A&P 1 Test 4- Dr. Baker

Absence seizure

A mild seizure similar to daydreaming; occurs mostly in children; caused by depressed hypothalamus/thalamus brain waves; disappears by age 10; shorter duration.

Alpha waves

Small and regular; indicate calm, relaxed, awake state.

ALS

Amyotrophic lateral sclerosis; Lou Gehrig's Dz; progressive destruction of the anterior horn motor neurons.

Alzheimer's

A progressive degenerative dz of the brain that ultimately results in dementia; memory loss, shortened attention span, disorientation, language loss, hallucinations; autopsy revels beta-amyloid plaques (protein, dead cells, fibers).

Anterograde amnesia

Caused by damage to the hippocampus and amygdala; no new memories can be formed; "short term memory loss"; (inability to form new memories)

Ataxia

Disruption of synergy; impaired coordination.

Ex: unsteady gait

Aura

A sensory hallucination that occurs before some grand mail seizures; bright lights, distortions, nausea, blind spots, smells, numbness, etc.

Beta waves

Small, slightly irregular; occur when mentally alert or during concentration.

Cerebellum

11% of total brain mass; needed for smooth, coordinated skeletal muscle movements ("synergy")

Cerebral cortex

(edges); our "consciousness": where our initiation of voluntary movement occurs; 3 functional areas: motor, sensory, association;

1. Motor: areas that control skeletal muscle contraction

2. Sensory: receives sensory [afferent] impulses from sensory organs [eyes/ears/nose/tongue/skin] and filters those impulses through stores memories to create a conscious thought or awareness of the sensation; are unipolar.

3. Association: integrates diverse information from both the sensory and motor areas; prefrontal cortex (only area not fully developed at birth) — involved in personality, judgement, reasoning, concern for others, conscience; develops slowly in children; completely developed in 20's; severed in prefrontal lobotomy.

Cerebral edema

Swelling [fluid buildup] of cerebrum.

Choroid plexus

Red arch that secretes CSF from blood vessels into ventricles.

Coma

Extended period of unresponsiveness to stimuli; period of prolonged unconsciousness.

Concussion

Slight brain injury, sx short-lived; no permanent neurological damage; increased amounts of concussions = increased CNS damage.

Conus medullaris

Termination of spinal cord at L1.

Cordotomy

Tract removal in the spinal cord due to unremitting pain; permanently killing sensory neurons in dorsal horn for pain relief.

Corpus callosum

Commissure: fibers that connect the gray areas of the two hemispheres [are symmetrical anatomically but not physiologically] of cerebral cortex.

CSF

Leaks from capillaries into choroid plexi into the ventricles then circulates through the subarachnoid matter and is reabsorbed back into the circulatory system there; forms as a filtrate containing glucose, oxygen, vitamins, and ions; used for protection and refreshing brain.

Delta waves

Large, irregular; occur during deep sleep or amnesia.

Dorsal horns

Posterior horns; sensory (to CNS).

Dorsal roots

Axonal extensions of afferent sensory. Nerves entering the spinal cord (to CNS).

EEG

Electroencephalogram; an electrical measurement of brain waves/activity; looking at mass depolarization.

Encephalitis

Inflammation of brain tissue.

Epilepsy

Uncontrollable seizures caused by abnormal electrician discharges from the brain; 1 in 25 people; PMHx: genetics, tumors, injury, stroke, infection, etc.

Epithalamus

A part of the diencephalon [central core of brain; control smooth muscle/cardiac muscle]; pineal gland extends from here and secretes melatonin; contains choroid plexus which secretes CSF from blood vessels into ventricles.

Filum terminale

Fibrous extension of the pia matter; a part of the spinal cord.

Fissures

Deeper grooves that separate large regions of the cerebral cortex (separates lobes).

Flaccid paralysis

Severe damage to the ventral root or anterior horn cells; skeletal muscles cannot move voluntarily or involuntarily; atrophy; from damage to spinal cord.

Clonic/tonic seizure

Grand mal seizure; very rapid brain waves cause convulsions and unconsciousness; broken bones, loss of bowel/bladder control, biting tongue; longer duration.

Gyri

Elevated ridges of tissue.

Hippocampus

An area of the brain important for memory processing and storage (memory formation).

Huntingon's

Example of disrupted synergy; inherited disorder, genetic mutation; progressive degeneration of the basal nuclei in the cerebrum; chorea (uncontrolled writhing), mental deterioration, behavioral disturbances, hallucinations, psychosis, dementia (umbrella term); quick progression.

Hydrocephalus

Buildup of CSF causing bones of skull to separate/expand causing an enlarged cranium.

Hypothalamus

A part of the diencephalon [central core of brain; control smooth muscle/cardiac muscle]; below the thalamus; controls pituitary gland-most important endocrine gland (produces hormone); main area of brain controlling organ function; main visceral control center for the body (autonomic NS); critical for body homeostasis.

