AP Psychology Notes

AP Psychology Notes: Unit 1 - Scientific Foundations of Psychology

  • Psychology: Science of mental processes and behavior; constantly evolving with new theories.
  • Studied since the Stone Age.
  • Trephination: Ancient practice of carving holes in the skull to release evil spirits.
  • Phrenology: Determining personality by feeling the bumps on the head

Psychological Perspectives

  • Psychological Perspectives: Different theories on how the mind works and influences behavior.
  • Structuralism:
    • Uses experimental introspection to analyze the five senses and conscious experience.
    • Created by Wilhelm Wundt.
    • No longer followed.
  • Functionalism:
    • Mental processes serve survival and adaptation functions.
    • Created by William James, who criticized Wundt.
    • No longer followed.
  • Gestalt:
    • The whole is greater than the sum of its parts.
    • Connected to perception.
    • Created by Max Wertheimer.
  • Psychoanalytical:
    • Actions controlled by the unconscious mind and childhood experiences.
    • The unconscious mind protects itself from harmful information.
    • Created by Sigmund Freud.
  • Behavioralism:
    • People react to their environment.
    • Focuses only on observable actions.
    • Created by Watson, Skinner, and Pavlov.
  • Neuroscience/Biopsychology:
    • Studies the brain, neurons, chemicals, and genetics to understand their influence on behavior, memory, emotions, and senses.
    • Takes a medical approach to psychology.
  • Evolutionary/Darwinian:
    • Focuses on natural selection and how evolution/adaptation has shaped the mind and behavior.
    • How humans have psychologically adapted over time.
  • Cognitive:
    • Examines human thoughts and behaviors in terms of structures and logic.
  • Humanist:
    • Stresses individual choice; free will can help achieve full potential.
    • Created by Maslow and Rogers.
  • Socio-Cultural:
    • Looks at how people's thoughts and behaviors are influenced by the people/culture around them.
  • Eclectic Psychology:
    • A combination of all styles for a complete understanding of psychology.
    • Needed to best treat psychological disorders.

Specialties in Psychology

  • Research Psychology:
    • Builds the knowledge base of psychology.
    • Includes laboratory research and information-gathering research.
  • Applied Psychology:
    • Psychological research and practice developed in real-life situations.
  • Clinical:
    • Studies, assesses, and treats people with psychological disorders.
  • Community:
    • Studies how people interact with their social environments and how social institutions affect individuals and groups.
  • Counseling:
    • Assists people with problems in living and achieving greater well-being.
  • Developmental Psychologist:
    • Observe, interview, and interact with children and adolescents to understand what they are dealing with.
  • Experimental:
    • Run experiments to study human behaviorism and mental phenomena.
    • Use findings to inform diagnoses and treatments for various social, behavioral, and emotional disorders.
  • Industrial/Organizational:
    • Application of psychological concepts and methods to optimizing human behavior in workplaces.
  • Educational Psychologist:
    • Studying influences on teaching and learning.
  • School Psychologist:
    • Works with school-aged children and young adults.
    • Listens to concerns about academic, emotional, and social problems, assists students with their problems, plans goals, and is involved with research and implementing learning programs.
  • Social Psychologist:
    • Typically works in universities or government agencies and develop solutions to certain social problems.
  • Forensic Psychologist:
    • Applies psychology to the justice system.

Research Methods

  • Case Study:
    • In-depth research of one or a few individuals over a long period of time.
    • Helpful in finding universal information but can be misleading if the person is not "normal."
  • Survey:
    • Asks people about their thoughts, feelings, or opinions to get a general consensus.
    • Wording Effect: Subtle changes in word choice can alter people’s answers.
    • Random sampling of the population is extremely important.
    • People can lie.
  • Naturalistic Observation:
    • Observing people in their own environment without interfering.
  • Experiments:
    • Manipulating variables in a controlled environment to find a cause-and-effect relationship.
  • Correlation Study:
    • Comparing the relationship between two variables without showing cause and effect.

