Introduction to Psychology: Foundations, Methods, Evolution, and Neurobiology

Comprehensive vocabulary flashcards covering the introductory history, scientific methodology, ethics, statistics, evolutionary psychology, and neuroanatomy of Psychology A01.

Cartesian Dualism

The philosophical doctrine introduced by René Descartes (1596–1650) proposing that the human physical body functions as a mechanical machine controlled by an immaterial, non-physical soul.

Animism

The pre-scientific belief that natural events, objects, and inanimate forces (such as falling rocks and volcanoes) possess conscious spirits, souls, or intentional agency.

Tabula Rasa

The empiricist concept emphasized by John Locke (1632–1704) asserting that the human mind begins as a blank slate at birth and all knowledge develops from sensory experience.

Materialism

The philosophical position advocated by thinkers like James Mill (1773–1836) holding that the mind is entirely physical and operates as a biological machine governed by natural laws.

Doctrine of Specific Nerve Energies

The physiological principle formulated by Johannes Müller (1801–1858) stating that the nature of a sensory perception is determined by the specific neural pathway that is stimulated rather than by the physical nature of the stimulus itself.

Ablation Studies

An experimental physiological technique pioneered by Pierre Flourens (1774–1867) involving the surgical removal or destruction of specific brain regions in animals to determine their function by observing subsequent behavioral deficits.

Localization of Function

The discovery exemplified by Paul Broca (1824–1880) showing that discrete cognitive and behavioral capacities, such as speech production, are localized to specific, identifiable brain regions.

Weber Fraction

A psychophysical formula formulated as $\frac{\Delta I}{I} = K$, which demonstrates that the just noticeable difference ($\Delta I$) between stimuli is a constant proportion ($K$) of the original stimulus intensity ($I$).

Structuralism

The early school of psychology founded by Wilhelm Wundt (1832–1920) that sought to break down conscious experiences into their basic building blocks and structural components using experimental introspection.

Apprehension

In Wilhelm Wundt's model of consciousness, the initial, wide, and variable process through which sensory content simply enters conscious awareness prior to focused attention.

Apperception

In Wilhelm Wundt's model of consciousness, the active, constant, and capacity-limited process of focusing conscious attention onto specific apprehended elements.

Functionalism

An early psychological approach led by William James (1842–1910) and inspired by Charles Darwin that examined the practical purpose and adaptive survival function of mental processes rather than their structural components.

Ebbinghaus Forgetting Curve

A mathematical curve of memory retention over time established by Hermann von Ebbinghaus (1850–1909), showing that learned material is forgotten rapidly within minutes and hours before retention stabilizes over days and weeks.

Gestalt Psychology

A European school of psychology that investigated the perceptual rules and organizational laws by which humans integrate sensory noise to perceive unified, stable wholes rather than isolated components.

Behaviorism

A North American movement championed by Ivan Pavlov, John B. Watson, and B.F. Skinner that rejected subjective mental events and focused exclusively on the objective study of observable stimuli and behavioral responses.

Cognitive Revolution

The mid-20th-century intellectual movement that shifted psychology back toward the scientific study of internal mental operations, heavily influenced by analogies to computers and electronic information processing systems.

Post-Truth

A term denoting cultural or political circumstances in which objective facts have less influence in shaping public belief and opinions than emotional appeals and pre-existing personal convictions.

Hawthorne Effect

The alteration or improvement in behavior shown by research participants solely due to their awareness of being observed and evaluated.

Correlation

A statistical measure expressing the degree of relationship between two variables, classified as positive (both increase together), negative (one increases as the other decreases), or zero (no systematic pattern).

Third Variable Problem

The circumstance in correlational research where an unmeasured, external variable is responsible for producing the observed statistical association between two variables, precluding causal conclusions.

Operational Definition

The explicit, objective specification of how an experimental variable is manipulated or measured within a given scientific study.

Internal Validity

The degree to which an experimental design is methodologically sound, adequately controlled, and free from confounding variables, ensuring the independent variable caused the change in the dependent variable.

Institutional Review Board (IRB)

An independent ethical review committee that examines research protocols involving human participants to guarantee adherence to ethical principles including informed consent, debriefing, and risk minimization.

