Nervous System 7

Question 1

________ are on free nerve endings & commonly found in the skin. Also in hypothalamus, spinal cord, & deep tissues.

Answer 1

Thermal Receptors (thermoreceptors)

Question 2

There are _____ times as many cool receptors at any skin

Answer 2

3-10

Question 3

____ signals are transmitted by C and A delta fibers

Answer 3

Warm signals

Question 4

____ signals are transmitted by A delta and C fibers

Answer 4

Cool signals

Question 5

Which signals use more A delta fibers?

Answer 5

Cold signals

Question 6

_______ channels have been identified, each sensitive to a different temperature range. Some chemicals (Capsaicin, Menthol) elicit thermal sensations, too.

Answer 6

Transient Receptor Potential (TRP)

Question 7

Temperature increases the rate of intracellular chemical reactions > 2 times per ____ degrees Celsius change

Answer 7

10 degrees

Question 8

Tickling, Pricking, Aching, Burning, Numbing are considered ____ pain

Answer 8

COLD PAIN:

Question 9

Sharp, Pricking, Stinging, Burning, Throbbing are considered ____ pain

Answer 9

HOT PAIN:

Question 10

IS the adaptation of thermoreceptors phasic or tonic?

Answer 10

Phasic

Question 11

T/F: If the temp reaches one of the pain thresholds, the sensation becomes. more persistent throughout the stimulus

Answer 11

True

Question 12

Warm and Cool receptors are best able to detect a change at the _____ range of their temperature sensitivity (that is where they are most sensitive)

Answer 12

mid-range

Question 13

T/F: If nociceptors are simultaneously activated, the system is even better able to discern small changes in temperature

Answer 13

True

Question 14

As temperature increases (or decreases) within a range of a thermoreceptor’s sensitivity, _____ (more or less) receptors are activated, based on their varying thresholds

Answer 14

more and more

Question 15

The greater the area of skin affected by a thermal stimulus, the ______ the number of receptors, receptive fields, and first order neurons activated and thus the _____ the perceived sensation.

Answer 15

greater

Question 16

There is a much _____ ability for detection of a temperature stimulus if a large region is activated.

Answer 16

greater

Question 17

Receptors in the oral cavity are primarily sensitive to _____ but certain ones are sensitive to chemicals

Answer 17

Temp

Question 18

____ receptor subtype: 1.TRPV1 Receptor 2.Activated by capsaicin, temperature >43°C, and protons3.Decreases the threshold of channel activation so that heat is perceived at 33°C.

Answer 18

Vanilloid Receptor Subtype

Question 19

______ receptor subtype: 1.Menthol and related compounds2.Decreases the threshold of the channels so that warmer compounds are perceived as cold.

Answer 19

Cold-Menthol Receptor Type I (CMR1/TRPM8)

Question 20

Small receptive fields _____ acuity

Answer 20

increase

Question 21

Are there more cool or warm receptors in the oral cavity

Answer 21

Cool

Question 22

Which sensation is better at accurately detecting thermal increments?

Answer 22

Warm

Question 23

Thermoreceptors in ____ are the most sensitive to changes in temperature.

Answer 23

tongue

Question 24

Due to activation of nociceptors. This usually results in the perception of PAIN, an unpleasant & emotional experience associated with actual or potential tissue damage.

Answer 24

NOCICEPTION

Question 25

T/F: All nociception produces pain, though not all pain results from nociception.

Answer 25

True

Question 26

_____ whatever its cause, is never benign. ____ is the most common reason patients seek healthcare AND the most common symptom of disease.

Answer 26

PAIN

Question 27

T/F: Pain is polymodal and can be evoked by any stiumuli

Answer 27

True

Question 28

____ pain: Physiologic Pain; <6 months duration

Answer 28

ACUTE

Question 29

____ is a form of acute pain From skin, subcutanous tissues or mucus membranes (Superficial) or muscles, tendons, joints or bones (Deep).

Answer 29

Somatic:

Question 30

____ is a form of acute pain Due to a disease process or abnormal function involving an internal organ (Visceral) or its covering (Parietal).

Answer 30

Visceral:

Question 31

____ somatic pain is localized, sharp, pricking and burning

Answer 31

Superficial Somatic:

Question 32

_____ somatic pain is dull, aching, diffuse and can be referred

Answer 32

Deep Somatic:

Question 33

____ visceral pain is dull, diffuse, poorly localized and associated with nausea and autonomic symptoms.

Answer 33

True Visceral:

Question 34

____ visceral pain is sharp, stabbing and better localized than true pain.

Answer 34

Parietal Visceral

Question 35

_____ pain happens when two nociceptive afferent neurons—from different regions of the body—converge on the same second order neuron. The brain doesn’t know which is the true source of input and may make a mistake in interpretation.