Components of the Experimental Method

  • Experimental Method: Finding cause-and-effect relationships by manipulating variables.
    • Create a hypothesis (an educated guess).
    • Asking and answering a question (using the scientific method).
  • Laboratory Experiments:
    • Conducted in a lab in a highly controlled environment.
  • Field Experiments:
    • Conducted in the real world with as much control as possible.
  • Independent Variables:
    • The variable being manipulated (the thing being changed).
  • Dependent Variables:
    • The variable being measured (changed by the independent variable).
  • Operational Definition:
    • Clearly defining the variables.
  • Sample Group:
    • The group you are researching from your population.
  • Population:
    • The larger group from which your sample comes.
  • Random Sampling:
    • Picking the sample from the larger population so that every person has an equal chance of getting chosen.
  • Stratified Sample:
    • Dividing the population into smaller populations to ensure that all groups are represented.
  • Experimental Group:
    • The group that is being manipulated by the independent variable.
    • Hawthorne Effect: Participants' performance is affected by being in the experimental group, regardless of the experiment.
  • Control Group:
    • Not being changed in any way and used as a comparison group to the experimental group.
  • Group Matching:
    • Getting an even amount of characteristics.

Experimental Bias

  • Researcher Bias:
    • The unconscious tendency for researchers to skew findings to prove their hypothesis.
  • Response/Subject Bias:
    • When subjects act the way they think they should.
    • Demand Characteristics: Cues from the study that subjects might try to meet.
    • Social Desirability: Subjects do what they think is politically correct.

Methods of Control

  • Placebo:
    • Giving a fake substance or situation to see the effects of the real substance.
    • Works with medicine, drugs, and alcohol.
  • Counter Balancing:
    • Using the experimental group as the control group.
    • Ordering Effects: May change the outcome (experimental 1st compared to control 1st).
  • Single-Blind Experiment:
    • Subjects do not know if they are in the control or experimental group.
  • Double-Blind Experiment:
    • Both subject and researcher do not know the group assignments (third party must keep records).
  • Validity:
    • The accuracy of the research. Is the test measuring what it should be measuring?
  • Reliability:
    • Consistency of the research. All experiments must be able to be repeated with similar results to be considered meaningful.

Statistics in Psychology

  • Correlation Method:
    • Shows the relationship between two variables without cause; no manipulation.
  • Positive Correlation: The variables will move together; increase or decrease.
  • Negative Correlation: The two variables move in opposite directions. As one variable increases, the other variable decreases.
  • Correlation Scale (Coefficients): Shows the strength of the relationship between two variables.

-1 \leftarrow 0 \rightarrow +1

  • Perfect Positive (+1): They move together perfectly (increase or decrease together).
  • 0: There is no correlation; one has nothing to do with the other.
  • Perfect Negative (-1): As one increases, the other decreases perfectly.
  • Descriptive Statistics: Simply describing a set of data.
  • Frequency Distribution: Shows how often an event occurs (graphs, charts, etc.).
  • Scatter Plots: Mapping out points to show relationships.
  • Line Of Best Fit: Drawing a line that goes through most points on a scatter plot.

Central Tendencies

  • Mean: Average.
  • Median: Middle.
  • Mode: Most.
  • All equal if the distribution is equal. Skewed when the distribution is unequal.

Distributions

  • Normal Distribution:
    • Mean, median, and mode are equal, symmetrical.
  • Positively Skewed:
    • One extremely high score pulls the results.
    • The mean is higher than the median; asymmetric.
  • Negatively Skewed:
    • One extremely low score pulls the results.
    • The median is higher than the mean; asymmetric.

Variability

  • Range: Distance between highest and lowest score.
  • Variance: The distance between any score and the mean.
  • Standard Deviation: The square root of the variance (z score).
  • Z Score: Measures the distance of a score from the mean in units of standard deviation.

