HDE 100C: Human Development and Aging Exam Review

A comprehensive vocabulary review of developmental, biological, sensory, neural, cognitive, and psychosocial aspects of aging based on HDE 100C lecture modules.

Chronological Age

Age defined strictly by birthdate, representing the total number of years an individual has lived on the planet.

Biological Age

An estimate of how many years a person is expected to have left to live, based on physiological and organ-system assessments.

Psychological Age

An individual's functional capacity to adapt to, manage, and cope with life circumstances and environmental demands relative to developmental norms.

Social Age

Age evaluated by comparing an individual's expected social roles, habits, and behaviors to the prevailing societal norms across the life course.

Lifespan Perspective vs. Life Course Perspective

The lifespan perspective examines the total number of years an individual lives, whereas the life course perspective emphasizes the meaningful patterns, roles, transitions, and cultural rites of passage across those years.

Lifespan Developmental Theory (Baltes)

A developmental framework proposing that development is lifelong, multidimensional, multidirectional, plastic, historically situated, and shaped by shifting biological and cultural dynamics.

Multidirectionality

A principle of lifespan development stating that development involves simultaneous growth and decline across different domains at varying rates.

Plasticity

The developmental principle that cognitive and physical capacity is not fixed, meaning skills and faculties can be trained, altered, or improved through intervention even in late adulthood.

Age-Normative Influences

Biological, psychological, and sociocultural experiences tied strongly to chronological age that occur at roughly the same point for most individuals, such as puberty, menopause, and retirement.

History-Normative Influences

Broad historical events or cultural shifts experienced simultaneously by most members of a given population, such as the September 11 attacks or the COVID-19 pandemic.

Non-Normative Influences

Random, unpredictable, or idiosyncratic life events that happen to a specific individual rather than a whole cohort, such as winning the lottery or receiving a cancer diagnosis.

Selective Optimization with Compensation (SOC) Model

A meta-theory of successful aging wherein individuals select fewer life domains (selection), dedicate resources to maximize skills in those domains (optimization), and employ internal or external alternatives to manage functional losses (compensation).

Model of Ecological Systems

A contextual framework conceptualizing development within nested systems: Microsystem (immediate settings), Mesosystem (interconnections among settings), Exosystem (indirect environments), Macrosystem (cultural values and ideologies), and Chronosystem (temporal changes).

Continuity vs. Discontinuity

A foundational issue in developmental psychology questioning whether aging progresses as a smooth, gradual quantitative accumulation of changes (continuity) or through distinct, qualitative, abrupt stages (discontinuity).

Universal vs. Context-Specific Development

The debate over whether developmental trajectories follow a single fundamental pathway common to all human beings or multiple distinct pathways dictated by environment, life events, and culture.

Cohort

A group of individuals who share a particular experience or were born within the same specific historical time period (e.g., individuals born in 1950).

Cross-Sectional Study

A research design assessing multiple age groups at a single point in time, offering efficiency and lower cost but confounding true age-related changes with generational cohort differences.

Longitudinal Study

A research design that repeatedly tracks and tests the same individuals over extended periods, measuring true age changes but vulnerable to high cost, selective attrition, and retest practice effects.

Sequential Design

A developmental research methodology combining cross-sectional and longitudinal approaches across multiple cohorts to isolate and disentangle the effects of chronological age, birth cohort, and time of measurement.

Primary Aging

Inherent, genetically driven, universal, and irreversible biological processes of senescence that occur across all members of a species over time.

Secondary Aging

Non-universal, variable developmental declines caused by environmental trauma, disease pathology, abusive lifestyle habits, or chronic disuse, which may be preventable or reversible.

Wear-and-Tear Theory

An error theory of biological aging proposing that mechanical use, environmental stress, and accumulated physical damage steadily exhaust cellular and tissue vitality over time.

Lipofuscin

A yellow-brown to dark brown metabolic waste pigment that accumulates progressively inside postmitotic cells (such as neurons and cardiac myocytes), interfering with cellular transport, signaling, and metabolism.

Free Radical Theory

A biological theory stating that aging results from cellular damage inflicted by reactive oxygen species (ROS) with an unpaired electron, causing oxidative stress that destabilizes DNA, lipids, and proteins.

Antioxidants

Chemical molecules that inhibit oxidation by neutralizing free radicals, thereby protecting cellular structures from reactive oxygen species damage.

Time-Clock Theory (Hayflick Limit)

A programmed theory of aging asserting that normal human cells possess an internal biological limit on how many times they can divide before entering replicative senescence.

