Neurology Flashcards
gyrus
folds of cerebrum
brain damage due to lack of O2 time
4 minutes
Cerebral peduncles are
Large tracts that contain axons of motor neurons from cerebrum to rest of brainstem and spinal cord
Lateral gray horn only in
thoracic and upper lumbar segments
****autonomic motor only located in lateral gray horn
Spinal Reflex vs cranial reflex
simple vs occurs in brain stem
Ganglion cluster
cluster in PNS
Pons aka
bridge
Nodes of Ranvier
Gaps in myelin along axon
Spinal root definition
2 bundles of axons connect each spinal nerve to cord
Axon Terminals aka
Synaptic Vesicle
S Division
P Division
S=Sympathetic
P=parasympathetic
Spinal Cord description
Connects to brain surrounded by vertebral column; 100 million neurons
Ependymal
Form CSF in ventricles
Multipolar Structure
most common; several dendrites one axon
S and P have what effects
antagonistic
Cranial nerves
12 pairs; I-XII; part of PNS and emerge from base of brain
Brain stem contains
continuous with spinal cord contains medulla oblongata, pons and midbrain
SNS motor pathway
one neuron from CNS to effector
SNS sensory pathway
3 cell bodies
- dorsal root ganglion
- spinal cord or brain stem
- thalamus
2 spinal white matter columns
Sensory tract (ascending) Motor Tract (descending)
primary somatosensory area
postcentral gyrus
Diseases destroying myelin sheaths (2)
multiple sclerosis
Tay-sechs
What is called the emotional brain?
the limbic system
Somatic Nervous System
Motor:
Sensory:
Motor: Voluntary control
Sensory: Senses
What helps execute skilled motor movements?
Cerebellum
What cell produces CSF?
ependymal cells
sacral plexus supplies
buttocks, perineum, most lower limbs
Astrocyte function
form blood brain barrier
posterior horn has what neurons
sensory neurons
Ganglia (system and description )
PNS/small masses of neurons
Brain matter (gray and white)
Gray matter in thin cortex surrounds white matter
Subarachnoid space
between arachnoid and pia mater; filled with CSF
Enteric Nervous Systems
Monitors chemical changes in GI tract;
Regulate contractions, acids, endocrine cells
Unipolar
Fused dendrite and axon; sensory of spine
Action Potential aka
Nerve impulse; allows for neuron communications
What cell produces myelin around PNS neurons?
Schwann Cells
2 spinal cord grooves
anterior median fissure
posterior median fissure
Spinal cord 2 enlargements
Cervical: upper limbs
Lumbar: lower limbs
Pons connects:
connects left and right side of cerebellum
Pineal gland secrets
melatonin
Nerve wrap layers (4)
- endoneurium: wraps axons
- fascicle: group of axons in bundle
- perineurium : wrap fascicles
- Epineurium: covers entire nerve*
Action Potential requires
Resting membrane
ion channels
Amino Acids (4)
glutamate, aspartate, gamma aminobutyric, glycine
Neurons function
electric/ unique functions
primary motor area
precentral gyrus
Somatic motor pathway route
axon ventral root spinal nerve muscle voluntary movements
Pia Mater
Inner layer; thin and delicate; adheres to spina cord and brain
3 basic neurons
sensory neurons (afferent)* interneuron moto neuron (efferent)*
anterior spinothalamic tract controls (2)
light touch sensation
deep pressure sensation
lumbar plexus supplies
abdominal wall, external genitals parts of lower limbs
What coordinates reflex center for the eye, head movement and auditory relay?
Cerebellum
Cerebrum
largest and most superior part
“X-Men”
Cell Body contents (3)
Nucleus cytoplasm organelles
Sensory Neuron
Afferent/Conveys info to CNS
lobes of cerebrum hemispheres
frontal parietal temporal occipital
Microglia
Protects CNS cells from disease
parietal lobe and frontal lobe separated by
central sulcus
Neuro transmitters (5) AAMNN
ACh amino acid modified amino acid norepinephrine nitric oxide
Regeneration of PNS neurons
Axons and dendrites can be repaired if cell body is intact and Schwann Cells are functional
Parasympathetic cell bodied cranial nerves + segments
3
7
9
10
S2-S4
Oligodendrocyte
Produce myelin in CNS
What cell produces myelin around the CNS neuron?
