Alterations in brain chemistry may lead to addiction in some people who dabble in illicit drugs, while sparing others. Researchers hope the findings will help them learn why some people are particularly vulnerable to abusing drugs. In the study, found that study subjects who found the effects of a mild stimulant drug to be pleasurable had lower levels of the dopamine D2 receptor in their brains, while those who expressed distaste for the drug's effects had measurably higher levels of the receptor. Receptors are structures that bind specific substances to a cell, either on the cell's surface or in its interior. This is the first evidence in humans showing an association between D2 receptor levels in the brain and the reinforcing responses to stimulants. People with fewer dopamine receptors may take drugs to activate... pleasure circuits in the brain which may be one of the factors that predisposes a person to drug abuse.

SOURCE: American Journal of Psychiatry September 1999.

FOREIGN ADOPTEES: GROWTH, DEVELOPMENTAL DELAYS CORRELATE WITH ORPHANAGE TIME

The medical records that accompany children adopted from foreign countries may be inaccurate, and growth and development delays in foreign adoptees are often related to time spent in an orphanage. Significant growth and developmental delays were common in the children, while "...neurologic diagnoses cited in pre-adoptive medical reports from Eastern Europe and the former Soviet Union were not confirmed. Time spent in an orphanage directly correlated with the degree of growth lag in the children, with 1 month of growth delay tagged to every 5 months spent in an orphanage. Only one of the 56 children in this sample was diagnosed with fetal alcohol syndrome. But this may be an underestimation of the true prevalence of the syndrome in these children, since "...problems attributable to fetal alcohol syndrome may become more apparent as children get older." The researchers recommend that physicians view foreign adoptees, at least on a short-term basis, as "special needs" children and provide them with "...a period of intensive rehabilitation."

SOURCE: JAMA 1997;278:922-924.

ALCOHOL'S EFFECTS ON FETAL BRAIN REVEALED

For the first time, researchers have discovered how drinking alcohol during pregnancy damages the brain of a fetus. In the United States, about 1 out of every 1,000 children is born with fetal alcohol syndrome, which can cause a range of problems, including learning and memory problems, hyperactivity, stunted growth, and an abnormally small head. According to a report in the February 11th issue of the journal Science, getting drunk just one time during the final three months of pregnancy may be enough to cause brain damage in a fetus. "This is the first time we've had an understanding of the mechanism by which alcohol can damage the fetal brain. It's a mechanism that involves interfering in the basic transmitter systems in the brain, which literally drives the nerve cells to commit suicide." The brain is thought to be most sensitive to the effects of alcohol during a period called synaptogenesis, when the brain develops rapidly. In people it begins in the third trimester of pregnancy and continues into early childhood. The investigators determined that alcohol affects two brain chemicals, glutamate and GABA, which help different parts of the brain communicate with each other. Researchers noted that just one episode of drunkenness during the third trimester, when brain cells are developing rapidly, would be enough to damage the brain of a fetus. Researchers plan to continue to study the results of alcohol exposure on rats as they mature, with the goal of discovering the link between damage to certain parts of the brain and problems in the adult animal.

SOURCE: Science 2000;287:947-948, 1056-1060.

PRENATAL ALCOHOL EXPOSURE LINKED TO ATTENTION-DEFICIT DISORDER

Attention-deficit/hyperactivity disorder may be the result of damage to part of an unborn child's brain that is caused by a mother's alcohol intake during pregnancy. The part of the brain damaged before birth involves a complex communication system between nerve cells. Researchers found that the electrical activity of specific neurons (in the brain) was reduced in the offspring of pregnant rats treated with alcohol. The neurons normally generate a certain amount of spontaneous electrical activity that is responsible for attention. Researchers think that attention/hyperactivity problems may be caused by the reduced activity in those neurons," Alcohol exposure impairs the development of brain dopamine neurons which ultimately results in a decrease in the quantity of dopamine released in areas of the brain that control attention and the ability to focus. Clinicians want to reexamine the notion that ADHD may be outgrown since the reduced dopamine function is a persistent phenomenon during adulthood.

SOURCE: Alcoholism: Clinical & Experimental Research 1999;23.

EFFECTS OF PRENATAL COCAINE SEEN IN 2-YEAR-OLDS

Toddlers who were exposed prenatally to cocaine had signs of impaired motor skills compared with children of the same age who were not exposed to cocaine. The findings suggest that children exposed to cocaine and to alcohol in utero "may encounter developmental challenges that impede later achievement." Researchers found that the youngsters who had been exposed to cocaine before birth scored lower in tests of their fine motor skills, primarily hand use and eye-hand coordination. There was also evidence that there is an increased rate of abnormal fine motor development in the cocaine exposed group. It is also possible that some young children may be exposed to cocaine smoke in their homes and that postnatal exposure may affect their motor abilities.

SOURCE: Pediatrics 1999;103:86-92.

