Big head- less dementia!

While a big head may not always look attractive, there are some long-term benefits. The latest research from Germany indicates that people who have big heads may be protected against the depredation of dementia. In this study done in Munich, researchers followed people with big heads for many years. The patients had their head size measured, were given memory and cognitive skill tests followed by a brain scan to estimate the level of their disease. Over time, researchers discovered that individuals with Alzheimer dementia with the biggest heads had overall better cognition, memory and thinking skills compared to individuals with smaller skulls. A larger head was associated with better performance in the tests, even when individuals had similar amounts of Alzheimer's-related brain cell loss. 

The Munich researchers speculate that having a large brain means that there is more brain reserves, which buffers against dementia related brain cell death. The study looked at over 270 patients recruited from registries across Europe and North America.  The researchers observed that for every 1% brain cell death, an extra centimeter of skull size was associated with a greater than 6% score on the cognitive and memory tests.

So what does all this mean? 

It is not as if someone can increase brain size overnight because brain size is genetically determined. However, these researchers say that the first few years of life are critical for brain growth and by age 6, the brain will have reached almost 94% of its absolute size.

"Improving prenatal and early life conditions could significantly increase brain reserve, which could have an impact on the risk of developing Alzheimer's disease or the severity of symptoms of the disease," lead researcher Dr Robert Perneczky said.

Dr Simon Ridley, head of research for the Alzheimer's Research Trust, said, "Alzheimer's is a very complex disease, so we should be careful not to focus too much on a single risk factor, particularly as there is little we can do about the size of our heads.”

Added Dr Simon, "The researchers have also posed the idea that nutrition, injury or infection in early life can have an impact on brain reserve, suggesting that we should look after our brain from day one. Research is the only answer to dementia. We must invest in research now to deliver the treatments needed to avert the coming dementia crisis."

The two major criticisms about the study is that 1) no one has ever shown that having a small brain or body stature leads to an increased risk of dementia and 2) it is the function of particular areas of the brain which are far more important than size.