From: unk...@googlegroups.com   
      
   Heavy drinking in adolescence associated with lasting brain changes, animal   
   study suggests   
      
   Date:   
   October 28, 2014   
   Source:   
   Society for Neuroscience   
      
   "Our study provides novel data demonstrating that alcohol drinking early in   
   adolescence causes lasting myelin deficits in the prefrontal cortex,"   
   Richardson said. "These findings suggest that alcohol may negatively affect   
   brain development in humans and    
   have long-term consequences on areas of the brain that are important for   
   controlling impulses and making decisions."   
   Credit: © stokkete / Fotolia   
      
   Heavy drinking during adolescence may lead to structural changes in the brain   
   and memory deficits that persist into adulthood, according to an animal study   
   published October 29 in The Journal of Neuroscience. The study found that,   
   even as adults, rats    
   given daily access to alcohol during adolescence had reduced levels of myelin   
   -- the fatty coating on nerve fibers that accelerates the transmission of   
   electrical signals between neurons. These changes were observed in a brain   
   region important in    
   reasoning and decision-making. Animals that were the heaviest drinkers also   
   performed worse on a memory test later in adulthood. The findings suggest that   
   high doses of alcohol during adolescence may continue to affect the brain even   
   after drinking stops.   
    Further research is required to determine the applicability of these findings   
   to humans.   
      
   According to the World Health Organization, a growing number of adolescents   
   and young adults around the world engage in binge drinking, the consumption of   
   four (five for men) or more drinks over approximately two hours. Previous   
   research in humans has    
   shown an association between heavy episodic (binge) drinking in adolescence,   
   changes in myelin in several brain regions, and cognitive impairments in   
   adulthood. However, it was unknown whether alcohol was behind these brain and   
   behavioral differences or    
   if predisposing factors could explain the findings.   
      
   In this study, Heather Richardson, PhD, her graduate student Wanette Vargas,   
   BA, and colleagues at the University of Massachusetts, Amherst, compared   
   myelin in the prefrontal cortex -- an area of the brain that is vital to   
   reasoning and decision-making --   
    in young male rats given daily access to either sweetened alcohol or   
   sweetened water for two weeks. Animals that drank alcohol as adolescents had   
   reduced myelin levels in the prefrontal cortex compared with those that drank   
   a similar amount of sweetened    
   water. When the researchers examined the alcohol-exposed animals several   
   months later, they found that the animals continued to display reduced myelin   
   levels as adults.   
      
   "Our study provides novel data demonstrating that alcohol drinking early in   
   adolescence causes lasting myelin deficits in the prefrontal cortex,"   
   Richardson said. "These findings suggest that alcohol may negatively affect   
   brain development in humans and    
   have long-term consequences on areas of the brain that are important for   
   controlling impulses and making decisions."   
      
   The researchers also examined how adult animals that binged on alcohol as   
   adolescents performed on a test to assess working memory, the ability to hold   
   on to information for a short period. The more alcohol the rats consumed over   
   the two-week period as    
   adolescents, the worse they performed on the working memory task as adults.   
      
   "This study suggests that exposure to high doses of alcohol during adolescence   
   could exert lingering, if not permanent, damage to selective brain fibers,"   
   said Edith Sullivan, PhD, who studies the effects of alcohol on brain function   
   at Stanford    
   University and was not involved with this study. "This damage might underlie   
   persistent compromise of cognitive functions involved in learning and render   
   youth vulnerable for later development of alcohol use disorders."   
      
   Story Source:   
   The above story is based on materials provided by Society for Neuroscience.   
   Note: Materials may be edited for content and length.   
   null   
      
   Cite This Page:   
   MLA APA Chicago   
   Society for Neuroscience. "Heavy drinking in adolescence associated with   
   lasting brain changes, animal study suggests."    
   ScienceDaily.    
      
   ScienceDaily, 28 October 2014. .   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)