Our internal "body clock." Located in the Suprachiasmatic Nucleus (SCN) of the hypothalamus, it operates on a roughly 24-hour cycle. Light detection via the retina entrains the SCN to the day/night cycle, regulating the release of Melatonin from the pineal gland to induce sleepiness at night.
A typical night consists of 4-6 sleep cycles, lasting 90-120 minutes each. Awake → N1 → N2 → N3 → N2 → REM. Early Night: Dominated by N3 (slow-wave sleep). Late Night: Dominated by REM sleep. 5. Summary/Key Takeaways for PPT eeg and sleep physiology ppt
EEG and PSG are vital for distinguishing between conditions that look similar clinically but have different pathological roots. Our internal "body clock
Sleep is a complex physiological process that involves multiple stages, each with distinct characteristics. There are two main types of sleep: non-rapid eye movement (NREM) sleep and rapid eye movement (REM) sleep. NREM sleep is further divided into three stages: N1, N2, and N3. Awake → N1 → N2 → N3 → N2 → REM
: The most common stage; features sleep spindles and K-complexes .
: A deep dive into the neurophysiological mechanisms, including thalamocortical oscillations and homeostatic sleep regulation models like the "two-process model".