Inferential Statistics

  • Determine whether or not findings can be applied to the larger population.
  • Sampling error: How the sample differs from the population.
  • I.S. Tests: T-tests, ANOVAs, and MANOVA.
  • P-Value: Shows the significance of the findings (how far your sample group is from the larger population). The smaller the p-value, the more significant the results; can never be 0.

Ethical Guidelines in Psychology

  • APA Ethical Guidelines (APA): Created these rules to protect all subjects in psychological testing or treatment.

Ethical Guidelines for Animal Research

  • There must be a clear scientific purpose.
  • Be humane; must care for and house animals in a humane way.
  • Acquire animals legally from accredited companies. If wild animals are needed, they need to be trapped humanely.
  • Least amount of suffering feasible.

Ethical Guidelines for Human Research

  • Informed consent (permission).
  • Avoid deception (if needed, it cannot invalidate informed consent).
  • No coercion.
  • Anonymity.
  • No significant risk.
  • Debriefing (results) must be offered to the subject at the end of the research.

Review Committees

  • International Review Board (IRB): Reviews research studies involving human subjects.
  • Institutional Animal Care And Use Committee (IACUC): Reviews research involving animals for ethics violations.

Unit 2: Biological Bases of Behavior

Structure of the Neuron

  • Neuron: Highly specialized cells used to send signals throughout the nervous system.
  • Dendrite: Short fibers that branch out from the cell body and pick up incoming messages.
  • Cell Body: Made up of a nucleus which contains a complete set of chromosomes and genes; cytoplasm, which keeps the cell alive; and a cell membrane, which keeps the cell enclosed.
  • Axon: Single long fiber extending from the cell body; it carries outgoing messages.
  • Myelin Sheath: White fatty covering on axons. Increases the speed in which the message is sent and protects the nervous system.
  • Demyelization Disease: Multiple Sclerosis (MS).
  • Glial Cells: Cells that form the myelin sheath; they insult and support neurons by holding them together, remove waste products and prevent harmful substances from passing into the bloodstream into the brain.
  • Terminal Button (Synaptic Knob): Structure at the end of an axon terminal branch.
  • Synaptic Vesicles: Tiny sacs in a terminal button that release chemicals (neurotransmitters) into the synapse.
  • Synaptic Cleft: Tiny gap between the axon terminal of one neuron and the dendrites or cell body of the next neuron.
  • Synapse: Area composed of the axon terminal of one neuron, the synaptic space, and the dendrite of the next neuron.
  • Neurotransmitters: Chemicals released by the synaptic vesicles that travel across the synaptic space and trigger adjacent neurons.
  • Receptor Sites: A location on a neuron that receives incoming neurotransmitters which usually fits like a key into a lock.
  • Reuptake: The neuron sending the message will take back any neurotransmitters left in the synaptic gap.

Types of Neurons

  • Afferent (Sensory) Neurons: Carry the messages from the sense organs to the spinal cord or brain.
  • Efferent (Motor) Neurons: Carry the messages from the spinal cord or brain to the muscles and glands.
  • Interneuron (Associative Neuron): Neurons that carry messages from one neuron to another.
  • Electrically charged sodium (Na) and potassium (K) ions are activated to move in or out of a neuron to send a signal.
  • Resting Potential (Polarized): Electrical charge across a neuron membrane. Positive ions on the outside and negative ions on the inside. The neuron is doing nothing (resting).
  • Action Potential (Depolarized): The firing of a nerve cell. Positives inside and negatives outside.
  • Graded Potential: A shift in the electrical change in a tiny area of a neuron.
  • Threshold Of Excitation: The level an impulse must exceed to cause a neuron to fire.
  • All-Or-None Principle: Action potential in a neuron does not vary in strength. The neuron either fires at full strength or not at all.
  • Absolute Refractory Period: A period after firing when a neuron cannot fire again no matter how strong the incoming messages may be. The ions are already in action potential.
  • Relative Refractory Period: A period after firing when a neuron is returning to its normal polarized state and will fire again only if the incoming messages are much stronger than usual.

