<h2>Sedation</h2>

<p>This is a forced state of drowsiness or sleep and as indicated in your Ipnos link, it will not necessarily help with drowsiness or sleepiness brought about due to problems with your <a href="https://en.wikipedia.org/wiki/Circadian_rhythm" rel="noreferrer">circadian rhythm</a></p>

<p><a href="https://en.wikipedia.org/wiki/Sedation" rel="noreferrer">Sedation</a> is</p>

<blockquote>
  <p>the reduction of irritability or agitation by administration of sedative drugs, generally to facilitate a medical procedure or diagnostic procedure.</p>
</blockquote>

<h2>Drowsiness and Sleepiness</h2>

<p>The terms drowsiness, sleepiness and <a href="https://en.wikipedia.org/wiki/Hypnagogia" rel="noreferrer">hypnagogic period</a> are often used to describe the same thing in the general domain, but but in the scientific domain there are important neurophysiological and psychophysiological differences.</p>

<h2>Hypnagogic period</h2>

<p>This is the neurophysiological and psychophysiological transition period from the wake to sleep state.</p>

<h2>Drowsiness</h2>

<p>This is the state of the transition period from the wake to sleep state <strong>that can be objectively measured</strong>, for example, by EEG (please see <a href="https://doi.org/10.1037/10166-014" rel="noreferrer">Hori et al., 1994</a>)</p>

<p>Typical tests that describe the quality and quantity of the drowsyness are <a href="https://en.wikipedia.org/wiki/Multiple_Sleep_Latency_Test" rel="noreferrer">Multiple Sleep Latency Test (MSLT)</a> and Maintenance of Wakefulness Test (MWT) (<a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2424234" rel="noreferrer">Doghramji et al., 1997</a>).</p>

<h2>Sleepiness</h2>

<p>This is the <strong>subjective state of the subject/patient</strong>. It can also be qualified and quantified, but only by rating scales such as the <a href="https://web.stanford.edu/~dement/sss.html" rel="noreferrer">Stanford Sleepiness Scale (SSS)</a>, the <a href="http://www.britishsnoring.co.uk/sleep_apnoea/epworth_sleepiness_scale.php" rel="noreferrer">Epworth Sleepiness Scale (ESS)</a> (See also <a href="https://www.ncbi.nlm.nih.gov/m/pubmed/1798888" rel="noreferrer">Johns, (1991)</a>), the Karolinska Sleepiness Scale (<a href="https://www.ncbi.nlm.nih.gov/m/pubmed/2265922/" rel="noreferrer">Åkerstedt &amp; Gillberg, 1990</a>), etc.</p>

<h2>References</h2>

<p>Åkerstedt, T., &amp; Gillberg, M. (1990).  Subjective and objective sleepiness in the active individual, <em>The International Journal of Neuroscience</em>, 52(1-2): pp. 29–37)<br>
DOI: <a href="https://doi.org/10.3109/0020745900899424" rel="noreferrer">10.3109/0020745900899424</a> PMID: <a href="https://www.ncbi.nlm.nih.gov/m/pubmed/2265922/" rel="noreferrer">2265922</a></p>

<p>Doghramji, K., Mitler, M. M., Sangal, R. B., Shapiro, C., Taylor, S., Walsleben, J., Belisle, C. Erman, M. K., Hayduk, R., Hosn, R., O’Malley, E. B., Sangal, J. M., Schutte, S. L., &amp; Youakima, J. M. (1997). A normative study of the maintenance of wakefulness test (MWT), <em>Electroencephalography and clinical neurophysiology</em> 103(5): pp. 554–562.<br>
DOI: <a href="https://doi.org/10.1016/S0013-4694(97)00010-2" rel="noreferrer">10.1016/S0013-4694(97)00010-2</a> PMCID: <a href="https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2424234" rel="noreferrer">PMC2424234</a></p>

<p>Hori, T., Hayashi, M., &amp; Morikawa, T. (1994). Topographical EEG changes and the hypnagogic experience. In R. D. Ogilvie &amp; J. R. Harsh (Eds.), <em>Sleep onset: Normal and abnormal processes</em> (pp. 237-253).<br>
DOI: <a href="https://doi.org/10.1037/10166-014" rel="noreferrer">10.1037/10166-014</a></p>

<p>Johns, M. W. (1991). A new method for measuring daytime sleepiness: the Epworth sleepiness scale, <em>Sleep</em> 14(6): pp. 540-545<br>
DOI: <a href="https://doi.org/10.1093/sleep/14.6.540" rel="noreferrer">10.1093/sleep/14.6.540</a> PMID: <a href="https://www.ncbi.nlm.nih.gov/m/pubmed/1798888" rel="noreferrer">1798888</a></p>

CC BY-SA 3.0
2018-02-12T05:57:09.763Z
Thank you for your answer. It definitely helps explain the difference.
OhBeeHive
CC BY-SA 3.0
2018-01-29T10:59:48.280Z
2018-01-30T10:15:44.463Z
2018-01-30T10:15:44.463Z
Chris Rogers
<p>I have been trying to understand the difference between drowsiness/sedation and sleepiness. The only article I was able to find that partly answers my question is <a href="https://www.ipnos.com/blog/difference-sedation-sleep/" rel="nofollow noreferrer">"The difference between sedation and sleep" on ipnos.com</a>.</p>

