You know the meaning of 'old sayings'. They use that when a saying has been proven to be true and have been passed around for years. One such old saying is "You learn something new every day".

We should be thankful that scientists are among the leading advocates of learning something new every day. Case in point: We've always believed that our brain cells die and stop regenerating once we get old.

Scientists, wanting to learn something new, have come up with studies that show new brain cell growth in adults, particularly in the hippocampus area of the brain. This area is where learning happens and where we store memories. Another study proved that the number of brain cells can be the same when you are a teenager and when you reach old age.

The brain does shrink in size over time. After reaching full size at around age 20, it begins to shrink by about 1% every year. The decrease in size is not due to neuron (nerve cell) death, but rather to changes of the dendrites that branch out from the neurons and the synapses (the spaces between adjacent neurons) between them.

The changes in the dendrites and the decrease in their numbers is the primary reason for a reduction in brain function as we age. Dendrites serve to connect the neurons to each other, in much the same way as entrance ramps connect surface roads to the interstate. If interstate entrance ramps are destroyed or in extremely poor condition, can you see how much harder it would be to continue on the path to your destination?

When nerve impulses are also destroyed or are in poor condition, they similarly have a hard time continuing on their path and reach a 'dead end'. The good news is that we don't have to suffer from brain cell deterioration as we get older.

Brain function in general and the dendrites in particular, deteriorate because of disuse. Which may bring to mind another 'old saying'; use it or lose it. This is especially true when it comes to our body. If neural pathways are not kept active, they will gradually decrease in strength and function until they are no longer able to perform properly.

For example, do you know why elderly people have a hard time sitting on the floor? It is because at some point in their lives, they stopped sitting on the floor. When that happens, the movements required to lower oneself to the floor are not used, and the electrical signals of many neurons required for that movement become too weak and cannot carry the signal and the brain's memory of how to sit down can no longer be performed.

We need to stay active mentally and physically to make new brain cells (called neurogenesis). It's interesting to note that stress can also prevent new brain cells from forming. So we need physical exercise to enhance it.

We can stay active mentally by doing mentally challenging things, like crossword puzzles and brain teasers. By staying mentally and physically active, we can make the brain continue generating new brain cells and reduce our changes of suffering from senility.

Warm regards,

Christian Goodman