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• What is the definition of consciousness?


  Consciousness refers to our awareness of internal and external stimuli.
• How can consciousness be described?


  Consciousness can be described as a continuum ranging from full awareness to deep sleep.
• What is wakefulness characterized by?


  Wakefulness is characterized by high levels of sensory awareness, thought, and behavior.
• What distinguishes sleep from wakeful rest?

  Sleep is marked by physical activity and reduced sensory awareness, distinct from wakeful rest.
• What are the states of consciousness related to wakefulness and sleep?


  • Daydreaming
  • Intoxication (alcohol/drugs)
  • Meditative states
  • Hypnotic states
  • Altered states from sleep deprivation
  • Drug-induced anesthesia
• How are biological processes related to consciousness?


  Many processes and behaviors associated with consciousness are biologically based.
• What role do biological rhythms play in consciousness?


  Biological rhythms, particularly circadian rhythms, regulate our states of consciousness.
• What is a biological rhythm?


  A biological rhythm is an internal cycle of biological activity, such as the menstrual cycle.
• What is the menstrual cycle?


  The menstrual cycle is a recurring 28-day pattern of bodily changes.
• What is a circadian rhythm?


  A circadian rhythm is a type of biological rhythm that takes place over a 24-hour period.
• How does the circadian rhythm influence consciousness?


  Circadian rhythms influence changes in our state of consciousness, such as sleep and wakefulness.
• What is the biological clock and where is it located?


  The biological clock is located in the hypothalamus and is responsible for homeostasis.
• What is the role of the suprachiasmatic nucleus (SCN)?


  The SCN is the brain's clock mechanism that synchronizes the internal clock with the external world.
• How does melatonin affect sleep-wake cycles?


  Melatonin helps regulate sleep-wake cycles and is stimulated by darkness.
• What is chronotype?


  Chronotype refers to individual differences in circadian patterns of activity.
• What is jet lag and what causes it?


  Jet lag occurs when traveling across multiple time zones, causing a mismatch between internal circadian cycles and the new environment.
• What are the symptoms of jet lag?


  Symptoms of jet lag include fatigue, sluggishness, irritability, and insomnia.
• How does rotating shift work affect circadian rhythms?


  Rotating shift work disrupts normal circadian rhythms, leading to sleep problems and increased risk of depression.
• What strategies can alleviate disruptions in circadian rhythms?


  Bright light exposure during work shifts and limiting light exposure when off work can help realign the biological clock.
• What is sleep debt?


  Sleep debt is the accumulated lack of sufficient sleep over time.
• What are the consequences of sleep debt?


  Consequences of sleep debt include reduced alertness and mental efficiency.
• How has modern life affected sleep duration?

  Since the advent of electric light, many people sleep less than the recommended 7–8 hours a night.
• What psychological effects are associated with sleep deprivation?


  Sleep deprivation can lead to decreased mental alertness and cognitive function.
• What physiological effects are associated with sleep deprivation?


  Physiological effects include obesity, increased blood pressure, and reduced immune function.
• How does sleep deprivation affect cognitive and motor function?


  Sleep deprivation can impair cognitive and motor skills as significantly as alcohol intoxication.
• What is the average amount of sleep by age 65 according to meta-analysis?


  By age 65, we average fewer than 7 hours of sleep per day.
• How much of our lives do we spend sleeping?

  We spend about one-third of our lives sleeping, approximately 25 years.
• What is the significance of sleep for non-sleeping animals?


  Some species, like certain fish and amphibians, never sleep, while dolphins can go long periods without sleep.
• What is sleep rebound?


  Sleep rebound is when individuals fall asleep more quickly after sleep deprivation, indicating the body's need to recover lost sleep.
• How is sleep characterized in terms of brain activity?

  Sleep is characterized by distinct patterns of brain activity observable through electroencephalography (EEG).
• What brain regions are involved in sleep-wake cycles?

  The thalamus and hypothalamus regulate slow-wave sleep, while the pons regulates REM sleep.
• What hormones are associated with sleep?

  Melatonin, follicle stimulating hormone (FSH), luteinizing hormone (LH), and growth hormone are associated with sleep.
• What are the proposed hypotheses for why we sleep?

  Hypotheses include restoring energy, avoiding predation risks, and varied evolutionary pressures.
• What cognitive functions are affected by sleep deprivation?


  Sleep deprivation can disrupt cognition, leading to memory deficits and impairing attention and decision-making.
• How does slow-wave sleep contribute to memory formation?


  Slow-wave sleep enhances performance and is essential for effective memory formation after learning.
• What cognitive benefits are linked to sleep?


  Sleep is linked to improved creative thinking, better language learning, and enhanced emotional processing.
• What are the stages of sleep?

  1. REM Sleep (Rapid Eye Movement)

  • Quick eye movements
  • Associated with vivid dreams
  • Crucial for memory consolidation

  1. NREM Sleep (Non-Rapid Eye Movement)

  • Divided into four stages:
  • Stage 1: Transition phase with alpha and theta waves
  • Stage 2: Deep relaxation with sleep spindles and K-complexes
  • Stages 3 and 4: Deep sleep with delta waves
• What characterizes REM sleep?


  REM sleep is marked by quick eye movements and brain waves resembling wakefulness.
• What is the significance of NREM sleep stages?


  NREM sleep stages are crucial for physical recovery, tissue repair, and memory consolidation.
• What happens during Stage 1 of NREM sleep?


  Stage 1 marks the transition from wakefulness to sleep, with a decrease in muscle tension and core body temperature.