Experts used to think that as we aged, the brain progressively shrank (atrophied), slowly robbing us of our mental faculties.
But careful brain cell counts have demonstrated that this is not true. In fact, with normal aging, brain structure actually becomes more complex. Neuroscientists have concluded that the speed at which we think slows with aging, but our ability to think actually improves.
We used to refer to that as the "wisdom of the aged." You might want to share that little pearl with your children and grandchildren.
Throughout our lives, the brain is building new connections and neural fibers (called synapses and dendrites, respectively). This continuous molding process is known as brain plasticity. One study examined the brains of people who were 100 years old or more and found that plasticity was still occurring.
Synapses and dendrites are the parts of brain cells most vulnerable to free-radical damage. With healthy brain aging, most of the damaged connections are repaired. This is why we often see people in their 90s who are mentally sharp.
The bottom line: Normally, in healthy individuals, the brain does not seriously deteriorate with age, and neurodegenerative diseases are certainly not inevitable.