Tag Archives: memory

Where Are My Car Keys?

Who hasn’t asked themselves that question?

My car keysphoto © 2007 Reiner Schubert | more info (via: Wylio)

On an increasingly frequent basis, I find myself utterly at a loss for what movie I saw last week or where I put my cell phone. I’ve even accused my phone of teleportation – and then seriously questioned the health of my brain.

How is it I can remember some trivial and insignificant detail from 20 or 30 years ago and not what I had for dinner two days ago? Am I losing my mind – is this the first dreaded sign of Alzheimer’s?

Life is a challenge for most people because they have never been this age before, at least not that they remember. I am an expert at being 40 (and unfortunately at being 50), but 55 remains a mystery, although not for long.

The brain of most people weighs about three pounds – even Einstein’s. It is made of something like 100 billion neurons. Each neuron connects to hundreds of other nerve endings. The connections in your brain number roughly 1 quadrillion (that’s 1000 trillion or 10 to the 15th power). My brain hurts just thinking about that number.

A fatty substance called myelin insulates these connections and acts like the plastic coating on a wire. Short circuits are called seizures. Fortunately, you don’t need to understand the brain’s owner’s manual to operate one.

With aging, some neurons die. You start with all you get and go down from there. What a completely depressing thought. There is a tiny but measurable decrease in brain mass with increasing age. As these cells die, their connections are lost, resulting in some data loss. The brain continually rewires itself, constantly establishing new “work-around” for the lost cells. It is actually more remarkable what we remember, rather than what we forget. Remember this is a biological system, not a supercomputer.

Studies have shown that as brains age, long-term memories are maintained the best. Recent or new memory formation is the most affected. Several long philosophical ruminations occur at this point, but you may peruse that on you own.

Now it gets interesting. Everyone has heard we live in a small portion of our brain, something like 30 percent. There is a huge range of “normal” among adults with healthy brains. What feels like normal to me might feel like the mother of all hangovers to some master mathematician or particle physicist.

We have been collecting vast amounts of data our whole lives. Much of the data is meaningless. Do you really need to remember every parking space you selected in your life or every word you’ve spoken or heard? The data is there, somewhere. Since it is never used, it is given low priority by the brain. The less unique the memory, the harder it is to retrieve. The less a memory is used, the harder it is to recall. Use it or lose it (your mind that is).

The sheer mass of data makes us all feel like an Alzheimer’s candidate. Everyone forgets where he or she parks, but no one forgets the color of their car.

Brain health is a lot like body heath. The brain likes to be exercised (Sudoku anyone?). It’s utterly dependent on good blood flow and oxygen, so we want to keep atherosclerosis away. Everyone talks about classical music exposure in utero, but it’s hard to fix that now. Personally, I think rock works better – it makes mom move, which keeps the blood flowing.

These mental glitches are part of the human experience. One study of neurologists found 60 percent had what they considered real symptoms of brain disease – and these guys are pretty smart. They could lose a few neurons and miss them less than I would.

Fortunately, dementia is not hiding behind every lost car key or car. In fact, considering the complexity of the brain, it is perhaps more amazing that it works as well as it does.

Take care,

Dr. B