A hypnogram is a graph that plots time on the x-axis and sleep stages on the y-axis, providing a macro-level view of a night's sleep architecture.
High muscle tone; frequent blinking and voluntary eye movements. Non-REM Stage 1 (N1): Light Sleep
To study sleep objectively, clinicians use Polysomnography (PSG), a multi-parametric test that records various body functions during sleep. A standard PSG presentation slide should highlight these three essential biopotentials:
Alpha waves drop below 50% of the epoch. They are replaced by low-amplitude, mixed-frequency theta waves (4–7 Hz). Vertex sharp waves may appear at the end of the stage. EOG: Slow, rolling eye movements. EMG: Muscle tone begins to decrease. Stage N2 (Stable NREM Sleep) eeg and sleep physiology ppt
: Explain that EEG (brain waves) is used alongside EOG (eye movements) and EMG (muscle tone) to classify sleep stages. 2. The 5 Stages of Sleep
Placed on the chin to monitor muscle atonia, a defining feature of REM sleep. 2. Neurobiology of the Sleep-Wake Cycle
To effectively present the physiology, a comparison table is highly effective for your PPT: A hypnogram is a graph that plots time
Brief bursts of 11–16 Hz activity lasting at least 0.5 seconds, generated by the thalamus.
A healthy night of sleep consists of 4 to 6 cycles, each lasting roughly 90 to 120 minutes. These cycles shift between Non-Rapid Eye Movement (NREM) and Rapid Eye Movement (REM) sleep. A is the graph that charts these cyclic transitions across the night. Early Night: Dominated by deep, slow-wave NREM sleep. Late Night: Dominated by longer, more intense REM episodes. 4. EEG Stages of Sleep (AASM Criteria)
: An Electroencephalogram (EEG) records electrical activity in the brain via electrodes on the scalp. A standard PSG presentation slide should highlight these
Triple trace highlighting low-voltage EEG, rapid eye movements, and flat chin EMG.
This comprehensive guide breaks down the core concepts of EEG and sleep physiology into clear, presentation-ready modules. 1. Introduction to EEG in Sleep Medicine