Circadian Rhythm Sleep-Wake Disorders

To discuss the next sleep disorder, we first need to understand a new concept: circadian rhythm. Have you ever heard of it? What does it mean? Let me explain it in simple terms.

We all know the word rhythm we probably associate it with music:
"This song has a great rhythm."
Rhythm refers to something repetitive, something that occurs in a consistent pattern over time.

But what about circadian? If we replace the word circadian with daily, we retain the same meaning.

So, the circadian rhythm is a biological cycle that occurs repeatedly within a 24-hour period. Many processes in our body follow this rhythm, including:

• The release of certain hormones
• Fluctuations in body temperature
• The sleep-wake cycle

You may have heard the term biological clock before. The idea is that our body has an internal regulatory system.
For example, when we go to sleep, we usually turn off the lights.

• Absence of light → Melatonin is released → Sleep state
• Presence of light → No melatonin release → Wakefulness

This self-regulation system helps maintain a healthy sleep-wake cycle.

If this system fails to function properly, it can lead to circadian rhythm sleep-wake disorders.

According to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), Circadian Rhythm Sleep-Wake Disorders are characterized by:

• Disruption of the circadian rhythm leading to persistent sleep disturbances
• Excessive sleepiness and/or insomnia
• Significant clinical distress

Sources

• American Psychiatric Association (2013) - Diagnostic and Statistical Manual of Mental Disorders (5th ed.).
• Bernhill, J. W. (2014) - DSM-5 Clinical Cases.

I also recommend watching this: YouTube Video.

If you'd like me to explain another psychology topic in my own words, feel free to ask in the comments!