neanderthals had the same two changes in their version of the FOXP2 gene. But many other genes are involved in language, so it is too early to say whether Neanderthals could speak.

UPDATE: A few days ago, I heard Wolf Enard, one of Paabo’s postdocs, speak on a fascinating project, where human version of FOXP2 was knocked in to mice (replacing the endogenous mouse version). Although the phenotypic effects were subtle, the approach itself is quite revolutionary: Putting human versions of genes into model organisms to see how the subsequent evolution of the gene changes its function. I wonder what other genes might be amenable to this approach.

PNAS roundup: Superresolution in 3D and fetal testosterone of traders

PNAS has some interesting articles that I came across today:

  1. 3D PALM (open access): Using 2-photon and photoactivatable proteins, the authors image beyond the usual sub-wavelength TIRF limits. They image over multiple microns with 50nm resolution.
  2. Neuroeconomics:  Low digit ratio (2d:4d) predicts financial success in traders. Okay, measure the length of your index and ring fingers. (Not sure if this analysis applies for the ladies; the authors only used men in the study.) Calculate the ratio (2d/4d); longer ring fingers signify greater fetal androgen exposure. The mean value is about 0.96. As the authors say,

    Digit ratios have been found to predict performance in competitive sports, such as soccer, rugby, basketball, and skiing, so 2D:4D may also predict the risk preferences and physical speed required for high-frequency trading.

    A strong correlation (r~0.5) was found between low digit ratios and profits in short-term trading. So, they take on more risk and make more money. What I want to know is how well the low 2d:4d ratio traders did over the last 6 months!

Social neuroscience fMRI: Specious correlations?

Nature is reporting on potential flaw in multiple imaging (fMRI) studies of social neuroscience. Ed Vul (a graduate student in my dept) and colleagues have a paper in press that says that many of the high correlations between brain regions and social behavior are implausible, given the inherent variability/noise in fMRI. Furthermore, based on a survey of methods from individual investigators, they created a list of papers that commit, in their view, a statistical mistake (non-independence). Naturally, the authors named in the paper aren’t happy and, according to the Nature article, several rebuttals are in the works. At the very least, to my non-expert eyes, this seems like an important discussion to have about data analysis and methodology.

Neuroscience of voting

As the first presidential debate nears, there’s a lot of excitement (and worry) regarding the election. Today, Salon had an interesting piece on voter behavior and irrational attachment to ideologies and candidates. Recounting a recent psychology paper’s punchline:

The article’s conclusion should be posted as a caveat under every political speech of those seeking office. And it should serve as the epitaph for the Bush administration: “People who lack the knowledge or wisdom to perform well are often unaware of this fact. That is, the same incompetence that leads them to make wrong choices also deprives them of the savvy necessary to recognize competence, be it their own or anyone else’s.”

Slate had a story (“Why is every neuropundit such a raging liberal?“) about how neuroscience and neuromarketing are changing political consulting (also here’s a link to a similar story in NYT last week):

According to a study of political psychology published last Thursday in Science, conservatives tend to be the jumpier lot.

The researchers called 46 political partisans into their laboratory at the University of Nebraska, affixed electrodes to their fingertips and eyelids, and measured sweat output and eye blinks in response to a series of startling stimuli. (Subjects were forced to endure images of bloody faces and maggot-infested wounds, as well as sudden blasts of white noise.) The results: Social conservatives—those who supported the death penalty, the Patriot Act, prayer in school, and the like—sweated more, and blinked more intensely, than the liberals.

The Slate and NYT articles in particular suggest something that I have long believed to be true. The Republican “story” is, from a neuroscience perspective, simply better because it tends to view the world in clear-cut terms with no middle ground and, thus, is more effective at rallying emotional processing areas of the brain (eg. limbic system). It is well-known in neuroscience that emotionally salient events that activate these limbic structures are better remembered than less charged memories. The Democratic “story” tends to be more complicated with shades of gray and therefore requires higher-level processing (eg. cortical areas involved in conflict resolution). Clearly, I’m oversimplifying things here a bit (see, I’m designing this post to appeal to your limbic system!) but I think that this hypothesis might have some legs.

Of course, if it’s true, why doesn’t everyone vote Republican if that story is the neurally more rewarding one? Or perhaps the more relevant question: Is it even possible for the Democrats to tap into the similar evolutionarily older limbic structures that seem to dominate the Republican story?

Also, although I prefer Neurodudes to stick with the science over any partisan politics, I must say I found this statistic interesting (from the Slate article):

in 2002, Daniel Klein and Andrew Western tallied the political affiliations of professors at Berkeley and Stanford and found that even in the hard sciences, Democrats outnumbered Republicans by a factor of almost 8 to 1. Among professors of neurology and neuroscience, Klein and Western counted 68 registered Democrats against just six Republicans.

Plant neuroscience

Plants Found to Show Preferences for Their Relatives – NYTimes.com

Two amazing things here:

  1. Plants missing photosynthetic enzymes of their own that migrate directionally toward “victim” plants. This behavior has an uncanny resemblance to axon guidance. Make sure to view the time-lapse video in the NYT article. Here’s an image from the PSU website:

  2. Plants capable of identifying kin and “being nice” to kin while going into a competitive mode of root growth with non-kin. Amazing.

It refreshing to see this kind of interesting behavior without any neurons involved. It makes me think (realize) that the idea of a neuron or a neural system has many components and there might not be any good reason to assume that a single cell must have all of those properties or none of them. Something like a neuron-like cell that’s not a neuron in the classical sense. Anyone know of other examples?