We could flip a coin to decide which ref to believe. But this merely gives us a decision performance which is the average of the decision performance of each individual ref. So this is no good.

We could figure out which ref is better and then always believe that ref whenever the two refs disagree. But in that case the second ref isn’t contributing anything, so we may as well just have one ref.

However, if the two refs have some estimate of their uncertainty, then we can do better. If d1 represents where ref one thinks the ball landed, and d2 represents what ref 2 thinks, and if o1 and o2 represent each ref’s report of the standard deviation of their own estimate, then the optimal way to combine both refs’ guesses into a final guess is

(d1/o1^2 + d2/o2^2) / (1/o1^2 + 1/o2^2)

which gives better performance than either ref, individually. Since we only care about whether the ball went over the line, if the line is at d=0, then this rule simplifies to testing if

d1/(o1^2) + d2/(o2^2) > 0

Is that what humans do? No. Apparently, when put together in pairs and given the chance to communicate, humans communicate both their guesses and their uncertainties, and effectively use the following formula to make a cooperative guess:

d1/o1 + d2/o2 > 0

This rule provides better performance than individual decision-making provided the difference between o1 and o2 (the uncertainties of the refs) is less than 40%. If it is more than that, this rule is worse than just having the more reliable ref make all the decisions.

Why do humans use d1/o1 + d2/o2 instead of the optimal formula, d1/o1^2 + d2/o2^2? One hypothesis is that the former is unit-free, whereas the latter requires both refs to communicate with each other in terms of (matching) spatial units.

summary:

Marc O. Ernst. Decisions Made Better (27 August 2010)
Science 329 (5995), 1022.

article:

Bahador Bahrami, Karsten Olsen, Peter E. Latham, Andreas Roepstorff, Geraint Rees, and Chris D. Frith. Optimally Interacting Minds (27 August 2010)
Science 329 (5995), 1081.

“Dr. Tononi sees serious problems in these models. When people lose consciousness from epileptic seizures, for instance, their brain waves become more synchronized. If synchronization were the key to consciousness, you would expect the seizures to make people hyperconscious instead of unconscious, he said. “

http://www.nytimes.com/2010/09/21/science/21consciousness.html?_r=1

Jouny et al (2010) http://www.ncbi.nlm.nih.gov/pubmed/19910249 surely should have suggested that this is premature closure, with an INCREASE in signal complexity – that is, decline in synchrony – associated with seizure

Our study of ECOG data (electrodes directly attached to the cortex, not on the scalp) confirms this. Sleep signal is least complex/disordered under PCA, first component explains 97%, awake is next, with 93% explained by the first component, while seizure has just 63% explained by first component.

Sean O Nuallain PhD

Basically, all of the following improve recall:

• spacing out study time over a longer period of time
• alternating between multiple topics in one study session
• studying the same thing in different locations
• taking a test

In summary, recalling and using knowledge in a variety of contexts helps you remember it.

In her book Delusions of Gender (which I have not read though am intrigued to do so), cognitive neuroscientist Cordelia Fine places several modern studies of early differences in brain anatomy/function into a long line of sexist explanations for supposed differences in male and female behaviors.

The basic argument is that there has been no convincing connection made between any measured structural differences (which she argues might not exist) to behavioral differences. Just another case of correlation (maybe) and not causation.

Here’s a description of study that you might already be familiar with and Fine’s take on it:

Dr. Baron-Cohen’s lab conducted research on infants who averaged a day and a half old, before any unconscious parental gender priming. Jennifer Connellan, one of Dr. Baron-Cohen’s graduate students, who conducted the study, showed mobiles and then her own face to the infants. The results showed that among the newborns the boys tended to look longer at mobiles, the girls at faces.

Dr. Fine dismantles the study, citing, among other design flaws, the fact that Ms. Connellan knew the sex of some of the babies. Because it was her face they were looking at and she was holding up the mobile, Dr. Fine says, she may have “inadvertently moved the mobile more when she held it up for boys, or looked more directly, or with wider eyes, for the girls.”

Although I am unsure about the scientific merits, it is refreshing to see a new viewpoint in this debate. It provides some food for thought on this interesting topic:

Summarizing the research, she writes, “Nonexistent sex differences in language lateralization, mediated by nonexistent sex differences in corpus callosum structure, are widely believed to explain nonexistent sex differences in language skills.”

What all this adds up to, she says, is neurosexism. It’s all in the brain.

After the jump some more from Junger and a nice talk from Robert Sapolsky about similar behaviors in chimps.

Another example from soldiers in Afghanistan is the “blood-in, blood-out” ritual for increasing group cohesiveness and testing individual sacrifice for the group, as Junger describes near the end of this Daily Show clip:

All of these explanations and rituals reminded me of Robert Sapolsky’s and Frans de Waal’s observations of similar behavior that is reported in baboon/chimp groups.

