Introductory Psychology: History, Research Methods, Biological Psychology, Sensation, Perception, and Learning

Comprehensive vocabulary flashcards reviewing historical foundations, scientific research methods, neuroanatomy, sensory processing, visual/auditory perception, and conditioning theories in introductory psychology.

Psychology

The scientific study of behavior (observable actions) and mind or mental processes/experience (thoughts, feelings, sensations, perceptions, motivations, and dreams).

Wilhelm Wundt

Recognized as the father of psychology; wrote the first psychology textbook in $1874$, established the first psychology research laboratory at the University of Leipzig, Germany in $1879$, and developed the method of introspection.

Introspection

A research method developed by Wilhelm Wundt involving the systematic examination of one's own conscious thoughts, feelings, and mental activities.

Structuralism

A school of thought led by Wilhelm Wundt and Edward Titchener that analyzes complex conscious experience by breaking it down into its simplest basic components, such as physical sensations and feelings, primarily through introspection.

Functionalism

A school of thought led by William James and influenced by Charles Darwin's theory of evolution that focuses on how behaviors and mental processes function to help an organism adapt to its environment.

Psychoanalysis

A therapeutic approach and theory developed by Sigmund Freud that focuses on bringing unconscious material—such as hidden conflicts, past childhood experiences, and repressed desires—into conscious awareness to understand psychological disorders.

Behaviorism

A psychological approach championed by John B. Watson and B.F. Skinner which argued that psychology should restrict itself to the scientific study of observable, measurable behavior rather than internal mental processes.

Margaret Floy Washburn

The first woman to earn a doctoral degree ($\text{Ph.D.}$) in psychology, author of extensive research on animal behavior, and a former president of the American Psychological Association (APA).

Humanistic Psychology

A perspective championed by Carl Rogers and Abraham Maslow emphasizing the positive potential of human beings, free will, choice, and personal growth, treating therapist and client on equal footing.

Cognitive Psychology

The scientific approach that emerged during the cognitive revolution of the late $1960\text{s}$ as a rebellion against behaviorism, focusing on how thoughts, memory, language, and problem solving are processed using the computer as a metaphor.

Gestalt Psychology

A psychological approach founded by Max Wertheimer which emphasizes that the mind tends to perceive unified wholes and complete configurations rather than merely the collection of individual separate parts.

Doll Study (Kenneth and Mamie Clark)

A landmark $1939$ research study presenting African American children with Black and White dolls to test the psychological effects of racial segregation; $66\%$ liked the white doll best and $59\%$ said the brown doll looked bad, findings later cited by the U.S. Supreme Court in Brown v. Board of Education ($1954$).

W.E.I.R.D. Cultures

An acronym standing for Western, Educated, Industrialized, Rich, and Democratic societies, which make up $96\%$ of psychology research subjects despite representing only $12\%$ of the global population.

Falsifiability

The essential property of a good scientific theory that makes specific, testable predictions capable of being proven false or refuted by observation and empirical research.

Operational Definition

A precise description of an abstract property or variable formulated in concrete, measurable terms to specify how it will be systematically detected and quantified in research.

Correlational Design

A research strategy that measures how closely two continuous variables vary together and determines how well changes in one variable predict changes in another, without manipulating variables.

Correlation Coefficient ($r$)

A statistical index ranging from $-1.0$ to $+1.0$ that measures the strength and direction of the linear relationship between two continuous variables.

Third-Variable Problem

A critical limitation of correlational research stating that an observed relationship between two variables may be caused by an unmeasured third factor rather than a direct causal link.

Independent Variable (IV)

The factor that an experimenter systematically manipulates or varies across conditions to determine its potential causal effect on an outcome.

Dependent Variable (DV)

The variable that is measured in an experiment and expected to change as a function of manipulations in the independent variable.

Random Assignment

The experimental procedure of placing participants into experimental conditions purely by chance, ensuring that individual differences (e.g., age, gender, IQ) are evenly distributed across groups.

Random Sampling

A research procedure where every member of a target population has an equal likelihood of being chosen to participate in a study, enhancing the generalization of findings.

