Research – Brain Research
Adolescent Intermittent Alcohol Exposure: Persistence of Structural and Functional Hippocampal Abnormalities into Adulthood
http://onlinelibrary.wiley.com/doi/10.1111/acer.12725/abstract
Alcoholism: Clinical and Experimental Research. Article first published online April 27, 2015. DOI: 10.1111/acer.12725.
Alcohol abuse during adolescence may render individuals at heightened risk for subsequent alcohol abuse disorders, cognitive dysfunction, or other neurological impairments by irreversibly altering long-term brain function. To test this possibility, researchers modeled adolescent alcohol abuse (i.e., intermittent EtOH exposure during adolescence [AIE]) in rats to determine whether adolescent exposure to alcohol leads to long-term structural and functional changes that are manifested in adult neuronal circuitry. Researchers found that repeated alcohol exposure during adolescence results in enduring structural and functional abnormalities in the hippocampus. These synaptic changes in the hippocampal circuits may help to explain learning-related behavioral changes in adult animals pre-exposed to AIE.
Adolescent alcohol exposure and persistence of adolescent-typical phenotypes into adulthood: a mini-review
http://www.ncbi.nlm.nih.gov/pubmed/24813805
Neurosci Biobehav Rev. 2014 Sep; 45:1-8. doi: 10.1016/j.neubiorev.2014.04.012. Epub 2014 May 9.
Specific parts of the brain are maturing during adolescence, which leads to the question of how alcohol binging impacts development. A recent review of the science by researchers involved in this study found that when binge-levels of alcohol are given to rats during adolescence, many adolescent-typical behaviors and sensitivities fail to mature and end up persisting into adulthood. For example, adolescent rats and people show less sedation and social impairment to moderate and high doses of alcohol, but more learning impairment. When rats are exposed to binge levels of alcohol during adolescence and then tested in adulthood, they retain these adolescent-typical responses to alcohol rather than maturing into an adult response. Notably, the adult responses can be protective – people who are sensitive to alcohol sedation will fall asleep rather than continue to drink. Binge levels of alcohol in adolescence blocks certain aspects of brain and behavior from maturing, and may promote problematic alcohol use.
Alcohol and the Adolescent Brain – Human Studies
http://psycnet.apa.org/psycinfo/2006-01535-006
Alcohol Research & Health. Vol. 28(4), 2004-2005, 205-212
Many people begin to drink alcohol during adolescence and young adulthood. Alcohol consumption during this developmental period may have profound effects on brain structure and function. Heavy drinking has been shown to affect the neuropsychological performance (e.g., memory functions) of young people and may impair the growth and integrity of certain brain structures. Furthermore, alcohol consumption during adolescence may alter measures of brain functioning, such as blood flow in certain brain regions and electrical brain activities. Not all adolescents and young adults are equally sensitive to the effects of alcohol consumption, however. Moderating factors-such as family history of alcohol and other drug use disorders, gender, age at onset of drinking, drinking patterns, use of other drugs, and co-occurring psychiatric disorders-may influence the extent to which alcohol consumption interferes with an adolescents normal brain development and functioning.
Alcohols Effects on the Adolescent Brain-What Can Be Learned From Animal Models
Alcohol Research & Health. 2004; Vol. 28, No. 4
Because of legal and ethical constraints on alcohol research in human adolescents, many studies of alcohols effects on the developing brain have been conducted in animal models, primarily rats and mice. The adolescent brain may be uniquely sensitive to alcohols effects because major changes in brain structure and function occur during this developmental period. For example, adolescent animals are more sensitive than adults to the effects on memory and learning that result from alcohols actions on the hippocampus. Conversely, adolescent animals appear to be less sensitive than adults to alcohol-related motor impairment, alcohol-induced sedation, and the development of seizures during withdrawal. Alcohol exposure during adolescence can have long-lasting effects and may interfere with normal brain functioning during adulthood.
Adolescent Alcohol Dependence May Damage Brain Function
http://www.nih.gov/news/pr/feb2000/niaaa-14.htm
A study in the February 2000 Alcoholism: Clinical and Experimental Research (Volume 24, Number 2) presents the first concrete evidence that protracted, heavy alcohol use can impair brain function in adolescents. It is unclear at present whether the damage is reversible.