In the clip below (from Stanford’s Class Day 2009 speech), Sapolsky describes several “uniquely human” behaviors (or at least ones that had been thought to be “uniquely human”) which really are shared by these close relatives. Starting around 12:20 (the clip below will auto-start there), he talks about aggression and the organized group killing done by “border patrols”. The entire talk by Sapolsky (~35 mins) is worth watching too!

Paul Bloom talks about research on the morality of small children, and ways in which their morality is similar to and different from adults. Concise descriptions of supporting experiments is given throughout.

Basically, babies prefer nice people over mean people, but prefer people who punish mean people over people who reward mean people. But babies are not impartial; for example, they give favorable treatment to other babies who are wearing the same tee-shirt as themselves.

Also has some content about the cognition of babies in general. Experiments show that, at various young ages, “..babies think of objects largely as adults do, as connected masses that move as units, that are solid and subject to gravity and that move in continuous paths through space and time,” and “…expect people to move rationally in accordance with their beliefs and desires…”, and “…know that other people can have false beliefs”.

The authors, Cutting, DeLong, and Nothelfer, speculate that the pink noise bit is being driven by some process that is related to attention, since there are some other results (which they cite) showing the relevance of pink noise to attention.

However, IMDB ratings were not positively correlated with the pink-noise-ness of the movie (partial correlation with release date factored out).

Incidentally, this guy did his PhD thesis on cognitive science explanations for film editing techniques.

James E. Cutting, Jordan E. DeLong, and Christine E. Nothelfer. Attention and the Evolution of Hollywood Film. Psychological Science February 2010 , first published on February 5, 2010 doi:10.1177/0956797610361679.

Watch it online at the TED website.

http://www.nytimes.com/2009/08/11/science/11naming.html

Cecil Brown, an anthropologist at Northern Illinois University who has studied folk taxonomies in 188 languages, has found that people recognize the same basic categories repeatedly, including fish, birds, snakes, mammals, “wugs” (meaning worms and insects, or what we might call creepy-crawlies), trees, vines, herbs and bushes.

Dr. Brown’s finding would be considerably less interesting if these categories were clear-cut depictions of reality that must inevitably be recognized. But tree and bush are hardly that, since there is no way to define a tree versus a bush. The two categories grade insensibly into one another. Wugs, likewise, are neither an evolutionarily nor ecologically nor otherwise cohesive group. Still, people repeatedly recognize and name these oddities.

Likewise, people consistently use two-word epithets to designate specific organisms within a larger group of organisms, despite there being an infinitude of potentially more logical methods. It is so familiar that it is hard to notice. In English, among the oaks, we distinguish the pin oak, among bears, grizzly bears. When Mayan Indians, familiar with the wild piglike creature known as peccaries, encountered Spaniards’ pigs, they dubbed them “village peccaries.” We use two-part names for ourselves as well: Sally Smith or Li Wen. Even scientists are bound by this practice, insisting on Latin binomials for species.

There appears to be such profound unconscious agreement that people will even concur on which exact words make the best names for particular organisms. Brent Berlin, an ethnobiologist at the University of Georgia, discovered this when he read 50 pairs of names, each consisting of one bird and one fish name, to a group of 100 undergraduates, and asked them to identify which was which. The names had been randomly chosen from the language of Peru’s Huambisa people, to which the students had had no previous exposure. With such a large sample size — there were 5,000 choices being made — the students should have scored 50 percent or very close to it if they were blindly guessing. Instead, they identified the bird and fish names correctly 58 percent of the time, significantly more often than expected for random guessing. Somehow they were often able to intuit the names’ birdiness or fishiness.

….

Doctors found that upon recovering from swelling of the brain caused by herpes, J.B.R. could no longer recognize living things.

He could still recognize nonliving objects, like a flashlight, a compass, a kettle or a canoe. But the young man was unable to recognize a kangaroo, a mushroom or a buttercup. He could not say what a parrot or even the unmistakable ostrich was. And J.B.R. is far from alone; doctors around the world have found patients with the same difficulty. Most recently, scientists studying these patients’ brains have reported repeatedly finding damage — a deadening of activity or actual lesions — in a region of the temporal lobe, leading some researchers to hypothesize that there might be a specific part of the brain that is devoted to the doing of taxonomy. As curious as they are, these patients and their woes would be of little relevance to our own lives, if they had merely lost some dispensable librarianlike ability to classify living things. As it turns out, their situation is much worse. These are people completely at sea. Without the power to order and name life, a person simply does not know how to live in the world, how to understand it. How to tell the carrot from the cat — which to grate and which to pet?