NEU 409 Exam 1 Flashcards
Coronal section:
divides structure into front and back portions
Sagittal section:
divides structure into left and right portions
Transverse section:
divides structure into upper and lower portions (also called horizontal/axial)
Superior (cranial):
from a high position, toward the head
Inferior (caudal):
from a low position, toward the tail
Anterior (ventral):
toward the stomach
Posterior (dorsal):
toward the back
Ipsilateral:
on the same side
Contralateral:
on the opposite side
Decussation:
cross over
Thalamus
Subthalamus
Hypothalamus
Epithalamus
Thalamus—relay station for sensory fibers
Subthalamus—regulates & coordinates motor function
Hypothalamus—regulates body functions (e.g., temperature)
Epithalamus—sleep/wake cycle regulation, optic reflexes
Grey VS White Matter
Gray matter in the brain and spinal cord is made up of cell bodies/soma.
White matter is composed of nerve fibers and myelin and AP
Nervous System Broken Up
NS
Sensory and Motor
Sensory:
- Somatosensory (touch pain)
- Visceral (general sensory stretch pain temp)
Motor:
- Autonomic (sympathetic and parasynthetic)
- Somatic (voluntary coordination muscle) Cranial Nerves + Spinal Nerves (voluntary= supply major muscles of the body)
Sympathetic Vs Parasympathetic
Sympathetic: fight or flight
- vital organs discharge energy
Parasympathetic: rest and digest
- restores energy
- involuntary = digestive system, heart rate, blood pressure, respiration, emotional reactions etc
Two Cell Types
Neurons Vs Glial
Neurons: located in CNS and PNS(cranial/spinal nerves) that communicate with nervous systems, organs, muscle, and glands.
Glial (glue) cells: diverse array of cells in the nervous system, roles include immune function, provide structural support, regulate the cellular environment.
Glial (glue) cells: CNS
Astrocytes:
Microglial cells:
Ependymal cells:
Oligodendrocytes:
Astrocytes: Provide structural support, Regulate nutrients and ions, Form scar tissue after injury, Form the BBB, Neurotransmitter uptake, Protect over exaltation of neurons, Maintain neuronal environment, Modulate breathing, and Repair/feed neurons.
Microglial cells: (immune cells) are small cells that phagocytize bacterial cells and cellular debris
Ependymal cells: (choroid) line the inside of ventricles and make CSF(cerebral spinal fluid) that cushion the brain and spinal cord protecting from any injury
Oligodendrocytes: form the myelin sheath in the brain and spinal cord
Glial (glue) cells: PNS
Satellite cells:
Schwann cells:
Satellite cells: provide nutrients and structurally support neurons while maintaining neuronal environment similar to Astrocytes
Schwann cells: produce myelin similar to Oligodendrocytes while being vital to regeneration of damaged peripheral nerve fibers
Neurons could be sorted into morphological groups
Unipolar:
Bipolar:
Pseudounipolar:
Multipolar cells:
Anaxonic Neuron:
Unipolar: Invertebrate neuron also touch and pain sensory neuron
have one process, an axon. (found in spinal dorsal roots-sensory)
Bipolar: Retinal ganglion cells and olfactory
has one dendrite and one axon attached to the cell body; are rarely found only in the special senses (retina & inner ear).
