The Neuroscience of Summer Vacation

As the air warms and the schools let out for the summer, our minds turn towards vacation. Whether it be a quick escape to the beach, a prolonged trip to another city or country, or a trip to a cabin in the woods, a summer vacation can have a multitude of benefits for the health of your brain through a bit of relaxation, some outdoor activities, and a bit of change from the usual rhythms of life.

There is no shortage of evidence that even short vacations imbue significant improvements on health and well-being.^[1] The mental fatigue that comes with extended work hours and prolonged engagement negatively impact our brain’s ability to execute important tasks like planning^[2] and critical thinking. In fact, recent research has revealed that mental fatigue is the brain’s enemy in such important domains as creative problem solving. The elusive, insightful realizations that we often call ‘ah-ha’ moments,^[3] are directly impeded by over-engagement^[4] like that which we experience from working constantly without proper breaks and vacations. Moreover, the repetitive rhythms of the work routine reduce our exposure to new and novel experiences and environments like those we find ourselves in during a vacation. Novel environments have been shown to enhance the overall function of brain regions associated with learning and memory, creativity and critical thinking.^[5] In fact, these new and stimulating environments may promote the growth of new brain cells and stave off the neurodegeneration associated with depression and the cognitive decline of dementia, Alzheimer’s disease and Parkinson’s disease.^[6] So, this summer break: go somewhere new, change your environment and give your brain a much-needed boost.

Vitamin D, the Brain and Beyond

Often called the ‘Sunshine Vitamin,’ vitamin D is an essential component of a functioning human body and brain. From muscular function and immune system health to bone metabolism and mental health, adequate amounts of vitamin D are a necessary ingredient of a healthy life. Being a byproduct of sun exposure, vitamin D deficiency is particularly prevalent during the winter months (and beyond, for those toiling away in an office during the daylight hours). The correlation between vitamin D deficiency and mental illness is profoundly consistent, with UK doctors reporting that at least 83%^[7] (and in one study, 100%)^[8] of psychiatric inpatient hospitalizations were correlated with clinically deficient vitamin D levels. Depression, chronic stress and anxiety, and general cognitive dysfunction have all been associated with vitamin D deficiency; so, a bit of time in the sun can do more than a little good for the emotional brain.

In addition to sun exposure, exercise is an excellent driver of vitamin D production. Many studies have found a strong positive correlation between adequate vitamin D levels and physical activity.^[9] In the frenetic pace of modern life, finding time for exercise can be challenging – so, what better time to boost your vitamin D with a sunshine hike than summer vacation ? In the short-term, increasing vitamin D is associated with improved moods and measures of psychological well-being, as well as enhanced functions of synaptic plasticity (the means by which our brains learn and integrate new information).^[10]

In the long-run, these vitamin D boosts may do more to maintain a healthy mind than once given credit for. Recently, researchers have found a significant correlation between the likelihood of developing dementia and clinically low vitamin D levels.^[11] European nations in particular^[12] (and perhaps most significantly the UK)^[13] are rife with elderly populations exhibiting low levels of Vitamin D due to a lack of sun exposure and poor dietary sources of the vitamin. Aside from dementia, low serum vitamin D has also been found to correlate with increased incidence of Alzheimer’s disease and poor cognition.^[14] Thus, some sunbathing will give a golden glow to your skin and your brain (and a healthy meal of mushrooms, packed full of the vitamin, couldn’t hurt either).

Hike, Swim, or Run Your Way to a Healthy Brain

Aside from an opportunity to relax and unwind, a vacation break can be a great time to take a moment to exercise. The busy pace of work life can leave us with little time to engage in sport, and while it may seem counterintuitive to go for a run when you could be on the beach, the benefits of taking a bit of time for some physical activity during your break from work can be profound for your brain health. A recent meta-analysis of hundreds of studies examining the size of the hippocampus (the region of the brain controlling memory and learning) found that even moderate aerobic exercise prevented age-related deterioration.^[15] While the hippocampus slowly shrinks with age in the general population, people who regularly made time for moderate aerobic exercise (such as running, hiking, or swimming), showed much slower rates of this effect, indicating that their learning and memory faculties would remain intact longer throughout their lives compared to the sedentary population. It doesn’t require a marathon, either: the amounts of aerobic exercise which imbue this protective effect can be a simple as a spirited morning hike or a long bike ride to the beach.

Finding Time to Turn Off

Although yet to be recognized as a behavioral addiction by the DSM-V (the most widely accepted manual for the diagnosis of mental disorders such as addiction), a wide consensus amongst scientists and clinical researchers already exists indicating that cell-phone addiction is a very real and prevalent problem.^[16] Indeed, cell-phones are everywhere and the age-of-entry for starting cell-phone use is progressively decreasing. In Spain, for instance, data from 2015 show that there was already more than 1 phone per person throughout the country. This, coupled with the fact that 70% of their population have personal devices by the age of 12 (and 83% by the age of 14)^[17], makes the devices nearly inescapable in modern life. In the United States, a study published in 2015 found that 63% of American university students qualified as having a diagnosable cell-phone addiction.^[16] This type of addictive behavior dysregulates the brain’s reward system and can leave a lasting imprint on important behavioral and emotional domains such as reward anticipation, value judgments, and rational decision making by altering functions of dopamine, the neurotransmitter which regulates most of these behaviors in the brain.

Dependence on cell-phones is strongly correlated with feelings of loneliness,^[18] poor sleep quality^[19] and chronic stress.^[20] These latter two, in particular, are known to induce chronic inflammation in the brain that increases the rate of neurodegeneration and decreases cognitive function, causing problems like chronic anxiety, depression, and even contribute to the etiology of dementia.^[21]

Vacation Impacts the Genomics of Disease and Inflammation

Interested in finding concrete markers of health and well-being following the restful period of vacation, researchers recently designed a study to measure the genomic alterations that follow a brief (6 day) vacation in healthy volunteers.^[22] By randomly assigning the volunteer women to spend either 6 days meditating at a retreat or to simply spend those 6 days relaxing, the researchers were able to identify biomarkers association with this ‘vacation effect.’ Unsurprisingly, psychological measures of stress and depression were significantly decreased in both groups across the test period, as well as more than one month later.

More surprisingly, however, the researchers found significant changes in a number of important biomarkers of long-term brain health following vacation (many of which were even more significantly altered in those who meditated during this period, as well). In fact, levels of the infamous Aß peptide (high levels of which are associated with depression,^[23] dementia^[24] and an increased risk of Alzheimer’s Disease) were found to be decreased following the retreat. The researchers also pointed to significant changes in markers of inflammation, indicating another benefit to both short- and long-term brain health as a result of a brief vacation

Conclusions

Vacations, both short and long, imbue a myriad of positive impacts on the health and well-being of our brains. Increased vitamin D from sun exposure and exercise enhances positive moods, increases our ability to learn and problem solve, and may stave off the long-term development of cognitive decline through dementia and other degenerative disorders. This is further compounded by the potential for vacation-induced reductions in biomarkers like Aß, which is associated with chronic depression, Alzheimer’s disease and dementia. Couple this with reduced inflammation from the pause in chronic stress caused by cell-phone addiction and you have a recipe for a major brain-boost. Moreover, these healthy habits can be ingrained during the break period, meaning that the beneficial behaviors don’t have to end with the return to work in the fall. So, spend the time this summer to unplug, unwind and take a sunshine-filled vacation break: your brain will thank you.

References

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