Sleep Stages and REM Sleep

• Study guide on sleep, altered states, drugs, senses, and perception.

All About Sleep

• Sleep stages include Stage 1, Stage 2, Stage 3 and 4, and Stage 5.
• Stage 1 is a very light, Non-Rapid Eye Movement (NREM) sleep stage that lasts 5-15 minutes and is associated with the common feeling of falling.
• Stage 2 is a light, NREM sleep stage lasting 5-15 minutes where body temperature drops and heart rate slows.
• Stage 3 & 4 are slow wave/delta, NREM sleep stages each lasting 5-15 minutes. Stage 4 is slightly deeper and is involved in body self-repair.
• Stage 5 is the REM sleep stage, with brain activity that is similar to waking levels, taking 10 minutes in the first cycle and up to one hour in subsequent cycles.
• REM sleep occurs after the sleep cycle restarts, and is the stage where dreaming occurs.

REM Sleep

• Heart rate increases and becomes irregular.
• Blood pressure rises.
• Breathing increases.
• Eyes move back and forth rapidly.
• It makes up 20% of total sleeping time.
• Major muscles become paralyzed.
• Dreams are lengthier and more detailed.
• REM sleep plays a role in learning, memory, storing information, and emotional experiences.

Why We Sleep

• Resting restores and replenishes the brain and body.
• Repairing neurons and resting neurotransmitters is part of sleeping.
• Physical growth and development is supported, involving some hormones that are only secreted during sleep.

Dream Theories

• Unconscious Wish Fulfillment (Freud): Dreams represent what the unconscious mind wants the conscious mind to do.
• Dream for Survival Theory: Important information needed for survival is reconsidered and reprocessed.
• Activation Synthesis Theory: Random memories activate and become connected to make a narrative.

Sleep Hygiene

• Sleep in a cool temperature, around 18°C.
• Maintain regularity by having the same bed and wake-up times, even on weekends.
• Sleep the amount recommended for your age.
• Cleanliness: Wash sheets once every week.
• Avoid meals, especially caffeine and sugar.
• Taking a warm bath 60-90 minutes before sleeping helps to improve sleep.
• Daily 30 minutes of physical activity improves sleep.
• Only use the bed for sleep because of brain association.

Sleep Disorders

• Narcolepsy is a sleep disorder that deregulates a person's sleep-wake cycles, causing a variety of effects.
• Irregular sleep and extreme sleepiness throughout the day causes "sleep attacks".

Narcolepsy Symptoms

• Being extremely tired during the day is a symptom.
• Strong emotions cause involuntary movement, muscle weakness or slurred speech (cataplexy).
• Sleep paralysis and hallucinations close to sleep time are symptoms.
• Continuing to do tasks that were being done before a sleep attack (automatic functions) occurs.
• It causes disruption of sleep cycle.

How Narcolepsy Affects Sleep

• People with narcolepsy have a disrupted sleep cycle, skipping to REM sleep instead of cycling through the initial sleep stages.
• People without narcolepsy enter REM sleep after 60-90 minutes, while people with narcolepsy enter REM after 15 minutes.
• It happens because the hypothalamus manages the sleep-wake cycle, and narcoleptic individuals have a shortage of orexin.
• Caused by genetic mutation, developed after influenza, or brain injuries.
• There is no direct cure for narcolepsy, but there are methods of combating it by medication, short naps, regular sleep schedule, avoiding caffeine/alcohol, CBT, exercise, healthy diet, relax before sleep, and safety measures when driving.

Types of Narcolepsy

• Narcolepsy Type I: involves cataplexy (20% of cases).
• Narcolepsy Type II: does not involve cataplexy (80% of cases).

Diagnosing Narcolepsy

• It is a lengthy and difficult process, and often mistaken for other illnesses because it is rare, it affects approximately 25-50 people globally per 100,000.
• It is common in those in their late teens and early twenties.

Methods to Diagnose Narcolepsy

• Sleep study (polysomnogram or PSG): Tracks aspects of sleep such as brain waves, heart rate, breathing, leg movements, and eye movements.
• Multiple Sleep Latency Test (MSLT): Observes the ability to fall asleep during the day.
• Maintenance of Wakefulness Test (MWT): Tests an individual's ability to overcome daytime sleeping situations.
• Spinal tap (lumbar puncture): Observes genetics to determine amount of Orexin, permitting early diagnosis but it only works for type 1 narcolepsy.

