Sleep disorders are an important part of neurology examinations as they require a strong knowledge of complex diagnostic studies such as EEG, and also of a multitude of medications. In this chapter, you will learn sleep waveforms using real EEG tracings, and review high-yield treatments for sleep disorders. Test your knowledge at the end with practice questions and flashcards!

Authors: Jody Manners MD, Brian Hanrahan MD

Chapter Multimedia Content

Table of Contents

Table of Contents

Phases of Sleep

Wakefulness

  • Characterized by alpha frequency activities, sporadic eye movements, and a posteriorly dominant alpha rhythm that attenuates with eye-opening.

NREM sleep

  • Stage N1 (5%): Attenuation of the alpha rhythm, the emergence of theta activity, and slow rolling eye movements.
    • Frontocentral beta activity can increase.
    • Vertex waves and small sharp spikes can be seen.
    • Young adults spend the least amount of time in NREM stage 1 sleep.
  • Stage N2 (45-55%):
    • The stage at which adults spend the most time during normal sleep.
    • Characterized by the presence of either sleep spindles and/or K-complexes with theta range background activity.
    • Positive Occipital Sharp Transients of Sleep (POSTS) are most prevalent in N2 but can also occur rarely in N1 and N3 sleep.
    • Sleep spindles are thought to be generated by the reticular thalamic nucleus.
  • Stage N3 (15-20%):
    • a.k.a “deep sleep” or “slow-wave sleep” (no longer called “stage 4 sleep”)
    • EEG will show slow-waves and high amplitude delta waves.
    • Parasomnias tend to occur during this stage.
    • Interictal EEGs can show anterior temporal spikes especially if the EEG is performed during non-rapid eye movement (NREM) sleep.

REM sleep

  • 20-25% of sleep.
  • Normally occurs ~90 minutes into sleep.
  • Characterized by a desynchronized low voltage, high-frequency background.
  • There will be decreased EMG activity (REM atonia).
  • Sharply peaked irregular eye movements with lateral rectus spikes (see below) can be seen. Note the lack of muscle artifact.


 

Log in to View the Remaining 60-90% of Page Content!

 
 

New Subscriber? Use this form!

(Or, Click Here to learn about our institution/group pricing)
  • Full access to all site content, including responsive customer service, 600+ question bank, 35 text chapters, 50 EMG cases, 500+ diagnostic images, 100+ EEGs, and 700+ flashcards!
    Full access to all site content, including responsive customer service, 600+ question bank, 35 text chapters, 50 EMG cases, 500+ diagnostic images, 100+ EEGs, and 700+ flashcards!
    Full access to all site content, including responsive customer service, 600+ question bank, 35 text chapters, 50 EMG cases, 500+ diagnostic images, 100+ EEGs, and 700+ flashcards!
    You have selected a Group Membership. After a successful payment you will be able to invite up to %s additional members.
    Applying discount code. Please wait...
  • Credit / Debit Card Information

Table of Contents

Table of Contents