Telomere Theory

A genetic aging model establishing that repetitive non-coding DNA end caps (telomeres) shorten with each round of cell division, eventually rendering cells unable to replicate.

Cellular Senescence

A permanent cessation of cell division in response to stress or telomere depletion, causing cells to survive in a non-replicating state and secrete pro-inflammatory factors.

Apoptosis

Programmed cell death that functions as a cellular suicide mechanism to eliminate damaged, senescent, or potentially dangerous mutated cells.

APOE Gene (Apolipoprotein E)

A gene on chromosome 19 involved in lipid transport whose variants modify Alzheimer's disease risk: the $\text{ε}4$ allele increases risk, whereas the $\text{ε}2$ allele decreases risk.

Brain-Derived Neurotrophic Factor (BDNF)

A neurotrophin that promotes the survival, differentiation, and maintenance of neurons while enhancing synaptic plasticity and memory mechanisms in the hippocampus.

Synaptic Plasticity

The capacity of communication junctions between neurons (synapses) to strengthen, reorganize, or weaken over time in response to learning, activity, and environmental demands.

Epigenome

The array of chemical modifications (such as DNA methylation and histone modifications) that control chromatin architecture and gene expression without altering the genetic sequence.

Caloric Restriction

The reduction of dietary caloric intake without malnutrition, which lowers metabolic rate and oxidative damage, consistently extending lifespan and reducing age-related disease in experimental animal models.

Sarcopenia

The progressive, age-associated involuntary loss of skeletal muscle mass, contractile strength, and physical performance occurring in late adulthood.

Osteoporosis

A skeletal disorder characterized by marked bone demineralization and microarchitectural deterioration that accounts for over 70% of fractures in older adults, disproportionately affecting postmenopausal women.

Osteoarthritis (OA)

A localized, non-autoimmune degenerative joint disorder caused by cumulative mechanical wear-and-tear leading to the progressive breakdown and thinning of articular cartilage.

Rheumatoid Arthritis (RA)

A systemic autoimmune disorder in which the immune system mounts a symmetrical attack on the synovial membranes of joints, triggering chronic inflammation and systemic damage.

Congestive Heart Failure

A cardiovascular condition where impaired cardiac pumping fails to supply adequate blood to organs, causing systemic fluid congestion that manifests as peripheral edema and pulmonary swelling.

Cerebral Arteriosclerosis

Hardening, loss of elasticity, and luminal narrowing of cerebral arteries due to lipid plaque deposition and calcification, elevating the risk of ischemic and hemorrhagic strokes.

Cataracts

A visual disorder resulting from progressive clouding, thickening, and yellowing of the eye's crystalline lens, causing generalized visual blurriness and glare.

Age-Related Macular Degeneration (AMD)

A visual pathology caused by deterioration of the macula within the retina, leading to severe blurriness, distortion, or complete loss of central vision while sparing peripheral fields.

Glaucoma

An ocular disorder characterized by poor fluid drainage that elevates intraocular pressure, damaging the optic nerve and producing characteristic tunnel vision or loss of peripheral vision.

Diabetic Retinopathy

A retinal microvascular complication of diabetes in which fragile, damaged capillary vessels leak blood and fluid into the retina, causing visual impairment.

Conductive Hearing Loss

Auditory impairment caused by mechanical or physical blockage that obstructs sound waves traveling through the outer ear canal, tympanic membrane, or ossicles of the middle ear.

Sensorineural Hearing Loss

Auditory impairment resulting from damage to sensory hair cells inside the inner ear cochlea or along the cranial auditory nerve pathways.

Presbycusis

Age-related sensorineural hearing loss marked by a bilateral loss in detecting high-frequency tones, typically caused by hair cell deterioration in the basal turn of the cochlea.

Diffusion Tensor Imaging (DTI)

An advanced magnetic resonance neuroimaging technique that tracks the directional diffusion of water molecules along myelinated white matter tracts to evaluate structural connectivity.

Resting-State Functional Connectivity (rs-fMRI)

A neuroimaging method measuring spontaneous, low-frequency blood-oxygen-level-dependent (BOLD) signal correlations across spatially distinct brain regions while the subject rests without an explicit task.

Frontal Lobe Hypothesis

The neurobiological framework stating that prefrontal cortex structures and networks deteriorate earlier and more severely with age, driving selective declines in executive function and working memory.

