It Has Come To My Attention

My Photo
Name: Simon Quellen Field
Location: Los Gatos, California, United States

See these newspaper articles

Science Toys Toys I bought for myself Ingredients Syndication feed

Friday, March 10, 2006

A Hunger for Learning

There is a hormone called ghrelin that is produced in the lining of the stomach when it is empty. This hormone travels through the blood into the brain, where it triggers receptors in the hypothalamus to make you feel hungry.

If you feel hungry, it is a good bet that there is ghrelin getting to your brain.

The hormone has that funny name because it regulates the release of growth hormone. (Growth Hormone RELease, folowed by the "in" suffix used for hormones.)

While the benefits of human growth hormone are well known to athletes and geriatricians, the effects of ghrelin in the brain are what I am interested in at the moment, because they seem to reach beyond the appetite stimulus, and affect learning and memory.

I go on a low calorie diet every February, and one of the things I have noticed during those periods (beside feeling hungry all the time) is that I seem to be more alert, and paradoxically feel like I am full of energy. It now seems that these mental benefits are more than just delusions of a starving brain.

Now, there also seems to be evidence that hunger might also increase anxiety and aggression, although I have not noticed those effects while on my diet. But if you do, there is a quick cure in the refrigerator.

Just don't eat yourself stupid.

Building a better brain

There is a class of proteins in the brain called neurotrophic factors.

Two of them are particularly interesting to me at the moment. They are GDNF and BDNF. What interests me about them today is that they are produced in the body as a result of exercise, such as walking for an hour a day.

The effects of BDNF and exercise are an increase in brain cells, and an increase in the branching of the brain cells that contribute to brain function and memory.

One researcher, Carl Cotman, refers to BDNF as "brain fertilizer". Rats and mice that are allowed to exercise as much as they like perform much better on memory tests than sedentary rats and mice, and their brains show much higher levels of connectivity.

The other protein, GDNF, protects brains from Parkinson's disease, Alzheimer's disease, and Amyotrophic Lateral Sclerosis (ALS).

So why am I interested in these proteins today? Thursday is the day of the Google Weekly Walk. A bunch of us Googlers meet in the building 42 lobby at 3:00 pm, and then take an hour long walk around the lake by the golf course.

It's a beautiful walk by the stream and the little lake, and you get to talk to very smart people about just about anything, people who you might not otherwise have any occasion to talk to.

And you build a better brain at the same time...