Have you ever had a late night or had to stay up late to finish some work and found that the next day you are not quite at your usual perky self? After getting less sleep than normal you may notice that you are less focused, a bit fuzzy in your thinking and less able to recall things as easily as normal.

Some people (including myself!) know that drinking coffee late at night is a no-no because of its insomniac effect. What happens with coffee is that the caffeine competes with a naturally occurring brain chemical called adenosine. Our brain produces adenosine, which is taken up by specialized receptors to quieten down our brain in preparation for sleep. Drinking that cup of coffee at night allows the caffeine to compete for those same receptors as adenosine, allowing excess adenosine to remain circulating and we end up tossing and turning in bed, wishing we had had a cup of hot milk instead.

OK, so caffeine stops us from going to sleep, but why does lack of sleep affect our memory so much?

Researchers using mice studies seem to have found a biological explanation.
In a study published in the Journal Of Neuroscience, researchers looked at the role of adenosine and memory in sleep deprivation. It turns out the effect is the same whether you are a fruit fly, a mouse or a human being. In sleep deprivation you end up with more adenosine floating around than normal, just in the same way as when caffeine blocks of adenosine uptake.

Glial cells, the brain cells that support neurons, produce adenosine. The receptors for the adenosine are located in the hippocampus the specialized area associate with memory and learning.

Losing the equivalent of half a night’s sleep for just for one night was shown to produce a significant impact on a mouse’s ability to form memory, and the neurons involved were less plastic than normal, meaning normal neuronal transmission was compromised.

Getting enough sleep is essential for us to think clearly and have normal memory function. This is true for both children at school and for adults in the workplace. We need enough shuteye to help our brain work at its best.

This was also discussed in relation to our children in a recent article in the New York Times. The author asked the question about how much do our children sleep and are they getting enough sleep.

This is especially pertinent for adolescents whose brains undergo some radical changes during their teens right up to the time when brain development is complete in their early twenties.

Sleep researchers report that this age group requires between 8 to 9+ hours sleep per night, yet many get far less than this, and trying to catch up on weekends doesn’t work.
The result? Many high school students are in class already sleep deprived and in a less than perfect state in order to learn. Not only are they less efficient in taking in new information, they also need sleep to consolidate their learning and form memories. All of which adds up to a negative effect on those all important school grades.

When it comes to learning and memory, it boils down to the fact we really do need to get enough sleep.

Refs:
C. Florian, C. G. Vecsey, M. M. Halassa, P. G. Haydon, T. Abel. Astrocyte-Derived Adenosine and A1 Receptor Activity Contribute to Sleep Loss-Induced Deficits in Hippocampal Synaptic Plasticity and Memory in Mice. Journal of Neuroscience, 2011; 31 (19): 6956 DOI: 10.1523/JNEUROSCI.5761-10.2011

http://www.nytimes.com/2011/05/24/health/24brody.html

Have you ever wondered why it is that as people get older they tend to reminisce more?
Have you also noticed that older people tend to complain more about how hard it is for them to learn new things?

It’s not just the fact that older people have more to remember and reminisce about, it may be that it is easier for them to recall an older memory than it is to create a new one.

When we form a new memory the information has to be received and then processed by the area of out brain called the hippocampus.
As we get older, those neural pathways bringing the information to the hippocampus start to get degraded. So if there are more potholes in the road, it is harder for the brain to get the information to the processing plant to lay down a new memory.

Professor Yassa at John Hopkins University has been using 3 different forms of MRI scans (structural, functional and diffusional) to study how well different areas of the brain communicate and distinguish between old, new and similar information and the differences between the brains of younger College students and a group of 60 to 80 year olds.

What he found was that the older subjects were less able to recognise something that was similar to something they had recently seen. Images had also to be very different, to be picked up as being new. This was attributed to the older group having a more degraded pathway of the information getting to the hippocampus.

