LU5

• Consciousness


  Knowing or being aware of ongoing experience occurring internally and around us
• Unconsciousness


  The state of being unaware of what is happening within and around us
• Conscious


  Can refer to a state of awareness (alert vs drowsy) or what is happening currently
• Self-awareness


  A special type of consciousness that occurs when we focus on ourselves as individuals
• Consciousness


  1. Involves variations in our state of awareness

  2. Our awareness changes dramatically across cycles of sleep and wakefulness

  3. All humans have 24 cycles of sleep and wakefulness
• Circadian rhythms


  Daily rhythms
• Circadian rhythms


  • Respond to a combination of internal and external factors
  • Internal biological clocks (hypothalamus) provide an approximate schedule for various processes
  • Internal biological clocks interact with external stimuli known as zeitgebers (time givers)
  • Light is one of the most important zeitgebers for humans
• In the absence of light

  Our internal clocks run a few minutes longer than a 24-hour cycle
• Eating patterns


  Are also significant zeitgebers
• Modern living and circadian rhythms

  • Our ancestors remained awake during daylight and slept throughout the dark of night
  • Technological advances, in particular the invention of artificial light, has shaped our contemporary sleep-wake patterns by making it easy to stay awake at night
  • Artificial light, including that produced by tablets and phones, affect sleep by breaking melatonin
• Changes in melatonin release have been implicated in a long list of human diseases, such as cancer and heart diseases (Common in people working at night)
• Hospitals and public safety jobs, involve work around the clock, which in turn is correlated with physical and psychological problems
• These people often present with maladaptive syndrome, characterized by personality, mood and interpersonal problems
• Accident rates in the industrial swing shift (3:00 p.m. – 11:30 p.m.) are higher than in the traditional day shift
• The graveyard shift (11:00 p.m.– 7:30 a.m.) is the most dangerous work period