Convenience Sample

A sample consisting of individuals who are readily and conveniently available to the researcher rather than being chosen randomly from the entire population.

Placebo Effect

A phenomenon in which participants experience measurable behavioral or physiological changes simply due to their expectations of receiving an active treatment, even when receiving an inactive substance.

Experimenter Bias

A source of error occurring when a researcher's expectations or hypotheses influence the outcome of a study by altering how they interact with participants or interpret ambiguous data.

Demand Characteristics

Cues in an experimental setting that lead participants to deduce the experimenter's hypothesis, causing them to alter their behavior subconsciously to match expectations.

Converging Operations

A methodological strategy that uses a variety of diverse research techniques and designs to investigate and converge upon a single theoretical conclusion.

Testing Effect

The robust empirical finding demonstrated by Roediger & Karpicke ($2006$) that actively practicing retrieval of information (practice testing) produces superior long-term memory retention after delays like $7\,\text{days}$ compared to passive restudying.

Cerebellum

A major structure located in the hindbrain responsible for fine motor coordination, balance, and motor control.

Medulla

A hindbrain structure directly continuous with the spinal cord that coordinates essential autonomic functions including heart rate, circulation, and respiration.

Reticular Formation

A network of neurons running inside the brainstem that regulates sleep, wakefulness, alertness, and levels of physiological arousal.

Pons

A hindbrain structure that acts as a bridge relaying information from the cerebellum to the rest of the brain.

Midbrain (Tectum and Tegmentum)

A central brain region containing the tectum and tegmentum that coordinates orientation responses to visual and auditory environmental stimuli.

Thalamus

A subcortical forebrain structure that acts as a sensory relay station, filtering and transmitting incoming sensory signals (except smell) to the cerebral cortex.

Hypothalamus

A subcortical forebrain structure located beneath the thalamus that regulates body temperature, hunger, thirst, and the four F's (fighting, fleeing, feeding, and mating).

Amygdala

A subcortical forebrain structure located at the tip of each horn of the hippocampus that plays a central role in processing emotional memories and emotional responses, particularly fear.

Hippocampus

A subcortical forebrain structure critical for creating, consolidating, and integrating new long-term memories into the cerebral cortex, as illustrated by patients H.M. and Clive Wearing.

Basal Ganglia

A set of subcortical forebrain structures that directs intentional body movements and plays an integral role in processing rewards.

Cerebral Lobes

The four distinct anatomical divisions of the cerebral cortex: the frontal lobe (executive function/motor control), parietal lobe (somatosensory processing), occipital lobe (vision), and temporal lobe (hearing/language).

Somatosensory Cortex

A strip of tissue located in the anterior parietal lobe that maps body sensations, wherein more sensitive body areas (like fingers and lips) are allocated larger cortical surface areas.

Motor Cortex

A strip of tissue located in the posterior region of the frontal lobe that initiates voluntary muscle movements, with cortical representations weighted proportionally to precision and importance.

Broca's Area

A language center located in the left frontal lobe responsible for speech production; damage causes halting, non-fluent speech with grammatical impairment but intact comprehension.

Wernicke's Area

A language region situated in the left temporal lobe responsible for speech comprehension; damage results in fluent but meaningless speech with severe comprehension deficits.

Corpus Callosum

The large band of neural fibers connecting the left and right cerebral hemispheres, which when surgically severed produces split-brain syndrome.

Split-Brain Syndrome

A neurological condition resulting from surgical resection of the corpus callosum, isolating hemispheric processing such that visual stimuli presented to the left visual field (right hemisphere) can be drawn with the left hand but cannot be verbally named by the language-dominant left hemisphere.

Neuron

A specialized cell in the nervous system that processes and transmits information through electrical and chemical signals.

Dendrites

Branch-like extensions of the neuron that receive incoming biochemical messages from adjacent neurons and relay them to the cell body.

Axon

The elongated extension of a neuron that conducts electrical impulses away from the cell body toward terminal branches and adjacent neurons.

Myelin Sheath

An insulating layer of fatty material formed by glial cells surrounding the axon, which dramatically increases the speed and efficiency of neural impulse transmission.

