Neurobiological relationships between aging and alcohol abuse.

Both biological aging and chronic exposure to alcohol may cause impaired learning and memory in man and animals. The chains of processes beginning with molecular changes that in turn alter electrophysiology and morphology and finally culminate in changes of behavior (individual and social) are largely unknown. While these chains originating with molecular events leading to the same behavioral end result may be totally different, they may also overlap at any one of these levels of biological organization, accentuate, attenuate each other, to branch again and to develop parallel to each other. There is currently some evidence from observations in humans and animals that both aging and chronic alcohol toxicity induce the following changes: brain atrophy measured in vivo by computerized tomography, histological loss of the dendritic tree of neurons in various brain regions including hippocampus and cerebellum, and a variety of chemical changes of brain synaptic function, such as loss of benzodiazepine receptors.