FDA APPROVES SIMPLE ALCOHOL ABUSE TEST

The US Food and Drug Administration has approved a new test by Axis-Shield that will make it easier to find out if someone is abusing alcohol. he product, known as %CDT, will identify symptoms of alcohol abuse more quickly than other products, the company states. It measures the blood level of carbohydrate-deficient transferrin, which rises after continuous consumption of alcohol. The market potential for %CDT is thought to be significant in the US, since it is estimated that about 10% of the population has alcohol-related problems, Axis-Shield said. Currently, there are many alcohol and drug testing kits for home or business use.

For more information about these products got to www.proveitinc.com or www.homedrug-test.com

ALCOHOLICS MAY SELF-MEDICATE WITH SWEETS

Drinking among some alcoholics may be a way of increasing the body's levels of the brain chemical serotonin, according to recent study findings, and low levels of this chemical may also cause them to crave sweets. Researchers explain that "carbohydrate craving may be an important clue to developing more diversified treatments for alcohol-dependent subjects." The team reports that diet has a significantly different effect on alcoholics who have high cravings for carbohydrates compared with those who report lower levels of cravings. Alcohol and carbohydrates have both been shown to increase levels of serotonin in the body, the researchers explain. Low levels of this chemical can lead to depression, anxiety, aggression, and sleep problems. The authors point out that sweets seem to have a paradoxical effect on patients with high levels of craving: they appear to provide a brief improvement in mood followed by a longer period of mood worsening. Similar findings have been reported in patients with depression and bulimia.

Alcoholics with strong cravings for carbohydrates may form a distinct subgroup of patients with this disease. This type of alcoholic may drink to increase their serotonin levels, and may increase their intake of carbohydrates if not drinking, to achieve the same effect, the researchers suggest. This response may reinforce alcohol and/or food intake and perpetuate substance abuse," they add. High carbohydrate craving alcohol-dependent subjects are potentially at greater risk for relapse than low carbohydrate craving alcohol-dependent subjects.

SOURCE: Alcoholism: Clinical & Experimental Research 2000;24:635-643.

BRAIN DIFFERENCE SPOTTED IN ANTISOCIAL PERSONALITY DISORDER

Patients with antisocial personality disorder (APD) are more likely than other individuals to lie, be impulsive and irresponsible, lack remorse, and commit violence. Study findings suggest that these patients also have less gray matter than normal in the prefrontal cortex, an area at the front of the brain that plays a role in controlling emotions and behavior. These findings provide the first evidence for a structural brain deficit in APD. The prefrontal cortex "is the part of the brain that acts to regulate and control behavior. The gray matter are the nerve cells, the thinking part of the brain, and the white matter are the connection wires which link the cells together, which allow them to communicate. APD patients also have reduced autonomic activity -- that is, they sweat less and do not experience an increase in their heart rate when under stress -- unlike normal individuals.Prefrontal dysfunction is just one of many factors that predisposes to violence .It does not explain all factors of antisocial personality. Other factors include social factors such as drug and alcohol abuse, high levels of testosterone, and birth complications.

SOURCE: Archives of General Psychiatry 2000;57:119-127, 128-129.

BRAIN REORGANIZES IN THE DEAF, BLIND - COULD THERE BE HOPE FOR CHILDREN WITH FAS?

Areas of the brain normally used to process sound or sights appear to be reorganized and reassigned to other tasks in blind and deaf individuals, two new studies suggest. In deaf individuals, the temporal lobe of the brain, which is typically used to process sounds, is active during visual processing tasks, deaf people are able to rewire that part of the brain that is usually used for vision. Researchers used functional magnetic resonance imaging (MRI) to monitor deaf and blind individuals and compared the results to non-affected cleints. In both groups, the brain essentially re-wired itself to allow other areas of the brain to take over tasks. Researchers will continue to see if people with brain injuries can adapt and can learn to do tasks the damaged area can no longer accomplish.

SOURCE: Reported by Dr. Dean K. Shibata of the University of Rochester, New York at the recent Radiological Society of North America meeting (1998)

TEST PREDICTS ALCOHOL-RELATED BIRTH DEFECTS

A blood test that identifies women who drink heavily while pregnant could help physicians identify babies at risk for fetal alcohol syndrome, the most common preventable cause of mental retardation in North America. A combination of four chemical indicators of alcohol, called biomarkers, has been found in the blood of women who drink heavily while pregnant. The test is more effective in assessing the alcohol exposure of unborn children than the current method of asking women to quantify their drinking, and could lead to better prevention of alcohol-induced fetal damage. Mothers who tested positive for two or more of the alcohol biomarkers had children with significantly lower birth weights, shorter lengths, and smaller head sizes than infants whose mothers tested negative for alcohol consumption. The test was not completely accurate in predicting all of the infants born with alcohol related birth defects. If used appropriately and in combination with other self-reporting measures in a clinical setting, the use of these biomarkers could enhance the clinician's ability to identify women at risk.

SOURCE: Journal of Pediatrics 1998;133:316-317, 346-352.

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