It's inevitable. As we age, our bodies and our brains change, and not always like fine wine. Cognitive skills decline as part of the normal aging process and in turn, so do some of our financial management skills.

Research shows that financial decision-making peaks around age 53, and by age 60 our ability to process new information starts to slow. The shift happens at a different pace for everyone, and it can be accelerated by medical conditions such as Alzheimer's and dementia. While some people are capable of managing their own finances throughout their lifetime, others may find their skills...