My father is a highly intelligent man who has worked a demanding job for 40 years. He has recently retired and seems to miss the mental challenges provided by work. He reads a bit but seems to be suffering from increased memory loss with regard to details. This is of concern to his family and I am sure himself, though it has not been openly discussed. I am sure there are ways to prevent this memory loss, or minimise its impact, but do not know how to proceed from here. Suggestions welcome.

At this stage, you may want to have your father see a local memory disorders specialist (usually a geriatrician, neurologist or psychiatrist). Early diagnosis and treatment of memory disorders has significant beneficial impact on prognosis. Your astute observation regarding your father's probable awareness of his condition is noted. High functioning individuals are among the first to note and be especially concerned about their cognitive dysfunction. He may become depressed and more withdrawn. It is an awkward situation, almost an "elephant in the room" scenario, where everyone is aware of, but no one mentions the problem.