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The drug is called guanfacine and clinical trials are underway at Yale University in Connecticut to confirm its beneficial effect in enhancing so-called working memory in older adults. Yale neurobiologist Amy Arnsten says working memory is the building block of all higher cognitive functions, underlying things like abstract thought and executive functions including multitasking - juggling several activities at once. Arnsten says working memory starts to decline in a persons 40's. These deficits ..begin in middle age in both monkeys and humans and get steadily worse as we grow older," Arnsten explained. "So this is very relevant for very demanding jobs and being able to keep those careers. And its even important for basic things like managing our finances, our medical care as we get older."
Clinical trial
Neurobiologist Arnsten says working memory involves neurons - brain cells - in a highly-evolved area of the brain called the pre-frontal cortex. In order to hold on to information, she says the neurons have to excite each other through network connections. But as we age, Arnsten says the neurochemical environment changes and the connections between the cells loosen. The result is that people are not able to remember things as well as they could when they were younger. Thats what researchers, led by Arnsten, found in experiments with rhesus macaques. Two of the monkeys were young, two were middle aged and two were elderly. Investigators found the neurons of all the animals fired similarly in different areas of the prefrontal cortex when they were first shown a favorite treat.
But that neuronal activity declined in the older animals when they had to wait for a short period and tried to remember where the snack had been hidden. Scientists noted the decline in brain cell activation was proportional to the monkeys age. Arnsten says researchers then gave the older animals the blood pressure drug guanfacine and the differences in neuronal firing between the older and younger primates narrowed. What was so encouraging about our finding was that when we corrected the neurochemical environment, we were actually able to restore network firing," Arnsten explained. "And weve shown that these same drugs, when given systemically, can improve working memory.
Causes of memory decline
Bioactive ingredients found in cocoa sharply reversed age-related memory decline in a group of volunteers, scientists reported on Sunday. The compounds, called flavanols, were taken in a specially prepared cocoa drink, according to an experiment published by the journal Nature Neuroscience. Over three months, 37 healthy volunteers aged 50 to 69 had a daily drink containing either a high dose of flavanols — 900mg — or a low dose, 10mg. The scientists carried out brain imaging, measuring blood volume in a key part of the hippocampus called the dentate gyrus, a region of memory formation whose performance typically declines as one ages.
They also carried out memory tests before and after the volunteers started with the drink. The tests entailed a 20-minute pattern-recognition exercise designed to assess a type of memory controlled by the dentate gyrus. The high-flavanol group notched up major memory improvements and an increase in blood flow to the dentate gyrus. “If a participant had the memory of a typical 60-year-old at the beginning of the study, after three months that person on average had the memory of a typical 30 or 40-year-old,” said Scott Small, a professor of neurology at Columbia University Medical Center in New York. More work, in a bigger group, is needed to verify the early findings, he said.
Flavanols have excited great interest. They dangle the possibility of tackling age-related memory loss in the world’s fast-growing elderly population, but without using drugs. The compounds exist in grapes, blueberries and other fruit, as well as in some vegetables and teas, but the type of flavanol and the amount vary widely. Previous studies in mice showed that the class of flavanols found in cocoa boosts the performance of the dentate gyrus. “The dentate gyrus in humans and mice are very similar,” Small said in an e-mail. “I suppose that our study does show, for the first time, that flavanols improves the function of humans’ dentate gyrus, particularly in ageing humans.”
The findings apply to normal memory loss — things such as forgetting the names of new acquaintances or where one has left one’s glasses — which usually becomes noticeable when people reach their 50s or 60s. The findings do not apply to memory loss caused by disease, such as Alzheimer’s. The cocoa drink was prepared by a large US food corporation, which also partly supported the research. The study is published in a peer-reviewed journal. The firm used a proprietary process to extract flavanols from cocoa beans. Under conventional processing, most of the flavanols are lost from the raw plant.
Small said it was still too early to make dietary recommendations for flavanols, but “certainly I would not suggest that people consume more chocolate.” “That would be a mistake,” he said. “Very simply, the amount of flavanols that are found in chocolate is minuscule compared to the very high amount of extracted flavanols that our subjects consumed. The same is true for most other foods or teas,” Smith said. “Hopefully, in the future a food source or a specific diet will be identified that contains very high amounts of the specific flavanols we studied.”
Cocoa clue to reversing memory loss - Taipei Times
Akinwumi Adesina, speaking at the 2014 Cocoa Summit in Abuja on Monday, said Nigeria expects to generate $1.3 billion in revenue from cocoa exports this year, a 45 percent jump from two years ago. He said Nigeria is on track to produce 370,000 tons of cocoa this year, compared to 250,000 tons in 2012.
Abuja, Nigeria
Adesina also said the government is committed to boosting cocoa production to 500,000 tons by next year and to 600,000 tons by 2016. Nigeria is the fourth biggest cocoa producer behind Indonesia, Ghana and top grower Ivory Coast.
Nigeria Expects to Export 1.3B in Cocoa in 2014
The US and Japanese team found that the brain "doubles up" by simultaneously making two memories of events. One is for the here-and-now and the other for a lifetime, they found. It had been thought that all memories start as a short-term memory and are then slowly converted into a long-term one. Experts said the findings were surprising, but also beautiful and convincing.
'Significant advance'
Two parts of the brain are heavily involved in remembering our personal experiences. The hippocampus is the place for short-term memories while the cortex is home to long-term memories. This idea became famous after the case of Henry Molaison in the 1950s. His hippocampus was damaged during epilepsy surgery and he was no longer able to make new memories, but his ones from before the operation were still there. So the prevailing idea was that memories are formed in the hippocampus and then moved to the cortex where they are "banked". The team at the Riken-MIT Center for Neural Circuit Genetics have done something mind-bogglingly advanced to show this is not the case.
The human brain is a biological masterpiece
The experiments had to be performed on mice, but are thought to apply to human brains too. They involved watching specific memories form as a cluster of connected brain cells in reaction to a shock. Researchers then used light beamed into the brain to control the activity of individual neurons - they could literally switch memories on or off. The results, published in the journal Science, showed that memories were formed simultaneously in the hippocampus and the cortex. Prof Susumu Tonegawa, the director of the research centre, said: "This was surprising."
The experiments were performed on mice but are thought to apply to human brains too
He told the BBC News website: "This is contrary to the popular hypothesis that has been held for decades. "This is a significant advance compared to previous knowledge, it's a big shift." The mice do not seem to use the cortex's long-term memory in the first few days after it is formed. They forgot the shock event when scientists turned off the short-term memory in the hippocampus. However, they could then make the mice remember by manually switching the long-term memory on (so it was definitely there). "It is immature or silent for the first several days after formation," Prof Tonegawa said.
'Strong case'
