INTERACTION OF HEREDITY AND ENVIRONMENT - AP PSYCH

Nature vs. Nurture

The debate over the relative contributions of genetics (nature) and environment (nurture) to human development.

Heredity (nature)

Genetic or predisposed characteristics that influenced physical, behavioral, and mental traits and processes.

Environment (nurture)

External factors that one experiences, characteristics; used in ways to discriminate against groups.

Twin studies

Research comparing similarities and differences in identical and fraternal twins.

Identical - monozygotic

Twins that share a placenta.

Fraternal - dizygotic

Twins that have separate placentas.

Family studies

Search for traits and diseases that tend to be shared by family members.

Adoption studies

Studies of adopted children to determine which traits are inherited vs. learned from the environment.

The Nervous System

The body's speedy, electrochemical communication network, consisting of all the nerve cells of the peripheral and central nervous systems.

Parasympathetic Nervous System

Responsible for maintaining bodily functions; releases acetylcholine.

Sympathetic Nervous System

Responsible for the fight or flight response.

Parts of a Neuron

Includes soma (cell body), dendrites (receives messages), axon (passes messages), myelin sheath (protects axon), axon terminal branches (transmits signals).

Reflex Arc

Neural pathway in the nervous system that allows organisms to respond to stimuli almost immediately and involuntarily.

SAME (Sensory/Afferent, Motor/Efferent)

Sensory (afferent) carries information to the brain; motor (efferent) carries information from the brain to muscles and glands.

Glial Cells

Cells in the nervous system that support, nourish, and protect neurons; plays a role in learning, thinking, and memory.

Neural Transmission

The process by which neurons communicate with each other, sending information through the nervous system.

Resting potential

In the fluid outside of an axon membrane sits positively charged (sodium) ions; inside the axon sit negatively charged (potassium) ions.

Threshold

Minimum level of pressure/stimulation required to trigger a neural impulse.

All or None Principle

States that a neuron will either fire with full strength or not fire at all.

Depolarization

When a neuron fires, positively charged atoms enter the axon.

Action Potential

A brief electrical charge that travels down the axon.

Refractory Period

A brief resting pause that occurs after a neuron has fired; action potential cannot occur again until the axon has returned to its resting state.

Reuptake

A neurotransmitter's reabsorption by the sending neuron.

Multiple Sclerosis (MS)

Deterioration of the myelin sheath, affecting vision, cognition, and movement.

Myasthenia gravis

Deterioration of acetylcholine, affecting muscles and speech.

Neurotransmitters

Chemical messages that cross the synaptic gap between neurons.

Excitatory neurotransmitters

Cause neurons to fire off messages.

Inhibitory neurotransmitters

Prevent messages from being passed along.

Adrenaline

Hormone associated with the fight or flight response.

Melatonin

Hormone that regulates sleep.

Ghrelin

Hormone that stimulates hunger.

Leptin

Hormone that suppresses hunger/weight.

Oxytocin

Hormone associated with love, labor, and lactation.

EEG (Electroencephalography)

Measures electrical activity in neurons using electrodes placed on the scalp.

MEG

Records magnetic fields from the brain's electrical currents.

CT (CAT scans)

Generates images of the head using x-rays to locate brain damage.

PET

Tracks where a radioactive form of glucose goes in the brain during a task.

MRI

Uses magnetic fields or radio waves to provide a map of brain structure.

fMRI

Measures blood flow to brain regions by comparing continuous MRI scans.

Brain stem

The oldest and central core of the brain, responsible for automatic survival functions.

Medulla

Controls heartbeat and breathing.

Pons

Helps coordinate movements, regulate sleep, and control facial expressions.

Cerebellum

Responsible for coordinating voluntary movement, balance, and procedural memory.

Cerebral cortex

Thin surface layer of interconnected neural cells; offers capacity for learning and thinking.

Thalamus

The brain's sensory switchboard that relays information about sight, hearing, taste, and touch.

Limbic system

Neural system associated with emotions and drives, includes hypothalamus, hippocampus, and amygdala.

Corpus Callosum

Band of neural fibers that connects the two hemispheres of the brain.

Frontal lobe

Responsible for linguistic processing, executive functioning, and higher order thinking.

Motor cortex

Controls most types of skeletal movements.

Somatosensory cortex

Processes touch sensory input.

Parietal lobe

Processes and organizes sensory input for touch and body position.

Occipital lobe

Receives visual information from the opposite visual field.

Temporal lobe

Includes auditory areas and allows recognition of faces.

Broca's Area

Controls speech muscles via the motor cortex; responsible for language production.

Broca's aphasia

Able to understand speech but unable to speak.

Wernicke's Area

Interprets auditory code; responsible for language comprehension.

Wernicke's aphasia

Able to speak but unable to understand spoken and written language.

Split-brain research

Cutting into the corpus callosum to study the two hemispheres.

Right hemisphere

Involved in perceptual tasks, self-awareness, and inference-making.

Left hemisphere

Responsible for language and math.

Cortex Specialisation

Different regions of the cerebral cortex have different functions.

Contralateral hemispheric organisation

Each hemisphere primarily controls the opposite side of the body.

Brain plasticity

The ability of the brain to rewire or modify itself and create new connections.