"The effects of the alcohol on the mother's behavior are very subtle," he explained, "but enough to make the experience aversive for the rat pup. There are some aspects of maternal behavior that are poorer in mother rats that have had alcohol. For example, retrieval behavior -- when a mother retrieves a baby rat that has wandered away from the nest -- is inhibited by alcohol. Another effect of alcohol on the mother is a decrease in body temperature; it may be a drop of only one and a half degrees centigrade, but the pups may detect the difference in warmth."
"The animal model and the human literature are telling a similar story," said Julie A. Mennella, biopsychologist at Monell Chemical Senses Center. "Memories are not only formed as a result of early sensory experiences with alcohol in the context of the mother, but they're also retained for a considerable time span. This study is telling us that the presence of alcohol odor is capable of supporting some type of conditioning, such as aversion, when it's paired with a new stimulus, such as sandpaper."
Mennella said that Spear and Molina's study is part of a growing body of research that speaks to the relevance of early learning. "Other research has shown that elementary-school-aged children of alcoholics were more likely to report more negative experiences about alcohol than children from non-alcoholic homes," she said. "Some of the early learning about alcohol appears to be based on sensory experience and the context in which alcohol is experienced." Indeed, Mennella believes this study speaks to the power of odor associations.
"Odors are often thought to provide us with the best memory cues," she said. "Some of our oldest and most emotionally laden memories are associated with odors. Odors take us to our past." Mennella described a study conducted at her institution in which children were asked to comp
Contact: Norman E. Spear, Ph.D.
Alcoholism: Clinical & Experimental Research