We’ve known for a long time that a short afternoon nap can make a major difference to our work performance, especially if we’re involved in mental work.

Now, a new book by Harvard University sleep expert Dr Sara Mednick, Take a Nap! Change Your Life, describes the simple process of taking a nap as a “lifesaving habit”. She claims that snoozers make fewer mistakes and have boosted brainpower. One of her experiments involved one group taking a nap, another group drinking a mug of coffee (200mg of caffeine), and a control group taking a placebo.

They were then given a series of tasks, including typing and spatial skill tests. The coffee drinkers performed much worse than the placebo takers, while the nappers performed best of all. So the common assumption that coffee will keep us going through the day has probably been fed to us by the coffee industry.

Dr Mednick, a psychologist and research scientist, has accumulated a lot of evidence that a simple siesta in the afternoon is the best medicine for a happier, healthier life. People who sleep for 30 minutes at least three times a week had a 37 percent lower chance of a heart attack, according to a lead researcher from the Harvard School of Public Health.

In another study, recently published in Nature Neuroscience journal, the good doctor put 30 well-rested people through the same set of tasks four times in the course of a day, starting at 9am through to 7pm.

Performance dropped by 50 percent in those who stayed awake all day. However, the volunteers who took an afternoon nap kept up their performance throughout the day.

NASA has also made a contribution. Tests conducted by them show that astronauts who took a brief snooze doubled their alertness even if they were not tired before the nap. They also increased their work productivity by at least 13 percent.

The ideal time to nap apparently is between 1pm and 3pm which enables the most restful kind of sleep pattern for boosting performance.

I suggest you hedge your bets and take a nap now.

Do you have difficulty making decisions? Do you make decisions that you later regret or lead to worsening life situations?

The ability to make good decisions may be more important than intelligence in producing better life outcomes according to a study being done by Carnegie Mellon University and the RAND Corp.

The results of the study imply that teaching people decision-making skills could improve their quality of life.

“Intelligence doesn’t explain everything. Our results suggest that people with good decision-making skills obtain better real-life outcomes, even after controlling for cognitive ability, socio-economic status and other factors,” said Wändi Bruine de Bruin, a researcher in the Department of Social and Decision Sciences at Carnegie Mellon and the lead author of the study. “That is good news, because decision-making skills may be taught.”

Carnegie Mellon has a short version of the test online that you can take yourself to see how you score in comparison with other participants. The test takes about 15 minutes and is confidential but you do need to leave an email address for them to mail the test results back to you.

Read the article Good Decision-Makers May Be Made,
Not Born, Says Carnegie Mellon Study and take the test.

The BBC has an Internet survey on Brain Sex and if you’ve never taken it, you should go there and try it out. I remember doing this survey a year or so ago and I wasn’t surprised by the results so for me, anyway, it seemed accurate.

The data from the survey has been analyzed and research papers with key findings are being published in the current issue of the Archives of Sexual Behavior. You can read the BBC summaries of the articles at bbc.co.uk.

The survey had over 450,000 participants and 225,000 completed the survey. Some of the conclusions may be considered common knowledge, such as the finding that men rank good looks in a mate higher than women do. But some findings are intriguing. The survey results link spatial processing ability to sexual orientation.

You can take the Sex ID test here. Get a brain sex profile and find out if your brain is more male or more female. Have a ruler handy, because you will need to measure your fingers (really). It’s a revealing test that may help you understand why you think like you do.

As time passes, details in memories degrade. The memory of lunch with a friend is still with you a week later, but do you recall the color of the shirt he wore?

Ask a witness to a crime what they saw immediately following the event and they will recall more detail than they would if you waited several days or a week to ask them to recount their memories. It seems a simple concept, but often witnesses are only interviewed briefly at the crime scene. The full interview may not take place for several days. By this time, many of the important details about people and events have been forgotten. The more time that elapses between the event and being asked to fully recall the details, the less accurate the report is likely to be.

With funding from the British Academy and working with police forces in England and Scotland, Dr Lorraine Hope from the University of Portsmouth and collaborators Dr Fiona Gabbert (University of Abertay) and Professor Ronald Fisher (Florida International University) have developed the Self Administered Interview. Tests conducted using simulated crime scenes, showed that recall concerning the events was 42-44% more accurate when witnesses used the SAI following the event. A second test showed that even a week later, accuracy for details and people involved was 30% higher for those who used the SAI than for witnesses who were simply asked to “tell us all that you can remember”.

Memory decay happens very quickly in the first few days following an event and eventually slows and levels off. This means that over time, witnesses memories of events will include the basic framework of the event but be devoid of details they might have recalled if they had the opportunity to record their memories before the information is forgotten. Going over the details sooner helps strengthen and protect the memory, guarding it from the natural process of forgetting.

Scientists develop new tool to ‘freeze’ crime scene memories