The Three R's in Animal Testing

Ethical principles formulated by Russell and R.L. Burch (1959) guiding the treatment of animals in research: Replacement (using non-animal alternatives), Reduction (using statistical methods to require fewer animals), and Refinement (improving procedures to eliminate suffering).

Speciesism

The assumption of human moral superiority leading to the systematic exploitation and devaluation of the rights, interests, and welfare of non-human animals.

Descriptive Statistics

Mathematical procedures used to summarize, organize, and describe the characteristics of a specific observed sample, including measures of central tendency and spread.

Inferential Statistics

Statistical methods (such as $t$-tests and correlation coefficients) that use sample data to draw probabilistic generalizations and conclusions about a broader population.

Standard Deviation

A measure of variability that quantifies the typical or standard distance that individual scores in a dataset deviate from the mean of the distribution.

t-Test

An inferential statistical test utilized to determine whether the difference between the means of two distinct experimental or observational groups is statistically significant.

Confound

An uncontrolled, extraneous variable in an experiment that co-varies with the independent variable, offering an alternative explanation for the observed findings.

Genetic Drift

A mechanism of evolution involving random fluctuations in allele frequencies within a small population due to chance events, deaths, or reproductive failures.

Social Complexity Hypothesis

The evolutionary theory proposing that the evolution of larger, highly intelligent human brains was driven primarily by the demands of complex social interaction, communication, and cooperation rather than ecological challenges.

Epigenetics

The study of environmental influences that alter gene expression and cellular phenotype by modifying chemical marks on the epigenome without changing the underlying DNA sequence.

Monozygotic Twins

Identical twins developed from a single egg fertilized by a single sperm that splits into two embryos, resulting in individuals who share $100\%$ of their genetic material.

Human Estrus

The cyclic phase of peak female fertility and sexual receptivity; economic evidence showed naturally cycling lap dancers earned significantly higher tips ($\$335$ per shift) during estrus than during luteal ($\$260$) or menstrual ($\$185$) phases.

Reciprocal Altruism

An evolutionary behavior whereby an individual provides a beneficial act to an unrelated individual at a personal cost, under the adaptive expectation that the assistance will be returned later.

Autonomic Nervous System

The division of the peripheral nervous system responsible for regulating involuntary, visceral bodily functions, consisting of the sympathetic and parasympathetic branches.

Sympathetic Nervous System

The fight-or-flight division of the autonomic nervous system that dilates pupils, inhibits salivation and digestion, accelerates heart rate, and causes peripheral vasoconstriction.

Parasympathetic Nervous System

The rest-and-digest division of the autonomic nervous system that constricts pupils, stimulates salivation and digestion, slows heart rate, and promotes peripheral vasodilation.

Transorbital Lobotomy

A psychosurgical procedure popularized by Walter Freeman in which an orbitoclast instrument is hammered through the eye socket into the prefrontal cortex to sever nerve fibers connecting the frontal lobes to the diencephalon.

Premotor Cortex

A cortical region situated anterior to the primary motor area that controls complex movements, coordinates reaching and grasping, maintains posture, and participates in decision-making.

Somatosensory Homunculus

A neurological map of the body across the primary somatosensory and motor cortices showing proportional cortical representation, where sensitive areas like hands, lips, and tongue occupy disproportionately large areas.

Perseveration Error

A persistent cognitive symptom of prefrontal cortical damage wherein an individual is unable to shift rules or strategies, continually repeating a previously reinforced response despite negative feedback.

Limbic System

A group of interconnected subcortical and cortical structures—including the hippocampus, amygdala, hypothalamus, and cingulate gyrus—responsible for regulating emotion, motivation, learning, and memory.

Cerebral Cortex

The folded, outer layer of gray matter of the brain responsible for high-level sensory perception, voluntary motor planning, conscious deliberation, and flexible cognition.

Contralateral Organization

The neuroanatomical arrangement whereby sensory inputs and voluntary motor outputs of each side of the body or external space are represented and processed by the opposite cerebral hemisphere.

Scotoma

A distinct blind spot or hole within an individual's visual field caused by localized physical damage to the primary visual cortex in the occipital lobe.

Visual Agnosia

A perceptual impairment caused by damage to the visual association cortex where a person can see objects normally but loses the ability to recognize or name them.

Proprioception

The continuous sensory perception and spatial awareness of body position and limb location, primarily processed by the association areas of the left parietal lobe.