So next time you forget where you parked the car. It may not just be because you didn’t pay attention at the time, but also that your brain is relying more on previous memories of where you parked previously, which may not be of much help to you this time round!

Ref:

M.A. Yassa, A. T. M., S.M. Stark, C.E.L.Stark (2011). “Age-related memory deficits linked to circuit-specific disruptions in the hippocampus.” Proceedings of the National Academy of Sciences,.

Our weight matters.

How many of us today struggle with weight issues? We appear obsessed with seeking a way, any way, to help us to lose those excess kilos. Just look in any book-store and there are dozens of books instructing us how to lose weight. We have nightly current affairs programs discussing the latest “secrets” or diet craze.
We even have television programs documenting weight loss as a competition, with “The Biggest Loser”

Why is obesity a concern for our brain?

Being overweight or obese carries a number of significant health issues. Not least of which include Type two diabetes and heart disease.
Our calorie dense diets and sedentary lifestyle compound the problem.

One of the other issues less well known about from being overweight is the effect it has on our brain. Our memory and thinking skills are impaired when we are overweight.

Obesity is associated with a shrinking brain. The total brain volume is reduced and the amount of grey matter (our neurons in our cortex) is less dense.

Worse still, being overweight in middle age (BMI 25-40) is associated with a 70% increase risk of dementia. If you are obese, make that x 4 the risk. There is also a gender bias, with women being particularly at risk.

Apart from the increased risk of diabetes and vascular disease, both of which are risk factors for dementia, being obese means the body and brain are subjected to higher levels of inflammation. The fatty tissue itself secretes inflammatory cytokines and other chemicals.

So, is weight loss the answer?

In a nutshell, yes.

This has recently been confirmed by a study on people who have undergone bariatric surgical procedures to achieve weight loss.
Bariatric medicine deals with the cause, prevention and treatment of obesity.
Increasing numbers of people have been resorting to surgery in a desperate attempt to lose weight when all other avenues appear to have failed.

The surgery often produces significant weight loss over a relatively short period of time. This made this type of procedure ideal as a means to study what impact if any, the surgery produced on memory and cognitive function of the obese.

A total of 150 people participated in the trial. 109 underwent a bariatric procedure.
Prior to the surgery many of the group exhibited impaired performance on cognitive testing.

In just twelve weeks postoperatively, these results had improved from slight impairment to returning to a normal range.

The study will continue with repeated testing at one year and two years postoperatively.

This is obviously really good news to show that such cognitive impairment can be reversed with successful bariatric procedures. Further studies will look to see whether the same sort of result can be achieved using conventional weight loss techniques of diet and exercise. It could also be, that as successful weight loss is achieved, we are more likely to remain motivated to keep eating more healthily and to keep exercising, both of which are really important factors to help us retain our cognition.

The prospect of being able to improve your memory and thinking skills by keeping your weight in the healthy weight range is a very powerful motivator. Plus it reduces that risk of dementia in later years.

Many of us worry about our health and our brain as we age, the impact of our genes and what we can do to help ourselves.
But it looks as if ensuring we keep to a healthy weight range across our lifespan is a really great way to start.

refs:

John Gunstad et al. Improved memory function 12 weeks after bariatric surgery. Journal of the American Society for Metabolic and Bariatric Surgery, 2010 DOI: 10.1016/j.soard.2010.09.015

http://opinionator.blogs.nytimes.com/2010/04/20/brain-damage/

Berries are loaded with powerful antioxidants and blueberries in particular have exceptionally high levels of flavonoids. The deep blue colour of blueberries comes from the anthocyanin they contain and it is this sub-group of flavonoids, which have been found in other research to be beneficial in terms of helping us to maintain our memory and cognitive function.

Enjoying blueberries and the other deeply pigmented red berries and stone fruit has been recommended for a while, as being a useful to help protect us against dementia.
New research from Harvard now indicates that regularly eating berries may also lower your relative risk of developing Parkinson’s disease.

Parkinson’s disease is a neurodegenerative disease primarily affecting motor function but is also associated with a 30% incidence of dementia.

