UC Irvine neurobiologists are providing the first visual evidence that learning promotes brain health – and, therefore, that mental stimulation could limit the debilitating effects of aging on memory and the mind.
Using a novel visualization technique they devised to study memory, a research team led by Lulu Chen and Christine Gall found that everyday forms of learning animate neuron receptors that help keep brain cells functioning at optimum levels.
These receptors are activated by a protein called brain-derived neurotrophic factor, which facilitates the growth and differentiation of the connections, or synapses, responsible for communication among neurons. BDNF is key in the formation of memories.
"The findings confirm a critical relationship between learning and brain growth and point to ways we can amplify that relationship through possible future treatments," says Chen, a graduate researcher in anatomy & neurobiology.
Study results appear in the early online edition of the Proceedings of the National Academy of Sciences for the week of March 1.
In addition to discovering that brain activity sets off BDNF signaling at the sites where neurons develop synapses, researchers determined that this process is linked to learning-related brain rhythms, called theta rhythms, vital to the encoding of new memories.
Theta rhythms occurring in the hippocampus involve numerous neurons firing synchronously at a rate of three to eight times per second. These rhythms have been associated with long-term potentiation, a cellular mechanism underlying learning and memory.
In rodent studies, the team found that both unsupervised learning and artificial application of theta rhythms triggered BDNF signaling at synapse creation sites.
"This relationship has implications for maintaining good brain health," says Gall, a professor of anatomy & neurobiology. "There is evidence that theta rhythms weaken as we age, and our discoveries suggest that this can result in memory impairment. On the other hand, they suggest that staying mentally active as we age can keep neuronal BDNF signaling at a constant rate, which may limit memory and cognitive decline."
Researchers are now exploring whether learning-induced growth signals decrease with age and, if so, whether this can be reversed with a new family of experimental drugs.
###
University of California - Irvine: http://www.uci.edu Thanks to University of California - Irvine for this article.
This article has been viewed 344 time(s).
 |
 Digg |
 FarkIt |
 |
 StumbleUpon |
 del.icio.us |
 |
In 1824, three years before he began to publish his famous "double elephant folio" The Birds of America, John James Audubon (1785-1851), the eminent artist of American birds and animals, created a drawing of a running grouse for use in the design for a New Jersey bank note.
The recent discovery of more than a thousand genes known as large intergenic non-coding RNAs (or "lincRNAs") opened up a new approach to understanding the function and organization of the genome. That surprising breakthrough is now made even more compelling with the finding that dozens of these lincRNAs are induced by p53, the most commonly mutated gene in cancer
A genetics research team based at The Children's Hospital of Philadelphia continues to discover recurrent translocations—places in which two chromosomes exchange pieces of themselves. As many as 1 in 600 persons carry balanced chromosome translocations, which involve no loss or gain of DNA.
Some trees growing in nutrient-poor forest soil may get what they need by cultivating specific root microbes to create compounds they require. These microbes are exceptionally efficient at turning inorganic minerals into nutrients that the trees can use. Researchers from France report their findings in the July 2010 issue of the journal Applied and Environmental Microbiology.
"Macho, macho man. I've got to be, a macho man. Macho, macho man. I've got to be a macho!" — The Village People
"If one finds something once, it's accidental. If it is found twice, it's puzzling. If found thrice, there is a pattern," the archaeologists Olle Hemdorff and Eva Thäte say.
"In laboratory tests, right- and left-handers associate positive ideas like honesty and intelligence with their dominant side of space and negative ideas with their non-dominant side," says Daniel Casasanto of the Max Planck Institute for Psycholinguistics in Nijmegen, Netherlands.
Often causing no symptoms in carriers of the disease, worldwide tuberculosis (TB) infects eight to ten million people every year, kills two million, and it is highly contagious as it is spread through coughing and sneezing.