A study by Dr Thomas Wehr, a psychiatrist, artificially altered timings of darkness for participants to observe changes in sleeping pattern. This change of light was to mirror a ‘prehistoric night’ whereby the participants were deprived of any form of artificial light for 14 hours each ‘cycle’. The study found that a routine was appearing in the participants: after resting awake in bed for around 2 hours, they fell asleep. There were two ‘phases’ of sleep which were around 4 hours each with a couple of hours waking time between them. During the time awake, the hormones of the participants were significantly different to hormones that are usually found when you’re awake. One of the hormones elevated was prolactin, which is usually produced at high levels during breast-feeding. Prolactin has been linked to a reduced metabolic rate, stimulation of the immune system and stress reduction. This was perhaps reflected in the participants emotions as they reported that they felt reflective and calm during these periods of awakeness. This study demonstrated how seasonal changes in sun exposure could impact us and our sleeping patterns. With the early sunsets, it really does make the rest of the day significantly harder. I for one find these reduced daylight hours make me feel much more tired despite artificial light exposure. However, does this seasonal alteration in behaviour really relate to traditional hibernation?
Hibernation is a seasonal state for some animals where the metabolic, heart and breathing rate, as well as body temperature, is reduced. Traditionally, hibernation is linked to long periods of ‘deep hibernation’ that can last for many months, but during this time there are short periods of increased metabolic activity restoring heart and breathing rates. Although the reason for this is unknown, it could be linked to immune system boosting. These periods of alteration in metabolic activity during hibernation could be synonymous to these short periods of time awake observed in the Wehr study. Although these changes in our sleeping patterns may not be classically defined as hibernation, these changes may have a positive and restorative effect on our physical and mental health like hibernation.
Our commitments and deadlines unfortunately do not conform to the same decreasing activity levels during the winter months, making things particularly challenging at times. I personally have found that when the weather is particularly miserable, and getting to the library is not the most appealing prospect, having a good bright LED lamp at home can really make a difference in my focus and doesn't cost a lot of money. On the bright side, the clocks will soon go forward and the days will be longer and hopefully warmer making everything just a little bit easier.