Consciousness, Sleep, and Memory: Key Concepts and Disorders

Consciousness

A state of awareness - both inner and outer awareness.

Dynamic

You're awake, aware, and alert.

Arousal

You must be awake.

Awareness

You have to be aware of your surroundings.

Altered Consciousness

Can be altered via sleep or drugs.

Unconsciousness

A lack of awareness.

Coma

The person is unable to respond to the external; typically on machines to stay alive.

Vegetative State

One step above coma; may breathe on their own and occasionally open their eyes but unable to interact meaningfully.

Minimally Conscious State

Best of the three; may exhibit signs of consciousness occasionally and interact with the environment but not continuously.

Automatic Processes

Some things in humans are always working and considered automatic; learned behaviors done without thinking.

Priming

Our consciousness can fall victim to priming; earlier stimulus affects later events.

Amygdala

Emotional center responsible for feelings like fear or anger.

Period of 10-15 minutes

Duration for which the amygdala remains activated after an emotional stimulus.

Subliminal Messages

Quick images shown to influence behavior, though they don't work well.

Circadian Rhythms

Biological clocks that last about a day, regulating sleep, wakefulness, hormone production, and temperature.

Average Sleep Requirement

The average for needed sleep is 8 hours, but individual needs can vary from 3 to 12 hours.

Biological Clock Variation

Can vary from 24.2 to 25.75 hours.

Sleep Deprivation

A stressor that can affect consciousness.

Sleep

A behavior, not the absence of behavior; humans can delay sleep but eventually need it.

Mammoth Cave Experiment

Participants were placed in a dark cave to test if biological clocks could be altered, but results showed no change.

Second Wind

Feeling of renewed energy after staying up all night; not an actual second wind, just the waking phase.

Brain-Washing

Always a part of brain-washing because people are much more susceptible to crazy ideas when they're sleep deprived.

Polysomnograph

A polysomnograph is used in sleep research to measure brain activity and eye movements.

EEGs

EEGs is how scientists first realized there were stages of sleep.

Nonrem Sleep

Stages 1-4 are considered Nonrem sleep.

REM Sleep

REM sleep is characterized by beta waves and occurs after about 90 minutes of sleep.

Beta Waves

When you're aroused and alert, you show beta waves.

Alpha Waves

When you're relaxed, alpha waves show up.

Stage 1 Sleep

Transition stage between sleep and wakefulness where hypnogogic hallucinations are common.

Hypnogogic Hallucinations

Dream-like experiences that relate to reality, occurring when you're falling asleep.

Stage 2 Sleep

The patient is actually asleep but may swear they weren't if woken up.

Slow Wave Sleep (SWS)

Stages 3 and 4 are known as slow wave sleep where the brain completely stops sending sensory information.

Heart Rate and Breathing

As you go through the stages of sleep, heart rate, breathing, and brain activity decrease.

REM Stage Characteristics

In REM stage, beta waves show up, heart rate and breathing are up, and muscle atonia occurs.

Muscle Atonia AKA sleep paralysis

is when postural muscles are most relaxed to prevent acting out dreams.

Evolutionary Theory of Sleep

Some believe sleep is similar to hibernation, keeping us out of harm's way when we'd be inefficient.

Restoration Theory

Sleep allows the brain to repair and restore itself after the exertions of the day.

Cerebral Spinal Fluid

coats the brain and helps remove waste during sleep.

Information Processing Theory

Sleep is critical for memory formation; activity from the day replays itself during REM sleep.

Memory Formation Study

In a study, rats that slept after learning an activity showed memory recall, while those that did not sleep did not remember.

Three Models of Sleep and Memory

involve both slow wave sleep and REM.

Effects of REM Deprivation

the body's attempts to enter REM increase, leading to mood alterations and potential hallucinations.

Dreaming in Sleep

You do dream in REM but can also dream in other stages of sleep.

Behavior of Sleep

Sleep is a behavior, not the absence of one.

Dyssomnias

Disorders that involve falling or remaining asleep.

Insomnia

Not getting enough sleep for your unique needs.

Diagnosis of insomnia

Difficult to obtain; requires 3 straight weeks of inadequate sleep and ruling out other factors.

Prevalence of insomnia

Common medical problem affecting 8-10% of people, most prevalent in older females.

Hyper-arousal in insomnia

People with insomnia often feel exhausted but do not report being sleepy.

Onset insomnia

Difficulty falling asleep.

Maintenance insomnia

Difficulty staying asleep, characterized by multiple awakenings throughout the night.

Termination insomnia

Waking up too early and unable to return to sleep.

