Many people hate it
when they are trying to sleep and someone turns on the light. Science reveals
that maybe turning on the light at night while some one sleeping can harm their
sleeping cycle. According to Ronda Kaysen’s article “Light Bulbs that Help you
Sleep”,” Stare at a bright, bluish light — like the one from your
smartphone, tablet or television — and your body sends a signal to your brain
to stop producing melatonin, a powerful hormone that helps you fall asleep” Now one may wonder what is a circadian clock and what
does that have to do with my sleep. Dr. Charles A Czeisler states this problem
should not be gone unnoticed. Dr.
Michael J. Breus, a clinical psychologist and a fellow at the American
Academy of Sleep Medicine, states, “People
are exposing themselves to light and it’s having a cascading effect on their
health on multiple levels”. Weight
loss, libido, mood and sleep patterns are impacted by disruptions on our
circadian clock. Chronic sleep deprivation caused by these disruptions can
increase the risk of cardiovascular disease.
The circadian clock
is disrupted when light is exposed during the nighttime. According to Dr.
Daniel Cavanaugh, at the Loyola University of Chicago, sleep in controlled by
homeostatic and circadian processes. Mutations in the circadian processes can
cause one to sleep for abnormal amounts of sleep, or can cause deprivation of
sleep depending on the mutation. In his article, “The Drosophila
Circadian Clock Gates Sleep through Time-of-Day Dependent Modulation of
Sleep-Promoting Neurons”, Cavanaugh mentions, “It
has been proposed that the lLNvs are involved in light-induced arousal,6 and that
gamma-aminobutyric acid (GABA)-ergic inhibition of lLNvs controls sleep latency
and sleep maintenance at night” In his study he wants to determine how
different times of day can be impacted by the activation of these neurons. To
determine this, flies were loaded into glass tubes that contained sucrose, agar
and their locomotor activity was determined by Drosophila Activity
Monitoring system (DAMS) and Sleep analysis was performed with PySolo software.
There were two types of flies, ones who had dTRPA1, which is a neuronal
activator and Shibire, an inhibitor. Sleep is assessed before and after
temperature moderations that cause activation of inhibition of the neurons.
Manipulation of darkness and light was performed to compare the circadian
clocks of the mutated flies to the control flies.
There were 2 experiment conditions:
light-dark and constant darkness. Flies were exposed to light for 12 hours and
darkness for 12 hours and their body temperature was shifted throughout this
experiment and in the constant darkness, for three days they received 12 hours
dark an light and then after 3 days it was a constant darkness for 2 days. This
experiment used Arousal Threshold Assays, Negative Geotaxis Assay, Immunohistochemistry,
and Location Heat Maps to determine the
effects of light and temperature on the circadian clock and the activation
neurons. This experiment stated that sleep changes were
time-of-day dependent. Activation of sleep-promoting neurons were effective
during the middle of the day and night, and ineffective during the day-to-night
and night-to-day transitions. However, time-of- day specific effects were
absent in flies that lacked functional circadian clocks. This means that light
exposure can cause your clock to be set back or set forth causing one to sleep
more or less, which can interrupt your regular body functions.
Dr. Cavanaugh’s lecture helps explain how light can
impact the neurons that are activated. The activation of these neurons causes
one either to sleep or to keep awake. In Kaysen’s article, the importance of
light exposure is discussed. This article talks about how light can cause one
to face problems with their homeostatic and circadian processes. Dr.
Cavanaugh’s experiment helps one understand which neurons when activated can
cause one to sleep and which neurons are inhibitors of sleep. His experiment
also lets the readers know that other homeostatic changes can be caused by
sleep, like temperature. Dr. Cavanaugh’s manipulation of homeostatic variables
such as temperature, and neuron activation helps one understand the importance
of light exposure on the body. Dr. Cavanaugh’s discussion of the circadian
clock and how it is preset according to the time of day also helps one
understand how darkness and light impact the clock itself to know when to sleep
and when to stay awake. Light is a factor that can manipulate the clock and
manipulation of this clock can cause a disruption to the sleep cycle.
However, with advancing technology and
scientific research, some light bulbs are made to help you sleep better at
night. For example, Sleepy Baby bulb, its light does not interfere with
melatonin production, so your clock is not disrupted. An individual can have a
good night sleep, if they can adjust their sleep to the dimness and light color
exposure in their room with these bulbs. Time of day has an impact on sleep,
but so does light exposure. In order to maintain a good night sleep, both
things are to keep in mind, light exposure and time of day.
References:
Light Image:
http://earth911.com/wp-content/uploads/2015/03/ilumi-smartbulb-color-range.jpg
Cavanaugh, Daniel J.,
Abigail S. Vigderman, Terry Dead, David S. Garbe, and Amita Sehgal. “The
Drosophila Circadian Clock Gates Sleep through Time-of Day Dependent Modulation
of Sleep- Promoting Neurons.” Sleep 39.2 (2016): 345-56. Web. 24 Feb.2017.
No comments:
Post a Comment