Seasonal affective disorder
An extreme example of this desynchronization of the master clock can manifest as SAD. SAD is a type of depression that’s related to seasonal transitions. The most commonly cited cases of SAD are for the fall-to-winter transition. In North America, its prevalence is significantly influenced by the distance of one’s place of residence from the equator – with about 12 times the impact in Alaska versus Florida. Of note, a weaker effect of latitude has been recorded in Europe, where more settled populations have had thousands of years to biologically and culturally adapt to their seasonal patterns.
What can we do about our clocks being messed with?
The most common treatment for SAD is light therapy, in which patients sit or work under artificial lights in an early-morning period, to try to advance the chemical signaling that controls sleeping and waking. Alas, light therapy doesn’t work for everyone.
Another approach, with or without the lights, is to engage in activities early in the day that produce brain chemicals to contribute to bright and cheerful waking. Those “raring-to-go” brain chemicals include norepinephrine (produced when you encounter novelty and are just having fun), acetylcholine (produced when you are carefully paying attention and are in a learning and remembering mode), serotonin (produced when you are feeling positive and just a little bit euphoric), and dopamine (produced when you feel happy and all is right with the world).
In fact, you would benefit from creating the habit of starting every day with activity that wakes up your brain. I begin my day with computerized brain exercises that are attentionally demanding, filled with novelty, and richly neurologically rewarding. I then take a brisk morning walk in which I vary my path for the sake of novelty (pumping norepinephrine), pay close attention to my surroundings (pumping acetylcholine and serotonin), and delight in all of the wonderful things out there in my world (pumping dopamine). My dog Doug enjoys this process of waking up brain and body almost as much as I do! Of course, there are a thousand other stimulating things that could help you get your day off to a lively start.
If you anticipate feeling altered by a time change, you could also think about preparing for it in advance. If it’s the semi-annual 1-hour change that throws you off kilter, you might adjust your bedtime by 10 minutes a day for the week before. If you are traveling 12 time zones (and flipping night and day), you may need to make larger adjustments over the preceding couple of weeks. Generally, without that preparation, it takes about 1 day per time zone crossed to naturally adjust your circadian rhythms.
If you’re a little lazier, like me, you might also adjust to jet lag by not forgetting to take along your little bottle of melatonin tablets, to give your pineal gland a little help. Still, that pineal gland will work hard to tell you to take a nap every day – just when you’ll probably want to be wide awake.
And if, after reading this column, you find yourself still annoyed by the upcoming 1-hour time change, you might just look around at what’s happening out there in the world and decide that your troubles are very small by comparison, and that you should delight in the “extra” hour of sunshine each evening!
Dr. Merzenich is professor emeritus, department of neuroscience, at the University of California, San Francisco. He reported serving in various positions and speaking for Posit Science and Stronger Brain, and has also received funding from the National Institutes of Health. A version of this article first appeared on Medscape.com.