Sensory function
Pseudounipolar: tactile primary afferent of spinal & trigeminal nerves
two fused processes; sensory neurons outside CNS
Spinal & cranial nerves
Multipolar cells: motoneuron, pyramidal neuron, and purkinje(In cerebellum)
have many dendrites and one axon. The axon typically branches near its destination. These are motor and interneurons (found in CNS)
In cortex; corticospinal tract
Anaxonic Neuron: amacrine cell
Interneurons, communication between sensory or motor neurons
Afferent Communication VS
Efferent Communication
Afferent Communication: sensory signals from PNS to CNS (ascending) - body to brain
Efferent Communication: motor signals from CNS to PNS (descending) - brain to body
Neurotransmitters: Overall Function
Acetylcholine:
Glutamate:
Gaba:
Dopamine:
Epinephrine:
Norepinephrine:
Serotonin:
Overall Function:
Released from synaptic vesicles by presynaptic neuron (axon)
Bind to receptors on postsynaptic neuron (dendrite)
Can be excitatory or inhibitory A given neuron can produce several types of neurotransmitters
A given neuron can receive signals from several types of neurotransmitters
Acetylcholine: muscle contraction in PNS; memory
Mystingravious disease is an autoimmune disease which is slurred speech
Glutamate: excitation of CNS
Too much hurts motor system
Gaba: inhibits CNS activity
Huntington’s disease
Dopamine: motor control and brian reward system
Problem with dopamine is parkinsons
Epinephrine: excites heart; flight or flight response
Norepinephrine: attention, alertness, mood
Serotonin: mood and excites/inhibits nervous system
Neurons Compared To Other Cells:
Similarities:
Differences:
Similarities:
Have a membrane
Have a nucleus
Have a cytoplasm, mitochondria, & other organelles
Differences:
Have specialized projections
Communicate with each other through an electro-chemical process
Can be long, several feet at times
Channels Vs Pumps
Channels are passive
Pumps are active
Ion channels have proteins that make them have amino acids that have selective permeability and ions can be gated so they need pumps
Ion pumps – channels that require energy to actively move ions across the membrane
Work to maintain the concentration gradient
In the case of the sodium-potassium pump, it repeatedly transports three sodium ions out of the cell while drawing two potassium ions into it.
Channels and Gradients:
Ion movement occurs using (i.e., HOW they move)
Ion movement is driven by (i.e., WHY they move)
Ion movement occurs using (i.e., HOW they move):
- Ion Channels
- Ion Pumps
Ion movement is driven by (i.e., WHY they move)
- Electrical Gradient
- Diffusion/Concentration Gradient
Diffusion:
Net movement of ions from regions of high concentration to regions of low concentration
Differences in concentration known as concentration gradient
Electrical Potential of the Neuron:
Based on interaction between ions, cytosol, extracellular fluid and membrane
Two driving forces on ions to move
- Concentration gradient / diffusion
- Electrical properties
Electrical potential (voltage)
Electrical conductance (channels)
Resting Potential:
- At resting potential concentration of ions is kept constant through Na+/K+ pumps. When the threshold is reached, the Na+ gated channels are opened.
- Sodium Potassium Pump: 3 sodium out and 2 potassium in
- The electrical potential difference across the plasma membrane when the cell is in a non-excited state.
- Difference in voltage that exists between inside and outside of a neuron
- At rest, inside is more negative than outside
- Approximate resting potential inside neuron is -70 millivolts (mV)
Synaptic Integration:
- Neurons could be receiving thousands of synaptic inputs at any given time
- Must integrate all the signals to produce one simple output – action potential
- Synaptic potentials can be summed over time (temporal summation) or distance (spatial summation)
Transport:
Two Types of transport
Active: energy used
E.g., Pump needed to get water from A to D
In neuron, ion pumps use active transport
Passive: no energy used
E.g., simply open valve to get water from D to C
In neuron, ion channels use passive transport
Multiple Sclerosis (MS): Overview
Pathophysiology:
- Means “multiple scarring”
- Autoimmune disorder of unknown cause
- Primarily affects the CNS
- Myelin around axon is damaged
- No cure, but medications can suppress symptoms
- Myelin being attacked by antibodies is usually white females in their 30s and 40s
Pathophysiology:
Immune system cells break through the blood-brain barrier
Myelin is damaged, but in remission oligodendrocytes re-myelinate axons
Over time, oligodendrocytes become less effective at re-myelination
Common MS Symptoms:
Common early symptoms:
Common later symptoms:
Speech problems in MS:
Affects every person differently due to lesion locations
Common early symptoms:
Vision is blurry, colors are dull (optic neuritis)
Numbness, tingling in legs and/or face
Common later symptoms:
Difficulty walking and maintaining balance, feelings of vertigo
Fatigue
Vision problems (double vision, involuntary eye movements)
Muscle spasms in arms and legs, tremor
Slurred speech, difficulty controlling nasality in speech
Bladder and bowel issues
Speech problems in MS: Mixed dysarthria
Depends on where the lesions form first, if in cerebellum: scanning speech
Speech and swallowing: relapse
Different types of MS: four types
clinically isolated syndrome (CIS) - 5% gets worse but much faster progression
relapsing-remitting MS (RRMS) - 80% people
primary progressive MS (PPMS) - 10% gets worse and worse
secondary progressive MS (SPMS) - 60% doing well and then getting gradually worse
Why does MS relapse?
