Nervous System Anatomy, Physiology, and Disorders

Comprehensive vocabulary flashcards covering the Central Nervous System, Peripheral Nervous System, neuronal transmission, reflex arcs, neurochemistry, and neurological disorders based on lecture notes.

Reflex Arc

A neural circuit composed of a sensory neuron, associative neuron, and motor neuron that triggers a motor response faster than a message reaches the brain.

Cerebral Palsy

A disorder caused by abnormal brain development resulting in multiple physical effects, for which there is no cure.

Epilepsy

A neurological condition with unidentified causes characterized by minor to major seizures, managed using medication.

Multiple Sclerosis

A degenerative neurological disease involving the destruction of myelin and the misfiring of neurons, having no cure.

Poliomyelitis

A condition caused by the Polio virus that leads to paralysis, preventable through vaccination.

Parkinson's Disease

A disease marked by the loss of dopamine-producing cells, resulting in sporadic movements and loss of control; treated with medication to slow progression, but has no cure.

Alzheimer's Disease

A progressive disease characterized by the death of brain cells and memory loss, for which there is no cure.

Meningitis

Inflammation of the meninges that can cause seizures and neurological damage; treated with antibiotics and preventable by vaccine.

Concussion

Physical damage to the brain that requires rest and recuperation for recovery.

Resting Membrane State

The state of an unstimulated neuron characterized by a high concentration of $Na^+$ outside the membrane and a high concentration of $K^+$ inside the membrane.

Action Potential

A nerve impulse traveling at speeds up to $120\,\text{m/s}$, initiated when stimulus changes plasma membrane permeability so $Na^+$ rushes inward and $K^+$ rushes outward, after which the sodium/potassium pump restores resting conditions.

Acetylcholine (Ach)

A neurotransmitter that diffuses across the synapse into the synaptic cleft to potentially trigger a nerve impulse.

Acetylcholinesterase (Ach. Esterase)

An enzyme released into the synapse to break down acetylcholine.

Classical Conditioning

A learning theory associated with Pavlov where an organism learns to associate a stimulus with a good or bad event.

Operant Conditioning

A learning theory associated with Skinner where an organism learns through trial and error to behave in a certain way to receive a reward or avoid punishment.

Initial Attraction

A process occurring in the first $1.5\text{--}4\,\text{min}$ determined $55\%$ by body language, $38\%$ by tone and speed of voice, and $7\%$ by what is spoken.

Phenylethylamine (PEA)

A neurochemical that floods the brain upon first attraction and heightens the effects of norepinephrine and dopamine.

Norepinephrine

A neurotransmitter involved in attraction that increases heart rate, sweating, breathing, and alertness.

Dopamine

A neurotransmitter that induces feelings of pleasure and satiation.

Serotonin

A neurotransmitter hyperactive for approximately 4 months during early romantic love that drives fixation on pleasure and impairs critical thinking.

Oxytocin

A neurochemical released during moments of intimacy that fosters codependence and a desire for physical proximity during the attachment phase.

Central Canal

A small opening running the entire length of the spinal cord that is filled with cerebrospinal fluid.

Ascending Tracts

Myelinated nerve pathways in the spinal cord that transmit sensory impulses upward to the brain.

Descending Tracts

Myelinated nerve pathways in the spinal cord that transmit motor impulses downward from the brain.

Neuroglial Cells

Non-neuronal cells of nervous tissue dedicated to supporting neurons.

Perikaryon

The cell body of a neuron consisting of neuroplasm surrounding a central nucleus.

Dendrites

Short, highly branched extensions of a neuron that conduct nerve impulses toward the perikaryon.

Axon

A single long extension of a neuron that conveys impulses away from the perikaryon and terminates in synaptic knobs.

Axis Cylinder

The central core structure of a nerve fiber.

Schwann Cells

Specialized cells that wrap around and insulate peripheral nerve fibers to produce the myelin sheath.

Nodes of Ranvier

Indentations or periodic gaps located along the nerve fiber between adjacent Schwann cells.

Somatic Division

The division of the peripheral nervous system composed of motor neurons.

Autonomic Division

The division of the peripheral nervous system responsible for maintaining dynamic equilibrium (such as temperature, smooth muscles, and heartbeat), divided into sympathetic and parasympathetic systems.

Sympathetic System

The activating branch of the autonomic nervous system that operates antagonistically to the parasympathetic system.

Parasympathetic System

The relaxation branch of the autonomic nervous system that operates antagonistically to the sympathetic system.

Cerebrum

The brain region responsible for conscious thought, speech, memory, logic, and emotion.

Cerebellum

The brain structure that coordinates movement and temperature.

Midbrain

The portion of the brain that processes visual and auditory signals.

Pons

A brain structure that oversees unconscious processes, specifically the sleep cycle and breathing.

Medulla Oblongata

The brainstem structure that coordinates autonomic functions.

Thalamus

The primary sensory relay center of the brain.

Hypothalamus

The brain structure responsible for maintaining homeostasis.

Pituitary Gland

An endocrine gland regulated by the brain that directs multiple other glands and organs.

Meninges

A three-layered protective covering of the brain and spinal cord comprised of the pia mater, arachnoid mater, and dura mater.

Blood-Brain Barrier

A protective barrier formed by tightly packed endothelial cells that shields the central nervous system.

Frontal Lobe

The cerebral cortex lobe managing language and executive function, whose upper section controls the lower parts of the body.

Temporal Lobe

The cerebral cortex region dedicated to auditory processing and memory.

Parietal Lobe

The cerebral cortex region dedicated to sensory perception.

Occipital Lobe

The cerebral cortex region dedicated to visual perception.

Broca's Area

A specialized area in the cerebral cortex that coordinates speech.

Gyri and Sulci

The elevated ridges (gyri) and shallow valleys (sulci) on the cerebral cortex that serve to increase surface area.

Fissures

Deep grooves that divide the cerebrum into right and left hemispheres, each controlling the opposite side of the body.

Spinal Cord

A nervous structure continuous with the brain emerging through the foramen magnum, measuring $42\text{--}45\,\text{cm}$ in length and terminating near the 1st and 2nd lumbar vertebrae.

Cauda Equina

A bundle of spinal nerves continuing downward past the lower end of the spinal cord.

Gray Matter (Spinal Cord)

The central H-shaped region of the spinal cord composed of unmyelinated neurons.

Anterior Horns

Projections of spinal gray matter that lead into motor nerve fibers.

Posterior Horns

Projections of spinal gray matter that receive impulses from sensory neurons.