Binge-Drinking Brain Damage
'Binge-drinking' when young alters our brains' development for life, new research reveals.
All of our bodily processes rely on communications between cells that are coordinated by the brain. It acts like a huge telephone switchboard packed full of special structures, called synapses, that connect nerve cells, known as neurons, to the other cells they want to talk to. We have trillions of synapses whose connections refine as we grow up, and become essential to learning and memory.
"During early development there's a lot of synaptic growth, and then from your teens up to mid-twenties there is a lot of maturation of those synapses, making it an important period of development," says study-author Duke University and Durham V A scientist Mary-Louise Risher.
To explore the effects of heavy drinking during this developmental stage, the researchers, writing in Alcoholism: Clinical and Experimental Research, subjected adolescent rats to repeated drinking binges, and then analysed their brains in adulthood.
By electrically stimulating slices of the animals' hippocampi, brain areas crucial for learning and memory, they were able to assess how the nerve cells responded. Tissue from animals previously exposed to alcohol binges showed increased levels of activity. This could be detrimental to the learning process.
"This area [the hippocampus] is also important for episodic memory. Things like - Where did I park my car? Where did I leave my keys? - the what, where and when," says Risher. "It's likely that these processes are going to be interfered with because of this hyper-excitability"
As well as affecting memory, the brain is physically altered by alcohol. All neurons have critical parts called dendritic spines that allow them to connect. When we are younger, these spines are long and spindly, becoming shorter and wider as we mature. In alcohol-exposed brains, there is a higher ratio of immature to mature spines, which could account for the increased activity the team observed.
Unfortunately this important period of brain development, which is highly susceptible to drinking damage, coincides with legally being allowed to drink and for many the novelty of nightclubs and testing tolerance.
"We hope to come up with a lot of really interesting work that can inform the public," Rischer concludes. "I'd like to think this will educate them [young drinkers] in a way to make good decisions."
Listen to Mary-Louise Risher explaining to Heather Douglas how alcohol affects the developing brain:
Binge Drinking Brain Damage