Diagnosis & Treatment of MS:
Inflammation in the CNS (immune response)
- MS is primarily involving the CNS, but some cases of PNS involvement as well
— Cranial nerve involvement in approx 11% of patients
- Relapse events result from person’s own immune system attacking their CNS
Diagnosis & Treatment of MS: can’t treat only modify
“Disease-modifying treatments” (e.g., immunosuppressants, steroids to reduce inflammation)
Physical therapy
Speech/Cognitive therapy (higher language skill) (cerebellum and frontal lobe)
Guillain-Barre Syndrome: mainly PNS
Similar to MS in that it is also an autoimmune demyelinating disease
HOWEVER, patients with Guillain-Barre Syndrome recover
Within weeks, months, or sometimes years
No known cause, but often after infection–rapid progression (over course of days or weeks) 4-15% can die from it but most recover
Rare disease–increased risk for young males; incidence of approximately 1-2 affected out of every 100,000 people per year
Can fix with therapy
Myasthenia Gravis:
Acetylcholine postsynaptic receptors: - autoimmune disease that destroys some of the postsynaptic receptors.
Sometimes it is due to an abnormal thymus gland.
Results in ptosis, facial weakness, flaccid dysarthria, dysphagia.
Amyotrophic Lateral Sclerosis (ALS; Lou Gehrig’s disease): neurodegenerative disease - everything is damaged in ALS
Motor neuron disorder
- “Withering” of upper & lower motor neurons (withering neuron)
- Atrophied muscle losing its bluck
- 10% of cases inherited; 90% unknown etiology
- Onset 40–60 years of age
- Most die within 3–5 years
- No cure
ALS
Early symptoms:
Progression of disease:
Early symptoms:
Twitching, cramping, or stiffness of muscles
Muscle weakness affecting an arm or a leg
Slurred and/or nasal speech
Progression of disease:
Full muscle paralysis
Exception of eye muscles
ALS - What about communication?
EEG speller–uses individual’s EEG patterns to predict letter selection
Currently NOT covered by Medicare/Medicaid.
Bulbar onset: Speech, breathing, and swallowing (1/3rd of the time) first before limbs
Spastic onset: limbs affected and later speech and swallowing
Spastic dysarthria ALS:
A 40-year-old woman with a three-week history of neurological symptoms including double vision, numbness in the left leg, dizziness, and gait imbalance was taken to a hospital where they examining neurologist noted the following:
· A reported history of a 10-day episode of blindness and pain involving the right eye about two years ago.
· Right optic disc paleness.
· Internuclear ophthalmoplegia (failure of abducting eyes in horizontal gaze).
· Decreased pinprick on the left lower abdomen down to the left knee.
· Signs of mild cerebellar dysfunction involving the right extremities with gait ataxia.
· Mild weakness of the left lower extremity.
· A mild form of scanned speech which the patient reported to increase in the afternoon; The articulators looked near normal.
· No sign of impaired cognitive or linguistic functions.
Brain MRI revealed multiple white matter hyperintensities (plaques), some perpendicular to the ventricles and one in the brain stem involving inferior cerebellar peduncle.
Question: Can you identify the associated slowly progressive neurological disease?
MS
● Double vision
● Numbness in the legs
● MRI shows white matter
A 45-year-old woman complained of feeling tired and weak in her legs after short walks or small amounts of motor activity. Her speech became unintelligible within a few minutes of talking, and she reported that she regularly cleaned her throat after eating, particularly after a liquid intake. She was seen by a neurologist who noted the following:
· Minor bilateral ptosis
· Incomplete lateral movement of the right eye medial strabismus.
· Expressionless and droopy face.
· Progressive and fatigable motor weakness.
· Progressive speech unintelligibility after continuous speaking.
· Signs of swallowing problems.
Based on the patient’s history comma age comma and progressive fatigue as well as improvement after and acetylcholinesterase drug, the neurologist suspected that this was a case of an autoimmune disorder in which the patient’s own immune system was attacking the postsynaptic receptor sites at the neuromuscular junction.
Question: The patient is suspected to suffer from which of the following diseases?
