From the Editor
When I began medical school in 1982, the brain was often referred to as a “black box,” a description meant to convey how little we knew about brain function and circuitry. We have learned much since then, and many of the scientific publications on brain-related research that flood my inbox each month have words in the title that I have never heard of before. I try to keep up, but I often feel as though I am trying to bail out the Titanic with a cup. Amidst this information explosion, there remain core principles that are well established and can help facilitate the health of our brain. On my website, Brain-Health.co, I have a link to a page where I list “Ten Ways to Grow a Healthy Brain.” I do my best to follow these myself, and I routinely discuss these with my patients. I invite feedback to lengthen this list and encourage all of us to work toward continued brain health.
Arguably one of the most important requirements for good brain health is a good night’s sleep. Sleep is a primary mammalian function that has been evolutionarily conserved, and ideally each 24-hour day includes a defined period for sleep. There is tremendous individual variation in the number of hours a person requires to achieve the benefits of a good night’s sleep, ranging from 5 to 10 hours every night. During sleep, the brain’s energy utilization decreases, and the brain assumes a restorative posture, removing unwanted waste products and replacing the adenosine triphosphate (ATP) energy supply used up during the day. Sleep is a time for health promoting immune processes to occur, and for the endocrine system to recalibrate.
Significantly, the information and experiences of the day are consolidated in the various specialty areas of the brain’s cortical regions from the brain’s hippocampus, where they are stored temporarily during the day. Throughout the day, the hippocampus serves a function much like the random access memory (RAM) of a computer—without the storage of the day’s events in the cerebral cortex that occurs during sleep, the memory of these events will be impaired and less enduring.
To continue our computer analogy, our daily experiences and learning is temporarily saved in RAM, with the expectation that we will “save” this information to the hard drive before we shut off our computer. If we forget to save the information, it disappears from RAM after the computer is powered off. Hence the inefficiency of studying all night for an exam—we may pass the test, but we will not retain much of the material.
Sleep disorders are very common. Approximately one-third of the US population report symptoms of insomnia. Over the past 30 years sleep studies have improved greatly, and it has become routine to diagnose and treat sleep disorders like sleep apnea—everyone knows someone who uses a cPAP (continuous positive airway pressure) machine during sleep, often with a significant improvement in wakefulness the following day. Sleep dysfunction is complex and can be caused by many diverse factors: genetics, environmental, stress, medical conditions, psychiatric disorders, parenting newborns and children, ingestion of stimulants (caffeine, theophylline, theobromine, methylphenidate, amphetamines, modafinil, pseudoephedrine, and cocaine to name a few), pain, obsessive/ruminative thinking, excitement, and anticipation. Although we have quite an armamentarium of sleep hypnotics, the most effective treatment we have to offer as clinicians is education about good sleep hygiene.
The most commonly utilized over-the-counter sleep aid in the US is diphenhydramine (Benadryl®). Most products sold at your local pharmacy that promote improved sleep contain diphenhydramine as one of the ingredients. Diphenhydramine has two pharmacological properties that can cause significant morbidity if taken daily for prolonged periods of time—antihistamine and anticholinergic. The antihistamine effect is what causes sedation; however, over time the histamine receptor de-sensitizes, so it becomes less effective. Moreover, chronic use of an antihistamine causes weight gain in many individuals. The chronic anticholinergic effect increases cognitive impairment, constipation, dry mouth, and urinary retention.
1. TED: Ideas Worth Sharing. Dan Buettner. https://www.ted.com/speakers/dan_buettner. Accessed June 17, 2019.
2. Blue Zones. https://www.bluezones.com/live-longer-better. Accessed June 17, 2019.
3. Benson H. The Relaxation Response. New York, NY: William Morrow; 1975.
4. UMass Medical School: Center for Mindfulness. History of MBSR. https://www.umassmed.edu/cfm/mindfulness-based-programs/mbsr-courses/about-mbsr/history-of-mbsr/. Accessed June 17, 2019.
5. Kabat-Zinn. Full Catastrophe Living: Using the Wisdom of Your Body and Mind to Face Stress, Pain, and Illness. Brooklyn, NY: Delta Publishing; 1991.