Sensory Function Disorders Flashcards
Discuss the pathophysiology of pain and distinct types of headaches. Differentiate causes and manifestations of selected disorders of the eye including conjunctivitis, cataracts, glaucoma, retinopathy, retinal detachment, and macular degeneration. Describe causes and manifestations of selected disorders of the ear including otitis media and hearing loss. Discuss the pathophysiology and manifestations of the vestibular system including vertigo, motion sickness, and Meniere disease.
1
Q
What are the four steps of the pain pathway?
A
Transduction → Transmission → Perception → Modulation
2
Q
What is transduction in the pain pathway?
A
It’s when injured tissues release chemicals (e.g., prostaglandins, bradykinin, histamine) that activate nociceptors
3
Q
What fibers carry pain signals during transmission?
A
A-delta fibers (sharp, fast pain) and C fibers (dull, slow pain)
4
Q
What role does the thalamus play in pain perception?
A
It relays pain signals to the cortex and limbic system for interpretation and emotional processing
5
Q
What is modulation in the pain pathway?
A
The brain reduces or enhances pain through descending pathways using endorphins, serotonin, and norepinephrine
6
Q
what is the main function of the somatosensory cortex?
A
sense touch, temperature, body position, and pain
7
Q
What is the role of first-order neurons in the pain pathway?
A
They detect noxious stimuli via nociceptors in the periphery and transmit the signal to the spinal cord.
8
Q
Where are the first-order neuron cell bodies located?
A
In the dorsal root ganglion (DRG) of spinal nerves.
9
Q
What do second-order neurons do in the pain pathway?
A
They receive signals from first-order neurons in the spinal cord and transmit them up the spinothalamic tract to the thalamus
10
Q
Where are second-order neurons located?
A
In the dorsal horn of the spinal cord.
11
Q
What’s special about second-order neurons in referred pain?
A
They receive converging input from both visceral and somatic first-order neurons, leading to mislocalized pain.
12
Q
What do third-order neurons do in the pain pathway?
A
They transmit signals from the thalamus to the somatosensory cortex, where pain is consciously perceived and localized.
13
Q
Where are the third-order neuron cell bodies located?
A
In the thalamus
14
Q
What brain regions receive input from third-order neurons?
A
Somatosensory cortex (localization), limbic system (emotional response), and frontal cortex (cognitive processing).
15
Q
what is pain perception?
A
bodies interpretation of pain
16
Q
what is pain threshold?
A
the point a stimulus is percieved as pain
pretty consistent
17
Q
what is pain tolerance?
A
maximum intesnity of duration of pain a pt can endure before wanting the pain treated
unique, varies greatly
18
Q
as pain threshold increases, pain tolerance ______
A
increases
19
Q
What is somatic pain?
A
Pain from skin, muscles, joints, bones, or connective tissue
20
Q
Why does somatic pain occur?
A
To protect the body by prompting quick withdrawal or rest after injury.
21
Q
walk through the pain pathway structures: (8)
A
stimulus injury =
A delta/C- fibers repond =
spinal cord =
brain stem =
mid-brain =
thalamus =
cerebral cortex =
pain perception
22
Q
What is visceral pain?
A
Pain from internal organs like the heart, GI tract, bladder, or uterus
23
Q
How does visceral pain feel?
A
Dull, crampy, pressure-like, and poorly localized.
24
Q
Why is visceral pain important?
A
Acts as a warning system for serious internal issues (e.g., appendicitis, MI).
25
What are characteristics of neuropathic pain?
Burning, shooting, tingling, electric shock-like; often chronic and maladaptive.
26
what is neuropathic pain?
increased sensitivity to painful stimuli = abnormal processing of pain info to PNS and CNS
27
What is phantom limb pain?
Pain felt in a limb that has been amputated.
28
phantom limb pain is ______ neuropathic pain
central
29
What is referred pain?
Pain perceived in an area different from the actual source (e.g., heart attack pain in arm).
30
Why does referred pain happen?
Visceral and somatic afferents converge on the same second-order neurons in the spinal cord.
31
What is acute pain?
Short-term pain that arises from tissue injury and resolves as healing occurs.
32
What fibers transmit acute pain?
A-delta fibers (sharp pain) and C fibers (dull pain).
33
What causes acute pain?
Tissue damage that activates nociceptors (e.g., surgery, injury, inflammation).
34
What’s the purpose of acute pain?
Protective—it promotes rest, withdrawal, and healing.
35
What are characteristics of acute pain?