Insomnia

The chronic inability to obtain the amount or quality of sleep needed.

Lobotomy (prefrontal)

Surgical procedure where the prefrontal cortex is detached from the rest of the cerebral cortex; previously used to "cure" mental illness.

Lumbar puncture/spinal tap

Removal of CSF from the subarachnoid space inferior to L3; spinal cord terminates at L1; rural and arachnoid membranes extend to S2.

Medulla oblongata

A part of the brain stem [responsible for involuntary processes necessary for our survival— reflexes]; maintains body's homeostasis; the hypothalamus exerts its control over most autonomic functions by relaying its instructions through medulla, which carries them out; where nuclei/neurons actually synapse with smooth and cardiac muscle.

Meninges

Provide protection; 3 layers surrounding the brain & spinal cord:

1. Dura matter (most superficial) - durable, most collagen ours/fibrous, up against bone.

2. Arachnoid matter- thinner, heavy on collagen.

3. Pia matter- thinnest/most delicate, heavy on collagen.

Meningitis

Inflammation of meningies usually caused by a bacterial/fungal/viral infection.

Midbrain

A part of the brain stem [responsible for the involuntary processes necessary for our survival— reflexes]; several nuclei; largest is the corpora quadrigemina (2 superior, 2 inferior colliculi); visual/auditory reflexes.

Myelitis

Inflammation of spinal cord; progressive.

Myoclonus

A fleeting skeletal muscle contraction, often while falling asleep; sometimes causes falling sensation; involuntary.

Narcolepsy

Involuntary lapses into sleep.

NREM sleep

Non rapid eye movement; stage 1: eyes closed, body relaxes, viral signs and EEG normal; stage 2: EEG becomes irregular; Stage 3: theta and delta waves appear, vital signs slow; stage 4: delta waves predominate, vital signs very slow.

Paraplegia

Paralysis of legs due to damage between T1-L1

Paresthesia

Abnormal sensation resulting from a sensory nerve disorder; burning, numbness, tingling.

Parkinson's

Example of disrupted synergy; degeneration of dopamine producing neurons in the brain stem; tremors, lack of factual expression, difficulty walking (ataxia); slow progression.

Phantom pain

Pain in an amputated limb; due to damaged sensory neuron firing.

Pineal gland

Extends from epithalamus and secretes melatonin; a part of the diencephalon.

Poliomyelitis

Destruction of gray matter, specifically the anterior horn motor neurons; caused by polos virus; sx include fever, ha, muscle pain, weakness, paralysis, atrophy, death from paralysis of respiration muscles; feces-contaminated water- children in the Summer; largely eradicated by vaccine.

Pons

A part of the brain stem [responsible for involuntary processes necessary for our survival — reflexes]; site of pneumonia is and a pneumatic centers; controls rate of breathing (nuclei that control respiration rate).

Prefrontal cortex

Only area not fully developed at birth — involved in personality, judgement, reasoning, concern for others, conscience; develops slowly in children; completely developed in 20's; severed in prefrontal lobotomy.

Psychosomatic illness

Increased emotional stress leds to visceral illness; lambic system responds to emotional stimuli, output- hypothalamus, extensive hypothalamus stress affects the autonomic system.

Ex: illness

Quadriplegia

Paralysis of legs and arms due to damage between C4-L1.

REM sleep

Rapid eye movements brain waves become more active, dreaming occurs.

Retrograde amnesia

Loss of past memories; what is lost depends on where the brain damage is.

Spastic paralysis

When only the upper motor neurons of the primary motor cortex are damaged; spinal motor neurons remain intact, muscles continue to be stimulated irregularly (not voluntarily) by spinal reflex activity therefore remain healthy longer but eventually shorten and fibrose.

Stroke

When blood circulation to a brain area is blocked and brain tissue dies.

Subdural hemorrhage

Bleeding from raptured vessels into the subdural space; may result in death; victims are lucid and then deteriorate neurologically very quickly as accumulating blood puts pressure on the brain, pushing the brain stem through the foramen magnum; sx include decreased/loss of BP/HR and respiration control.

Sulci

(Pleural) shallow groves between Gyri.

Suprachiasmatic nucleus

A biological clock in the hypothalamus that helps regulate sleep.

Synergy

Smooth, coordinated skeletal muscle movements.

Thalamus

A part of the diencephalon [central core of brain; control smooth muscle/cardiac muscle]; gateway to cerebral cortex; communicates with the cortex when it receives afferent (sensory) impulses from the body [senses filtered through thalamus before reaching cerebrum where sensory impulse occurs]; sorts out and edits information and sends edited information to the sensory areas of the cortex.

Theta waves

Medium, irregular; early sleep waves; common in children.

