This Saturday marks my 23rd week in Paris. As I get more acquainted with and orientated in this beautiful city full of history and modernity, I feel increasingly happy with my decision to study abroad here.Delving fully into the language and culture, I’ve had the opportunity to see the polar opposite sides of a resident filled Paris in January to the overwhelming influx of tourists starting early April. Despite the heat of an underground metro without air-conditioning and the invasion of foreigners in a city I now claim as my own, I find myself more in love and happier with my Parisian experience every day as I near my final weeks here.
Lately, I’ve noticed the city stays light long past dinnertime so I take the scenic route home while I usually head straight back to my room to start my work. However, am I really succumbing to the City of Love . . . or is the lingering sun really the cause of my increased feelings of happiness and simultaneous difficulty in focusing on my work? At a latitude of 48.8457°N, Paris currently experiences days that last over 16 hours (Sun and Moon, 2015). Due to such a northern latitude, we get 2 more hours of daylight to explore the city here in Paris than the 14-hour days Emory University receives in Atlanta, GA.
Light on Happiness
The circadian rhythm follows a 24-hour clock that changes our biological, mental, and behavioral processes in response to light and dark (Jackson, 2014). Light, a main natural cue we receive from our environment, regulates these rhythms and is affected by changes in daylight from one season to the next. While little research has been published showing that sunlight will actually make you happier, many studies have been conducted on the topic of light significantly easing depression. A current study aims to artificially mimic the effects of daylight through the use of light therapy for clinically depressed patients suffering from seasonal affective disorder (SAD), where symptoms of depression manifest particularly during winter months when there is a marked decrease in available sunlight (Reeves et al., 2012). Participants received 1 hour of bright light therapy and 1 hour of placebo (a dim red light used as a phony treatment and expected to have no clinical affect) in a randomized order. Using two different self-reporting depression scales, the Profile of Mood States-Depression-Dejection subscale and the Beck Depression Inventory II, Reeves et al. measured patients’ depressed mood before the start of the experiment, after hour 1 of treatment, and after hour 2 of treatment. Researchers found a statistically significant decrease in self-rated depression scores after treatment from before starting the light therapy. Multiple neurotransmitters, molecular compounds that neurons release in order to communicate with other neurons, are responsible for this rapid mood change. Upon light therapy stimulation, serotonin (a main neurotransmitter responsible for mood balance and involved in seasonal depression) was found to rise at a rate directly correlated to the amount of light administered (Reeves et al., 2012). Our long summer days in Paris allow for natural sessions of light therapy, which in turn leads to happier people.
Light on Attention
So now that I know why I feel happier, I also wondered if these lengthened spring nights in Paris could be having a reverse effect on my ability to concentrate on tasks rather than blaming my lack of motivation on an increasing infatuation with the “City of Love.” As we approach the longest day of the year during the summer solstice on June 21st, the day will be 7 hours and 56 minutes longer than it was when I arrived in the middle of winter (Sun and Moon, 2015). Not only am I staying outdoors longer, I’m going to bed 2-3 hours later than during the spring semester, while still waking up at the same hour as I did in winter. As the days lengthen and we stay more active, the potential for sleep deprivation and associated negative impacts on the brain’s ability to perform increase. Further, certain individuals can be more vulnerable to sleep deprivation, amplifying the resulting impact on performance and sleepiness (Chua et al., 2014). So, as we approach June 21st, I am reminded of the erratic behavior of the young lovers and comedic actors I saw in Shakespeare’s Midsummer Night’s Dream at La Comédie Française this April. Perhaps it wasn’t the meddlesome fairies after all, but rather neuroscience that would suggest they were vulnerable to sleep deprivation caused by the long summer day!
~ Amy Yeh
Chua EC-P, Yeo S-C, Lee IT-G, Tan L-C, Lau P, Cai S, Zhang X, Puvanendran K, Gooley J (2014) Sustained Attention Performance during Sleep Deprivation Associates with Instability in Behavior and Physiologic Measures at Baseline. Sleep 37(1): 27-39.
Jackson C, Capozzi M, Dai H, McMahon DG (2014) Circadian Perinatal Photoperiod Has Enduring Effects on Retinal Dopamine and Visual Function. The Journal of Neuroscience 34(13): 4627-4633.
Reeves G, Nijjar GV, Langenberg P, Johnson MA, Khabazghazvini B, Sleemi A, Vaswani D, Lapidus M, Manalai P, Tariq M, Acharya M, Cabassa J, Snitker S, Postolache TT (2012) Improvement in Depression Scores After 1 Hour of Light Therapy Treatment in Patients With Seasonal Affective Disorder. Journal of Nervous & Mental Disease 200 (1): 51–55.
Sun and Moon. (2015, May 1). In Time and Date. Retrieved from http://www.timeanddate.com/astronomy/france/paris