Researchers of the University of Wisconsin-Madison studied 38 5- to 7-year-old rhesus monkeys born to mothers who either drank a moderate dose of alcohol every day during their pregnancies, were exposed to a mild 10-minute stressor during their pregnancies, drank a moderate amount of alcohol and were exposed to the stressor during their pregnancies, or were undisturbed while they were pregnant. A moderate dose of alcohol for the monkeys was defined as the equivalent of two drinks a day for a human.
Without knowing which situation the mother monkeys had experienced, the researchers rated the monkeys’ offspring according to how they responded to repeated touch with a feather, a cotton ball, and a stiff brush. They found that monkeys whose mothers had not been stressed or consumed alcohol got used to touch over time, while monkeys whose mothers had been stressed grew more disturbed by touch over time. Monkeys who had been exposed to alcohol prenatally were disturbed by touch more than monkeys who had not been exposed to alcohol prenatally.
Using a brain neuro-imaging technique known as positron emission tomography, or PET, the researchers found that the monkeys’ sensitivities to touch were related to changes in a brain chemical called dopamine in one area of the brain, the striatum. Regulating dopamine plays a crucial role in mental and physical health. Particularly important for learning, dopamine plays a major role in addictions.
“Our results with monkeys have important implications for preventing childhood disorders,” according to Mary L Schneider, the study’s lead author.
MEDICA.de; Source: Society for Research in Child Development