CDIS 421 Midterm Flashcards

A comprehensive set of vocabulary flashcards for the CDIS 421 Midterm, covering neuroanatomy, cellular biology of the nervous system, and vascular supply systems of the brain and brain and spinal cord.

Neuron and glial cells

The two types of cells that make up the nervous system.

Glial cells

Cells in the nervous system that support, nourish, and protect neurons; they are more numerous than neurons.

Dendrite or soma

The portions of the neuron that receive input.

Axon hillock

The portion of the neuron where all input is mixed together and action potentials are initiated.

Presynaptic terminal

The part of a neuron that passes the signal onto the next neuron.

Multipolar

The most common neuron shape, consisting of a dendrite out of the soma and an axon going the other way.

Afferent

A sensory neuron that carries information TO the CNS.

Efferent

A neuron that carries signals FROM the CNS to the muscles.

Red blood cells

Cells from which DNA cannot be obtained because they lose their nucleus.

Schwann Cells

Glial cells that form myelin in the Peripheral Nervous System (PNS).

Oligodendroglia

Glial cells that form the myelin sheath in the Central Nervous System (CNS).

Microglia

Glial cells that consume harmful substances.

Astrocytes

Glial cells that help form the blood brain barrier.

Resting membrane potential

The voltage of a neuron at rest, which is $-70\,mV$.

Concentration gradient

the driving force that causes an ion to move in order to achieve uniform distribution.

Electrical gradient

The driving force that causes an ion to move because of its positive or negative charge.

Functional zones of a neuron

The four zones: input zone, integration zone, conduction zone, and output zone.

Calcium

The ion whose channels are opened by depolarization in the axon terminals.

Synaptic transmission termination

The three ways a transmission ends: Diffusion (float away), degradation (broken down by enzymes), and re-uptake (taken back in by the presynaptic neuron).

Spatial summation

A mechanism to reach firing threshold where multiple presynaptic neurons release neurotransmitters together.

Temporal summation

A mechanism to reach firing threshold where one presynaptic neuron releases neurotransmitters over a period of time.

Cortex

Sheets of cell bodies combined together.

Nuclei

Groups of cell bodies located in the CNS.

Ganglia

Groups of cell bodies located in the PNS.

Gray matter

Matter mainly consisting of dendrites or unmyelinated axons; includes nuclei and ganglia.

Nerves

Bundles of axons located in the PNS.

Pathways, fibers, or tracts

Bundles of axons located in the CNS.

Spinal cord

The chief input and output site for sensory and motor signals between the body and the nervous system; its most basic function is the reflex.

Fasciculus gracilis

A structure seen throughout the entire spinal cord.

Fasciculus cuneatus

A structure present in the uppermost region of the spinal cord.

4th ventricle

The portion of the brain system that drains CSF.

Pons

The portion of the brainstem characterized by horizontal stripes.

Sagittal

A brain section or view that divides a structure into left and right.

Coronal

A brain section that divides the structure into front and back parts.

Horizontal

A brain section that divides a structure into upper and lower portions.

Distal

Away from center.

Dorsal

The back of the body; also refers to the superior cerebrum or posterior spinal cord.

Rostral

Toward the nasal region; also refers to the anterior cerebrum or superior spinal cord.

Ventral

The front of the body; also refers to the inferior cerebrum or anterior spinal cord.

Lateral

Away from midline.

Proximal

Closer to the trunk.

Caudal

Away from the head; also refers to the posterior cerebrum or inferior spinal cord.

Contralateral

Opposite side.

Diencephalon

A part of the brain containing the thalamus and hypothalamus.

Thalamus

A structure that regulates sleep, alertness, and wakefulness.

Hypothalamus

The body's homeostatic regulatory system.

Longitudinal fissure

The structure that separates the two cerebral hemispheres.

Corpus callosum

The largest commissural fiber that connects the two cerebral hemispheres.

Cerebral cortex

The thin layer of gray matter on the surface of the cerebral hemisphere responsible for higher level processes.

Primary motor cortex

Located on the precentral gyrus of the frontal lobe.

Primary somatosensory cortex

Located on the post central gyrus of the parietal lobe.

Primary auditory cortex

Located on the transverse temporal gyri (Heschl's gyri) of the temporal lobe.

Primary visual cortex

Located on the walls or edges of the calcarine fissure in the occipital lobe.

Prefrontal cortex

The primary location for executive functions.

Intraparietal sulcus

The sulcus that divides the superior and inferior parietal lobes (or lobules).

Broca's area

Brain region responsible for speech production.

Wernicke's area

Brain region responsible for language comprehension.

Limbic system

A system deep in the brain involving emotion and memory; includes the hippocampus, amygdala, hypothalamus, and thalamus.

Association fibers

Fibers that connect two parts of the same hemisphere.

Projection fibers

Fibers that carry information between the cortex and the body (spinal cord).

Commissural fibers

Fibers that connect one hemisphere to the other.

Internal capsule

A type of projection fiber from which the corona radiata extends.

Arcuate fasciculus

An association fiber that connects Broca's area and Wernicke's area.

Vermis

The midline structure of the cerebellum.

Premotor cortex

The location where motor planning occurs.

Meninges

The three protective layers of the brain: dura mater, arachnoid mater, and pia mater.

Middle cerebral artery

The most important artery for SLPs; damage can cause expressive and receptive language disorders due to blood loss.

Carotid and vertebrobasilar

The major arterial systems that supply blood to the brain.

Ventral roots

Roots of the spinal nerves that are motor in function.

Dorsal roots

Roots of the spinal nerves that are sensory in function.

Ascending fibers

Fibers of the spinal cord that carry sensory information.

Descending fibers

Fibers of the spinal cord that carry motor information.

Lower motor neurons

Classification for cranial and spinal nerves.

Vagus nerve

The nerve that moves the velum.

Sodium ($Na$)

The ion that rushes into the axon resulting in an action potential and depolarization.

Voltage of an action potential

$$+50\,mV$$

Repolarization

A process occurring because of the outward flow of potassium ($K$).

Synapse

The point of communication between two neurons.

Dopamine

A modulatory neurotransmitter produced in the substantia nigra.

Acetylcholine

The primary neurotransmitter of the PNS, occurring in synapses with muscle tissue.

Central sulcus

Separates the frontal and parietal lobes.

Lateral sulcus

Separates the temporal lobe from the parietal and frontal lobes.

Basal ganglia

A group of 5 structures: Caudate nucleus, Putamen, Globus pallidus (cerebral hemispheres), Subthalamic nucleus (diencephalon), and Substantia nigra (midbrain).

Circle of Willis

A circle of arteries at the base of the brain that supplies circulation and can reroute blood flow if a major artery is blocked.