MG (Myasthenia gravis)
● The patients improvement after acetylcholinesterase was admitted
● Ptosis
A 28-year-old painter began experiencing weakness along with a tingling sensation in both his lower extremities while climbing a ladder at work in the morning and was sent home to rest. He was immobile by the afternoon as he could not get up and also found it difficult even to sit. By the next morning, he could not raise his arms and was taken to the ER where he reported an episode of respiratory infection about seven days ago. The examining physical noted the following:
· Weakness involving all four limbs with a greater involvement of the proximal than distal limbs
· Absent deep tendon reflexes
· Near normal responses to the sensations of pain, touch, and temperature
· Drooling from both corners of the mouth
· Inability to blow out the cheeks and protrude both lips
A speech therapy consultation revealed a dysarthric component largely because of imprecise articulation and reduced loudness. Laboratory work revealed an elevated level of proteins in the CSF. Looking at the history involving the earlier episode of the infection and the pattern of progressive weakness, the physician suspected this to be a case of post infectious neuropathy by demyelination which predominantly affected the motor functions of the proximal limbs.
Question: based on your understanding of the neuropathy in this and what we learned in class, can you relate this to the underlying disease process and explain the criteria for your diagnosis?
Guillain barre syndrome
● Autoimmune disease
● Young male
A 60-year-old man presented with the complaint that he was easily tired and needed rest even after a mild exertion. The neurologist who interviewed and examined the patient noted the following:
· A 6-month history of double vision
· Respiratory weakness with shallow breathing and limited vital capacity
· Progressive weakness including slurred speech after a brief period of physical activity
· Near normal muscular strength after rest
· No cognitive or linguistic deficit except speech intelligibility after exertion
· The neurologist noted that the administration of edrophonium (tensilon), an acetylcholinesterase inhibitory drug, resulted in improved physical strength of the patient. This led him to suspect a myoneural problem.
Question: how can you relate this motor weakness and speech unintelligibility after sustained physical activity to the suspected diagnosis?
MG
● An Acetylcholinesterase causes an increase in muscle strength by slowing the enzymatic destruction
A beginning SLP went to a grand round discussion, which focused on a patient who had profound aphasic symptoms disproportionate to the extent of the lesion displayed on a coronal MRI study. The SLP was asked what she could tell about this patient’s language dysfunctions. The SLP said that she wanted to see a different view of the brain before commenting.
Question: Which view of the brain would give the SLP a better clinical picture?
Sagittal view would give the best view of the brain in this case
A 45-year-old man presented to his family physician complaining of a several-month history of speech difficulty, with no other symptoms. A general medical examination was normal, and it was thought that his symptoms reflected anxiety. Two weeks later, he called to report that his speech was getting worse. He was referred for neurologic assessment, the results of which were judged normal, including speech. However, because of his complaint, speech pathology consultation was requested. Testing for myasthenia gravis (MG) was also ordered; the results were negative.
He was seen 2 weeks later for speech evaluation. He reported an approximately 5-month history of difficulty articulating words and felt the problem had worsened. Only within the past several weeks had his wife agreed that there was some “thickness” in his speech. During 4.5 minutes of continuous reading, there was no dramatic deterioration of voice or speech, ruling out MG. Several days later an EMG revealed fasciculations and fibrillations in the left upper extremity, left tongue, and bilateral thoracic paraspinal muscles.
What could be the possible neurodegenerative disease and what helped you decide?
ALS
● Early symptoms of ALS; speech
Fill In the blank
The BLANK contribute to the natural recovery process by ingesting and removing cellular debris
microglial cells
Fill In Blank
The BLANK, a multilayered lipid material not only protects nerve fibers by insulating them but also regulates the speed of AP
Myelin Sheath
Fill In Blank
The point Contact Between 2 Neurons Is Called BLANK
Synapse
Fill In Blank
The conditioning which antibodies attack body own normal tissues is called an BLANK
MS autoimmune disease
Fill In Blank
Abnormalities of cytoskeletal structures in the form of tangles, and subsequently, and subsequently, the reduced intracellular protein transfer has been associated with BLANK
Alzheimer’s
Fill In Blank
The BLANK Cells Produce CSF in BLANK
Ependymal
CNS
Ventricles
Alternative methods of communication used by persons with ALS
1.Eye-tracking devices—how does it work? - sees where eyes moved bc not parlysed - funded by medicare
2.EEG speller—how does it work? Picking up thoughts from brain and puts a cap on head picking up electrical signals
3. Issues with funding for communication devices - devices expensive
Dysphagia
swallowing problem