TIA

Transient ischemic attack; mini stroke; sx include numbness, paralysis, impaired speech; are red flags for strokes/CVA's.

Ventral horns

Anterior horns; motor; house cell bodies of somatic motor neurons [to PNS].

Ventral roots

Axonal extensions of somatic motor neurons on their way to muscles [to PNS].

Ventricles

Central cavities within the brain and spinal cord where CSF flows.

Neuroglia

Nerve pain; typically sharp/spasmodic.

Dura matter

most superficial, durable, most collagen/ fiberous, is up against the bone.

Arachnoid matter

thinner, heavey on collagen.

Pia matter

thinnest / most delicate, heavy on collagen.

Afferent

carrying sensory information toward a central organ or part, as a nerve that conducts impulses from the periphery of the body to the central nervous system.

Anterograde

the inability to form new memories.

Astrocytes

star shaped glia cells in the nervous system (CNS) that provide essential structral, metabolic, and functional support to neurons. Repsonsible for maintaining brain homestasis, recycling neurotransmitters, forming the blood-brain barrier, and modulating blood flow.

Chemically-gated channels

transmembrane protein structures that open and close to allow specific ions to pass through the cell membrane in response to the binding of a chemical messenger.

Efferent

refers to nerve fibers, neurons, or vessels that conduct impulses or fluids outward, away from a central structure like the brain, spinal cord, or an organ.

Ependymal cells

specialized, ciliated neuroepithelial glial cells that form the thin epithelial lining (ependyma) of the brain's ventricles and the central canal of the spinal cord.

Ganglia

is a cluster of neuron cell bodies located in the peripheral nervous system (PNS).

Glioma

a type of tumor that occurs in the brain and spinal cord, arising from glial cells that support and nourish neurons.

Gray matter

Is a major component of the central nervous system, primarily composed of neuronal cell bodies, dendrites, and glial cells. It acts as the brain's "processing center," responsible for handling information, controlling voluntary movement, memory, emotions, and sensory perception (sight, hearing)

Microglia

Are a class of brain cells that act as immune effector cells in the central nervous system, displaying functions such as phagocytosis, antigen presentation, and production of various immune-related molecules.

Multiple sclerosis

Is a chronic, often disabling autoimmune disease of the central nervous system (brain, spinal cord, and optic nerves). The immune system attacks the protective myelin coating on nerves, causing inflammation and damaging communication between the brain and body, which results in unpredictable symptoms like vision loss, pain, fatigue, and muscle weakness.

Nerves

Thin, cord-like bundles of fibers that act as the body’s wiring system, carrying electrical signals between the brain/spinal cord and all other parts of the body.

Neuroblastoma

A cancer that develops from immature nerve cells primarily in infants and young children, usually starting in the adrenal glands or nerve tissue in the abdomen, chest, or neck. It is the most common extracranial solid tumor in children, often diagnosed before age 5.

Neuron

specialized, electrically excitable cells that act as the fundamental structural and functional units of the nervous system, responsible for transmitting information throughout the body via electrical and chemical signals. They possess a unique anatomy designed for communication, consisting of a cell body (soma), dendrites, and an axon

Neurotoxin

A substance that damages, destroys, or alters the normal function of the nervous system (brain, spinal cord, and nerves).

Neurotransmitter

They are endogenous chemical messengers that allow neurons to communicate with each other, muscles, or glands by traversing the synapse.

Nuclei

The membrane-enclosed organelle within a cell that contains the chromosomes.

Oligodendrocytes

Specialized neuroglial cells in the central nervous system (CNS) that produce myelin, a fatty substance forming an insulating sheath around neuronal axons.

Retrograde

Movement, flow, or signaling that occurs backward, opposite to the normal, natural, or intended direction.

Saltatory conduction

The rapid, "jumping" propagation of action potentials along myelinated axons, from one node of Ranvier to the next.

Schwann cells

The primary glial cells of the peripheral nervous system (PNS) that wrap around axons to provide insulation (myelin sheath), metabolic support, and nerve regeneration assistance

Stimulus

Any detectable change in an organism's internal or external environment that triggers a behavioral or physiological response.

Synapse

The specialized junction where a neuron (nerve cell) communicates with another neuron, muscle, or gland cell, transmitting signals via chemical neurotransmitters or direct electrical currents. It acts as a signaling gap, converting electrical impulses into chemical signals to relay information throughout the nervous system.

Tracts

A bundle of nerve fibers (axons) within the central nervous system (CNS) that share a common origin, destination, and function, facilitating communication between brain/spinal cord regions.

Voltage-gated channels

Specialized transmembrane proteins that open or close in response to changes in the membrane potential of a cell.

White matter

A component of the central nervous system composed primarily of myelinated axons, acting as the wiring that connects different brain regions.