Sleeping and Dreaming

Here’s another guide for those struggling with this topic! Hope it helps! :grinning:

Sleeping and Dreaming

As a high school student myself, I often either say or hear the phrase “I need more sleep” on a daily basis, but what is sleep? Sleep is the irresistible temptation to whom we inevitably succumb.

Why does sleep occur? :sleeping:

The need for sleep comes from your body’s circadian rhythms or the sleep cycle. (:alarm_clock:) Circadian rhythms occur on a 24-hour cycle and include sleep and wakefulness. It’s also called our “biological clock,” which allows it to be altered by artificial light. This is because light triggers the suprachiasmatic nucleus to decrease (morning) melatonin from the pineal gland and increase (evening) it at nightfall.

How is sleep measured? :bar_chart:

About every 90 minutes, we pass through a cycle of five distinct sleep stages. With each 90 minute cycle, stage 4 sleep decreases and the duration of REM sleep increases (more detail in the sections below). When someone closes their eyes but is awake, their brain activity slows down to a large amplitude and slow, regular alpha waves. This is why a meditating person exhibits an alpha brain activity.

Sleep Stages 1 & 2 :thought_balloon:

During early, light sleep (stages 1-2) the brain enters a high-amplitude, slow, regular wave form called theta waves (5-8 cps). A person who is daydreaming shows theta activity.

Sleep Stages 3 & 4 :zzz:

During deepest sleep (stages 3-4), brain activity slows down. There are large-amplitude, slow delta waves (1.5-4 cps) in this sleep stage.

Sleep Stage 5 :eyes:

This stage of sleep is REM sleep. A person during this sleep stage exhibits Rapid Eye Movements and reports vivid dreams. After reaching the deepest sleep stage (4), the sleep cycle starts moving back towards stage 1. Although still asleep, the brain engages in low-amplitude, fast and regular beta waves (15-40 cps) much like awake-aroused state.

What are the different theories of sleep?

  1. Sleep Protects. Sleeping in the darkness when predators loomed about kept our ancestors out of harm’s way. :boom:
  2. Sleep Helps Us Recover. Sleep helps restore and repair brain tissue. :+1:
  3. Sleep Helps Us Remember. Sleep restores and rebuilds our fading memories. :speech_balloon:
  4. Sleep May Play a Role in the Growth Process. During sleep, the pituitary gland releases growth hormone. Older people release less of this hormone and sleepless. :chart_with_upwards_trend:

What are some common sleep disorders?

  • Insomnia: A persistent inability to fall asleep. :flushed:

  • Narcolepsy: Overpowering urge to fall asleep that may occur while talking or standing up. :dizzy:

  • Sleep apnea: Failure to breathe when asleep. :triumph:

Children are most prone to:

  • Night terrors: The sudden arousal from sleep with intense fear accompanied by physiological reactions (e.g., rapid heart rate, perspiration) which occur during Stage 4 sleep. :sweat:

  • Sleepwalking: A Stage 4 disorder which is usually harmless and unrecalled the next day. :flushed:

  • Sleep talking: A condition that runs in families, like sleepwalking.:sleeping::speech_balloon:

Sleep is also often associated with dreaming, but why do we dream?

There are 5 main theories associated to dreaming:

  • Wish Fulfillment: Sigmund Freud suggested that dreams provide a psychic safety valve to discharge unacceptable feelings. The dream’s manifest (apparent) content may also have symbolic meanings (latent content) that signify our unacceptable feelings. :gift:

  • Information Processing: Dreams may help sift, sort, and fix a day’s experiences in our memories. :open_book:

  • Physiological Function: Dreams provide the sleeping brain with periodic stimulation to develop and preserve neural pathways. Neural networks of newborns are quickly developing; therefore, they need more sleep. :heartbeat:

  • Activation-Synthesis Theory: Suggests that the brain engages in a lot of random neural activity. Dreams make sense of this activity.:thought_balloon:

  • Cognitive Development: Some researchers argue that we dream as a part of brain maturation and cognitive development. :muscle:

So, now that you know more about the sleep cycle and theories of dreaming, maybe you can try to improve your sleeping habits! By the end of this article, you should finally know the ‘how’s and ‘why’s behind sleeping and dreaming!

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