Processing Speed Theory (Salthouse)

A cognitive aging theory stating that reduced nervous system processing speed causes cognitive decline through two mechanisms: the limited-time mechanism and the simultaneity mechanism.

Common Cause Hypothesis

A theory proposing that concurrent sensory declines (vision, hearing) and cognitive declines during aging do not cause each other, but rather reflect a shared underlying systemic biological aging process.

Information Degradation Hypothesis

A sensory aging hypothesis stating that impoverished, poor-quality sensory inputs immediately overwhelm and compromise higher-order cognitive processing and task accuracy.

Sensory Deprivation Hypothesis

The hypothesis proposing that chronic, prolonged reductions in sensory stimulation gradually erode neural circuits and cause cognitive decline over extended time periods due to reduced engagement.

Inhibitory Theory

A cognitive aging model proposing that age-related deficits in attention and memory stem from an impaired ability to suppress goal-irrelevant stimuli and ignore distracting information.

Crystallized Cognition

The store of accumulated cultural knowledge, facts, semantic skills, and vocabulary acquired through lifelong experience, which remains stable or improves across older adulthood.

Fluid Cognition

The basic mechanics of information processing, abstract reasoning, novel pattern solving, and spatial manipulation, which peaks in early adulthood and undergoes steady age-related decline.

Working Memory

A limited-capacity, active cognitive memory system that temporarily maintains and transforms information to execute complex mental operations, guided by a Central Executive and slave systems.

Hippocampus

A medial temporal lobe structure essential for memory consolidation, episodic encoding, and spatial navigation that exhibits significant structural shrinkage with age.

Episodic Memory

The conscious, explicit recollection of personally experienced events situated in a specific spatial and temporal context, characterized by subjective autonoetic awareness.

Semantic Memory

The conscious, explicit retrieval of general factual knowledge, concepts, and objective rules about the world, associated with noetic awareness rather than personal temporal context.

Procedural Memory

An implicit, non-conscious long-term memory system mediated primarily by the basal ganglia that automates motor routines, perceptual-motor skills, and behavioral habits.

Priming

An implicit memory phenomenon in which prior subconscious exposure to a specific stimulus, word, or cue facilitates the subsequent recognition or identification of related information.

Posterior-Anterior Shift in Aging (PASA) Model

A neurofunctional compensation pattern wherein older adults display reduced posterior sensory activations (occipital/temporal) paired with increased anterior activations (prefrontal) to preserve task performance.

HAROLD Model

Hemispheric Asymmetry Reduction in OLDer adults; a model describing how prefrontal cortical activity becomes less lateralized and more bilateral in high-performing older adults to recruit neural support.

CRUNCH Model

Compensation-Related Utilization of Neural Circuits Hypothesis; posits that older brains over-recruit neural regions at low cognitive demands to maintain performance, but hit an exhaustion ceiling at high task difficulty.

STAC-r Model

Scaffolding Theory of Cognitive Aging-revised; a neuroplasticity framework postulating that brains construct complementary scaffolding circuits to offset biological and functional degradation.

Socioemotional Selectivity Theory (SST)

A motivational lifespan theory stating that as people perceive their remaining time horizons as shrinking, they intentionally narrow social networks to prioritize emotionally meaningful relationships over informational goals.

Social Convoy Model

A conceptual model describing how an evolving, protective convoy of supportive social connections accompanies and buffers an individual across the life course.

Chronological Age

The measure of age based strictly on an individual's calendar birthdate and the elapsed time lived in years.

Biological Age

A measurement of physiological status and remaining life expectancy based on biological, organ-system, and cellular assessments rather than calendar years.

Psychological Age

The capacity of an individual to adapt, cope with life circumstances, and handle environmental and behavioral demands relative to developmental stages.

Social Age

A measure of age based on an individual's enacted roles, habits, and social positions relative to the expectations and norms of their society and culture.

Lifespan Perspective vs. Life Course Perspective

The lifespan perspective examines development as total years lived across the biological lifespan, whereas the life course perspective emphasizes meaningful social transitions, trajectories, historical contexts, and role changes over those years.

Baltes' Lifespan Developmental Theory

A developmental framework proposing that development is lifelong, multidimensional, multidirectional, characterized by plasticity, historically situated, and shaped by shifting biological and cultural forces across the entire life course.

Multidirectionality

The developmental principle stating that development involves concurrent gains and losses across domains, such that growth in one area may occur alongside decline in another at different rates.

Age-Normative Influences

Biological or environmental events strongly tied to chronological age that typically happen to most individuals in a given population around the same life period, such as puberty, menopause, and retirement.