Sudden onset, identifiable cause, well localized, resolves with healing
36
What is chronic pain?
Pain that lasts beyond normal healing time, typically over **3–6 months.**
37
timeline for chronic vs acute pain
acute up to 3 months
chronic over 3 months
38
What are characteristics of chronic pain?
Persistent, less localized, emotionally distressing, may not respond well to treatment
39
What is peripheral neuropathic pain?
Pain caused by damage or dysfunction of peripheral nerves outside the brain and spinal cord
40
What are common causes of peripheral neuropathic pain? (5)
Diabetic neuropathy
shingles (postherpetic neuralgia)
nerve compression (e.g., sciatica)
trauma
infection
41
What is central neuropathic pain?
Pain caused by damage or dysfunction in the central nervous system (brain or spinal cord).
42
What are common causes of central neuropathic pain? (4)
Stroke
spinal cord injury
multiple sclerosis
thalamic lesions
43
What is a migraine?
A recurring, throbbing headache often accompanied by nausea, light/sound sensitivity, and sometimes an aura.
44
What is the etiology of migraines?
Complex interaction of genetic, neurological, and vascular factors; often triggered by stress, hormones, foods, sleep changes
45
What are typical manifestations of a migraine? (5)
Unilateral, pulsating headache
Nausea and vomiting
Photophobia (light sensitivity)
Phonophobia (sound sensitivity)
May include aura (visual/sensory disturbances before onset)
46
How long does a migraine typically last?
4 to 72 hours if untreated.
47
What is a cluster headache?
A severe, unilateral headache that occurs in cyclical patterns or "clusters."
48
What is the etiology of cluster headaches?
Thought to involve hypothalamic activation and trigeminal autonomic pathways; exact cause unknown
49
What are typical manifestations of a cluster headache? (5)
Sudden, excruciating **pain around one eye**
Tearing, nasal congestion, runny nose (on same side)
**Ptosis** (drooping eyelid)
**miosis** (pupil constriction)
Restlessness or agitation during attack
50
How long does a cluster headache last?
15 minutes to 3 hours, up to 8 times a day during a cluster period.
51
What is a tension headache?
A common type of headache characterized by mild to moderate bilateral pain described as a **tight band around the head.**
52
What is the etiology of tension headaches?
Often triggered by stress, muscle tension, anxiety, or poor posture.
53
What are typical manifestations of a tension headache? (5)
Dull, aching, non-pulsating pain
**Bilateral** pressure or tightness
No nausea or vomiting
May have photophobia or phonophobia (but not both)
No aura
54
How long do tension headaches last?
30 minutes to several days.
55
What is a chronic daily headache?
Headache occurring 15 or more days per month for over 3 months.
56
What are typical manifestations of CDH? (4)
Varies depending on underlying type (migraine vs tension)
Persistent daily or near-daily headache
May include light/sound sensitivity, nausea, or muscle tenderness
Reduced responsiveness to typical headache treatments over time
57
What is a TMJ headache?
Headache caused by dysfunction or inflammation of the temporomandibular joint and surrounding muscle
58
What is the etiology of TMJ headaches? (5)
Jaw clenching
teeth grinding (bruxism)
joint degeneration
arthritis
trauma.
59
What are typical manifestations of TMJ headaches? (5)
Pain near the jaw, temples, or ear
Clicking or popping sounds when moving the jaw
Jaw stiffness or limited movement
Headache that worsens with chewing or talking
May radiate to the neck or shoulders
60
TMJ headahce is an example of __________ pain
referred
61
What is conjunctivitis?
Inflammation of the conjunctiva, the membrane covering the white of the eye and inner eyelids.
62
What are common causes (etiology) of conjunctivitis?
**Viral:** Often caused by adenovirus; highly contagious.
**Bacterial: **Caused by Staph, Strep, or Haemophilus species.
**Allergic: **Triggered by pollen, pet dander, dust.
**Irritant:** From chemicals, smoke, or foreign bodies.
63
What are common symptoms (manifestations) of conjunctivitis?
Red or bloodshot eyes
Itching or burning (esp. in allergic type)
Watery discharge (viral/allergic)
Thick, purulent discharge (bacterial)
Crusting of eyelids
Foreign body sensation
Photophobia (in more severe cases)
64
What are cataracts?
