Chapter 4 All Key Terms

Change blindness

When people fail to notice changes in their environment, often shown in experiments like swapping one person for another.

Example: You get a haircut, but your friend doesn’t realize it until you mention it.

Chronotype

Whether someone is naturally a morning person (lark) or a night person (owl), based on their activity patterns.

Example: Some people feel energized in the morning (larks), while others are more active at night (owls).

Circadian rhythm

The body’s 24-hour internal clock that controls sleep, energy levels, and other functions.

Example: Feeling sleepy at night and waking up in the morning without an alarm.

Homeostasis

The body’s way of keeping balance, like maintaining a stable temperature or energy level.

Example: Sweating when you're hot to cool down.

Melatonin

A hormone that helps regulate sleep and biological rhythms, produced by the pineal gland.

Example: Your body produces more melatonin at night to make you feel sleepy.

Selective Attention

Focusing on one thing while ignoring others, like shining a spotlight on specific information.

Example: Reading a book in a noisy café while ignoring background chatter.

Stream of consciousness

William James’s idea that thoughts flow continuously, like a never-ending river of mental activity.

Example: When you're lying in bed, your thoughts might jump from remembering what you ate for lunch to thinking about a vacation, then to an old song playing in your head—all blending together without clear pauses.

Electroencephalography (EEG)

A tool to measure brain activity, often used to study different sleep phases.

Example: Doctors use an EEG to track brain waves and diagnose sleep disorders like insomnia or sleep apnea.

Evolutionary psychology

The study of how behaviors and thinking patterns have developed over time through natural selection.

Example: Evolutionary psychologists might study why humans have a natural fear of snakes, suggesting it helped our ancestors survive by avoiding dangerous animals.

Homeostatic regulation of sleep

The body’s way of balancing sleep by making you sleep longer or fall asleep faster after being sleep-deprived.

(a general sleep-balancing system)

Example: If you haven't slept well for a few nights, your body may make you feel more tired and encourage you to sleep longer the next time you do sleep, helping to restore balance.

National Sleep Foundation

An organization that shares how sleep improves health, mood, memory, and stress levels.

Example: The National Sleep Foundation provides guidelines on how many hours of sleep people should aim for based on their age, along with tips for better sleep hygiene, like maintaining a regular sleep schedule and creating a comfortable sleep environment.

Pineal gland

A gland that releases melatonin, helping control sleep cycles and biological rhythms.

Example: The pineal gland produces more melatonin in the evening, signaling to your body that it's time to sleep, and reduces melatonin production in the morning to help you wake up.

Pituitary gland

A gland that produces hormones during sleep, supporting growth, reproduction, and body development.

Example: The pituitary gland releases growth hormone during deep sleep, which helps in tissue growth and repair, playing a crucial role in physical development, especially in children and adolescents.

Predatory risks

The idea that sleep patterns evolved to protect humans from predators by staying inactive during dark, risky times.

Example: Early humans may have developed a sleep schedule that involved being less active at night when predators were more likely to hunt, allowing them to stay safe and avoid dangerous encounters while they were vulnerable during sleep.

Sleep rebound

When a person who hasn't slept enough falls asleep faster and sleeps longer to recover from being tired.

(Is the body’s reaction to a lack of sleep)

Example: If a student stays up late studying for exams and only gets a few hours of sleep, they may find that after the exam, they fall asleep quickly and sleep for a longer duration the next night to make up for the lost sleep.

Sleep-wake cycles

Are the daily patterns of when we sleep and when we wake up, managed by areas in the brain like the hypothalamus and pons.

Example: going to bed around 10 PM and waking up at 6 AM every day. During this time, your body goes through different stages of sleep and then naturally wakes up in the morning, following a consistent routine.

Abuse potential

The chance a drug can be misused or cause addiction.

Example: Opioids like oxycodone have a high abuse potential because they can create feelings of euphoria, leading some people to misuse them.

Acetylcholine

A brain chemical that helps with movement, alertness, and learning.

Example: Helps you move your muscles when you walk or pick up an object also involved in memory and focus.