Cause of insomnia

Stress may trigger onset, but it can become self-sustaining.

Best treatment for insomnia

Cognitive Behavioral Therapy (CBT) focusing on sleep hygiene.

Sleeping pills

Often ineffective; may last too long or not long enough.

Melatonin

Should not be taken nightly; excessive use can disrupt natural production.

Iatrogenic insomnia

Insomnia caused by medication.

Apnea

Disorder characterized by interrupted breathing during sleep.

Obstructive sleep apnea

Caused by fat tissue pressing on the windpipe, preventing airflow.

Correlation between obesity and sleep apnea

There is a direct link; many are unaware they have it until informed by a partner.

CPAP

Common treatment for sleep apnea that pumps air into the lungs via a mask.

Narcolepsy

Characterized by unexpected periods of sleep during wakefulness.

Microsleeps

Very short sleep periods that can last only a few seconds.

Genetic component of narcolepsy

Not fully identified in humans, but has been observed in other animals.

Cataplexy

Unexpected periods of REM sleep with muscle paralysis, causing sudden drops.

Xyrem

A drug that reduces cataplexy by promoting better sleep at night.

REMS program

A federal program required for doctors and pharmacies to provide Xyrem due to its potential risks.

Side effects of Xyrem

Can cause respiratory depression and must be closely monitored.

Parasomnias

Characterized by unwanted behaviors occurring during the sleep period, often due to partial awakening.

REM Behavior Disorder

Individuals act out their dreams due to lack of muscle atonia, which normally paralyzes postural muscles during sleep.

Colanzapam

An antiseizure medicine that is a CNS depressant, with a 90% working rate.

Sleepwalking

Occurs most often in children around ages 2-5, does not occur during REM, usually in stage 3 or 4, and is not accompanied by dreaming.

Sleeptalking

Normal occurrence at all stages of sleep, with no correlation between dreams and what is being said.

Night Terrors

Occur when an individual wakes up in a panic, with no idea why, and are different from nightmares.

Lucid Dreaming

When you are aware of your dream and think you can control it.

Hypnosis

Considered a placebo effect with no experimentally designed studies to validate it as a fact.

Meditation

A method of decreasing sympathetic arousal, which helps reduce stress.

Psychoactive Drugs

Chemically alter consciousness and can be legal (like caffeine) or illegal (like heroin).

Dopamine

The reinforcement neurotransmitter that all drugs cause the release of.

Depressants

Slow the normal functions of the CNS, may decrease anxiety, help with sleep, and include tranquilizers like sedatives, benzos, and alcohol.

Alcohol

The most widely/readily abused sedative drug in the US, binds to many of the same receptors as benzodiazepines, and is incredibly toxic to unborn children.

Benzodiazepines

The drug of choice for anxiety, previously replaced barbiturates due to issues.

Genetic Component of Sleep Disorders

Some sleep disorders, like sleepwalking and REM behavior disorder, have a hereditary aspect.

Sleepwalking Defense (Court)

Has been used as a murder defense, with only one successful case recorded.

Waking Someone Up While Sleepwalking

It's fine to wake someone up while they're sleepwalking; it's not dangerous.

Brain Activity During Dreaming

The limbic system is active, making dreams emotional, while the prefrontal cortex is shut off, preventing memory of dreams.

Drug Reinforcement

Any drug that is reinforcing works on a particular brain area responsible for reinforcement, increasing the likelihood of repeated use.

CNS Depressants

Drugs that may decrease anxiety and lower inhibitions, potentially leading to dangerous combinations.

Cognitive and Physical Effects of Alcohol

Alcohol consumption during pregnancy can lead to unfavorable cognitive and physical qualities in unborn children.

Schedule Drugs

Marijuana is classified as a schedule 1 drug, and research testing it on humans is now allowed.

Effective dose

Very close to lethal dose, that's why benzos are now used.

Sedative drugs

A class of depressants that decrease anxiety.

Inhalants

Sniffing things like glue and markers and such. Gives a high.

Depressant drug

Kill you real fast. Kill brain cells.

Opiates

Used medically to prevent or relieve pain. Very rarely addictive when used in medical settings.

Self-administered morphine study

Patients in hospital were allowed to self administer morphine when they felt pain. Most gave themselves less than the regular dosage.

Euphoria and drowsiness (cause)

opioids that include morphine, heroin, codeine, oxycodone, hydrocodone and fentanyl

Example of opiate

Morphine.

Heroin

Most common and very addictive. Same drug as morphine but way stronger.

Blood-brain barrier

Heroin crosses the blood-brain barrier faster than morphine.