Somatosensory system & Special Senses

Question 1

Cell bodies location

Answer 1

Cell bodies are located in two regions:

• adjacent to the spinal cord dorsal root ganglia, DRG
• base of skull -trigeminal, TG (CNV)

Question 2

Wilder Penfield

Answer 2

Cortical Homunculus

Question 3

Mechanorepectors Channel type

Answer 3

Involves Transient Receptor Potential (TRP) channels

Question 4

Proprioceptors axon types

Answer 4

A alpha fibers (myelianted)

Question 5

Hapsis axon type

Answer 5

A beta fibers (myelianted)

Question 6

itch/tickle axon type

Answer 6

C fibers (unmyelianted)

Question 7

thermoreceptors axon type

Answer 7

C fibers (unmyelinated) & A delta fibers (myelinated)

Question 8

nociceptors axon type

Answer 8

Fast- A delta (myelinated)

Slow - C fibers (unmyelinated)

Question 9

Referred Pain (Dermatomes)

Answer 9

Heart localized to the neck, left shoulder & arm

Stomach localized above umbilicus

Colon localized below umbilicus

ex: shingles -> tiny bumps form on skin when nerves are damaged

Question 10

Cranial Headache (Meningitis)

Answer 10

inflammation of meninges

Question 11

Cranial Headache (migraine)

Answer 11

vasospasm then vasodilation

Question 12

Cranial Headache (hangover)

Answer 12

irritation of meninges by alcohol biproducts

Question 13

Extracranial Headache (Tension)

Answer 13

emotional tension of muscles of neck/scalp

Question 14

Extracranial Headache (Sinus Headache)

Answer 14

irritation of nasal structures

Question 15

Extracranial Headache (eye strain)

Answer 15

excessive contraction of ciliary muscles (for focusing) or of facial muscles

Question 16

Somesthesia

Answer 16

“Somesthesia is the perception of bodily sensations that include the skin, muscles, joints, and tendons. Such sensations would encompass the perception of pain, temperature, light touch, deep touch, vibration, proprioception (recognition of the relative position of a body part), and kinesthesia (awareness of movement of a limb or joint

Question 17

Sensory systems, unlike somatosensory systems do not involve

Answer 17

• dorsal root ganglions or trigeminal ganglions instead they are located in the cranial sensory ganglia
• somatosensory conveys information in series but sensory conveys in a nerve bundle

Question 18

Dysgeusia

Answer 18

reduced sense of taste

causes: : Diabetes Mellitus, hypothyroidism, some meds, throat or tongue infections, chronic smoking, viral load

Question 19

ageusia

Answer 19

complete loss of taste

Question 20

Hyposmia

Answer 20

reduced sense of smell

Underlying causes: head trauma, Parkinson’s, Alzheimer’s, some meds, chronic smoking, viral load

Question 21

Anosmia

Answer 21

temporary loss of smell

Question 22

Deuteranomaly

Answer 22

(green shifted towards red)

Question 23

Deuteranopia

Answer 23

(absence of green cones)

Question 24

Protanomaly

Answer 24

(red shifted towards green)

Question 25

Protananopia

Answer 25

(absence of red cones)

Question 26

tritanomaly

Answer 26

reduced sensitivity to blue light

Question 27

tritanopia

Answer 27

absence of blue cones

Question 28

illusion

Answer 28

- An illusion occurs when physical stimulus and visual perception do not correspond - Complex perceptual phenomena - Link between sensory stimulus and cognitive processing poorly understood - How the brain perceives the same visual image in different ways is also not known

Question 29

Synesthesia

Answer 29

Stimulation of one sensory pathway results in automatic stimulation of different sensory pathway

Question 30

Auditory Cortex and Association Areas

Answer 30

- Arranged by tonotopic maps - High frequency sounds at one end of map; low frequency sounds at other end of the map - Discrimination of sound patterns is lost when auditory cortex destroyed

Question 31

cataracts

Answer 31

- Impairments in Vision | - Clouding of lens

Question 32

glaucoma

Answer 32

Damage to optic nerve | Impairments in Vision

Question 33

age-related macula degeneration

Answer 33

Damage to retina | Impairments in Vision

Question 34

scotoma or blind spot

Answer 34

lesion of retina | Impairments in Vision

Question 35

Diabetic retinopathy

Answer 35

damage to retinal vessels | impairment in vision

Question 36

Myopia/Hyperopia

Answer 36

Changing shape of eye (decreased visual acuity) | impairment in vision

Question 37

Nerve deafness

Answer 37

impairment of the cochlea or the auditory nerve

Question 38

Conduction deafness

Answer 38

impairment of tympanic membrane or ossicles

Question 39

-Congenital deafness

Answer 39

occurs from birth whereas adventitious deafness occurs after birth (usually noise related)