<p>I have experienced both, and they feel distinctly different. Sleepiness feels like a drive, but drowsiness/sedation feels like a state. My personal experience has been that sleeping when drowsy/sedated does not relieve the drowsiness/sedation, but sleeping when sleepy resolves the sleepiness.</p>

<p>Back to the question: <strong>what is the neurological/neurobiological/psychopharmacological difference between sleepiness and drowsiness/sedation, and why does sleep resolve the one but not the other?</strong></p>

<sleep>
Difference between drowsiness/sedation and sleepiness
OhBeeHive
# Difference between drowsiness/sedation and sleepiness

(Asked by: username_0 on 2018-01-29)

I have been trying to understand the difference between drowsiness/sedation and sleepiness. The only article I was able to find that partly answers my question is ["The difference between sedation and sleep" on ipnos.com](https://www.ipnos.com/blog/difference-sedation-sleep/).

I have experienced both, and they feel distinctly different. Sleepiness feels like a drive, but drowsiness/sedation feels like a state. My personal experience has been that sleeping when drowsy/sedated does not relieve the drowsiness/sedation, but sleeping when sleepy resolves the sleepiness.

Back to the question: **what is the neurological/neurobiological/psychopharmacological difference between sleepiness and drowsiness/sedation, and why does sleep resolve the one but not the other?**

**Tags:** sleep


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## 1 answers

### Answer by username_1 on 2018-01-29. Score: 4 | Accepted answer

## Sedation

This is a forced state of drowsiness or sleep and as indicated in your Ipnos link, it will not necessarily help with drowsiness or sleepiness brought about due to problems with your [circadian rhythm](https://en.wikipedia.org/wiki/Circadian_rhythm)

[Sedation](https://en.wikipedia.org/wiki/Sedation) is

> the reduction of irritability or agitation by administration of sedative drugs, generally to facilitate a medical procedure or diagnostic procedure.

## Drowsiness and Sleepiness

The terms drowsiness, sleepiness and [hypnagogic period](https://en.wikipedia.org/wiki/Hypnagogia) are often used to describe the same thing in the general domain, but but in the scientific domain there are important neurophysiological and psychophysiological differences.

## Hypnagogic period

This is the neurophysiological and psychophysiological transition period from the wake to sleep state.

## Drowsiness

This is the state of the transition period from the wake to sleep state **that can be objectively measured**, for example, by EEG (please see [Hori et al., 1994](https://doi.org/10.1037/10166-014))

Typical tests that describe the quality and quantity of the drowsyness are [Multiple Sleep Latency Test (MSLT)](https://en.wikipedia.org/wiki/Multiple_Sleep_Latency_Test) and Maintenance of Wakefulness Test (MWT) ([Doghramji et al., 1997](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2424234)).

## Sleepiness

This is the **subjective state of the subject/patient**. It can also be qualified and quantified, but only by rating scales such as the [Stanford Sleepiness Scale (SSS)](https://web.stanford.edu/~dement/sss.html), the [Epworth Sleepiness Scale (ESS)](http://www.britishsnoring.co.uk/sleep_apnoea/epworth_sleepiness_scale.php) (See also [Johns, (1991)](https://www.ncbi.nlm.nih.gov/m/pubmed/1798888)), the Karolinska Sleepiness Scale ([Åkerstedt & Gillberg, 1990](https://www.ncbi.nlm.nih.gov/m/pubmed/2265922/)), etc.

## References

Åkerstedt, T., & Gillberg, M. (1990).  Subjective and objective sleepiness in the active individual, *The International Journal of Neuroscience*, 52(1-2): pp. 29–37)  
DOI: [10.3109/0020745900899424](https://doi.org/10.3109/0020745900899424) PMID: [2265922](https://www.ncbi.nlm.nih.gov/m/pubmed/2265922/)

Doghramji, K., Mitler, M. M., Sangal, R. B., Shapiro, C., Taylor, S., Walsleben, J., Belisle, C. Erman, M. K., Hayduk, R., Hosn, R., O’Malley, E. B., Sangal, J. M., Schutte, S. L., & Youakima, J. M. (1997). A normative study of the maintenance of wakefulness test (MWT), *Electroencephalography and clinical neurophysiology* 103(5): pp. 554–562.  
DOI: [10.1016/S0013-4694(97)00010-2](https://doi.org/10.1016/S0013-4694(97)00010-2) PMCID: [PMC2424234](https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2424234)

Hori, T., Hayashi, M., & Morikawa, T. (1994). Topographical EEG changes and the hypnagogic experience. In R. D. Ogilvie & J. R. Harsh (Eds.), *Sleep onset: Normal and abnormal processes* (pp. 237-253).  
DOI: [10.1037/10166-014](https://doi.org/10.1037/10166-014)

Johns, M. W. (1991). A new method for measuring daytime sleepiness: the Epworth sleepiness scale, *Sleep* 14(6): pp. 540-545  
DOI: [10.1093/sleep/14.6.540](https://doi.org/10.1093/sleep/14.6.540) PMID: [1798888](https://www.ncbi.nlm.nih.gov/m/pubmed/1798888)

> **Comments:**
> **username_0**: Thank you for your answer. It definitely helps explain the difference.  

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