Oligodendrocytes
Where is CSF produced
choroid plexuses
located in ventricles in the brain
Components of synapse
presynaptic neuron (sending) Synaptic cleft (space between) post synaptic neuron (receiving neuron)
right hemisphere of brain
pattern recognition, emotional content, sight, sound, taste, smell
Gray Matter definition
Lacks myelin
Axon
conducts away from cell body/ cone-shaped Axon Hillcock
Effectors act on
Muscles and Glands
Myelination
insulates axon and speeds up impulses; increases from birth to maturity
Rest and Digest
“SLUDD”
salivation lacrimation urination digestion defecation
White matter definition
Primarily myelinated axons
Spinal nerve pair breakdown
8 cervical 12 thoracic 5 lumbar 5 sacral 1 coccyx
Pons associated with which cranial nerves
5-8
diencephalon
superior brain stem contains thalamus, hypothalamus, and pineal gland
Neuroglia (4)
Support nourish and protect neurons
critical for homeostasis of ISF around nucleus
cells smaller but many more
make up 1/2 volume of the CNS
Spinal Cord White Matter
Tracts act as highways
Meninges layers
Dura
Arachnoid
Pia
Regeneration of CNS
very limited; inhibited by neuroglia
3 PNS subdivisions
EAS
SNS
ANS
ENS
left hemisphere of brain
speech, writing, numerical, science, reasoning
What AREA* regulates breathing and speech muscles
Broca’s Speech Area
Enteric Plexus (system and description)
PNS/ located in GI tract
hypothalamus
important for homeostasis
controls pituitary gland and hormone production*
Medulla oblongata white matter
contains all sensory and motor tracts between spinal cord and brain
stimulus charge
-55 microvolts
Dura Mater
Outer layer; tough and dense; extends to S2; covers brain
Brain description
Surrounded by skull; 100 Billion neurons
Satellite Cells
Support neurons in PNS ganglia
Posterior Root (grey H)
(sensory) Sensory axons supply to CNS
AP phases
Stimulus
Depolarizing Phase (rising)
Repolarizing Phase (return to resting)
Hyperpolarization
brain blood supply stats
2% body weight; 20% O2 supply
Medulla oblongata associated with what cranial nerves
8-12
sulcus
shallow grooves of cerebrum
3 neuroglia functions
do not generate or conduct impulses
s/n/p neurons
multiply to fill space formerly occupied by neurons
One sympathetic preganglionic axon can synapse how may postganglionic neuron cell bodies
20
Saltatory conduction definition
nodes of Ranvier allow impulses to leap from one node to the next
*faster form
brachial plexus supplies
upper limbs, some neck, shoulder muscles
Autonomic Nervous System
Motor:
Sensory:
Motor: Involuntary
Sensory: to Visceral Organs
Bundle of Axons (2)
Nerve-PNS
Tract-CNS
Motor neuron
Efferent/ convey info away from CNS to muscle &glands
Sensory Receptor (system and function)
PNS; Monitor environment changes
3 regions of diencephalon
thalamus
hypothalamus
pineal gland
ACh (and function)
Acetylcholine
PNS/Stimulatory to skeletal muscle and inhibitory to cardiac muscle
Anterior Root (grey H)
(motor) Axons of motor neuron from CNS to effector
3 Neuron Structural Classes
Multipolar
Bipolar
Unipolar
6 neuroglia types
“A-MOSES”
astrocytes oligodendrocytes microglia ependymal Schwann cells Satellite cells
Midbrain connects…
Pons to diencephalon
Autonomic Nervous System motor pathway
two neurons from CNS to effector
Pons contains which tracts?