Hypnosis

• Similar to a trance, where one is still awake but very relaxed and open to suggestions.
• A hypnotist guides, helps relax, and offers suggestions, but the individual remains in control.
• Process involves being in a calm, quiet place, focusing on one thing, and being open to ideas when relaxed enough.
• Hypnosis does not cause loss of control but you remain aware, 5-20% of people cannot be hypnotized, and 15% are super easy to hypnotize. People who get lost in books or movies, or daydream a lot, are the best candidates.

Uses for Hypnosis

• Hypnosis can be used to manage pain, help fight addictions, address mental health issues like anxiety or phobias, and boost focus for athletes.
• Hypnosis mainly affects parts of the brain linked to attention, awareness, and control.
• These include the anterior cingulate cortex and prefrontal cortex.

Impact of Hypnosis

• The brain zones in and shuts out noise.

Drugs

• Drugs affect the brain by acting like neurotransmitters, mimicking them to activate receptors (agonist), or blocking them (antagonist), and may cause sensitization or tolerance.
• Sensitization means your brain reacts more strongly and less of the drug is needed.
• Tolerance leads to the body getting used to the drug and stops making its own similar chemicals.
• Withdrawal occurs when stopping the drug after building tolerance, leading to feeling bad or uncomfortable.

Defining Dependence

• Physical dependence (addiction) - brain depends on the drug, causing withdrawal when stopped.
• Psychological dependence - feeling like the drug is needed to feel good or be in a certain mood.
• Psychoactive drugs affect mental processes and behavior by temporarily changing how neurons are excited or inhibited because psychoactive drugs can pass through the blood-brain barrier and directly affect the brain's activity.

Stimulants

• Affect the CNS by increasing heart rate, BP, and muscle tension.
• They buildup dopamine, interfere with serotonin, and block nerve impulses, increasing attentiveness, mood, and preventing people from feeling pleasure (addiction).

Coffee

• Coffee is the world's most used psychoactive drug.
• It enters the bloodstream and passes through the blood-brain barrier quickly.
• Caffeine's half-life is between two to four hours, at which point half of it has left the body's cells. The benefits of moderate caffeine consumption are multifold and include:
  • Boosting immune system function.
  • Containing multiple antioxidants.
  • Lowering rates of skin cancer, Parkinson's Disease, and Alzheimer's Disease.
  • Counteracting increased immoral actions, such as dishonesty or theft.

Costs of Caffeine Usage

• Caffeine ingestion of 200mg a day of caffeine doubles the likelihood of a miscarriage if taken by a pregnant woman.
• Caffeine can cause a spike in glucose levels, which can be problematic for people with type II diabetes.
• Withdrawal from caffeine includes irritability, fatigue, headaches, and difficulty concentrating.
• In ADHD, stimulants block reabsorption, allowing the neurotransmitter to transfer regularly.

Amphetamines

• Strong stimulants.
• Small amount can increase energy, alertness, talkativeness and confidence.
• Too much can lose appetite, increase anxiety and irritability.
• Long usage can increase anxiety and irritability.
• Cocaine: Dopamine is blocked from reuptake, flooding with pleasure dopamine, rewiring the brain to reach dopamine levels to a normal.
• Depressants cause neurons to fire slowly, causing slurred speech, poor judgement, aggressive action, and memory reduction.
• Narcotics: Increase relaxation and relieve pain and anxiety, creates rush of positive feeling then euphoria that lasts 3-5 hours, creates addiction.
• Hallucinogens: MDMA & LSD affect operation of serotonin in the brain and alter brain cell activity to change what they see
• Hallucinagens cause changes in colour, sound, shapes, time and trigger flashbacks.
• Adderall is a mix of amphetamine and dextroamphetamine.

