Introductory Psychology: History, Research Methods, and Neuroscience

Vocabulary flashcards covering historical foundations, scientific methodology, research design, neural anatomy, action potential dynamics, and neurochemical transmission.

Psychology

The scientific study of the mind and behavior, derived from the Greek words psyche (soul) and logos (to study).

Mind

Private inner experiences including perceptions, thoughts, memories, feelings, and an ever-flowing stream of consciousness.

Behavior

Observable public actions of human beings and nonhuman animals.

Philosophical Dualism

The view articulated by Rene Descartes (1596-1650) that the body and mind (soul) are fundamentally different things, where the body is made of material substance and the mind is an immaterial spiritual substance ("Ghost in the machine").

Philosophical Materialism

The view proposed by Hobbes (1588-1679) that all mental phenomena are reducible to physical phenomena, meaning the mind is what the brain does.

Philosophical Realism

John Locke's (1632-1704) view that perceptions of the physical world are produced entirely by information from the sensory organs.

Philosophical Idealism

Immanuel Kant's (1724-1804) view that perceptions of the physical world are the brain's interpretation of information from sensory organs combined with existing information.

Philosophical Empiricism

Aristotle's view that all knowledge is acquired through experience, conceptualizing a newborn mind as a "Tabula Rosa" or blank slate.

Philosophical Nativism

Plato's view that some knowledge is innate rather than acquired through experience.

Structuralism

An approach to psychology that attempted to isolate and analyze the basic elements of the mind, breaking consciousness down into elements such as sensations and feelings.

Introspection

The method used in structuralism where trained observers analyze their own subjective experience and describe raw sensations, which proved to be invalid and unreliable.

Functionalism

The study of how mental processes enable people to adapt to their environments, focusing on the functions served by mental processes as inspired by Charles Darwin's principle of natural selection.

Hysteria

A loss of function that has no physical origin, studied by Jean Martin Charcot (1825-1893) and Pierre Janet (1859-1947).

Psychoanalytic Theory

Sigmund Freud's (1856-1939) approach emphasizing the importance of unconscious mental processes in shaping feelings, thoughts, and behaviors.

Unconscious

The part of the mind operating outside conscious awareness that influences conscious thoughts, feelings, and actions.

Behaviorism

An approach championed by John Broadus Watson (1878-1958) restricting scientific inquiry exclusively to observable behavior and stimulus-response relationships.

Skinner Box

An experimental apparatus (1904-1990) where an animal's action (such as a rat pressing a lever) produces a consequence like food, demonstrating how behavior is shaped by environment.

Principle of Reinforcement

B.F. Skinner's principle stating that any behavior that is rewarded will be repeated, and any behavior that is not rewarded will not be repeated.

Gestalt Psychology

A psychological approach pioneered by Max Wertheimer (1880-1943) emphasizing that humans often perceive the whole rather than the sum of its parts.

Developmental Psychology

The study of ways in which psychological phenomena change over the life span, famously investigated by Jean Piaget (1896-1980).

Social Psychology

A subfield pioneered by Kurt Lewin (1890-1947) asserting that behavior is a function of a person's subjective construal of their environment rather than stimulus alone.

Cognitive Psychology

The scientific study of human information processing (how we think, remember, and make decisions), inspired by computer analogies and championed by Noam Chomsky against behaviorism.

Evolutionary Psychology

The study of the ways in which the human mind has been shaped by natural selection, recognizing that organisms are biologically prepared to learn certain associations.

Cultural Psychology

The study of how cultures—defined as shared values, traditions, and beliefs—reflect and shape the psychological processes of their members.

American Psychological Association (APA)

An organization founded in 1892 when William James and six other psychologists met at Clark University.

Hindsight Bias

The tendency to believe, after learning an outcome, that one would have foreseen it

Critical Thinking

Analyzing, rather than simply accepting, information by examining flaws, discarding personal biases, searching for hidden assumptions, and considering alternative explanations.

Scientific Method

A procedure for finding facts using empirical evidence by developing a theory, deriving a falsifiable hypothesis, and gathering observational data.

Theory

A hypothetical explanation of a natural phenomenon using an integrated set of principles that organizes observations and predicts behaviors or events.

Hypothesis

A testable and falsifiable prediction made by a theory.

Operational Definition

A description of a property in concrete, measurable terms.

Construct Validity

The degree to which an operational definition adequately describes and measures the important feature of the phenomenon being studied.

Power

A measurement detector's ability to detect the presence of real differences or changes in the magnitude of a property.

Reliability

A measurement detector's ability to detect the absence of differences or produce identical results when measuring an unchanged property.

Demand Characteristics

Aspects of an observational setting that cause people to behave as someone else wants or expects them to behave.

Naturalistic Observation

A technique for gathering scientific information by unobtrusively observing people in their natural environments.

Observer Bias

The tendency for observers' expectations to influence both what they believe they observed and what they actually observed.

Double-Blind Study

An experimental procedure in which neither the participant nor the researcher collecting data knows how the participant is expected to behave or which group they are in.

Correlation

A measure of how closely two traits or variables vary together, or how well one variable predicts changes in another.