ascending(sensory) and descending (motor)
Bipolar Structure
One dendrite one axon; specialized
descending tract example
corticospinal tract (CST)
Spinal Cord Gray Matter
Receives and integrates info for reflexes
3 factors increasing rate of conduction
myelin
large diameter
warm nerve fibers
Little brain aka
Cerebellum
Longitudinal fissure
divides cerebrum into right and left hemispheres
Spinal cord matter (white and gray)
white(tracts) surround the gray H (butterfly)
Somatosensory association area
located in postcentral gyrus
storage of memories of past sensory experiences
Dendrite
Carry Impulses to cell body/ branches
Cell body in CNS
Nucleus
Interneuron
Integrates info/ analyzes and stores info
What network of nerves are located in the GI tract?
enteric
Arachnoid Mater
middle layer; extends into subarachnoid space
2 classes of neurologic tissue
Neuron
Neuroglia
lateral spinothalamic tract
pain
hot vs cold
Spinal nerves
31 PAIRS serving each part of the body
Medulla oblongata location
forms inferior part of brain stem
Schwan Cells
Produce myelin around PNS
Epidural Space
Fat between vertebrae and dura mater
PNS contents
Cranial Nerves Spinal Nerves Ganglia Enteric Plexus Sensory Receptors
Continuous conduction definition
in unmyelinated axons currents flow across adjacent portions of plasma membrane
Spinal cord lengths
16-18” from medulla ob. to L2
Responsible for conscious proprioception
posterior column- medial lemniscus pathway
modified amino acids (3)
Norepinephrine, dopamine, serotonin
Coordinates muscular movement
Red nuclei of midbrain
Midbrain associated with what cranial nerves?
III and IV
Autonomic controls voluntary or involuntary
involuntary
Medulla oblongata gray matter + 2 important features
contains nuclei where neurons form synapses
- Cardiovascular center regulates rate and force of the heart and diameter of vessels
- Medullary rhythmicity regulates breathing
Lateralization
brain controls the opposite of the body
What nerves carry 80% of P impulses to viscera?
Vagus
CN X
“DMX/CNX”
Neuron 4 parts
Cell body
Dendrite
Axon
Axon Terminal
Circle of Willis
circulatory anastomosis supplies blood to brain and surrounding areas via 2 carotid arteries
Neuroglia function
Support, nourish and protect neurons
resting potential charge
-70 microvolts
cervical plexus supplies
posterior head, neck, upper shoulder and diaphragm
Spinal cord white mater
myelinated axons with 2 columns
anterior horn
motor neurons
thalamus
major sensory relay center; contributes to motor functions
Nervous system tasks (7)
smell touch temp speech remember body movement operation of internal organs
ANS subdivisions
Sympathetic and Parasympathetic
CNS contents
Brain and Spinal Cord
3 neurons in SNS pathway
distal root ganglion
brain stem or spinal cord
thalamus
Somatic Sensory Pathway example
Posterior column - medial lemniscus pathway senses
Anterior spinothalamic tracts 2 tasks
light touch
deep sensation
Lateral spinothalamic tract
2 tasks
pain and temp
What tests for proprioception?
Romberg
Upper abdominal reflex vertebrae
T8-T10
Lower Abdominal Reflex Vertebrae
T10-12
Cremasteric reflex vertebrae
T12 L1 L2
Deep Tendon Bicep Vertebrae
C5 C6
Plantar vertebrae reflex
L5 S1 S2
Triceps reflex
C5 C7 C8
Patellar reflex vertebrae
L2-L4
Achilles reflex vertebrae
S1 S2
DTR 4
very brisk/hyperactive
DTR 3
brisk/ slightly hyperactive
DTR 2
active/normal
DTR 1
sluggish/diminished
reabsorbs CSF
arachnoid villi
One antibiotic that permeates blood brain barrier
ceftriaxone
Tract for Deep Sensation and Light Touch
AST
Anterior Spinothalamic Tract
Tract for Px and Temp
LST
Lateral Spinothalamic Tract
CN in Pons
CN 5-8
Brain Blood Barrier allows what to pass
Lipid soluble and : O2 CO2 EOTH Anesthesia