The average retirement age of a physician is between 67 and 74 years old. Of those physicians who leave full-time work, 40% will continue with part-time medical practice. The overall average life expectancy in the U.S. is 79.3 years (females, 81.6 years; males, 76.9 years). That means life will end for 50% of all adults at that age. However, 50% will continue to live, maybe for many more years. College graduates also tend to have a greater than eight-year life expectancy over their counterparts (making up a significant portion of the latter half on the Gaussian curve).

Dementia is defined as the loss of cognitive capacity to the detriment of social functioning and individual living that lasts longer than six months. Though memory loss is an early component of this disorder, other symptoms may include executive functioning, language difficulties, working (immediate) memory, spatial memory and visual memory. The risk of someone getting dementia at 65 years old is 1 in 70. This increases to 1 in 5 by age 85. There are many causes of dementia, the most well-known being Alzheimer’s disease. Alzheimer’s and vascular dementia account for a large percentage of severe-onset dementia cases.

Dementia is not considered the normal process of brain aging. However, it is clear that the normal aging process also demonstrates progressive functional losses in perception, cognition and memory. A growing body of evidence seems to suggest a down-regulation of neuromodulatory system functions and increasingly poor signal-to-noise conditions (getting lost in the process). Traditional thought was that the machinery of thinking simply wore down (Mahncke et al., 2006).

It has been shown that four core biological factors may contribute to normal brain aging:

1. Reduced schedules of brain activity (going through the motion)
2. Noisy processing (inability to filter)
3. Weakened neuromodulatory control
4. Negative learning (lack of input)

These combined components may produce “negative” brain plasticity and decrease in function.

The hippocampus and parahippocampal area, key memory regions of the brain, have been shown to decrease in size with age—a normal occurrence (Raz et al., 1998). White matter changes in the brain have also been seen on MRI studies with increasing memory loss (Madden et al., 2009).

Despite these normal physical changes, the brain has the ability to alter its functional capacity throughout life, both in a negative and positive manner. For example, the same group of patients who demonstrated an age-related decrease in size of the hippocampus actually showed a subsequent increase in size with simple exercise for six months (AARP Bulletin, 2016). There are numerous stories of patients with traumatic brain injuries leading to impairment of motor function (Doidge, “The Brain That Changes Itself,” 2003). Over time, these patients were able to regain function by diverting the brain activity to another area of gray matter in the brain.

The idea of improving brain function by taking advantage of this unique ability of the brain to “respond” has created much interest in an attempt to provide tools to counter the normal aging brain and prevent the onset of dementia.

Several studies have shown consistent areas of decreased function with normal brain aging. Of these, a decrease in speed of the cognitive process was the most consistent change in the aging brain (Birren, 1965; Woods, 1980; Cerella, 1985; Salthouse, 1996). This was related to an increase in the deletion of random links in the memory network, creating a much longer memorial processing pathway (Craik, 1982; Rabinowitz, 1982).

Deficiencies in two important mechanisms were outlined:

1. Limited time mechanism: Older adults have a more difficult time performing higher-level operations within an allotted time.
2. Simultaneity mechanism: Decreased ability to consider concurrent task-relevant components because of the loss of earlier processing pathways (Salthouse et al., 1996). This correlated with findings that suggested difficulty of the aging brain to filter irrelevant material, subsequently interfering with the primary task. Speed of processing was the most age-related variance in cognitive tasking (Salthouse, 1985a, 1985b, 1996). However, the task was eventually accomplished in this group if time demands were eliminated. It is easy to understand how important these capacities are to the ability of the physician to provide patient care, especially in complex or urgent situations.

As the process of cognitive aging has been better understood, it is predictable that the question of reversibility and maintenance would be explored. With the assistance of environmental support—contextual guidance and mental crutches—memory was found to be improved with trigger words or phrases (Craik, 1986, 1987; Smith, 1977). Familiarity with the situation or the physical surroundings was also critical to minimizing age deficits (Craik, 1994; Park, 2000).

Numerous studies have shown the effectiveness of structured mental training programs in which prolonged cognitive exercises over six months demonstrated significant improvement in function (Mahncke, 2006; Shaffer, 2016; Mahncke and Connor, 2006). But could this be the argument for recertification? The hypothesis is that the use of structured brain exercises in an aging population can be utilized to create positive brain plasticity and potentially prevent, or delay, the need for expensive assisted living needs.

Specific repetitive functions (albeit with constant changing parameters—think patient care) within a daily activity can also elicit positive physical changes in the brain. For example, London cab drivers had larger hippocampi than London bus drivers because of their need to constantly assimilate new information and create complex spatial information to navigate routes (Maguire, 2006). Bus drivers obviously took repetitive routes. Bilinguals were also noted to have changes in the brain compared to monolinguals, specifically an increase in the left inferior parietal cortex (Mechelli et al., 2004). In addition, professional musicians demonstrated a significant increase in gray matter over non-musicians (Gaser et al., 2003). Even studying for exams produced changes in the parietal cortex of medical students before and after a test (Draganski, 2006).

Maybe even more relevant than compensation of brain function is the idea of maintaining cognitive health. It is clear that there are certain activities that have been shown to decrease the chance of dementia and maintain a high level of cognitive function.

Four recurrent areas of discussion include:

1. Mental stimulation
2. Physical exercise
3. Controlling chronic health issues
4. Nutrition

Cognitive health is an area that brings together the physical components of our lives, such as nutrition, exercise and control of medical conditions, with our mental health, such as stress control, mindfulness and humor.

Several things are obvious:

1. We have a much longer road to travel than our predecessors before we cross the finish line of life, especially as functioning physicians.
2. There are concrete things that we can do to provide the best chance that our journey continues to be productive and engaging.
3. These activities require a commitment that should’ve begun yesterday and should continue for the rest of your life.