Resting Potential

The baseline electrical charge difference across a dormant neuron's membrane ($-70\,\text{mV}$), maintained by a high concentration of sodium ions ($\text{Na}^+$) outside and potassium ions ($\text{K}^+$) and protein anions inside.

Action Potential

An all-or-none electrical impulse that travels down the entire length of an axon when membrane stimulation reaches the excitation threshold of $-55\,\text{mV}$.

Depolarization

The rapid initial phase of an action potential during which voltage-gated sodium channels open and positive sodium ions ($\text{Na}^+$) rush into the cell interior, shifting the membrane potential from negative to positive.

Repolarization

The recovery phase of an action potential during which sodium channels close and potassium channels open, allowing potassium ions ($\text{K}^+$) to exit the cell and restore the internal negative charge.

Summation of Postsynaptic Potentials

The additive integration of excitatory postsynaptic potentials (EPSPs) and inhibitory postsynaptic potentials (IPSPs) at the axon hillock to determine whether the $-55\,\text{mV}$ threshold is reached to initiate an action potential.

Acetylcholine (ACh)

A major neurotransmitter involved in multiple cognitive and physical functions, notably the activation of muscle contractions for voluntary motor control.

Dopamine

A neurotransmitter that regulates motor behavior, pleasure, emotional arousal, and motivation; its loss in specific pathways is linked to Parkinson's disease.

Agonist

A drug or chemical substance that binds to a neurotransmitter's receptor and enhances or mimics the action of that neurotransmitter.

Antagonist

A drug or chemical compound (such as Botox, which blocks acetylcholine release) that blocks receptor sites or inhibits neurotransmitter activity.

Functional Magnetic Resonance Imaging (fMRI)

A brain-imaging technique that maps ongoing neural activity by detecting regional changes in blood oxygenation levels, offering high spatial resolution but poor temporal resolution.

Electroencephalography (EEG)

A direct measure of electrical brain activity recorded from electrodes placed on the scalp, offering millisecond-level temporal resolution but low spatial resolution.

Sensation

The physical acquisition and initial processing of environmental stimuli by peripheral sense organs.

Perception

The psychological process of organizing, identifying, and interpreting sensory information in order to form a meaningful mental representation of the environment.

Transduction

The fundamental sensory process in which specialized receptor cells convert physical environmental energies (light waves, sound vibrations) into neural electrical impulses.

Psychophysics

The systematic study pioneered by Gustav Fechner that quantifies the relationship between physical stimulus intensities and the psychological sensory perceptions they produce.

Absolute Threshold

The minimal intensity of physical stimulation required for a sensory organ to detect a stimulus on exactly $50\%$ of presentation trials.

Just Noticeable Difference (JND)

The minimum quantitative difference between two stimuli necessary for an observer to distinguish between them $50\%$ of the time.

Top-Down Processing

Perceptual processing driven by an individual's prior knowledge, expectations, experiences, and contextual interpretations.

Bottom-Up Processing

Perceptual processing that begins with the analysis of raw, discrete sensory details, assembling them to build a comprehensive higher-level mental image.

Signal Detection Theory

A perceptual framework stating that detecting a faint stimulus depends not only on physical sensory sensitivity but also on psychological decision criteria (expectations, motivation, fatigue), yielding hits, misses, false alarms, and correct rejections.

Sensory Adaptation

The reduction in sensory receptor responsiveness that occurs after prolonged, unchanging exposure to a constant environmental stimulus.

Inattentional Blindness

A failure to consciously perceive unexpected visible objects within the visual field when visual attention is focused entirely on another task.

Change Blindness

The inability of an observer to detect noticeable alterations to visual details in a visual scene across brief interruptions or saccades.

Cones

Approximately $6\,\text{million}$ specialized retinal photoreceptors concentrated predominantly in the fovea, responsible for sharp visual acuity and daytime color perception.

Rods

Approximately $120\,\text{million}$ peripheral retinal photoreceptors sensitive to dim light and motion, which do not process color or fine detail.

Fovea

The central focal region of the retina containing an exclusive concentration of cones, providing maximal spatial resolution and visual detail.