Neurotransmitters

  • Neurotransmitters: Chemical messages sent from one neuron to another.
  • Acetylcholine: Involved with motor (muscle) movement; involuntary/voluntary.
  • Lack is associated with Alzheimer’s disease.
  • Dopamine: Involved with voluntary motor movement, alertness, and reward/pleasure.
  • Lack is associated with Parkinson’s disease.
  • Excess is associated with schizophrenia.
  • Norepinephrine: Involved with alertness, arousal, and reward.
  • Serotonin: Involved with mood control; lack is associated with clinical depression.
  • GABA (Gamma-Aminobutyric Acid): Involved with regulating (slowing down) neural excitability. It helps to control anxiety and convulsions (seizures).
  • Endorphins: Involved with addictions/highs and the human body’s natural pain control (natural opiate).
  • Psychopharmacology: Mood altering drugs that either block or enhance the transmission of chemicals across synapses.
  • Agonist: Type of drug that mimics a neurotransmitter.
  • Antagonist: Type of drug that blocks a neurotransmitter from entering the receptor sites.
  • Reuptake: The neuron sending the message will take back any neurotransmitters left in the synaptic gap.
  • Neural Plasticity: The ability of the brain to change in response to experience or damage.
  • Neurogenesis: The growth of new neurons.

Divisions of the Brain

  • Hindbrain (Old Brain): Base of the brain mainly involved in life functions.
    • Medulla: Controls blood pressure, heart rate, and breathing.
    • Pons: Controls facial expressions, involved in sleep and alertness. Connected to the limbic system (emotions).
    • Cerebellum: Controls certain reflexes, balance, and fine motor movement.
  • Midbrain: Region between the hindbrain and forebrain; it is important for hearing, sight, and can register pain.
  • Forebrain: Largest region of the brain, with many important roles.
    • Thalamus: Relays and translates incoming messages from all of the senses other than smell (switchboard of the brain).
    • Hypothalamus: Controls motivation and emotional responses, metabolic functions (body temperature, hunger, thirst), libido (sex drive), and the endocrine system (hormones and glands).
    • Reticular Formation (RF): Network of neurons in the hindbrain, the midbrain, and part of the forebrain whose primary function is to alert and arouse the higher parts of the brain. If this doesn’t work, you will fall into a coma.

Lobes of the Brain

  • Frontal Lobe (Prefrontal Cortex): Responsible for voluntary movement, attention, goal-directed behavior, and appropriate emotional responses, thinking and decision making, and personality.
  • Parietal Lobe: Receives sensory information from throughout the body. Contains motor and sensory cortex (touch).
  • Occipital Lobe (Visual Cortex): Receives and interprets visual information.
  • Temporal Lobe: Helps regulate hearing (auditory information), balance, equilibrium, and certain emotions and motivation.
  • Cerebral Cortex (Cerebrum): The outer surface of the two cerebral hemispheres that regulates most complex behaviors (gray matter). Plays a key role in memory, attention, perceptual awareness, thought, language, and consciousness.
  • Hemispheric Specialization: The right and left side brain have different and specific functions.
    • Stronger Right Lobe: Creativity and emotion.
    • Stronger Left Lobe: Logic and language.
    • Corpus Callosum: A thick band of fibers connecting the left and right cerebral cortex.
    • Split Brain: When the corpus callosum is cut (rarely done to ease severe cases of epilepsy) causing no connection between the left side and right side of the brain. (Agenesis of the corpus callosum).

Language

  • Wernicke’s Area: Located in the back of the temporal lobe (left side); is crucial in processing and understanding what others are saying.
  • Broca’s Area: Found in the frontal lobe (left side); controls our ability to speak.

