Methods, Ethics, and Nervous System Organization Flashcards

Comprehensive vocabulary flashcards covering research methods, ethics, genetic research techniques, and nervous system anatomy and development.

Theory

A framework that integrates diverse observations into a complex structure and generates testable hypotheses.

Empiricism

The scientific method of relying on observation and experimentation, making scientific knowledge self-correcting and tentative.

Correlational Study

A study in which the researcher determines whether two variables change together without manipulating either variable, measured on a scale between $-1.0$ and $1.0$.

Experimental Study

A research design where the experimenter manipulates an independent variable to measure its causal effect on a dependent variable while controlling extraneous variables.

Independent Variable

The variable in an experiment that is directly manipulated or controlled by the experimenter.

Dependent Variable

The outcome variable measured by the researcher that results from changes in the independent variable.

Extraneous Variables

Uncontrolled influences in an experimental study that can potentially confound the results.

Golgi Stain

A neural staining technique that randomly stains approximately $5\%$ of neurons, rendering them visible against the background.

Myelin Stain

A staining technique specifically used to identify neural pathways by staining myelin sheaths.

Nissl Stain

A neural staining technique used specifically to identify the cell bodies of neurons.

Autoradiography

A technique in which uptake of a radioactive substance (such as 2-DG or radioactive naloxone) reveals which neurons are active during a specific behavior or locates specific receptors.

Immunocytochemistry

A technique using dye-attached antibodies to locate and identify specific cellular components within tissue.

Scanning Electron Microscope

A microscope that passes beams of electrons over tissue to reveal objects in 3-D with high resolution, magnifying objects up to $250,000\times$.

Electroencephalogram (EEG)

A device that records combined electrical activity from many neurons using multiple scalp electrodes, offering good temporal resolution but poor spatial resolution.

Evoked Potential Measurement

A procedure that averages EEG signals across multiple stimulus presentations using a computer to cancel background brain activity and isolate response to a stimulus.

Stereotaxic Atlas

A reference guide displaying images of series of brain sections to indicate the precise coordinates of key brain structures relative to landmarks.

Stereotaxic Instrument

A surgical device used to position an electrode or cannula at a precise location within the brain based on atlas coordinates.

Microdialysis

A technique using a stereotaxically placed cannula to extract fluid from the extracellular space of the brain to analyze chemical substances.

Ablation

The surgical removal of brain tissue to study its behavioral function.

Lesioning

The experimental technique of damaging neural tissue using heat, electrical current, neurotoxins, or severing connections to observe functional loss.

Transcranial Magnetic Stimulation (TMS)

A noninvasive procedure applying magnetic fields to excite or inhibit specific brain areas, used in research and therapeutics.

Family Study

A research design that assesses how strongly a characteristic is shared among relatives, though confounded by shared environments.

Adoption Study

A natural experiment comparing adopted children with their biological and adoptive parents to disentangle genetic influences from environmental factors.

Concordance Rate

The frequency or percentage with which relatives share a specific trait or clinical disorder (e.g., $17\%$ in fraternal twins vs. $48\%$ in identical twins for schizophrenia).

Knockout Technique

A genetic engineering method in which a nonfunctioning gene is introduced into embryos, resulting in organisms that lack the functional gene.

Antisense RNA

A procedure injecting complementary RNA that docks with a gene's mRNA, causing the cell to recognize it as abnormal and destroy it to block gene expression.

Transgenic Animal

An animal created by inserting a foreign or modified gene into a developing embryo so that it expresses an extra functional gene.

Gene Therapy

The application of genetic engineering to humans to alter or replace defective genes in order to treat medical disorders.

Plagiarism

The ethical violation of using another person's work or ideas without proper attribution, either intentionally or through carelessness.

Fabrication

The unethical practice of faking research data or results, which introduces false information into the scientific record.

Informed Consent

The ethical requirement that human research subjects voluntarily agree to participate after being fully educated on all potential risks and procedures.

Deception

Withholding the full purpose of a study or actively misinforming participants, ethically acceptable only when justified by value, lack of alternatives, and followed by debriefing.

Institutional Review Board (IRB)

A committee charged with reviewing and approving human research proposals to protect participant welfare.

Institutional Animal Care and Use Committee (IACUC)

A committee responsible for overseeing, monitoring, and enforcing ethical standards for animal care and use in research.

Tract

A bundle of nerve fibers (axons) traveling together within the central nervous system.

Nucleus (Nervous System)

A cluster of neuron cell bodies situated within the central nervous system.

Nerve

A bundle of nerve fibers (axons) traveling together in the peripheral nervous system.

Ganglion

A cluster of neuron cell bodies located in the peripheral nervous system.

Gyrus

A ridge or raised fold on the wrinkled surface of the cerebral cortex.

Sulcus

A groove or furrow separating adjacent gyri on the cerebral cortex.

