Richard Thomas

This is from aarp.org
Understanding how and why brain functions change as we grow older may lead to new therapies and medications that could slow, stop, or prevent these processes altogether. (Note: If you click my name you will find that this is already figured out and an immediately available to solution)
Of course, other health problems—like high blood pressure, diabetes, or deafness—that people either have or develop as they grow older profoundly affect how their brains change with time.
Specific changes vary greatly from one person to the next, and may include the following, depending on their medical and psychological history:
•Brain mass shrinks
•Outer surface thins
•White matter decreases
•Chemical messengers decrease
Brain mass shrinks: Beginning in our 60s or 70s, some people's overall brain mass may shrink a bit. Certain brain areas shrink more than others, including the frontal lobe (important for mental abilities) and the hippocampus (where new memories are formed).
Outer surface thins: The cortex—the heavily ridged outer surface of the brain—thins slightly with age. This thinning is not, as scientists once believed, the result of widespread loss of brain cells. Instead, the thinning of the brain's outer surface is likely due to a decrease in synaptic connections (a process that starts when we're about 20 years old). Synapses are like intersections. They allow brain cells to communicate with one another and to form connections.
White matter decreases: Many studies have linked aging with decreases in the brain's white matter (so called because it's made up, in part, of myelin—a fatty, white substance). Myelin helps to improve communication between brain cells.
Research shows that changes in white matter are linked with changes in speed of cognitive processing. Cognitive processing includes memory, attention, action, problem solving, and decision-making abilities.
It's important to remember, though, that aging is not a process of decline. Many of our gifts and abilities—including wisdom and problem solving—improve as we age.
Chemical messengers decrease: As our brains age, they generate fewer neurotransmitters (chemicals like serotonin, which carry messages between brain cells), and have fewer receptors that lock onto these messengers. This change may have an effect on memory.
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As for McCain’s Computer Illiteracy

The importance of being able to use technology to facilitate one’s capability and increase efficiency is paramount. The ability for a president to make use of this tool and the Internet communications infrastructure is going to be essential to meet the demands. This skill results in an exponential increase in management capability and effectiveness.

The most essential skill for the president is communication, I think everyone will agree. Is their wisdom in choosing one without this skill that is dependant on others? This dependency creates the burden of latency, disrupts flow, and increase the probability of error.