Biology, Brain, and Behavior (Hyde) - Lecture Flashcards

A comprehensive set of Q&A flashcards covering prenatal development stages, brain structure, basic neurodevelopmental processes, environmental influences, and critical/sensitive period concepts from the lecture notes.

What prenatal stage occurs from conception to the 2nd week and involves rapid cell division, with the zygote forming the neural plate that folds into the neural tube?

Germinal stage.

Which prenatal stage spans roughly 3rd to 8th week and includes cell differentiation, cell migration, major organ development, and the emergence of hemispheres?

Embryonic stage.

Which prenatal stage lasts roughly from the 9th week to birth and involves major brain growth, neuro- and synaptogenesis, and gyrification?

Fetal stage.

What period is defined as birth to about 1 month after birth?

Neonatal period.

What period is defined as anytime after birth?

Postnatal period.

What time frame is described as infancy in this lecture notes?

Birth to about 2 years (24 months).

What is gray matter primarily composed of?

Neuronal cell bodies and the cerebral cortex (surface/top layers).

What is white matter primarily composed of, according to the notes?

Glial cells and connective/supportive tissue forming white matter fibers; myelinated tracts.

Name the basic parts of a neuron.

Axon, dendrite, and synapse.

What is neurogenesis?

Growth of new neurons; ~250,000 per minute prenatally until about 100 billion neurons are reached; mostly stops around birth.

What is synaptogenesis?

Exuberant growth of connections between neurons during prenatal development; peaks around 1 year; more connections in the infant brain than adult brain; region timing varies.

What is gyrification?

Formation of sulci (depressions) and gyri (ridges); brain folds to fit the skull;Starts prenatally and is fully present around 1 year after birth.

What are the four lobes of the cerebral cortex?

Frontal, Temporal, Parietal, and Occipital lobes.

What is the primary function of the frontal lobe?

Higher order cognition: planning, information integration, inhibition, decision making, movement.

What is the primary function of the temporal lobe?

Auditory processing, memory, and sensory integration.

What is the primary function of the occipital lobe?

Visual signal processing and representation.

What is the primary function of the parietal lobe?

Somatosensory processing (touch), attention, short-term memory, sensory integration, and spatial representation.

What does hemispheric organization refer to?

Two halves (left and right) of the brain with generally symmetrical structures but some functional asymmetries.

What does contralateral organization mean in brain function?

Sensory information and motor/somatosensory control cross to the opposite hemisphere (e.g., left visual field to right hemisphere).

What does retinotopic organization describe?

Visual system is organized spatially according to how light from the retina maps to the brain.

What does somatotopic organization describe?

Motor and somatosensory areas are organized like a map of the body.

What is myelination?

Growth of fatty myelin around axons; speeds up signal transmission; begins prenatally and is mostly postnatal; earlier in brainstem than in frontal regions.

What are teratogens?

Environmental agents that can harm a developing organism during pregnancy (e.g., drugs, pollutants, BPA, DEHP, occupational hazards).

What is the dose-response relationship in prenatal development?

The amount of exposure to an environmental factor influences the outcome.

What is a sensitive period?

An optimal or opportunity-rich time window during development when experiences have particularly strong effects; begins and ends gradually.

What is a critical period?

A window during development when certain experiences must occur; ends abruptly; consequences are often irreversible if missing.

Give an example of a classic critical period in animals.

Imprinting in geese (Konrad Lorenz): must occur within about 0-36 hours after hatching.

What did Hubel & Wiesel demonstrate about vision development?

A critical period in kittens: deprivation of input during the first 3 months leads to lasting vision deficits; deprivation timing matters.

What does the kitten carousel study illustrate about depth perception?

Kittens must experience self-movement and depth cues within ~3 months to develop normal depth perception; being moved by a carousel without self-motion impedes it.

What are Experience-Expectant (E-E) and Experience-Dependent (E-D) processes?

E-E: development from general experiences all members of a species are likely to have (e.g., patterned visual input); deprivation can cause severe deficits. E-D: development from idiosyncratic, individual experiences (e.g., language phoneme exposure, music perception).

What is synaptic pruning and why does it occur?

Systematic loss of synapses (about 40%) after excess synaptogenesis; driven by experience; starts prenatally and continues into early adulthood; different regions prune at different times.

What is Hebb's rule in the context of brain development?

Cells that fire together wire together; coordinated activity strengthens synapses.

What is perceptual narrowing?

Loss of ability to discriminate perceptual distinctions not commonly experienced, as the brain tunes to familiar environmental features; linked to pruning.

What happens in perceptual narrowing for language (Kuhl et al.)?

Infants can distinguish all phonemes up to about 8 months; by 8–12 months, they specialize in their native language phonemes and lose non-native distinctions.

What happens in perceptual narrowing for music (Hannon et al.)?

By around 12 months, infants show narrowing to the musical structure of their culture (e.g., Western meter) and lose sensitivity to non-native musical structures.

What are Experience-Expectant vs. Experience-Dependent processes in a sentence?

E-E: development from common species-wide experiences; E-D: development from individual experiences; both shape brain wiring.

What is the role of poverty/SES in prenatal brain development?

Low SES is associated with multiple risks and less optimal infant outcomes; dose-response and timing of exposure matter.

What is the role of education in critical/sensitive periods?

Early educational experiences (Head Start, Montessori, early intervention) leverage windows of opportunity to support development.

What is the key takeaway about early brain development from these notes?

Development unfolds systematically through proliferation, consolidation, and experience; the environment—amount and timing of experience—significantly shapes outcomes.

What is the significance of the visual cortex vs. prefrontal cortex pruning pattern?

Visual cortex pruning occurs earlier; prefrontal cortex pruning extends into adolescence, reflecting later maturation of higher-order functions.

What is an example of cross-modal plasticity in sensory-deprived individuals (Neville et al., 1998)?

Congenitally deaf individuals can recruit auditory cortex for visual processing when learning sign language (ASL).

What is the timing takeaway for critical vs. sensitive periods in education and development?

Many skills are better viewed as sensitive periods rather than strict critical periods; timing matters, but not all developments have a single hard cutoff.