Insomnia - Hypersomnolence

The first sleep-wake disorder we’ll discuss is the most common one, which you’ve likely heard of: insomnia. A situation that is more or less the opposite of insomnia (but equally potentially debilitating) is hypersomnolence. Let’s explore these disorders more closely in my own words.

The word insomnia, like many other terms we encounter, is formed by a prefix, “in-,” and the root “sonnia.” Let’s take a simple example to explain the meaning of “in-”: efficient vs. inefficient. As you can see, the prefix “in-” gives a negative connotation to the word. Similarly, insomnia can be summarized as a poor quantity and quality of sleep that leads to significant consequences in the individual’s life.

According to the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), insomnia is characterized by:

• One or more of the following symptoms:
  • Difficulty initiating sleep (prolonged sleep latency)
  • Difficulty maintaining sleep (frequent awakenings with trouble falling back asleep)
  • Early morning awakening (with an inability to return to sleep)
• The symptoms cause significant distress
• The symptoms occur at least 3 times per week for a duration longer than 3 months
• The symptoms cannot be better explained by another condition.

If you’ve ever experienced a sleepless night, you’re familiar with the main consequences of this disorder. The first and most intuitive one is daytime sleepiness, followed by difficulty paying attention and problems with concentration. Feeling irritable is also common. Another emotional symptom is lability, or an increased tendency to become emotional or cry easily.

Let’s move on to hypersomnolence. This word, like insomnia, contains a prefix, “hyper,” which means “too much.” Hypersomnolence, therefore, refers to a condition where one feels sleepy during the day despite having slept a sufficient number of hours.

According to the DSM-5, hypersomnolence is characterized by:

• Despite obtaining at least 7 hours of sleep, one or more of the following symptoms occur:
  • Falling asleep during the day
  • A main sleep period lasting 9 or more hours that does not feel restorative
  • Difficulty becoming fully awake after an abrupt awakening
• The symptoms occur at least 3 times per week for a duration longer than 3 months
• The symptoms cause significant distress
• The symptoms cannot be better explained by another condition.

An interesting term to remember in relation to hypersomnolence is “sleep inertia,” which refers to that groggy, foggy feeling experienced upon waking up—a common symptom in this disorder.

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: video.

If you’d like me to describe another psychology topic in my own words, let me know in the comments!