Trichromatic Color Theory

The theory of color vision stating that color perception results from the differential activation of three distinct types of cones sensitive to short (blue), medium (green), and long (red) wavelengths of light.

Color Blindness (Ishihara Test)

A visual deficit in distinguishing certain colors, typically resulting from the absence or dysfunction of one or more cone types in the retina, diagnosed using pseudoisochromatic plates.

Opponent-Process Theory

Ewald Hering's theory stating that pairs of opposing visual neurons (red/green, blue/yellow, black/white) process color signals at the level of ganglion cells, LGN, and cortex, explaining negative afterimages via rebound neural firing.

Feature Detectors

Specialized neurons discovered by Hubel and Wiesel in the primary visual cortex (V1) that fire selectively in response to specific characteristics of a visual stimulus, such as lines, edges, and orientations.

Ventral Pathway

The 'what pathway' of visual processing traveling from the primary visual cortex to the temporal lobe, dedicated to identifying object identity, shapes, and faces.

Dorsal Pathway

The 'where pathway' of visual processing originating in V1 and extending to the parietal lobe, responsible for computing spatial location, motion, and guiding motor actions toward objects.

Visual Agnosia

A neurological condition resulting from damage to the ventral stream characterized by the complete inability to recognize objects by sight despite intact basic vision.

Prosopagnosia

A category-specific visual deficit resulting from ventral stream damage that impairs the ability to recognize familiar human faces while leaving general object recognition preserved.

Retinal Disparity

A binocular depth cue arising from the slightly different spatial viewpoints of the two eyes, which project two disparately positioned images onto the retinas.

Brightness Constancy (Checker Shadow Illusion)

The perceptual constancy wherein the perceived lightness of a surface remains constant under varying illumination; in Adelson's illusion, tile A and tile B have identical physical luminance but appear different due to shadow context.

McGurk Effect

A multimodal perceptual illusion demonstrating that visual speech information (lip movements) directly integrates with and alters conflicting auditory input, creating a third distinct perceived phoneme.

Synaesthesia

A neurological condition in which stimulation in one sensory or cognitive pathway leads to involuntary, automatic experiences in a second, unrelated sensory pathway (such as hearing music and seeing colors).

Learning

An experience that results in a relatively permanent change in the state of the learner.

Classical Conditioning

A form of associative learning first discovered by Ivan Pavlov in $1906$ in which an organism learns to associate a previously neutral stimulus with an unconditioned stimulus, eliciting an involuntary reflex.

Unconditioned Stimulus (US)

A stimulus that naturally, reliably, and automatically elicits a physiological reflex or unconditioned response without any prior learning (e.g., food in Pavlov's experiment).

Unconditioned Response (UR)

An unlearned, automatic reflexive reaction elicited by an unconditioned stimulus (e.g., salivation upon seeing or smelling food).

Conditioned Stimulus (CS)

A previously neutral stimulus that, through repeated pairings with an unconditioned stimulus, acquires the ability to elicit a learned conditioned response (e.g., the bell tone).

Conditioned Response (CR)

A learned response elicited by a conditioned stimulus after acquisition has occurred, which resembles the unconditioned response but is triggered by the conditioned stimulus.

Acquisition

The initial learning phase in classical conditioning during which a neutral stimulus is repeatedly paired with an unconditioned stimulus until the conditioned response is firmly established.

Extinction (Classical Conditioning)

The gradual weakening and disappearance of a conditioned response when the conditioned stimulus is repeatedly presented in the absence of the unconditioned stimulus.

Spontaneous Recovery

The sudden reappearance of an extinguished conditioned response following a period of rest without any further conditioning pairings.

Stimulus Generalization

The tendency of stimuli that are physically similar to the original conditioned stimulus to elicit the same conditioned response.

Stimulus Discrimination

The learned capacity of an organism to differentiate between a conditioned stimulus and other distinct stimuli, restricting the response to the target stimulus.

Preparedness

The evolutionary predisposition of an organism to learn certain survival-relevant associations far more easily and rapidly than others.

Conditioned Taste Aversion

A specialized form of classical conditioning that occurs after a single pairing of a ingested food with subsequent nausea, developing even across delays of several hours.