Neuro Flashcards
what is the network of nerves located in the gastrointestinal tract?
Enteric Motor Neurons (involuntary) in enteric plexuses
how many spinal nerve pairs do we have and name each category?
31 spinal nerve pairs
- 8 pairs in the cervical
- 12 pairs in the thoracic
- 5 pairs in the lumbar
- 5 pairs in the sacral
- 1 in the coccygeal
what are the motor neurons that carry neural impulses away from the CNS and toward muscle to cause contraction?
efferent
what is the name of the sensory neurons that carry impulses from the sensory stimuli toward the CNS?
afferent
structural classes of a neuron
unipolar
bipolar - special senses
multipolar- most common in the body
what supports, nourishes, and protect neuron and is critical for homeostasis?
neuroglia
what cell produces myelin around the pns neuron
schwann cells
what cells produce myelin around the CNS neuron?
oligodendrdrocytes
what cell produces CSF?
ependymal cells
What cell forms the blood brain barrier
astrocytes
what is the bundle of axons in the PNS called?
Nerve
what is a bundle of axons in the CNS called?
Tract
what nervous system includes cranial nerves, spinal nerves and sensory nerves??
PNS
what nervous system controls thoughts emotions and memories
central nervous system
what nervous system conveys information from sensory receptors in the head, body wall and limbs and from the receptors for special senses (vision, hearing, taste and smell) to CNS and conduct motor impulses from the CNS to skeletal muscles
somatic nervous system
what nervous system conveys sensory information in visceral organs (stomach/lungs) to CNS and conduct motor impulses from CNS to smooth muscle, cardiac muscles and glands?
autonomic nervous system
what nervous system is called brain of the gut, monitors chemical changes in the GI tract, stretching walls, regulate acid secretion and endocrine cell secretions?
enteric nervous system
what are the meningeal layers?
dura mater
arachnoid mater
pia mater
what is the most outer meningeal layer?
dura mater
what is the middle meningeal layer and resembles spider web?
arachnoid layer
what is the inner, thin and delicate and adheres to surface of the spinal cord and brain?
pia mater
it also contains numerous blood vessels(
what is the name of the space cerebral spinal fluid travels?
subarachnoid space
what space helps protect and cushion and is between the vertebrae and dura mater?
epidural space
what is the name of the two spinal cord grooves?
anterior median fissure
posterior median sulcus
what axons does the posterior (dorsal) root contain?
sensory axons (afferent)
(which conduct nerve impulses from sensory receptors in the skin, muscle and internal organs into the central nervous system)
what axons does the Anterior (ventral) root contain?
motor neurons (efferent)
which conduct nerve impulses from the CNS to effectors
what axons does the posterior grey horn contain?
sensory neurons
what axons does the anterior(ventral) grey horn contain?
somatic motor neurons that provide impulses for contraction of muscles
what axons does the lateral gray horn contain?
autonomic motor neurons that regulate the cardiac muscle, smooth muscle and glands
only present in the thoracic and upper lumbar segments
what tract conducts nerve impulses toward the brain?
sensory tract
Example: spinothalamic
what tract conducts nerve impulses away from the brain
motor tracts
example: corticospinal tract
what are the two types of reflexes?
spinal - simple reflex arc - patellar reflex
cranial - occurs in brainstem - gag reflex
what plexus supplies the upper limbs, some neck and shoulder muscles?
brachial plexus
examples: radial nerve, ulnar nerve and axillary nerve
what plexus supplies posterior head, neck, upper part of the shoulders and the diaphragm
cervical plexus
example: phrenic nerve (C3, 4, 5)
what plexus supplies abdominal wall, external genitals, and parts of the lower limbs
lumbar plexus
example: femoral nerve (L2-L4)
what plexus supplies buttocks, perineum and most of the lower limbs?
sacral plexus
example: sciatic nerve (L4 -S3)
what percentage of oxygen does the brain require?
requires 20% of the bodies oxygen supply
what major vessels compose the circle of willis?
internal carotid arteries
where is CSF produced?
choroid plexuses located in the brain
Choroid plexus which is specialized networks of capillaries in the walls of ventricles
what are the components of the brain stem?
medulla oblongata (inferior part of the brain stem; continuation of the spinal cord)
pons (“bridge that connects the medulla to the midbrain and above)
Midbrain (connects pons to diencephalon)
what are the components of the diencephalon?
thalamus (major sensory relay center)
Hypothalamus (important for homeostasis)
Pineal Gland (part of the endocrine system)
what is called “little brain”
cerebellum
what regulates breathing, heart rate and force and contains cranial nerves VIII-XII
medulla
what is called the “bridge” and connects the left and right side of the cerebellum and contains CN V-VIII
pons
what coordinates reflex center for the eye, head movement and auditory relay?