The Nervous System

  • Central Nervous System: Consists of the brain and the spinal cord which together contain 90% of the body’s neurons.
    • Brain: The main component of the central nervous system. Controls the whole body.
    • Spinal Cord: Complex cables of neurons that run down the spine, connecting the brain to most of the rest of the body.
  • Peripheral Nervous System: The way in which the rest of the body communicates with the central nervous system.
    • Somatic Nervous System: Made up of nerves that connect to voluntary skeletal muscles and sensory receptors.
    • Autonomic Nervous System: Carries involuntary messages between the central nervous system and the internal organs (heart, blood vessels, smooth muscles, and glands).
      • Sympathetic Nervous System: It prepares the body for quick action in emergencies. Slows digestion, drains blood from the periphery of the body, releases hormones (fight or flight).
      • Parasympathetic Nervous System: It calms and relaxes the body. Slows heart rate, reduces blood pressure, promotes digestion. Like a parachute bringing your body slowly back to homeostasis.
Nervous System Hierarchy:

Nervous System
↙ ↘
Central Nervous System Peripheral Nervous System
↙ ↘
Somatic Nervous System Autonomic Nervous System
↙ ↘
Sympathetic Nervous System Parasympathetic Nervous System

Tools for Studying the Nervous System

  • Microelectrode Techniques: Used to study the functions of individual neurons.
  • Macroelectrode Techniques: Used to obtain a picture of a particular region of the brain.
    • Computer Axial Tomography (CAT or CT scan): Multiple x-rays creating a 3D image.
    • Magnetic Resonance Imaging (MRI): Uses magnetic waves to produce pictures of the inner brain structure and is more detailed than the CT scan.
  • Macro: Activity of the brain.
    • EEG: Measures the brain activity on a millisecond-by-millisecond basis.
    • Positron Emission Tomography (PET): Technique that uses radioactive energy to map exact regions of brain activity.
    • Functional Magnetic Resonance Imaging (FMRI): Measures the movement of the blood molecules in the brain, pinpointing specific sites and details of neural activity.

The Endocrine and Limbic System

  • Endocrine System: Consists of glands that secrete chemicals into the bloodstream that help control bodily functioning.
    • Thyroid Gland: Produces the hormone thyroxin and regulates metabolic rate.
    • Pineal Gland: Regulates activity levels over the course of the day.
    • Pancreases: It secretes insulin and glucagon to regulate blood sugar levels.
    • Pituitary Gland: The “master gland;” it produces the hormone that influences the secretion of other glands and also secretes the growth hormone.
    • Gonads: The testes in the male and the ovaries in the female. It secretes hormones of androgens (male) and estrogen (female). Involved with secondary sex characteristics and reproduction.
    • Adrenal Glands: Two glands located just above the kidneys. Controls salt and carbohydrate metabolism; secretes hormones active in arousal, sleep, and reaction to stress (fight or flight).
  • Limbic System: Ring of structures that play a role in learning and emotional behavior. Made up of the thalamus, hypothalamus, amygdala, and hippocampus.
    • Hippocampus: Important to the way we process and receive information. Without this area, people are unable to retain new information (anterograde amnesia).
    • Amygdala: Involved in emotions and aggression.

Genes, Evolution, and Behavior

  • Genetics: Study of how traits are transmitted from one generation to the next. People are made up of 46 chromosomes (23 pairs).
  • Behavior Genetics: Study of the relationship between heredity and behavior.
    • Studying The Role Of Genetics: Important studies conducted to see the relationship between genetics and the mind and behavior.
    • Twin Studies: Identical (monozygotic) twins in comparison to fraternal (dizygotic) twins. Monozygotic twins being reared (raised) in different environments.
    • Adoption Studies: Comparing adoptive children to their biological and adoptive parents.
  • Evolution: The development of a biological group as a race or species.
  • Evolutionary Psychology: A subfield of psychology concerned with the origins of behavior and mental processes, their adaptive values and the purpose they continue to serve.

States of Consciousness

  • Consciousness: The awareness of ourselves and our environment; it’s broken up into different levels or states.
    • Nonconsciousness: The functions of the body you are not aware of. Needed to maintain life (heart rate, respiration, digestion, glands, etc.).
    • Preconsciousness: Information that you know but are not currently thinking about; your memories; can be recalled.
    • Subconsciousness: Information that we are not aware of but it affects our behavior.
    • Mere Exposure Effect: We are more comfortable around stimuli we have been exposed to (even if we don’t remember) in comparison to new stimuli.
    • Priming: An early experienced stimuli influences the response to a later stimuli.
    • Unconsciousness: Information that you are not aware of because it could be harmful to your conscious mind; psychoanalytical perspective only.