Correlation Coefficient

A statistical index ranging from $-1.00$ to $+1.00$ measuring the strength and direction of a relationship between two factors.

Scatterplot

A graphed cluster of dots representing two variables, where the slope of points indicates positive, negative, or lack of correlation.

Third Variable Problem

The fact that a natural correlation between two variables cannot prove a causal relationship because an unmeasured other variable might cause both.

Independent Variable

The factor in an experiment that is manipulated by the experimenter to study its causal effect.

Dependent Variable

The factor in an experiment that is measured to see if it changes when the independent variable is manipulated.

Confounding Variable

A factor other than the independent variable that might produce an effect in an experiment.

Random Assignment

A procedure that assigns participants to experimental or control conditions by chance to minimize pre-existing group differences.

Internal Validity

The extent to which an experiment provides solid evidence of cause-and-effect relationships without influence from confounding variables.

External Validity

The extent to which experimental results can be generalized to other contexts, populations, or real-world scenarios.

Neuron

Cells in the nervous system that communicate with each other to perform information-processing tasks; the human brain contains as many as $86\text{ billion}$

Dendrite

The branch-like part of a neuron that receives information from other neurons and relays it to the cell body.

Cell Body (Soma)

The part of a neuron that coordinates information-processing tasks and keeps the cell alive.

Axon

The part of a neuron that transmits information away from the cell body toward other neurons, muscles, or glands.

Myelin Sheath

An insulating layer of fatty material composed of glial cells that covers the axon to speed up impulse transmission.

Glial Cells

Support cells found throughout the nervous system that nourish and form myelin around neurons.

Node of Ranvier

The unmyelinated gap along an axon where voltage-gated ion channels are concentrated.

Terminal Buttons

Knoblike structures at the end region of an axon that branch out and store neurotransmitters inside vesicles.

Synapse

The junction or region between the terminal button of one neuron and the dendrites or cell body of another across which chemical signals pass.

Sensory Neurons

Neurons that receive information from the external world (light, sound, touch, taste, smell) and convey it to the brain via the spinal cord.

Motor Neurons

Neurons that carry signals from the spinal cord to the muscles to produce movement.

Interneurons

Neurons that connect sensory neurons, motor neurons, or other neurons within the nervous system.

Conduction

The movement of an electrical signal within a neuron from the dendrites and cell body down through the axon.

Transmission

The movement of electrical signals between neurons via chemical messengers crossing the synapse.

Resting Potential

The difference in electric charge inside relative to outside a neuron's membrane when at rest, measured at approximately $-70\,\text{mV}$.

Action Potential

An all-or-none electrical impulse conducted down a neuron's axon when the membrane potential reaches threshold (approx. $-55\,\text{mV}$), peaking around $+40\,\text{mV}$.

Depolarization

The initial phase of an action potential caused by voltage-gated sodium (\text{Na}^+) channels opening, allowing positive sodium ions to flow into the neuron.

Repolarization

The phase of an action potential where sodium (\text{Na}^+) channels become inactive and potassium (\text{K}^+) channels open, allowing positive potassium ions to rush out.

Hyperpolarization

The brief overshoot phase following an action potential where membrane potential drops lower than the resting potential.

Sodium-Potassium Pump

An active transporter protein in the neuronal membrane that restores resting ion balance by pumping $3\,\text{Na}^+$ ions out of the cell for every $2\,\text{K}^+$ ions brought in.

Saltatory Conduction

The rapid propagation of an action potential along a myelinated axon as the electrical impulse jumps from one Node of Ranvier to the next.

Excitatory Postsynaptic Potential (EPSP)

A depolarizing shift in postsynaptic potential that brings the membrane voltage closer to threshold, increasing the likelihood of an action potential.

Inhibitory Postsynaptic Potential (IPSP)

A hyperpolarizing shift in postsynaptic potential that moves the membrane voltage further from threshold, decreasing the likelihood of an action potential.

Neurotransmitters

Chemicals that transmit information across the synaptic gap from a presynaptic neuron's vesicles to a postsynaptic neuron's receptors.

Reuptake

The process by which excess neurotransmitters in the synaptic gap are absorbed back into the terminal buttons of the presynaptic neuron.

Acetylcholine (ACh)

A neurotransmitter involved in several functions including voluntary motor control.

Dopamine (DA)

A neurotransmitter regulating motor behavior, motivation, pleasure, and emotional arousal.

Glutamate

The major excitatory neurotransmitter in the brain involved in information transmission throughout the central nervous system.

GABA (gamma-aminobutyric acid)

The major inhibitory neurotransmitter in the brain.

Norepinephrine (NE)

A neurotransmitter particularly involved in states of vigilance or heightened awareness of environmental dangers.

Serotonin (5-HT)

A neurotransmitter involved in the regulation of sleep and wakefulness, eating, and aggressive behavior.

Endorphins

Chemicals that act within the pain pathways and emotion centers of the brain to dull pain and elevate mood.

Agonist

A drug or chemical that increases the action of a neurotransmitter or activates its receptor.

Antagonist

A drug or chemical that diminishes or blocks the function of a neurotransmitter.