midbrain
what controls relay center, motor functions and consciousness
Thalamus
what controls homeostasis, pituitary gland, hormone production, body temperature, circadian rhythm?
hypothalamus
what secretes melatonin and promotes sleep?
pineal gland
what controls smooth/coordinate skeletal muscle contraction, skilled motor activities, posture and balance
cerebellum
what is called the emotional brain, plays a roll in pain, pleasure, anger, and affection?
the limbic system of the cerebrum
name all the CN that only have sensory function
CN I, II, VIII
name the CN that only have motor functions
CN III, IV, VI, XI, XII
what CN tests for superficial pain and touch sensation of the face and ability to clench the teeth
CN V : trigeminal
what cn test for hearing and lateralization of sound?
CN VIII, Vestibulocochlear
what three neurons are in the somatic sensory pathway?
cell body #1 is in the dorsal root ganglion
cell body #2 is in the spinal cord or the brain stem
cell body # 3 is in the thalamus
what are the two examples of the somatic sensory pathway?
pain stimuli
mechanical stimuli
what spinal tract pathway test for superficial pain and temperature
lateral spinothalamic tract
what spinal tract pathway test for superficial touch and deep pressure
anterior spinothalamic tract
what spinal tract pathway tests for vibration, deep pressure, position sense, stereognosis, point location and two point discrimination?
posterior column- medial lemniscus pathway
what spinal tract pathway tests for rapid rhythmic, alternating movements, voluntary movements, DTR and Plantar reflex?
corticospinal tract
what spinal tract pathway test for posture, romburg, gait and instinctual motor reactions
Reticulospinal (descending tract)
what reflex controls spinal nerve T8, T9, and T10
upper abdominal
what reflex controls spinal nerve T10, 11 and 12
lower abdominal
what reflex controls spinal nerve T12, L1 and L2
Cremasteric
what reflex controls spinal nerve C5 and 6
Bicep (DTR)
Brachioradial (DTR)
what reflex controls spinal nerves L5, S1 and S2
Plantar
what reflex controls spinal nerve C6, 7 and 8
Triceps
what reflex controls spinal nerve L2, 3 and 4
Patellar
What reflex controls spinal nerve S1 and S2
Achilles
What does a DTR score of 1+ mean
minimal (sluggish or diminished)
What does a DTR score of 2+ mean
Normal (active/ expected response)
What does a DTR score of 3+ mean
Brisk (More than expected, slightly active)
what does a DTR score of 4+ mean
Very Brisk (Hyperactive, with intermittent or transient clonus)
What does a DTR score of 0 mean
Absent
what are the two neurons in the somatic motor pathway
upper and lower motor neurons
what are the subdivisions of the autonomic nervous system
sympathetic
parasympathetic
name the two neurons in the sympathetic division pathway?
preganglionic
postganglionic
what autonomic nervous system division increases HR, BP, dilate pupils, dilate airway, dilate vessels of the skeletal muscles, heart, liver and adipose tissue
fight or flight (sympathetic)
What does the acronym SLUDD mean?
Salivation Lacrimation Urination Digestion Defecation
(Mainly the parasympathetic)
Diagnosis for:
Pain on the right side of the head with some lacrimation.
Neuro exam in unremarkable
Cluster headache (Due to the lacrimation)
TX: Inhaled 100% oxygen fir 15 minute
- sumatriptan SubQ initial 6 mg do not exceed two 6mg injections in 24 hours
- Zolmitriptan Oral 2.5 mg no more than 10mg in 24hours may repeat every 2 hours as needed for pain
Sailor immediately falls to the floor and goes rigid. Right after he starts experiencing jerking, which lasts about 90 seconds, then he remains unresponsive and goes flaccid.
When he gains consciousness, he complains of fatigue and a headache. What condition did this sailor more than likely experience
Generalized Seizure- Tonic-clonic (AKA grand mal)
Treatment for active seizure:
Clear the room and maintain airway
Diazepam 5mg iv/im every 5-10 minutes do not exceed 30 mg
Suspicion of a drunk sailor due to slurred speech, difficulty understanding others and imbalance.
- unremarkable neuro exam
- HPI: patient takes HCTZ QD and states he felt weird and not him self this morning but went into work anyways. What is most likely the diagnosis for this patient
ischemic stroke
- do not lower blood pressure acutely as it may be the only thing maintaining adequate perfusion. UNLESS PRESSURE IS ABOVE 220/120
TX: Medication - Aspirin 325 mg and medevac
Sailor presents with 9/10 headache
- around the head and squeezing
- going through divorce and extremely tired with work
- unremarkable neuro exam
- neck and back of head tender to palpation
tension headache
-Treatment: NSAID ibuprofen 400-800 mg po q 4-6 hours max 2400mg or naproxen 250-500 mg po q12hrs
Tylenol 325-1000 mg po q 4-6 hours, max 4 grams
Sailor drunkenly fell, witness states he had alot to drink and got into a fight then was knocked unconscious.