Sleep

  • A state of consciousness in which we are aware of ourselves and our environment but less aware than when you’re awake; needed for survival.
    • Typical Sleep Needs
    • Infants: 16 hours
    • Babies And Toddlers: 10-14 hours
    • Children: 3-6 years: 10-12 hours, 6-9 years: 10 hours, 9-12 years: 9 hours.
    • Teenagers: 9 hours
    • Adults: 7-8 hours
    • Older Adults: 7-8 hours

Sleep Cycle

  • The normal pattern our body cycles through, about every 90 minutes, during uninterrupted sleep.
    • Circadian Rhythm: Our biological clock; regular bodily rhythms that occur on a 24-hour cycle and are involved with temperature and wakefulness.
    • Sleep Onset: A transition between awake and sleep; can experience minor hallucinations.
    • Stage 1: Very Light Sleep: Alpha waves (brain) slows, muscles relax, easily awoken. Typically lasts around 10-15 minutes.
    • Stage 2: Light Sleep: Heart rate slows, body temperature decreases, sleep spindles, and K-complexes occur.
    • Delta Sleep (Stages 3 and 4): Deep Sleep: Brain waves slow to long delta waves, it’s hard to be awoken, muscles become active. This stage is the deepest sleep.
    • REM (Rapid Eye Movement): Dreaming.
    • Paradoxical Sleep: Brain waves are active and look like you are awake.
    • REM Rebound: If you are sleep deprived, your body will go into long periods of REM to make up for lost time. This proves that REM is essential for our health.

Sleep Disorders

  • Insomnia: Having difficulty falling and/or staying asleep for an extended period of time, leaving you tired all the time.
  • Narcolepsy: Uncontrollably falling into a deep sleep. This is dangerous and can usually be helped by stimulant medications.
  • Sleep Apnea: Periods in which you stop breathing during sleep. It’s life-threatening and CPAP machines can be used as treatment in which they force air into your nasal passages.
  • Night Terrors: An extremely terrifying experience that you will not remember. It usually occurs during Stage 4 of the sleep cycle and it’s not a dream.

Dreams

  • Stories that our mind creates during REM. They are scientifically proven that they’re essential to our mental wellbeing. No scientific facts about why we dream but there are many theories.
    • Dream Theories
    • Psychoanalytical Theory: Freud’s theory that our dreams contain hidden meanings that reveal the secrets of our unconscious mind.
    • Manifest Content: The actual story of the dream.
    • Latent Content: The hidden meaning behind the manifest dream.
    • Activation-Synthesis Theory: Dreams are biological phenomena of neurons randomly firing.
    • Information-Processing Theory: Your dreams are insight into the concerns of your life. If you are more stressed, you will dream longer. Dreams help us to work out problems and deal with stress.
  • Lucid Dreams: When a person knows that they are dreaming and can control their actions in their dreams.

Hypnosis

  • An interaction in which the hypnotist suggests to the subject certain perceptions, feelings, thoughts, and behaviors.
    • Hypnosis Theories
    • State Theory: Believes that hypnosis is actually altering a person’s state of consciousness. Freud believes this is a useful way to find and unlock or access the unconscious mind.
    • Role Theory (Social Influence Theory): Hypnosis is not an altered state of consciousness, rather that suggestible subjects are playing the role they believe the hypnotist wants them to play. They believe they are being hypnotized and it’s not intentional.
    • Dissociation Theory (Hidden Observer Theory): Hypnosis involves dissociation, a split in consciousness. Part of your mind is relaxed and open to suggestion while another part of your conscious mind is not altered by hypnosis. This is the hidden observer. This will not allow you to do something you would not normally do. This was created by Ernest Hilgard.
  • Posthypnotic Suggestion: Suggestion made during a session to alter behavior after hypnosis. This helps people to quit smoking, lose weight, and break addictions. It makes a negative connection.
    • Pain management or anesthesia.
    • Treatment of depression, anxiety, phobias, and some physical illness.
    • Relaxation.