Addictive disorders

Conditions where individuals continue to use drugs despite negative consequences, as classified in the DSM-5.

Example: A person may struggle with alcohol addiction, drinking excessively even when it harms their health and relationships.

Agonist

A substance that boosts the activity of brain chemicals.

Example: Morphine is an agonist that mimics the effects of natural pain-relieving chemicals in the brain, providing pain relief.

Analgesic

A drug that reduces pain, like opioids (e.g., heroin, morphine).

Example: Ibuprofen is an analgesic that helps reduce mild to moderate pain, such as headaches or muscle aches.

Antagonist

A substance that blocks or reduces the effect of brain chemicals or neurotransmitters from working.

Example: Naloxone is an antagonist that blocks the effects of opioids, helping to reverse an overdose.

Barbiturates

Drugs that slow down brain activity by boosting GABA.

Example: Phenobarbital is a barbiturate often used to treat seizures and anxiety.

Benzodiazepines

Drugs that reduce anxiety and promote relaxation by increasing GABA.

Example: Xanax (alprazolam) is a common benzodiazepine used to treat anxiety and panic disorders.

Codeine

Is a mild opioid medication used to relieve pain and reduce coughing.

Example: Codeine is often prescribed for treating mild to moderate pain after surgery or for cough relief in cold medications.

Depressants

Are substances that slow down brain activity and can reduce feelings of anxiety and promote relaxation.

Example: Alcohol is a common depressant that can impair judgment and coordination while making a person feel more relaxed.

Dopamine

Is a neurotransmitter in the brain that plays a key role in pleasure, reward, and motivation.

Example: When you eat your favorite food, dopamine is released, making you feel happy and encouraging you to seek out that food again.

Euphoria

Is a state of intense happiness or pleasure, often experienced after using stimulants or certain drugs.

Example: After taking a stimulant like cocaine, a person might feel a strong sense of euphoria, experiencing heightened energy and happiness.

Gamma-aminobutyric acid (GABA)

A brain chemical that slows down brain activity.

Example: It helps reduce anxiety and is boosted by drugs like benzodiazepines.

Hallucinogens

Are drugs that alter sensory perceptions and can cause visual or auditory hallucinations.

Example: LSD is a common hallucinogen that can make users see or hear things that aren’t there.

Hypnosis

Is a focused state of attention and heightened suggestibility, often used for therapeutic purposes.

Example: A therapist may use hypnosis to help a patient manage anxiety or pain by suggesting relaxation techniques.

Meditation

Is the practice of focusing your mind on a single thought or object to promote relaxation and mindfulness.

Example: Someone sits quietly and focuses on their breath to reduce stress and improve focus.

Methadone

Is a man-made opioid that helps relieve withdrawal symptoms in people recovering from opioid addiction.

Example: A person undergoing treatment for heroin addiction might take methadone to help manage cravings and reduce withdrawal discomfort.

Opioids

Are a class of drugs that help relieve pain, including natural substances like morphine and synthetic ones like methadone.

Example: A doctor might prescribe oxycodone, an opioid, to a patient recovering from surgery to help manage their pain.

Physical dependence

When the body adapts to a drug and reacts badly if it’s stopped.

Example: Someone who has been taking pain medication for a long time may experience nausea, shaking, or anxiety if they suddenly stop taking it.

Psychoactive medications

Are drugs that affect brain function and alter mood, perception, and consciousness.

Example: Antidepressants like fluoxetine (Prozac) change mood and emotional states, helping people with depression feel better.

Serotonin

A brain chemical affecting mood, often altered by drugs like LSD.

Example: Drugs like LSD can significantly change serotonin levels, leading to altered mood and perceptions.

Stimulants

Are drugs that increase brain activity, leading to heightened alertness and energy.

Example: Caffeine, found in coffee, and cocaine are common stimulants that can enhance focus and reduce fatigue.

Substance use disorder

Is a harmful pattern of drug use that leads to significant issues in a person's life, as outlined in the DSM-5.

Example: An individual continues to use alcohol despite experiencing negative consequences, such as job loss or relationship issues.