Sensory System

Question 1

Normal Pressure Hydrocephalus

Answer 1

• headache
• ataxic gait= difficulty waling/magnetic gain (wobbly)
• dementia=confused thinking/slowness of thought (weird)
• incontinence= loss of bladder control (wet)

Question 2

Neuromuscular Spindle

• mm stretch and position sense (___)
• -found in ___ ___ mm
• -_-__=very fast conducting

Answer 2

proprioception
all striated mm
a-alpha

Question 3

Meissner Corpuscle

• ____ touch (2pt)
• -concentrated in ____ ____
• -__-___ fiber= fast conducting
  (ex. hand in pocket for quarter not dime)

Answer 3

discriminative
finger tips
a-beta

Question 4

Pacinian Corpuscle

• detection of _______
• -concentrated in ____ and in _____
• -_-____ fiber= fast conducting

Answer 4

vibration
fingers and palm
a-beta

Question 5

Merkel Nerve Ending

• ______ touch (2pt)
• -_____ touch detail (edges of object, texture)
• -_-___ fiber= fast conducting

Answer 5

discriminative
fine touch
a-beta

Question 6

Free Nerve Ending

• sensation of:
• -__
• -__
• -__

Answer 6

pain (glutamate/substance P)
crude touch (cotton ball/feather)
temperature

Question 7

Local Anesthetic

• must pass through ___,___,___
• block ___ ____ (changes ion balance)
• must block ___ nodes

Answer 7

epineurium, perineurium, endoneurium
sodium influx
3

Question 8

Local Anesthetic
-binds to receptor site on ion channel on ______ side
-binds more readily to ____ _____
(works faster if neuron is firing off)

Answer 8

intracellular side

active neurons

Question 9

Nociception vs Pain

Answer 9

–

Question 10

Types of Pain

Answer 10

• fast pain= irritation from brain

- slow pain= seconds wave (throbbing/continuous)

Question 11

Hyperalgesia

Answer 11

-lowered threshold of affected tissue to pain (abnormal sensitivity)

Question 12

Allodynia

Answer 12

-pain produced by normal innocuous (nonirritating) stimulus

Question 13

Posterior Horn:
Rexed's laminae-
-I
-II (\_\_\_\_\_ \_\_\_\_\_\_)
-V

Answer 13

substantia gelatinosa

Question 14

Discriminative Touch:
posterior column- \_\_\_ \_\_\_ pathway
-2 pt discrimination
-\_\_\_\_ proprioception
-\_\_\_\_\_ sense
--a- \_\_\_ fiber
--collateral to lamina II
-decussates in \_\_\_\_\_\_
-relays in \_\_\_\_\_\_ thalamus
--ventral posteriolateral nucleus (VPL)
-terminates in \_\_\_\_\_\_\_ gyrus

Answer 14

medial lemniscal pathway
conscious proprioception
vibratory sense
a-beta fiber
decussates in medulla
relays in the lateral thalamus
terminates in the postcentral gyrus

Question 15

Somatotopical

Answer 15

-point-for-point correspondence of an area of the body to a specific point on the central nervous system (brain)

Question 16

Somatic Sensory cortex on the brain-

Answer 16

postcentral gyrus

Question 17

Fast Pain:
pain
temperature
crude touch
-a-\_\_\_\_\_ fiber
-terminates on lamina \_\_
-decussates in spinal cord
-\_\_\_\_\_\_\_\_ pathway
--relays in lateral thalamus
--ventral posterolateral nucleus (VPL)
-terminates in \_\_\_\_\_\_ gyrus

Answer 17

a-delta fiber
lamina I
spinothalamic pathway
terminates in postcentral gyrus

Question 18

Slow Pain:
pain
temperature
crude touch
-\_\_\_\_ fiber
-lamina \_\_\_
-excitatory interneauron (in L\_\_)
-lamina \_\_
-decussates in spinal cord
-\_\_\_\_\_\_\_\_ pathway
--brainstem reticular pathway
-relays in medial thalamus
--intralaminar nuclei
-many regions of cortex to access where pain is coming from

Answer 18

c fiber
lamina II
Lamina V
spinoreticular pathway

Question 19

Referred Pain:

• _______ signals from internal structures perceived as pain from surface structures
• -mixing of signals at the level of the :
• –______
• –______
• -no _______ maps of viscera
• • represents embryonic origin (diaphragm/heart)
• pattern generators
• grasp reflex
• flexion reflex (uses pain sensors at point of origin, cannot override)

Answer 19

nociceptive signals
signals at the level of spinal cord and brainstem
no somatotopic maps

Question 20

Itch:
a small subset of _____ ______
-produce and release _______
–results in intense scratching

Answer 20

somatosensory neurons
Nppb (natriutetic polypeptide b)
-axon terminals in lamina I of dorsal horn

Question 21

Cortical Plasticity

Answer 21

-refers to changes in neural pathways and synapses which are due to changes in behavior, environment and neural processes, as well as changes resulting from bodily injury

Question 22

Pain Regulation (suppressing/activating)
-\_\_\_\_\_ \_\_\_\_\_\_ \_\_\_\_\_
limbic system:
-periaqueductal gray
- \_\_\_ \_\_\_ \_\_\_ (medulla)
-raphe spinal tract (\_\_\_\_\_\_\_)
-lamina \_\_

Answer 22

dorsal column collateral

• nuclear raphe magnus
• serotonin (NT- blocks pain)
• lamina II (inhibitory- blocks pain)

Question 23

The Pain Matrix:
areas most commonly activated by pain
-
-
-
-
-
other regions activated:
-basal ganglia
-cerebellum (motor)
-amygdala (fear/anxiety)
-hippocampus (reward)

Answer 23

primary somatosensory cortex; S1
secondary somatosensory cortex; S2
insula
anterior cingulate cortex
dorsolateral prefrontal cortex

Question 24

Axon Reflex:
Triple Response
-
-
-

Answer 24

scratch
1 red line
2 flare
3 wheal (swelling)

Question 25

Generic Somatic Afferent Pathway:
GSA
-3 neurons
--1 cell body of origin=\_\_\_ \_\_\_\_ \_\_\_
--2 cbo= is \_\_\_\_\_\_\_; axon decussates
--3 cbo= \_\_\_\_\_\_ thalamus; to somatic sensory cortex

Answer 25

dorsal (posterior) root ganglion or cranial nerve ganglion
ipsilateral- posterior horn–>medulla (decussation)
lateral

Question 26

Dermatomes

Answer 26

-the area of skin supplied with afferent nerve fibers by a single posterior spinal root
==overlapping bands of anesthesia (T8 needs T7 to T9)

Question 27

Sensory Pathway Termination

Answer 27

brainstem retiuclar formation–>periaqueductal gray

cortex