Psychoactive Drugs

  • Any drug (prescription or recreational) that changes brain chemistry and alters your states of consciousness.
    • Depressants
    • Slows the pace of the central nervous system, creates a euphoric feeling, and inhibits brain function.
    • Alcohol
    • Benefits (In Moderation): Thin bloods, lowers risk of heart attack and stroke.
    • Risks (Medium To High Consumption): Damages dendrites, causing a loss of incoming signals, decreasing brain reaction, slurred speech, clumsiness, slow reflexes, and a loss of inhibition.
    • Barbiturates
    • Uses: Anesthesia/lethal injection, sleeping pills, and anticonvulsant for seizures.
    • Problems: Addictive and an overdose can cause a coma or death.
    • Anxiolytics/Tranquilizers: Used to treat anxiety (Valium and Xanax) but can be misused.
    • Stimulants
    • Speeds the pace of the central nervous system, heart rate, and respiration. It creates a euphoric feeling of self-confidence and invincibility. They increase anxiety, decrease sleep, and reduce appetite.
    • Caffeine: Found in coffee, tea, and chocolate. They increase alertness, wakefulness, and the ability to function. However, tolerance grows with consumption and it can be addictive.
    • Amphetamines/Benzedrine: Prescribed to treat ADD/ADHD, narcolepsy, and other sleeping disorders (Ritalin and Concerta).
    • Abuses: Students, athletes, or truck drivers may use it to increase mental and physical attention and stamina.
    • Side Effects: Dizziness, insomnia, aggression, addiction, depression, irregular heartbeat, and seizures.
    • Nicotine: Causes a mild euphoria (increased dopamine) and a calming sense. Increased levels of adrenaline and is highly addictive.
    • Cocaine: An extremely strong and addictive stimulant. The brain is flooded with dopamine causing the feeling of extreme pleasure and euphoria. The brain decreases dopamine production quickly. When the cocaine is gone, you become very unhappy/sick.
    • Crystal Meth: Interferes with brain chemistry of dopamine and norepinephrine, increases alertness, and is very addictive.
    • Hallucinogens
    • Also known as psychedelics, they change the perception of reality. They have no medical use.
    • Hallucinations: Experiencing a false sense (can be any of the five senses).
    • Delusion: Having a false belief.
    • LSD (Lysergic Acid Diethylamide): Also known as acid and has no medical use. It’s extremely potent (1/10 of a grain of sand would be an average dose). It can last from eight hours to a few days.
    • Psychotropic: Doesn’t create objects that are not real, but alters reality.
    • Problems: Trips can be bad, flashbacks can occur even years after (Hallucinogen Persisting Perception Disorder), and can cause psychosis which is a loss of reality (either temporary or long-term).
    • Peyote: A cactus plant that creates a deep and relaxed feeling of introspection; used as a ritual in some Native American tribes.
    • Marijuana/Cannabis: Can be classified in many drug categories and causes less control of motor and mental functions and a lack of concentration.
    • Dangers: It can be laced with other drugs (cocaine, PCP, LSD) without the knowledge of the user. Contains 50% to 70% more carcinogenic hydrocarbons than does tobacco smoke.
    • Opiates
    • Copies endorphins, acts as a powerful painkiller, extremely addictive, builds up a tolerance, and has drastic withdrawal symptoms.
    • Morphine: Used legally as a painkiller for serious illnesses, extremely addictive, causes confusion, sedation, euphoria, slow respiration, heart attack, coma, and death. Tolerance is developed very quickly and withdrawal is very difficult and extremely painful.
    • Heroin: Gives you an almost immediate high and causes euphoria and drowsiness. It’s the most addictive and dangerous drug with extremely painful and difficult withdrawal. It can cause death.