Uses of Adderall

• Adderall is most used for treating ADHD and Narcolepsy
• Adderall causes an increase in Dopamine, epinephrine and norepinephrine levels.
• In ADHD, Adderall regulates overstimulation and allows people to be more focused and increases wakefulness.
• In an average person, Adderall overstimulates the brain.
• Increasing neurotransmitter levels creates this euphoric feeling why some people take it to get high.
• It also makes one feel lighter by reducing stress, increasing wakefulness, improving focus and making them more productive.
• These positive effects have caused high school and university students to abuse the drug to increase productivity.

Consequences/Side Effects of Adderall

• Addiction is likely for those who take Adderall for a long period of time.
• Side effects include being stuck” in Sympathetic mode. Adderall puts the brain in "fight or flight" mode, raising blood pressure, constricting blood vessels, and increasing risk of heart issues.
• Other common side effects may include decrease in weight, loss in appetite, dryness in mouth, issues in digestion, disruption in sleep, depression, anxiety, mood swings, and nausea.
• Adderall increases neurotransmitters and inhibits their reuptake and removal.
• Scientific proof that Adderall is good, amongst 75%-80% of people with ADHD have seen a reduction of their ADHD symptoms.
• It has allowed people with ADHD to tackle higher education and in a sample size survey, 2% of college students in the US were known to have ADHD, as of 2020 that number had risen to 11.6%, showing a significant impact that Adderall has had on people's lives.
• 12 year old girl who had ADHD and was treated with Adderall and the drug caused extreme anxiety to the extent that she formed an urge to pull out her hair and was diagnosed with Trichotillomania and her doctors concluded that Adderall was the cause of the disorder.
• Another study funded by the National Institute of Mental Health (NIMH) had discovered links between frequent Adderall usage and psychosis and that 81% of cases of psychosis could have been prevented if the dosage of amphetamines (a major component of Adderall) was lower.

Senses and Perception

• Sensation - process senses of vision, hearing, and smell by receiving and relaying outside stimuli.
• Perception - how the brain organizes and interprets information.

Eyes

• Cornea: Clear outer covering that focuses light.
• Iris: Colored muscle that opens and closes to control the amount of light entering.
• Lens: Allows focus on an object.
• Pupil: Eye hole that allows light.
• Blind Spot: No receptors because it connects to the optic nerve.
• Retina: Millions of receptors: Light cause chem and elec events that trigger nerve impulses.
• Muscle: Controls the shape of the lens.
• Vitreous body: Gel that fills space.
• Optic Nerve: Transmits visual info from the retina to the brain.
• Rods: Only see black & white, use for low light.
• Cones: Provide sharpness of vision and colour, operate best at high light.
• Aqueous humour: Clear fluid between lens and cornea.
• Supersensory ligament: Fibers that connect eye w/ lens holding it in place.
• Choroid: Protective membrane.
• Conjunctiva: Protective membrane.

Ears

• External and internal ear (hearing), middle ear (hearing and equilibrium)
• Outer skin: Pinna or auricle that catches sound waves and passes them into the ear.
• Travel down Ear Canal to the middle and inner ear.
• Tympanic Membrane or Eardrum: Entrance to middle ear-it vibrates sound back and forth to push through tiny bones into their middle ear.
• Tympanic Cavity the relay station between outer and inner ear, mainly responsible for amplifying sound so it hits harder when it gets to the inner ear inner ear moves sound through fluid so it's harder to move-amplifying helps.
• Auditory Ossicles sound amplifiers: Malleus (Hammer) connects to inner eardrum moves vibrates, other end and of hammer hits Incus (Anvil), connects to Stapes (Stirrup), Stirrup passes vibrations into the Superior Oval Window, which sets the fluid in motion inside inner ear .
• The Inner Ear is called the Labyrinth (because it's all twisty).
• Inside the Bony Labyrinth, there's a Membranous Labyrinth, which is full of fluid and little sacs, that all move to Cochlea (snail shell) which have special membrane, that helps process and break down the sound into something your brain can understand.
• Auditory Nerve (aka cochlear nerve) steps in-picks up electrical signals from the cochlea and sends them to brain.
• Semicircular Canals (organs of balance), balance detectors.
• Eustachian Tube connects middle ear to back of our throat balances air pressure, so eardrum don't bulge too much.