A little late with this one as I’ve been busy with my gaming blog. Three articles this month and all them are about human nature. The first one examines whether or not there is a placebo effect in the consumption of coffee, the second one examines if the habit of overspending has a genetic component and the last one tells about the surprising fact that the most successful male athletes also tend to be the most good looking ones.

Like many other people, I have the habit of drinking a cup of coffee every morning, but unlike some people, I’m not conscious of whether this actually has any effect on my concentration. Plenty of people seem to think it’s essential for them to function properly in the office so scientists are understandably curious about whether or not the effect is real. This post on Neuroskeptic links to and summarizes a new paper about a study that tried to determine whether or not the claimed benefits of caffeine are attributable to the placebo effect.

The study involved sixty volunteers who were all told that they were being given real coffee. However, only some of them were given extra-strength concentrated coffee and the rest were given placebo decaffeinated coffee. Half of the volunteers were also told that the coffee would impair their concentration while the other half were told that it would boost their performance. Thirty minutes after drinking, all the volunteers were assigned tasks designed to measure their concentration and speed.

The results were that caffeine really did make a difference as those who had been given real coffee performed measurably better at the tasks. The surprise however was that telling the volunteers who were not given real coffee what to expect led to opposite results. Those who were told that the fake coffee would impair their performance actually did better, presumably because they worked extra hard to overcome what they were told would be a handicap. Those who were told that it would help them did worse.

The post ends with the observation that while the objective results could clearly differentiate between those who had been given real coffee and those who had not, the volunteers themselves could not tell the difference. They rated their own performance and alertness levels similarly regardless of whether they were given real coffee or not. This suggests that when someone claims that coffee helps them concentrate, it may well be perfectly true, but they shouldn’t be able to objectively tell the difference.

The next article which comes from SmartMoney takes extra pains to explain that there’s no such thing as a “debt” gene and that it is scientifically impossible for such a thing to exist, but it does lay out how genetics may play a role in determining the development of a person’s financial habits. The article cites research by Jan-Emmanuel De Neve, of the London School of Economics, and James Fowler, of the University of California, San Diego who found a correlation between carriers of “low-efficiency” alleles of the MAOA gene and incidences of credit card debt.

As the article explains, the MAOA gene is responsible for the encoding of an enzyme that degrades neurotransmitters in parts of the brain that regulate impulsiveness. Some versions of the gene are less efficient at producing this enzyme than others and this has previously been linked to character traits that include a lack of conscientiousness and a tendency to impulsivity. The researchers looked through a genetic database of young people in the U.S. to find people with the low efficiency version of the gene and predicted that they would be more likely to report carrying credit card debt.

Not only was the prediction borne out, but individuals who carried low-efficiency versions of the gene in both alleles were more likely to report credit card debt than individuals who only had it in one allele. Once again, how genetics affect actual human behavior is a complex matter that involves many different factors, so it would unwise to lay blame or give credit based on genetics alone, but given the wealth of information now available, it would be equally unwise to dismiss such findings altogether, especially as they have very real consequences on society and individual lives.

Finally, the last article in New Scientist shows how athletic performance is correlated with good looks based both on a study by Justin Park at the University of Bristol, UK and an informal survey by New Scientist itself using Twitter. The academic study was done by asking women to rate the attractiveness of elite American football players while the survey by New Scientist was done online based on photos of professional male tennis players. Both found that women rated the best performing sportsmen as being the most physically attractive.

The correlation was modest, but was still present even when the data was controlled to compare between sportsmen in the same positions, for example, quarterbacks in American football teams. The study asked Dutch women, who presumably would not be familiar with the faces of American football players, to rate the attractiveness of quarterbacks. The researchers similarly ranked the quarterbacks according to their performance on the field using passer ratings that are an amalgamation of several sports statistics and similarly found correlations between the two measurements.

Of course, neither study claims to imply that either factor causes the other, merely that the genetic components that help determine whether a male is a good sportsman or not also helps determine his level of physical attractiveness in the eyes of females. Nevertheless, it’s a good real-world example of how the development of our species in our evolutionary past, during which time physical attributes were important for survival, continues to influence our perceptions in the present.