In this study, the researchers used a dietary questionnaire for 49,281 men and 80,336 women. They then analysed the association between amount of flavonoid intake from food and the risk of developing Parkinson’s disease.
They also analysed the consumption of five major food sources known to be high in flavonoid content i.e. berries, apples, red wine, tea, oranges and orange juice. The participants were followed over 20 to 22 years.

What were the findings?

In the male group it was found that those in the top 20% tier of flavonoid consumption were 40% less likely to develop Parkinson’s than those in the bottom 20% tier of consumption.

Interestingly in the ladies group, no such relationship between flavonoid consumption and risk of Parkinson’s was demonstrated.

However, in examining the effect of the different subgroup of flavonoids, it was found that regular consumption of anthocyanin from berries was associated with a lower risk of Parkinson’s disease in both men and women.

The message: eat more berries

This is the first human study to look at the link of flavonoids, (especially anthocyanin) in food and the risk of developing Parkinson’s disease. The findings suggest that men and women who regularly eat berries may have a lower risk of developing Parkinson’s disease. It also appears that men can to continue to further reduce their risk by eating a greater proportion of other flavonoid rich foods in general, including apples and oranges, tea, red wine (in moderation) and chocolate.

Ref:
Xiang Gao, MD, PhD Harvard School of Public health. American Academy of Neurology (2011, Feb17)

What does having high blood pressure, a big belly, high blood sugar, high triglycerides, low HDL cholesterol and high LDL cholesterol give you?

The answer?

Metabolic syndrome.

Metabolic syndrome is as the name suggests, a syndrome made of up a combination of three or more or the above risk factors. It is linked to having a higher risk of heart disease.

But if you look at each of these risk factors on their own, they are all risk factors for dementia. So it is probably no surprise to learn that someone with metabolic syndrome has a higher risk of developing memory loss, as they get older.

Recent research confirms the risk of memory loss from metabolic syndrome

A French study recently published in the journal Neurology tested a population of over 7000 people from three French cities looking to identify those with metabolic syndrome.

They found that 16% of the cohort met the criteria for metabolic syndrome. All of the participants took part in a series of memory and cognitive function tests two and four years later.

The tests included a memory test, a visual working memory test and a word fluency test.

What they found was that those 16% with metabolic syndrome

• Were 20% more likely to show cognitive decline
• Were 13% more likely to have cognitive impairment with the visual working memory test
• Were more likely to have poorer working memory if they had high triglycerides and lower HDL cholesterol
• Were associated with poorer visual working memory and word fluency if they had actual diabetes (not high blood sugars alone)

The key message from this study is that having metabolic syndrome is a major risk factor for memory loss because of the multiplier effect of the associated components, which go to make up this condition.

It seems fairly obvious that good management of those with metabolic syndrome is vital to preserve their cognition for advancing age.
What is encouraging though, is that many of the individual components can be relatively easily managed with good patient education and self-motivation.

High blood pressure can be addressed through losing weight, increasing physical activity, and medication if necessary.
High blood sugars and diabetes require dietary intervention and education, plus normalising weight, increasing exercise and using medication if required. Tight glycaemic control is the aim.

Blood lipids require follow up with repeated blood levels, dietary advice and intervention, exercise and medication as required.

Those big bellies may also require help with nutritional advice, exercise and follow up.

There are a number or recurrent themes of management which boil down to two of the key elements used in improving brain fitness, namely
good nutrition and exercise.

Better management of the metabolic syndrome will help to slow down age related memory loss or delay the onset of dementia in this high-risk group.

Ref:
C. Raffaitin, C. Féart, M. Le Goff, H. Amieva, C. Helmer, T. N. Akbaraly, C. Tzourio, H. Gin, P. Barberger-Gateau. Metabolic syndrome and cognitive decline in French elders: The Three-City Study. Neurology, 2011; DOI: 10.1212/WNL.0b013e31820b7656