Eeg And Sleep Physiology Ppt -
Dominated by alpha rhythm (8–12 Hz) in the occipital channels when eyes are closed. If eyes are open, the EEG shows low-voltage, mixed-frequency beta activity (13–30 Hz).
Attenuation of alpha rhythm (loss of alpha waves) replaced by low-amplitude, mixed-frequency theta activity. Vertex sharp waves may appear toward the end of this stage. Non-REM Stage 2 (N2): True Sleep
To create a high-quality presentation on EEG and sleep physiology, incorporate interactive and visual components into your slide design: eeg and sleep physiology ppt
Rapid eye movement (REM) sleep is a unique stage characterized by a highly active brain—with EEG patterns very similar to wakefulness—coupled with skeletal muscle atonia (paralysis). This paradoxical stage is where most vivid dreaming occurs and is crucial for emotional regulation and memory processing. The "sawtooth waves" are specific sharp waves sometimes seen just before or during bursts of REM sleep.
To initiate sleep, the wake-promoting circuits must be inhibited. Dominated by alpha rhythm (8–12 Hz) in the
Sharp, high-voltage negative deflections followed by a slower positive component, lasting at least 0.5 seconds. They protect sleep by suppressing cortical arousal to non-threatening environmental noises. Non-REM Stage 3 (N3): Deep / Slow-Wave Sleep (SWS)
Stage N3, also known as Delta sleep or Slow-Wave Sleep (SWS), is the most restorative period. It constitutes 15–25% of total sleep time and is highly concentrated in the first third of the night. Vertex sharp waves may appear toward the end of this stage
Sleep is not a passive state of inactivity but a highly dynamic neurological process. EEG allows clinicians and researchers to: Diffentiate between wakefulness and sleep. Identify specific sleep stages. Detect micro-arousals and sleep fragmentation.
Polysomnography is the comprehensive recording of biophysiological changes during sleep. While PSG includes vectors like eye movements (EOG) and muscle tone (EMG), the EEG channel is the only tool that can directly identify sleep stages and micro-arousals. Slide 2: The International 10-20 Electrode Placement System
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:
Characterized by the loss of normal muscle atonia during REM sleep. Patients physically act out their dreams. The EEG shows normal REM features, but the EMG channel demonstrates sustained or intermittent muscle activity.
