sleep na ko

• Shifting the circadian rhythm to work at night and sleep during the day

  Can be achieved by having bright lights at night and darkness during the day
• Pineal gland


  A small gland located in the brain that produces melatonin and plays a role in regulating the sleep-wake cycle
• Genes controlling the circadian rhythm are similar in mammals and insects. Circadian rhythms result from a feedback cycle involving genes that produce proteins PER and TIM, which inhibit the genes that produce them
• Endogenous circannual rhythm


  Internally generated rhythms that last approximately one year, such as seasonal changes in behavior or physiology
• People's preference for staying awake late and sleeping late in the morning is influenced by their circadian rhythm, with the greatest preference occurring around the age of 20
• Jet lag


  A temporary sleep disorder that occurs when you travel across multiple time zones, causing your circadian rhythm to be out of sync with the new time zone
• Suprachiasmatic nucleus (SCN)


  A part of the hypothalamus in the brain that serves as the body's master clock, controlling circadian rhythms for sleep and temperature
• The biological clock continues to operate in constant light or darkness, but the timing of sunrise strongly influences the circadian rhythm
• The suprachiasmatic nucleus (SCN), located in the hypothalamus, generates the body's circadian rhythms for sleep and temperature
• The SCN controls the body's rhythm partly by regulating the release of melatonin by the pineal gland. Melatonin increases sleepiness and can reset the circadian rhythm when administered at certain times of the day
• Endogenous circadian rhythms

  Internally generated rhythms of activity and sleep lasting about 24 hours, even in an unchanging environment
• Zeitgeber


  External cues, such as light or temperature, that help regulate the body's circadian rhythm
• Melatonin


  A hormone produced by the pineal gland in the brain that regulates sleep-wake cycles. It is often used as a supplement to help with sleep disorders
• Light resets the biological clock

  Through a branch of the optic nerve that extends to the SCN. Special ganglion cells respond directly to light and contribute to this reset
• It is generally easier for most people to adjust to a cycle longer than 24 hours (traveling west) than a cycle shorter than 24 hours (traveling east)