**Clouding** of the eye’s natural lens, leading to blurry vision.
65
patho of conjuncitivits
66
patho of cataracts
67
What are common causes (etiology) and risk factors for cataracts? (8)
Aging (most common)
Genetics
Trauma
Diabetes
Long-term corticosteroid use
Excessive UV light exposure
Smoking & alcohol
Congenital (from infections like rubella)
68
What are typical symptoms (manifestations) of cataracts? (7)
Blurry or cloudy vision
Halos around lights, especially at night
Glare sensitivity
Faded or yellowed colors
Frequent changes in glasses prescription
Difficulty with night vision
Double vision in one eye (sometimes)
69
What is glaucoma?
A group of eye disorders involving **increased intraocular pressure (IOP),** which can damage the optic nerve and lead to vision loss.
70
What are symptoms of open-angle glaucoma?
Gradual **peripheral** vision loss (painless)
Often asymptomatic in early stages
71
What is open-angle glaucoma?
A chronic condition where the drainage angle between the iris and cornea is open, but trabecular meshwork is blocked.
72
What is closed-angle glaucoma?
Sudden blockage of** aqueous **humor drainage, causing a rapid rise in IOP.
73
What are symptoms of closed-angle glaucoma? (6)
Sudden severe eye pain
Red eye
Blurred vision, halos around lights
Nausea and vomiting
Photophobia
Corneal edema (cloudy cornea)
74
What is retinal detachment?
Separation of the retina from the underlying pigment epithelium, disrupting its blood supply.
75
What are symptoms of retinal detachment? (5)
Sudden onset of floaters
Flashes of light ("photopsia")
"Curtain" or shadow over part of the visual field
Sudden vision loss
Distorted or wavy central vision (if macula is involved)
76
What is retinopathy?
A disease of the retina involving damage to retinal blood vessels, often due to diabetes or hypertension.
77
What are common causes of retinopathy?
Diabetes (diabetic retinopathy)
Hypertension (hypertensive retinopathy)
Retinal vein occlusion
Prematurity (retinopathy of prematurity)
78
What are general symptoms of retinopathy?
Blurred or fluctuating vision
Dark spots or "floaters"
Vision loss (partial or sudden)
Impaired night vision
79
what is the patho of open angle glaucoma?
80
what is the patho of closed angle glaucoma?
81
what is the patho of retinal retinopathy?
82
what is the patho of diabetic retinopathy?
83
what is the patho of retinal detachment?
84
What is diabetic retinopathy?
A complication of diabetes that damages the small blood vessels in the retina due to prolonged hyperglycemia.
85
What are symptoms of diabetic retinopathy? (5)
Blurred or fluctuating vision
Dark or empty areas in vision
Floaters
Sudden vision loss (esp. in PDR)
Difficulty seeing at night
86
What is macular degeneration?
A progressive eye disease that affects the macula, the **central part of the retina **responsible for sharp, detailed vision.
87
What are the risk factors for macular degeneration? (6)
Age (most common after 60)
Family history (genetic predisposition)
Smoking
Poor diet (high fats, low antioxidants)
Prolonged UV light exposure
Chronic inflammation
88
What are the common symptoms of macular degeneration? (4)
Blurry or distorted central vision
Wavy lines (metamorphopsia)
Decreased color perception
Dark or empty spots in central vision
89
what are the symptoms of hypertensive retinopathy? ( )
90
What is otitis media?
An **infection or inflammation of the middle ear**, often resulting from an upper respiratory infection (URI) like a cold.
91
What are the common causes of otitis media?
**Bacterial:** Most commonly caused by Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis.
**Viral:** Respiratory syncytial virus (RSV), influenza, adenovirus.
**Eustachian tube dysfunction:** Often caused by swelling due to allergies or sinus infections.
92
What are the typical symptoms of otitis media? (5)
Ear pain, especially when lying down
Hearing loss (due to fluid accumulation)
Fever, irritability (in children)
Tugging or pulling at the ear (common in young children)
Drainage of pus if the tympanic membrane ruptures
93
What type of hearing loss is caused by otitis media?
**Conductive** hearing loss, due to fluid in the middle ear preventing proper sound conduction.
94
what is the patho of otitis media?
95
What is conductive hearing loss?
Hearing loss due to **obstruction or damage** to the** outer or middle ear **that prevents sound from reaching the inner ear.
96
What are common causes of conductive hearing loss? (6)
Blockages in the ear canal (e.g., earwax impaction, foreign objects)
Otitis media (fluid in the middle ear)
Perforation of the tympanic membrane (eardrum)
Otosclerosis (abnormal bone growth in the middle ear)
Eustachian tube dysfunction
Trauma to the ear or head
97
What are symptoms of conductive hearing loss? (5)
Muffled hearing
Difficulty understanding speech, especially in noisy environments
Fullness or pressure in the ear
Tinnitus (ringing in the ear)
Pain or discomfort (if caused by an infection)
98
What is sensorineural hearing loss?