History-Normative Influences

Historical events and cultural shifts shared by a broad demographic at a specific point in time that shape developmental trajectories, such as the 9/11 attacks or the COVID-19 pandemic.

Non-Normative Influences

Unpredictable, idiosyncratic events that occur to specific individuals rather than entire cohorts or age groups, such as winning the lottery or receiving a cancer diagnosis.

Selective Optimization with Compensation (SOC) Model

A meta-theory for successful aging where individuals select fewer goal domains, optimize abilities through practice and skill enhancement, and compensate using internal or external strategies to maintain performance despite losses.

Ecological-Systems Model

Bronfenbrenner's systems-based framework showing human development embedded across reciprocal, nested contextual levels: individual, microsystem, mesosystem, exosystem, macrosystem, and chronosystem.

Continuity vs. Discontinuity

A core developmental issue concerning whether age-related change proceeds as a smooth, cumulative progression over time (continuity) or as a succession of abrupt, qualitatively distinct stages (discontinuity).

Cohort

A group of individuals who share a common historical experience or birth period within a defined temporal window (e.g., individuals born in 1950).

Cross-Sectional Study Design

A research design that assesses different age cohorts simultaneously at a single point in time to examine age differences, which confounds true developmental age effects with cohort differences.

Longitudinal Study Design

A research methodology tracking the exact same individuals repeatedly over an extended duration to measure intra-individual developmental change directly, though vulnerable to attrition, practice effects, and time-of-measurement confounds.

Sequential Study Design

A research approach that integrates cross-sectional and longitudinal elements across multiple cohorts tested across successive intervals to disentangle age, cohort, and time-of-measurement effects.

Primary Aging

Genetically regulated, intrinsic biological changes that are universal, inevitable, and irreversible across all members of a species, occurring independently of disease or lifestyle.

Secondary Aging

Age-associated decline attributable to non-universal external factors, pathology, environmental hazards, sedentary lifestyles, abuse, or disuse, which may be preventable or modifiable.

Basal Metabolic Rate (BMR) and Lifespan

An ecological principle describing an inverse relationship where larger organisms typically have lower metabolic rates per unit mass and longer maximum species lifespans.

Wear-and-Tear Theory

An error-based biological theory stating that cumulative physical, environmental, and mechanical stresses over time gradually overwhelm somatic cellular repair mechanisms, leading to tissue degradation.

Lipofuscin

An insoluble, yellow-brown granular wear-and-tear pigment made of oxidized lipids and proteins that progressively accumulates inside postmitotic cells (such as cardiomyocytes and neurons), interfering with intracellular transport and metabolic signaling.

Free Radical Theory of Aging

A biological damage theory positing that oxidative cellular damage caused by reactive oxygen species (ROS) containing unpaired, highly reactive electrons damages cellular lipids, proteins, and DNA, contributing to aging and disease.

Hayflick Limit (Time-Clock Theory)

The biologically fixed ceiling on the maximum number of cell divisions normal human somatic cells can undergo in culture before entering permanent replicative senescence.

Telomere Theory

A programmed genetic theory positing that progressive shortening of repetitive DNA end-caps (telomeres) with each cycle of mitotic replication eventually triggers cellular senescence when critical threshold lengths are reached.

Cellular Senescence

A state of permanent growth arrest where cells remain metabolically active but cease dividing, secreting pro-inflammatory cytokines and signaling factors known as the senescent secretome.

Apoptosis

Genetically programmed cellular self-destruction that eliminates mutated, dysfunctional, or potentially hazardous senescent cells to protect organismal viability.

Apolipoprotein E (APOE) Gene

A lipid-binding protein gene located on chromosome $19$ whose $\varepsilon4$ allele significantly elevates the risk of late-onset Alzheimer's disease, while the $\varepsilon2$ allele provides neuroprotective resistance.

Brain-Derived Neurotrophic Factor (BDNF)

A neurotrophin active in the brain and spinal cord that fosters neuronal survival, axonal growth, and synaptic plasticity in the hippocampus, facilitating learning and memory retention.

Epigenome

A collection of chemical modifications to DNA and histone proteins, such as DNA methylation, that regulate chromatin architecture and gene expression without altering the genetic code.

Caloric Restriction

A dietary intervention reducing total caloric consumption without malnutrition, consistently demonstrated to decrease basal metabolic rate, attenuate oxidative damage, and extend median and maximal lifespan in non-human animal models.