- Woke: couldnt remember what happened and was confused
- Neuro exam: inability to focus, slurred speech, stare and disorientation
Concussion
TX: MACE within 48 hours
- 24 hours mandatory rest with 2 hour checks
Patient reports with headache.
- Worst headache of my life
- neck pain
- N/V x2
- focal deficits noted
Subarachnoid hemorrhage
TX plan: MEDEVAC
- bedrest
- analgesic = Tylenol
- no drugs that can lead to anticoagulation
Tackled during a soccer game and audible scream after falling on neck.
- neck pain
- numbness spreading down arms and legs
- step off at C5 and swelling
- spinal cord injury
TX plan: MEDEVAC ABC's first -C-collar ASAP - insert a foley catheter - maintain oxygenation and B/P - may require intubation if resp compromise
MO PERMISSION = Methylprednisolone 125 mg im/iv q 4-6 hours
Patient reports feeling ill
- sister feels the same
- headache, light sensitivity, neck pain, chills, skin rash, generalized pain.
- Exam reveals: Nuchal rigidity, neuro deficits, burdzinkis sign and kernigs is postive
- Temp: 103.5F
What is the treatment and prophylaxis of this?
Meningitis
This is a Medical emergency, almost 100% fatal
TX: Ceftriazone 2mg IV q12hrs (antibiotic that can cross blood brain barrier)
Prophylaxis:
- Treat the exposed crew with Ciprofloxacin 500mg PO x1
- ensure vaccinations are current (meningococcal, s. penimonieae and H influenza)
- mask patient and close medical personnel
CC: Feeling sick
PmedHX: Ear infection about a week ago
Sx: numbness in face, drooling, tearing of eye, blinking and inability to drink water
PE: CN VII deficit and unable to raise eyebrows or make forehead folds.
What is the dx? and what is the best treatment?
Bells palsy
- eye protective measures (if inadequate closure of eye)
-MEDICATION: Prednisone 60mg PO daily for 7 days then 5 day taper
severe is treated with: Valacyclovir 1000 mg 3 times daily for 7 days
what is the treatment for psychogenic nonepileptic seizures?
Cognitive behavioral therapy
what is a hemorrhagic stroke?
Bleeding INTO the brain
What is an Ischemic stroke?
BLOCKAGE of a blood vessel causing lack of cerbral blood flow leading to ischemia
What are the two subtypes of ischemic stroke?
Transient ischemic attack
Cerebral Vascular accident
what is the most common type of stroke
ischemic
what is the difference between TIA and CVA
Transient = transient episode of neurologic disfunction caused by focal brain, spinal cord or retinal ischemia without acute infarction
CVA = Neurological dysfunction WITH infarction (tissue death) of the central nervous system tissue
What occurs within the precentral gyrus?
Primary motor area, skeletal muscle (somatic), all intended movements
Where does learned sequences of movements occur
Frontal lobe (somatic sensory)
what is an efferent tract
corticospinal
what is an afferent tract
spinothalamic (axons go from spinal cord to thalamus)
posterior column- medial lemniscus is also an afferent tract
Conscious proprioception occurs where?
PCML (posterior column - medial lemniscus )
Pain and temperature is controlled where
lateral spinal thalamic tract
Which cranial nerves have pons nuclei?
CN V- VIII
What is the definition of a seizure?
an abnormal, excessive, hypersynchronous discharge from an aggregate of CNS neurons
nuclei in the medulla cranial nerves
CN VIII- XII
what is a focal seizure without impaired consciousness or formally known as complex partial seizure
does not involve the whole brain
i.e. only one part of the brain is affected
what is status eplilepticus
when a single seizure last more than or equal to 5 minutes or 2 or more seizures occur causing an incomplete recovery time
How is the only way to truly diagnose a seizure
video EEG
if an EEG shows no changes in electrical activity, what type of seizure is this?
Psychogenic nonepileptic seizure
Where do disk herniations usually occur
L5 through s1
What type of hemorrhage is this? immediate loss of consciousness after a significant head trauma, “lucid interval” with recovery of conciousness
Epidural hemorrhage
between the dura mater and the skull
what is more common than an epidural hemorrhage, often occurring in the elderly, ETOH abusers and those on anticoagulants? It may sometimes occur with impact
Subdural hemorrhage
between the dura mater and arachnoid mater
A patient reports hearing a “thunder clap” and then immediately having the worst headache of his life.
