Circadian rhythms, the pineal gland and melatonin
-By Timothy Lyons
Circadian rhythms, the pineal gland and melatonin are all involved in the sleep wake cycles. Circadian rhythms are the bodies daily rhythm cycles that respond to light cues from the surrounding atmosphere. These rhythms are both passive responses and active internal mechanisms designed to put the body into natural sleep and wake cycles these cycles correspond to the shift between night and day. It is the body’s reaction of winding down during low light times and revving up during daylight.
One of the brain structures involved in this sleep process is the pineal gland. This is a small area in the midbrain that secretes melatonin during nighttime hours. Melatonin is a neurochemical that helps the body react to seasonal changes in light. As the amount of nighttime increases during winter months, the pineal gland secretes more melatonin. The secretion of melatonin helps people to adjust to changes in seasons but can also help in the adjustment of time zone changes, night work shifts and assists blind persons that do not have the ability to differentiate lighting change (Carson & Birkett, 2017; Price, 2011).
Circadian rhythms and night shift changes
Because the body naturally responds to changes in light changes, there can be implications to people who work night shifts. From (Price, 2011) we can see that not only are these rhythms difficult to change but that there is a positive correlation between working nights, higher incidence of sleep disorders, fatigue and even a greater risk of heart disease. In addition to these problems there was also an increased risk of driving accidents and near miss driving problems when persons had worked the night shift and then drove home.
There are some other problems that have been identified with rhythms and fatigue. When people work night shifts they become more tired. This makes moods worse. It also affects cognitive function. Another result is that reflexes are slowed. A person’s ability to defend against disease is decreased. A fatigued person’s perspective can be altered so that they become irritable and this increases the likelihood of negative interactions with coworkers (Price, 2011).
References for circadian rhythms, the pineal gland and melatonin
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