London: Foetuses exposed to heavy binge drinking by their mums while still in the womb require significantly more trials to habituate and also exhibit a greater variability in test performance, a new study has revealed. While it has become clear that drinking during pregnancy can damage the fetal central nervous system, these outcomes can also be influenced by factors such as timing, type, amount, and duration of alcohol exposure.
Furthermore, most studies of fetal neurobehavioral effects have been conducted during the postnatal period. This study is the first of its kind, examining alcohol's effects on fetal brain function - information processing and stability of performance - at the time of exposure to alcohol.
"When examined after birth, individuals who have been prenatally exposed to alcohol exhibit a wide range of behaviours that are indicative of central nervous system dysfunction," Peter G. Hepper, a professor of psychology at Queen's University of Belfast, as well as corresponding author for the study, said.
"These can include poorer abilities to learn, deficits in attention, poorer abilities to plan and organize, and an inability to learn about the consequences of actions.
"As a consequence, they may demonstrate behavioural difficulties and social problems which might lead to problems at school, and often 'trouble with the law'," he said.
Leo Leader, a senior lecturer in the School of Women's and Children's Health at the University of New South Wales said that this study used a process of habituation, which is the ability of an organism to stop responding to repeated stimulation.
"This reflects the ability of the central nervous system to learn to recognize a particular stimulus," he said. "It is widely accepted that habituation represents a basic form of learning. "Previous research has shown that the normal human fetus habituates, but habituation rates are altered if the fetus is exposed to reduced oxygen levels, maternal smoking, maternal sedatives, and impaired fetal growth," he added. The findings will be published in the journal Alcoholism: Clinical and Experimental Research.