Past social history includes heavy alcohol use, cocaine and smokes a pack of cigarettes a day.
Subarachnoid hemorrhage
(bleeding is high pressure and into subarachnoid space which normally carries CSF)
(Usually rupture of blood vessel aneurysm)
If a patient reports to medical following a severe blow to the head and during the MACE exam reports that this is her second mTBI/Concussion in 12 months, what is the rest period
RTD delayed for an additional 7 days following symptom resolution
what can be caused from severe compression of the spinal cord and is considered a surgical emergency
Cauda Equina syndrome
define sciatica
Electrical shock like pain radiating down the posterior aspect of the leg, often below the knee
What is the most common level of herniation causing decreased strength in foot dorsiflexion, toe extension, foot inversion or eversion
L5
what is carpal tunnel syndrome
an entrapment neuropathy caused by compression of the median nerve between the carpal ligament and other structures within the carpal tunnel
How do you diagnose carpel tunnel
tineal or Phalen’s sign is enough to diagnose
also diagnosed with ultrasound and nerve conduction studies
What is the clinical presentation of bells palsy
abrupt onset of unilateral face paralysis
pain about the ear
face feels stiff and pulled on one side
may be ipsilateral restriction of eye closure and difficulty with eating
bells phenomenon (upward rolling of the eye on attempted lip closure)
how will you differentiate between a stroke and bells palsy
stroke = no paralysis of the forehead
intake forehead muscle tone suggest a stroke and not bells palsy
what are the gaps in myelin along the axon
nodes of Ranvier
what is the depolarization phase
voltage gated Na+ channels open
membrane potential rises and become positive
what is the repolarization phase
Voltage gated K+ channels open, more K leaves cell
membrane potential is returned to resting value
Brain neurons deprived of oxygen for over ____ minutes may lead to permanent damage
4 or more minutes
Blood brain barrier protect the brain cells from harmful substances and pathogens but what does it allow the passage of?
Lipid soluble such as O2, CO2, Alcohol, and anesthesia
where is CSF absorbed?
slowly reabsorbed into the blood through the ARACHNOID VILLI
The fold of the cerebrum are called
Gyri (gyrus)
the shallow grooves of the cerebrum are called
sulci (sulcus)
What regulates breathing and speech
brocas speech area (in the frontal lobe close to the lateral cerebral sulcus)
the autonomic nervous system motor pathway has how many neurons from CNS to the effector?
2 neurons (Somatic nervous system motor pathway has one)
preganglionic neurons contain what receptors?
ACh
what supplies abdominal viscera in the prevertebral gangila
celiac, superior and inferior mesenteric ganglia
what cranial nerve carries 80% of all Parasympathetic division nerve impulses?
Vagus CN X
sympathetic division releases what
epinephrine/ norepinephrine
what is the heel to toe gait assessment used for
exaggerate any abnormal gait
What is the function of Neuroglia?
Provide support, nourishment and protection
CRITICAL FOR HOMEOSTASIS OF INTERSISTITAL FLUID AROUND NEURONS
Which structural class of neuron is found in the retina of the eye and has one dendrite and one axon?
Bipolar (special senses)
What structural class of neuron is the most common type in brain and spinal cord?
Multipolar
What structural class of neuron is sensory neurons of spinal nerves
Unipolar (fused dendrite and axon)
What is a cluster of cell bodies in the PNS
Ganglion
What is a cluster of cell bodies in the CNS
Nucleus
What is a bundle of axons in the PNS
Nerves
What is a bundle of axons in CNS
Tract
Which ascending tract is associated with superficial pain and temperature test
Lateral spinothalamic
Which ascending tract is associated with superficial touch and deep pressure
Anterior spinothalamic
What ascending tract is associated with vibration, deep pressure, position sense, sterognosis, point location and two point discrimination
Posterior column
What is associated with proprioception
Anterior and dorsal spinocerebellar
Which descending tract is associated with rapid rhythmic movement, voluntary movement, DTR, and plantar reflexes
Lateral and anterior corticospinal
What is associated with posture and Romberg, gait and instinct motor reactions
Medial and lateral reticulospinal
What are the descending tracts?
Corticospinal (lateral) = limbs
Corticospinal (anterior) = Abs (core)
Reticulospinal = reflex
What are the ascending tracts?
Spinothalamic (lateral) = superficial pain and temperature
Spinothalamic (anterior) = superficial touch and deep pressure
Spinocerebellar = proprioception
Posterior column ( vibration, deep pressure, position sense, sterognosis, point, two point)
