142 terms

Anatomy of Neurology

Test 4
functional and communicating unit of the nervous system
glial cells
supportive cell of the nervous system
cell body of the neuron
long part of the neuron, transmits information away
branches of neuron, transmits information into the cell
axon hillock
where the axon meets the body of the neuron
myelin sheath
fatty layers of the neuron that wrap around the axon
makes up the myelin sheath, part of the central nervous system
Schwann cells
make up the myelin sheath, part of the peripheral nervous system
nodes of ranvier
constriction in the axon
end of the dendrites, root-looking things
saltatory conduction
jumps from the axon of one neuron to the dendrites of another
synaptic vesicles
contain neurotransmitters which jump from the synaptic boutons across the synaptic cleft during saltatory conduction
synaptic cleft
space between the boutons across which the synaptic vesicles jump
synaptic boutons (knobs)
where the neurotransmitters are stored, end of the synapse
store information that is relayed in synapse
neurotransmitter found in CNS and PNS in humans
peripheral nervous system
includes cranial and spinal nerves, sensory receptors autonomic nervous system
central nervous system
includes the brain and spinal chord
autonomic nervous system
controls the internal environment of the bod, is self regulating; includes the sypmathetic system (fight or flight) and the parasympathetic system
sympathetic system
(or thoracolumbar) the "fight of flight" instinct; increases heart rate vasoconstriction (blood vessels), dilates pupils, surges adrenaline
Parasympathetic system
(or craniosacral) relaxes the body, lowers heart rate and blood pressure
afferent neurons
"arriving" conduct toward the central nervous system (ascending, often to sensory nerons)
efferent neurons
"exiting" conducting away from the central nervous system (descending and often motor)
cranial nerves
On, on, on they traveled and found Voldemort guarding very ancient horcruxes
spinal nerves
31 pairs of spinal nerves, numbered C1-C8, T1-T12, L1-5, S1-S5 C1
conus medullaris
at L3 at birth, adults at L1, terminal end of the spinal chord
filum termina
delicate strand of fibrous tissue,downward from the apex of the conus medullaris, gives longitudinal support to the spinal cord, made up of cauda equina
cauda equina
"horse tail" end of the filum termina, bundle of nerves that fill the spinal column below the spinal chord
cervical enlargement
bulge in the spinal chord that goes to the arms from C3-T2
Lumbar enlargement
bulge in the spinal chord that goes to the legs from T9-T12
dorsal horn
gray matter, forms the back part of the
ventral horn
gray matter, forms the front part of the "H"
gray matter
made up of cell bodies and dendrites
white matter
made up of myelin and axons
dorsolateral sulcus
attachment of the dorsal root fibers (side, back)
ventrolateral sulcus
attachment of the ventral root (side, front)
dorsal root
nerves that come out of the back of the spinal chord
ventral root
nerves that come out of the front of the spinal chord
central canal
middle of the spinal column
dorsal ramus
where the dorsal root breaks off into a "Y"
ventral ramus
where the ventral root breaks off into a "Y"
dorsal root ganglion
bulby thing on the end of dorsal root
sensory neurons
transmit information from the body to the brain located in the dorsal root ganglia, have sensory ending which is sensitive to physical or chemical stimuli and they synapse in the spinal cord on a motor neuron or interneuron
posterior median sulcus
shallow groove at the back of the spinal column
motor neurons
efferent neurons which activate muscles of glands to produce some response
spinal reflex arc (Stretch reflex)
reflex that occurs with kneetap, simplest stimulus response system of the nervous system
group of neuron cell bodies within the CNS
mass of cell bodies outside the CNS
bundle of nerve fiber axons within the CNS, with functional and anatomical unity
bundle of nerve fiber axons outside of the CNS
(most of the nerves in the body), only found in the CNS, interconnect other neurons
lower motor neurons
efferent neurons whose cell body lies within the spinal chord
upper motor neurons
efferent fibers whose cell bodies are in teh upper brain levels and whose axons make up the descending pathways through the spinal cord
polysynaptic reflex
"stop extending, withdraw" extensors, flexor reflex
flaccid paralysis
muscle weakness and paralysis, lower reflexes
muscle etrophy
muscle weakness, deterioration
spastic paralysis
Muscle tightness or stiffness
an antatomical division of a large column of white matter
tracts of white matter
all on one side of the body
tract that crosses over
dura mater
outermost layer of the connective matter around the brain, very tough
second layer of connective matter around the brain, delicate web-like
pia mater
innermost layer of connective matter around the brain, "gentle mother" delicate, vascular
inflammation of the meningeal linings
meningeal linings
the connective layers around the brain
cerebrospinal fluid
fluid which "bathes" the brain, acts as a cushion and brings nutrients and removes waster from the brain tissue
choroid plexus
produces cerebrospinal fluid, inside the linings of the vetricles
excess of CSF
medulla oblongata
inferior-most segment of the brainstem, contains pyramids, olives, etc. ; cardiac center, vasocontrictor, respiratory center
created passageway (tube) to connect ventricles to different paths to drain excess fluid
made up of the medulla oblongata, the Pons, and the midbrain
"Bridge", holds centers associates with chewing, salivating, eye movements, hearing, and facial expression
holds cerebral peduncles, superior (visual reflexes) and inferior (auditory reflexes) colliculi
center of the brain, collection of nuclei
Functions of the thalamus
-relay point for all sensory info except smell
-where you begin to perceive pain and temperature (not localized)
-maintains cortical activity for sleep, waking, and arousal
-Imparting pleasantness or noxiousness to sensations (on a low, primal level)
fibrous material below the thalamus
functions of the hypothalamus
- metabolism, water balance