Unit 3: Sensation and Perception

  • Sensation: Experience stimulation from your senses (sight, hearing, touch, taste, smell).
  • Transduction: When a stimulus becomes a neurological message.
  • Sight
    • Visible Light: There are two factors of light.
    • Intensity: Determined by the wavelength’s height; influences brightness. A high wavelength equals bright color while a low wavelength equals dull color.
    • Hue: The distance from one wavelength to the next; determines color. Short wavelengths equal cool colors (bluish) while long wavelengths equal warm colors (reddish).
    • The Spectrum Of Visible Light
      The visible part of the spectrum may be further subdivided according to color, with red at the long wavelength end and violet at the short wavelength end, as illustrated in the following figure.
      How Light Travels Through The Eye
    • Cornea: Film covering that lets light enter the eye; helps focus the light.
    • Pupil: adjustable opening that lets light in; works like the lens of a camera.
    • Iris: Muscle that controls the pupil; dilates to let more light in the pupil and gets smaller to block light out.
    • Lens: Focuses the light and flips the image upside down.
    • Retina: Specialized neurons on which the image is projected. It’s divided into two halves (left and right). The messages from the left half goes to the left brain and the messages from the right goes to the right brain.
    • Optic Chiasm: Where the nerves cross over each other in the corpus callosum. Right half of the eye goes to the right brain, left goes to left.
    • Blind Spot: The area where the optic nerve joins the retina. There are no rods or cones in this area.
    • Feature Detectors: Activated by the retina, located in the occipital lobe. Group of neurons that differentiate between different images (vertical lines, curved lines, motion).
    • Rods And Cones: First cells activated by light; found in the retina. This is where transduction occurs. Rods respond to black and white, peripheral vision, and night vision. Cones respond to color.
    • Fovea: Center of the retina contains the largest amount of cones and only cones.
    • Bipolar Cells: Nerve cells that combine impulses from visual receptor cells in the retina and transmit them to ganglion cells.
    • Optic Nerve: Made up of ganglion cells and connects the eye to the brain.
    • Lateral Geniculate Nucleus (LGN): Specific part of the thalamus that receives visual information.
  • Color Vision Theories
    • Young-Helmholtz Trichromatic Color Theory: Three types of cones in the retina that detect blue, red, and green. These cones are combined to create all the colors on the spectrum. However, it does not explain color blindness or afterimaging.
    • Opponent-Process Theory: Cones are paired in the retina (red-green, yellow-blue, black-white). This theory does explain color blindness and afterimages.
    • Afterimages: When one of the pairs is fatigued, the other pair appears.
  • Color Blindness
    • Dichromatic Color Blindness: A person is either missing the red-green shades or blue-yellow shades.
    • Monochromatic Color Blindness: When people only see shades of gray.
    • Additive Color: When lights are blended, they turn white.
    • Subtractive Color Mixing: As colors are blended they become darker. Happens when mixing substances and not light.
    • Sound
    • Sound Waves: Vibrations that become neural messages and are sent to the brain.
    • Amplitude: Height of the wave; loudness of the sound.
    • Frequency: Length of the wave; determines the pitch.
  • The Ear
    • Ear Canal: The auditory canal; where the sound wave enters.
    • Eardrum: (Tympanic Membrane): Vibrates as sound hits it.
    • Hammer (Malleus), Anvil (Incus), Stirrup (Stapes): Three small bones that vibrate sound through the oval window.
    • Oval Window: Opening that sound waves travel through.
    • Cochlea: Filled with fluid that is moved when the oval window vibrates.
    • Basilar Membrane: A flexible structure in the cochlea covered with hair cells.
    • Organ Of Corti: Fires and sends neural messages to the brain.

Pitch Theories

  • Place Theory: Different pitches of sound move different hair cells in the cochlea.
  • Frequency Theory: Explains how lower tones are differentiated by the rates the nerves fire.

How Is Sound Located

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