6. Sleep & Dreams

Circadian rhythm

The body’s internal clock.

Steps of the Sleep cycle

1. Light drowsiness

2. Sleep spindles

3. Deep sleep

4. Deep sleep (exit stage)

5. Lighter sleep & dreams

Reasons why we dream

• Activation Synthesis Model

• Memory consolidation

Activation Synthesis Model

Dreams are the brain's attempt to make sense of random neural activity during sleep

Memory consolidation

Dreams are the brain’s attempt to make sense of the day.

Sleep disorders

• Insomnia

• Sleep apnea

• Sleep paralysis

• Somnambulism

• Sleep behavior disorder

• Narcolepsy

• Night terrors

Insomnia

Inability to sleep.

Sleep apnea

Breathing issues while asleep.

Sleep paralysis

Inability to move while asleep (and upon waking up).

Somnambulism

Walking while asleep.

Sleep behavior disorder

Talking or moving while asleep.

Narcolepsy

Excessive sleepiness.

Night terrors

Waking up in extreme fear.

Why do we sleep?

To replenish energy after expending it throughout the day.