-autonomic nervous system
-expression of emotions
-sleeping, waking
-body temperature
-food intake
sex behavior
basal ganglia
made up of gray matter, Contains the Striate bodies and Internal Capsule, sit superiorly, laterally to the thalamus
Functions of the Basal Ganglia
-regulates complex motormovements such as posture, locomotion, balance, arm swinging while walking
-coordinating muscle groups
-decrease muscle tone (rigidity)
Substantia nigra
contains melanin, produces dopamine (destroyed with Parkinson's disease)
corpus striatum
the inside of the basal ganglia, contains caudate and lentiform nuclei
caudate nucleus
outside of the lentiform nucleus inside the basal ganglia
globus pallidus
lighter part of the lentiform nucleus
darker part of the lentiform nucleus
Parkinson's disease
disease that effects the sustantia nigra, basal ganglia, characterized by rigidity to muscle tone, resting tremor shuffling gait and "pill rolling" tendencies
Damage to the basal ganglia characterized by involuntary movement, sudden, jerky, purposeless movements
limbic system
Primative part of the brain that is related to cravings and addictions
major components of the limbic system
-cingulate gyrus
-mammillary bodies
-olfactory bulbs
Functions of the limbic system
-temperature regulation
-sexual functions
part of the limbic system related to memory and Alzheimer's disease
white matter of the cerebrum
include projection fibers, association fibers, commissural fibers
projection fibers
connect cortex with distant location outside of the cortex
types of projection fibers
corono radiata, internal capsule
association fibers
interconnect regions of the same hemisphere
types of association fibers
short fibers, long fibers (uncinate fasciculus, arcuate fascicuus, cingulum)
commissural fibers
connect location in one hemisphere with the corresponding location in the other
types of commissural fibers
corpus callosum, anterior commissure
the folds or convolutions of the cerebral cortex
the intervening grooves between the gyri on the surface of the cerebral hemispheres
cleft that separates large components of the brain
frontal lobe
1/4 of the cortex, biggest lobe of the brain, bounded posteriorly by central suclus, contains Broca's area
Parietal Lobe
Contains post central angular gyrus, center for comprehension of written material
Temporal lobe
Promary auditory area of the brain, contains Wernicke's Area
occipital lobe
Primary visual area of the brain
insular lobe
another name for the island or reil which contains the caudate nucleus and the lentiform nucleus
Broca's Area
area in the frontal lobe which is important for planning and initiating higher level thinking
Wernicke's Area
area in the temporal lobe that is important for the comprehension of speech
Gall phrenology
the theory that personality, characteristics can be distinguished based on the bumps on the brain
Motor area
cortex that focuses mainly on the mouth and hand
Sensory cortex
cortex that focuses mainly on the head and hand
atoms that have eithe lost or gained and electron
concentration gradient
a difference in the concentration of molecules on one side of a membrane from the concentration on the other side
the ease with which ions may pass though a membrane
passive mechanism
diffusion according to the concentration gradient
active mechanisms
ion pumps will move Na and K ions agianst the concetration gradient using energy
Sodium potassium pump
ions pumps using active mechanisms with energy from ATP (adenosine Triphosphate) to move Na and K ions against the concentration gradient
action potential
a change in electrical potential that occurs when the cell membrane is stimulated adequately to permit ion exchange
threshold level
a critical level which, if reached, will produce a sudden change in the membrane polarity for Na+ ions
when the critical threshold level is reached and the Na+ ions flood in and raise the intercellular potential to +30 to +50 mV
resting potential
30 times as many K+ ions inside as outside and 10 times as many Na+ ions outside as inside
absolute refractory period
the 1/2 of a second when the membrane cannot be depolarized again
K+ channels open up and K+ is going out of the intracellular space
relative refractory period
the interval immediately following absolute refractory period during which initiation of a second action potential is inhibited but not impossible.
a speech disorder arising from paralysis, muscular weakness, and discoordination of speech musculature
flaccid dysarthria
muscular weakness and hypertontia arising from LMN (lower motor neuron)damage
spastic dysarthria
inability to execute skilled movements and muscle weakness brought about by bilateral damage to UMN (Upper motor neuron) of the pyramidal and extrapyramidal pathways
ataxia dysarthria
damage to cerebellum or the brainstem vestibular nuclei causes loss of coordination and problems in reaching articulatory targets
hyperkinetic dysarthria
extraneous involuntary movement of speech muscles in addition to voluntary movement
hypokinetic dysarthria
lack of movement often caused by Parkinson's speech will be rushed with reduced duration and intensity
angular gyrus
in the parietal lobe, superior to temporal lobe, involved in a number of processes related to language, mathematics and cognition
Broca's aphasia
disfluent aphasia
Wernicke's aphasia
fluent aphasia
deficit in the motor programming of articulatory movements in the absence of muscular weakness or paralysis
conduction aphasia
good comprehension of speech and writing and fairy fluent speech but cannot repeat utterances which are heard
Dorsal funiculus
made up of fasciculus gracilis and fasciculus cuneatus
fasciculus gracilis
in legs conveys pressure, vibration, two point touch, kinesthetic proprioception (if you close your eyes, you know where your body is in space)
fasciculus cuneatus
in arms conveys pressure, vibration, two point touch, kinesthetic proprioception (if you close your eyes, you know where your body is in space)
Ventral spinothalamic tract
light touch
Lateral spinothalamic tract
pain, temperature
Dorsal and Ventral spinocerebellar tract
muscle tension, length, and stretch, damage impairs balance, walking