Here is some calming news. Researchers have found a way to simulate the brain's “all-clear” signal that turns off fear, shows a study published in Nature. Rats that had been conditioned to freeze with fear when a tone was followed by an electric shock no longer froze when the tone was not followed by the shock. Researchers demonstrated that they could mimic the brain's extinguishing of the fear response by stimulating the infralimbic area of the prefrontal cortex. They speculate that stimulating parts of the prefrontal cortex in patients with anxiety disorder might help them control their fears.

Is the drone of the highway putting you to sleep? If so, you aren't alone. According to a poll conducted by the National Sleep Foundation, more than one half of Americans say they feel sleepy when they are on the road, and 17 percent report that they have fallen asleep while driving within the past year. The poll shows that men and all adults between 18 and 29 years of age are most likely to be drowsy drivers, while adults 65 years and older are least likely to be sleepy when behind the wheel. Stopping to rest may stave off sleepiness temporarily, but the only true remedy is to get enough sleep before hitting the road.

The way patients cope with a diagnosis of cancer has been thought to affect their chances of survival. But in a systematic review of 37 prospective observational studies reported in BMJ, researchers found little evidence to support this popular belief. Only a few small studies showed that two of the most well-known psychologic coping styles—a fighting spirit and helplessness/hopelessness—influenced outcomes (for the better or for the worse) in persons with cancer. Evidence also was lacking to show that attitudes of acceptance, fatalism, or denial affected outcomes. In light of the findings, researchers say that persons with cancer should not feel pressured to change their attitudes to improve survival or reduce the risk of recurrence.

Premature neonates no longer receive the amniotic fluid they swallowed constantly in the womb, and they may be designated to have no oral intake for the first days of life. This can result in blunted villous development and feeding intolerances, according to a study published in the Annals of Pharmacotherapy. Researchers developed an amniotic fluid–like solution to be given enterally. All but three of 30 patients given the solution in a multicentered, dose-escalation trial showed no signs of intolerance. Researchers believe that simulated amniotic fluid, which contains enteric growth factors, promotes villous development.

Scientists have given new meaning to the “B.O.” in Botox. Injections of botulinum toxin A—best known for erasing frown lines—can make sweat smell sweeter, shows a study published in the Archives of Dermatology. Sixteen participants who received Botox injections in one armpit and a salt solution in the other emitted a less intense, more pleasant odor in the Botox-treated side, according to a T-shirt sniff test. How does it work? Injecting Botox into underarms may block the nerves leading to sweat glands or interfere with skin microbes.

The U.S. Food and Drug Administration has approved a rapid AIDS test that health officials hope will substantially increase the number of people seeking testing and the number who return for test results. Until now, the fastest test took about 90 minutes; the new test provides a result in about 20 minutes, according to a news item in the Washington Post. Because the test detects only HIV antibodies, there is a period of several weeks to three months in which a person can be infected with the virus and still test negative for it. When the antibodies are present, however, the test detects them 99.6 percent of the time.

Pediatricians and child psychiatrists are increasingly turning to pharmacology as the treatment of choice for psychiatric disorders in children. From 1987 to 1996, the number of children and adolescents who took a wide variety of psychiatric drugs more than doubled, shows a population-based analysis published in the Archives of Pediatrics and Adolescent Medicine and cited in The New York Times. Of the 900,000 children included in the analysis, 6.2 percent took at least one psychiatric drug in 1996, compared with 2.5 percent in 1987. Stimulants and antidepressants were the most commonly prescribed drugs.

For the latest advances in science, press “print.” According to New Scientist, researchers at the Medical University of South Carolina and Clemson University are using desktop printers filled with a cell solution instead of ink to create tubes of living tissue. Although modified printers are already being used to print arrays of DNA, proteins, or cells, this is the first time tissue engineers have successfully printed three-dimensional structures. The development may lead the way toward printing complex tissues and even organs.

Are you eating fish for health reasons? You may want to consider going wild. According to an article in BusinessWeek, wild fish may be healthier than farm-raised fish because they are leaner, have a higher percentage of healthy omega-3 fatty acids, and are not exposed to antibiotics. Choosing wild fish over farm-raised fish has its drawbacks, however. Wild fish can be more expensive than farm-raised fish, and some kinds are difficult to find year-round. Species such as shark and swordfish pose a risk of mercury contamination, so it's wise to exercise caution with them.

A study of twins appears to bolster the theory that early marijuana use can lead to use of harder drugs. Published in JAMA, the cross-sectional survey found 311 sets of same-sex twins, including 136 sets of identical twins, in which just one twin had smoked marijuana before age 17. Early marijuana smokers were found to be up to five times more likely to move up to harder drugs, and to become dependent on alcohol and drugs, than their twins. Further research is needed to explore the effects of the peer and social contexts within which marijuana is obtained and used.

Too little sleep may raise the risk of developing coronary heart disease (CHD). According to a study of 71,617 female nurses aged 45 to 65 years, published in the Archives of Internal Medicine, women who averaged five hours or less of sleep a night were 39 percent more likely to develop CHD than women who slept eight hours. Women who slept six hours a night had an 18 percent higher risk of developing blocked arteries. Because of these findings, researchers say adequate sleep should be considered an important part of a healthy lifestyle.

Remember that resolution you made to change your diet? If you haven't resolved your eating problems, you may just need to talk about them. According to new recommendations from the U.S. Preventive Services Task Force, intensive counseling in healthier eating for people at risk for heart disease is effective enough to become a part of standard care. The program goes beyond simple counseling to include an initial dietary assessment, use of a food diary, involvement of family members in providing support, group counseling, individually tailored goals, and strong follow-up. Cited in The New York Times, the panel's chairman said that a plan with many specific steps is more likely to be successful.