Snippets From Science


• Researchers at Case Western Reserve University studied the texting habits of 4,000 teenagers and found that 4 percent of them qualify as “hyper-texters.” These are teens who send at least 120 text messages a day and spend at least three hours a day on social networking sites. Hyper-texters are twice as likely to smoke, engage in sex, skip school, or abuse alcohol and drugs. Also, they were more susceptible to depression and thoughts of suicide. It’s possible that peer pressure and a tendency to impulsivity contribute to their problems, but nevertheless hyper-texting children need parents who better monitor their activities and help them make better choices. (The Week, Nov. 26, 2010)


• The way cats and dogs drink has been widely covered in the press, but here’s a summary in case you missed the “discovery.” A cat drinks by rapidly flicking the tip of its tongue to the water surface and quickly withdrawing it. A short column of water is pulled up by the tip, and the cat quickly draws the water column into its mouth and snaps it off. It’s slow work, but if the tongue flicks the water surface rapidly, the cat can consume enough to satisfy its thirst. Lions and other cats also drink this way. Dogs, on the other hand, just shove their curled tongue into the water and slop up the liquid any way they can. (Science, Nov. 12, 2010)


• Psychologists have looked at gender differences in humor and laughter. For example, when a man talks to a woman, she laughs more than he does. Men prefer slapstick and sexual humor, while women tend to make people laugh with personal or self-deprecating humor. When Carrie of the Sex and the City TV program told her friends that her boyfriend used a Post-it note to dump her, women found the comment funnier than did men. Humor varies, however, depending on whether it is in mixed company or in a same-sex group.


A psychologist at Northwestern University taped group conversations in the lab and found that women avoid self-deprecating humor in mixed company. And although men generally tended to disparage and tease more often, in mixed company, they tease less and women tease more. In mixed company both men and women appear to avoid behavior that might turn off potential mates. (Scientific American Mind, May/June 2010)


• Can a mild shock to the scalp stimulate memory? Recently neuroscientists described a technique that suggests the answer might be yes. It’s called “transcranial direct current stimulation” (tDCS) and it involves applying weak electrical stimulation to the scalp over certain areas of the brain. Stimulation to certain areas increased the ability to recall names, for example, and in Alzheimer’s patients it also seems to improve memory. It appears that this kind of subtle electrical stimulation may make underlying neurons more likely to carry or initiate an impulse. The tDCS approach is very new and no one knows where it will lead. (Brain in the News, Nov. 2010)


• Speaking of mild shocks, most people with fillings in their teeth have experienced a shock from biting into a piece of aluminum foil. Fillings are usually alloys of silver and mercury, and when they contact a piece of aluminum a tiny wet-cell “battery” is created in the mouth. The filling becomes one electrode, and the aluminum the other, both bathed in saliva which serves as the electrolyte. A sharp pain is felt as the mouth battery is short-circuited when the aluminum electrode touches the dental amalgam electrode. The current is weak, but enough to be sensed by the nerves of the teeth. The current quickly stops, and the pain ceases. (N. Davis, 2008, Alaska Science Nuggets, Univ. of Alaska Press)