London, April 1 (IANS) Forgetting can be the result of an active deletion process in the brain rather than a failure to remember — a mechanism that helps us adapt our behaviour according to the surroundings, says a new study.
The findings could point towards new ways of tackling memory loss associated with conditions such as Alzheimer’s disease and other types of dementia.
“Our study looks at the biological processes that happen in the brain when we forget something,” said Oliver Hardt from University of Edinburgh in Scotland.
“The next step is to work out why some memories survive whilst others are erased. If we can understand how these memories are protected, it could one-day lead to new therapies that stop or slow pathological memory loss,” Hardt said.
The findings were published in The Journal of Neuroscience.
The study conducted in rats could also help scientists to understand why some unwanted memories are so long-lasting – such as those of people suffering from post-traumatic stress disorders.
Memories are maintained by chemical signalling between brain cells that relies on specialised receptors called AMPA receptors.
The more AMPA receptors there are on the surface where brain cells connect, the stronger the memory.
The team found that the process of actively wiping memories happens when brain cells remove AMPA receptors from the connections between brain cells.
Over time, if the memory is not recalled, the AMPA receptors may fall in number and the memory is gradually erased.
Blocking the removal of AMPA receptors with a drug that keeps them at the surface of the cell stopped the natural forgetting of memories, the study found.
One-two cup of coffee daily may cut colorectal cancer risk
New York, April 1 (IANS) Drinking black, decaf or even instant coffee daily can lower the risk of developing colorectal cancer, finds a study.
Moderate coffee consumption, between one to two servings a day, was associated with a 26 percent reduction in the odds of developing colorectal cancer after adjusting for known risk factors.
Moreover, the risk of developing colorectal cancer continued to decrease to up to 50 percent when participants drank more than 2.5 servings of coffee each day.
“We found that drinking coffee is associated with lower risk of colorectal cancer and the more coffee consumed, the lower the risk,” said lead researcher Stephen Gruber from University Of Southern California.
The study, published in the journal Cancer Epidemiology, Biomarkers & Prevention, examined over 5,100 participants who had been diagnosed with colorectal cancer within the past six months, along with an additional 4,000 participants with no history of colorectal cancer to serve as a control group.
A questionnaire also gathered information about many other factors that influence the risk of colorectal cancer, including family history of cancer, diet, physical activity and smoking.
The indication of decreased risk was seen across all types of coffee, both caffeinated and decaffeinated.
Caffeine and polyphenol compounds present in coffee can act as antioxidants, limiting the growth of potential colon cancer cells.
“The good news is that our data presents a decreased risk of colorectal cancer regardless of what flavor or form of coffee you prefer,” said study co-author Stephanie Schmit.
“While the evidence certainly suggests this to be the case, we need additional research before advocating for coffee consumption as a preventive measure,” said Gad Rennert from Clalit National Israeli Cancer Control Center in Haifa, Isreal.