Teen-agers with a few beers under their belts may feel as if they'll be young forever, but the results of a study conducted at the University of Florida suggest that if they continue to consume alcohol, they will actually age more rapidly.
The study, conducted by Dr. Gerhard Freund of the university's college of medicine, studied the long-term effects of alcohol consumption on laboratory mice. One group of mice received an amount of alcohol equivalant to that consumed by heavy drinkers. The mice in the other group were teetotalers.
After a period of drying out, both groups were tested at a variety of tasks. The mice that received the alcohol-heavy diet, the researchers found, were severely impaired in the areas of learning and memory. Such changes are also characteristic of aging. The alcohol-induced changes seem to be irreversible, Dr. Freund says.
Autism, characterized by withdrawal, language disorders, and failure to establish normal social contact with the world, is one of the most common childhood psychiatric disorders, and it remains one of the most mysterious as well.
But after years of research, scientists have recently uncovered evidence that suggests that the disorder may be biochemical in origin.
Specifically, the evidence implicates serotonin, a neurotransmitter, or chemical messenger, that travels between nerve cells in the brain. Over the past 10 years, studies have found that about 40 percent of autistic children have abnormally high levels of serotonin in their blood.
The strongest, but still preliminary, evidence was reported this summer, when researchers at the University of California at Los Angeles found that three autistic children who were treated with a drug that reduces the levels of serotonin in the brains of animals showed a reduction in behavioral symptoms as well as a drop in blood-serotonin levels.
Roland Ciaranello, a professor of psychiatry at Stanford University, plans to follow these clues, continuing and expanding a study of autistic children in the Bay Area. His research group will compare patterns of behavior with the levels of serotonin in three groups: autistic children, children who are mentally retarded but not autistic, and normal children. In a separate study, they will examine the possible links between levels of endorphins, the brain chemicals that seem to be linked to pain, and autism.
Six months after a report from the National Academy of Sciences called marijuana's health effects a topic of "grave national concern," the Surgeon General has issued a warning on the use of the drug.
Of particular concern, the warning says, are the long-term, developmental effects on children and adolescents. Young people who use the drug frequently are prone to the "amotivational syndrome," characterized by a pattern of energy loss, diminished academic performance, damaged family relationships, and other problems.