Longitudinal Fissure

The prominent deep midline groove separating the left and right cerebral hemispheres.

Precentral Gyrus

The gyrus situated anterior to the central sulcus that contains the primary motor cortex.

Motor Homunculus

A map along the precentral gyrus illustrating the disproportionate amount of motor cortex assigned to controlling specific body structures.

Broca's Area

A region in the frontal lobe, usually in the left hemisphere, dedicated to speech production.

Prefrontal Cortex

The most anterior region of the frontal lobe, involved in executive functions including impulse control, planning, and decision making.

Frontal Lobotomy

A historical surgical intervention that severed connections between the prefrontal cortex and the rest of the brain to reduce agitation.

Primary Somatosensory Cortex

Located on the postcentral gyrus of the parietal lobe, it processes touch, skin senses, body position, and movement.

Spatial Neglect

A neurological condition caused by parietal lobe damage leading to lack of awareness for objects, people, and events on the opposite side of space.

Wernicke's Area

A region in the temporal lobe critical for understanding spoken and written language; damage results in fluent but nonsensical speech.

Thalamus

A forebrain structure that receives sensory signals (except olfaction) and relays them to appropriate cortical areas while helping regulate arousal.

Hypothalamus

A forebrain structure located beneath the thalamus that regulates autonomic functions, emotions, and drive behaviors like hunger, thirst, and sex.

Pineal Gland

A structure posterior to the thalamus that secretes melatonin to regulate circadian rhythms.

Corpus Callosum

A broad band of nerve fibers spanning the longitudinal fissure that connects and carries information between the two cerebral hemispheres.

Cerebrospinal Fluid (CSF)

The liquid filling the brain ventricles and spinal canal that carries nutrients to CNS tissue and removes metabolic waste.

Hydrocephalus

A condition caused by an abnormal accumulation of excess cerebrospinal fluid inside the cerebral ventricles.

Superior Colliculi

Midbrain structures that control visual reflexes and coordinate eye movements and gaze fixation.

Inferior Colliculi

Midbrain structures involved in auditory reflexes and localizing sound source direction.

Reticular Formation

A diffuse network of neurons spanning the hindbrain and midbrain involved in sleep, arousal, attention, reflexes, and muscle tone.

Substantia Nigra

A dopamine-producing nucleus in the midbrain that sends projections to the basal ganglia to integrate smooth motor control.

Ventral Tegmental Area (VTA)

A midbrain structure involved in mediating reward processing and reinforcement for pleasurable behaviors.

Medulla

The lower hindbrain structure controlling vital vegetative functions including cardiovascular activity and respiration.

Pons

A hindbrain structure containing reticular formation pathways that plays important roles in sleep and arousal.

Cerebellum

A large hindbrain structure that controls fine motor movements by adjusting movement speed, direction, and precision.

Meninges

The three protective membranes surrounding the central nervous system, consisting of the dura mater, arachnoid layer, and pia mater.

Blood-Brain Barrier (BBB)

A protective barrier of endothelial capillary cells joined by tight junctions that restricts entry of toxins and large molecules into brain tissue.

Area Postrema

A region in the medulla lacking a blood-brain barrier, enabling circulating toxins in the blood to trigger vomiting.

Somatic Nervous System

The division of the peripheral nervous system consisting of motor and sensory neurons that relay external sensory information and drive voluntary muscle actions.

Autonomic Nervous System (ANS)

The peripheral division that regulates involuntary activity of internal organs, glands, cardiac muscle, and smooth muscle.

Proliferation

The stage of nervous system development where neural stem cells in the ventricular zone divide and multiply, producing approximately $250,000$ new cells per minute.

Migration

The developmental stage in which newly formed neurons climb along radial glial cell scaffolds to reach their final anatomical positions.

Radial Glial Cells

Specialized glial fibers that provide structural guides for migrating neurons during brain development.

Circuit Formation

The stage of development where axon growth cones use chemical signals to navigate toward target cells and form functional synaptic connections.

Synaptic Pruning

The refined developmental process where unused, inactive synapses are eliminated while active neural connections are strengthened.

Fetal Alcohol Syndrome

A disorder caused by prenatal alcohol exposure resulting in microcephaly, malformed brain structure, and abnormal neuron migration away from columnar organization.

Ischemic Stroke

A stroke resulting from an arterial blockage, leading to oxygen and glucose deprivation in affected brain regions.

Hemorrhagic Stroke

A stroke caused by the rupture of a brain blood vessel.

Traumatic Brain Injury (TBI)

Brain damage caused by external physical forces such as direct impact, head penetration, or severe acceleration/deceleration.

Regeneration

The regrowth of severed axons following nerve damage, which occurs in the peripheral nervous system but is prevented in the central nervous system.

Compensation

A recovery mechanism following brain injury where intact neural tissue or adjacent areas adapt to take over functions lost by damaged regions.