Hearing loss due to **damage to the inner ear** (cochlea) or the **auditory nerve** pathways.
99
What are common causes of sensorineural hearing loss? (8)
Aging (Presbycusis)
Noise exposure (long-term exposure to loud sounds)
Head trauma
Genetic factors (inherited conditions like Usher syndrome)
Infections (e.g., viral infections like mumps, measles, or meningitis)
Ototoxic medications (e.g., aminoglycosides, chemotherapy drugs)
Tumors (e.g., acoustic neuroma)
Autoimmune diseases (e.g., systemic lupus erythematosus)
100
what is the patho of sensorineural hearing loss?
101
What are the symptoms of sensorineural hearing loss? (5)
**Gradual** hearing loss, especially in high frequencies
Difficulty understanding speech (even when speech is loud enough)
Tinnitus (ringing or buzzing sounds)
Reduced clarity of sound, with sounds feeling "hollow"
Balance problems (less common)
102
what is the patho of conductive hearing loss?
103
what is the patho of vertigo?
104
what is the patho of motion sickness?
105
what is the patho of meniere's disease?
106
What is vertigo?
Vertigo is a sensation of spinning or dizziness, often caused by dysfunction within the vestibular system, which includes the inner ear or brain.
107
What are the common peripheral causes of vertigo?
Peripheral Causes: Dysfunction in the inner ear structures (e.g., Benign Paroxysmal Positional Vertigo (BPPV), vestibular neuritis, labyrinthitis).
108
What are the common central causes of vertigo?
Central Causes: Disturbances in the brainstem or cerebellum, such as stroke, tumors, or multiple sclerosis.
109
What are the symptoms of vertigo? (5)
Dizziness or spinning sensation
Nausea and vomiting
Nystagmus (involuntary eye movement)
Loss of balance and difficulty walking
Hearing loss (in cases of labyrinthitis)
110
What is Benign Paroxysmal Positional Vertigo (BPPV)?
A condition where displaced otoconia (calcium crystals) within the semicircular canals cause vertigo triggered by specific head movements.
111
What is motion sickness?
A condition caused by a sensory conflict between visual, vestibular (inner ear), and proprioceptive inputs, leading to symptoms like nausea.
112
What causes motion sickness?
When the brain receives **conflicting signals** about motion, for example, the inner ear senses movement (in a car or boat), but the eyes see a stable environment (e.g., fixed objects).
113
What are the common symptoms of motion sickness? (10)
Nausea and vomiting
Dizziness and vertigo
Pallor (pale skin)
sweating
increased salivation
Fatigue
headache
general discomfort
114
what is the patho of meniere disease?
115
What is Meniere's Disease?
A disorder of the inner ear characterized by recurrent episodes of vertigo, sensorineural hearing loss, and tinnitus due to fluid buildup in the inner ear.
116
What causes Meniere's Disease?
The exact cause is **unclear**, but it is believed to be related to endolymphatic hydrops (fluid buildup), possibly due to poor drainage, overproduction, or pressure imbalances in the inner ear.
117
What are the risk factors for Meniere's Disease? (8)
Age (typically affects people 40–60 years)
Family history (genetic predisposition)
Gender (more common in women)
Autoimmune diseases (e.g., rheumatoid arthritis)
Head injury (trauma to the inner ear)
Hypertension and cardiovascular disease
Stress (can trigger episodes)
Allergies, smoking, and alcohol use
118
What is the pathophysiology of Meniere's Disease? (3 parts)
**Fluid buildup **(endolymphatic hydrops) in the inner ear disrupts the vestibular and cochlear systems.
The buildup causes **distension in the inner ear** structures, affecting both balance (vestibular system) and hearing (cochlear system).
This leads to episodes of vertigo, fluctuating hearing loss, and tinnitus.
119
What are the hallmark symptoms of Meniere's Disease?
**Recurrent vertigo: **Episodes lasting from 20 minutes to several hours, often with sudden onset and no warning.
**Fluctuating sensorineural hearing loss:** Hearing loss typically worsens over time, starting with fluctuations in one ear.
**Tinnitus:** Ringing, buzzing, or fullness in the affected ear, especially during vertigo episodes.
**Aural fullness: **Sensation of fullness or pressure in the affected ear due to fluid buildup.
**Balance disturbances:** Persistent unsteadiness or difficulty walking, particularly between episodes.