Answer 35

Referred pain

Question 36

____ pain Pathologic Pain; occurs beyond the usual course of an acute disease or after a reasonable time for healing to occur

Answer 36

CHRONIC

Question 37

Due to activation of nociceptors

Answer 37

Nociceptive

Question 38

Due to neuronal injury•Pain is paroxysmal, sharp and stabbing•Pain is associated with Hyperalgesia

Answer 38

Neuropathic:

Question 39

(increased sensitivity to pain)

Answer 39

Hyperalgesia

Question 40

____ receptors are usually found on free nerve endings and are sensitive to mechanical, thermal, and chemical stimuli

Answer 40

Nociceptors

Question 41

Chemicals known to _____ nociceptors: Substance P, ATP, calcitonin gene related peptide (CGRP), glutamate, aspartate, Bradykinin, potassium, Histamine, serotonin

Answer 41

excite

Question 42

Chemicals known to _____ nociceptors: Substance P,Prostaglandins, Histamine, Bradykinin

Answer 42

sensitize

Question 43

Chemicals known to _____ nociceptors: Enkephalins, β Endorphin, Cannabinoids

Answer 43

inhibit

Question 44

Minimal adaptation and a nociceptors activity actually _____ if the painful stimuli continues (hyperalgesia) due to nociceptor sensitization.

Answer 44

INCREASES

Question 45

(painful sensation to a innocuous stimulus)

Answer 45

Allodyina

Question 46

Summation of nociception is _____ (based on # of receptors activated).

Answer 46

spatial

Question 47

Stimulation of nociceptors also leads to antidromal (reverse) activation of nociceptive nerve terminals and release of substance P and calcitonin gene related peptide. Release of these peptides causes mast cell degranulation, vasodilation and edema, and further sensitization and activation of nociceptors

Answer 47

Neurologic inflammation

Question 48

The _____ includes red flush (flare), local tissue edema, and sensitization to noxious stimuli

Answer 48

Triple response

Question 49

____ fibers transmit pain in CNS that is small and myelinated; neurotransmitter includes glutamate; sharp localized pain; thermal and mechanical stimuli

Answer 49

A-delta fibers

Question 50

____ fibers transmit pain in CNS are unmyelinated; neurotransmitter includes substance P; dull diffuse pain; thermal, chemical, and mechanical stimuli

Answer 50

C fibers

Question 51

Which major pathway is the main pain pathway?

Answer 51

Spinothalamic

Question 52

____ pathway is the spinothalamic division: Mostly A delta fibers. Provideslocation, intensity, & duration information.

Answer 52

Neospinothalmic:

Question 53

____ pathway is the spinothalamic division: Mostly C fibers. Some of these fibers synapse with brainstem structures (Reticular Formation, Periaqueductal Gray Region, Limbic System, Hypothalamus) and also with diffuse areas of the cortex for poorly localized sense of pain.

Answer 53

Paleospinothalamic:

Question 54

____ pathway is an alternate pathway: Mediates arousal & autonomic responses

Answer 54

Spinoreticular pathway.

Question 55

____ pathway is an alternate pathway: Activates anti-nociceptive, descending pathways

Answer 55

Spinomesencephalic pathway.

Question 56

____ pathway is an alternate pathway: Activates the hypothalamus

Answer 56

Spinohypothalamic pathway

Question 57

What are the 2 types of neurons that the second order neuron in the Neospinothalmic and Paleospinothalamic tracts can be?

Answer 57

Nociceptive neurons or wide-dynamic range (WDR) neurons

Question 58

_____ neurons receive noxious only noxious stimuli

Answer 58

Nociceptive-specific neurons

Question 59

_____ neurons also recieve non-noxious afferent input from A-beta, A-delta, and c fibers

Answer 59

wide-dynamic range (WDR) neurons

Question 60

_____ neurons are found in Lamina 5 and During repeated stimulation, These neurons characteristically increase their firing rate exponentially (wind-up), even with the same stimulus intensity. They have larger receptive fields than nociceptive-specific neurons; responsible for analgesia and allodynia

Answer 60

wide-dynamic range (WDR) neurons

Question 61

____ neurons cross over in spinal cord; Found in lamina I and have discrete, somatic receptive fields; they are normally silent and respond only to high-threshold noxious stimulation, poorly encoding stimulus intensity.

Answer 61

Nociceptive specific neuron

Question 62

____ neurons are found in the dorsal horn of the spinal cord. They respond to all somatosensory modalities. Normally only sensitive to non-noxious stimuli UNLESS the stimulus is highly noxious.

Answer 62

Wide-Dynamic Range (WDR) Neurons

Question 63

_____ of pain enhances pain signaling

Answer 63

Facilitation of pain

Question 64

Perception of a non-noxious stimulus as pain

Answer 64

Allodynia

Question 65

In the __________, The A-β fibers activate an inhibitory interneuron that causes post-synaptic inhibition of the Second-order neuron for the Pain Pathway. This inhibition leads to a weaker pain signal being sent to the thalamus and somatosensory cortex. (mechanoreceptors)

Answer 65

Gate Control Theory of Pain

Question 66

In ______, Stimulate pain in other regions of the body to inhibit pain; also called Diffuse Noxious Inhibitory Control (DNIC) or Conditioned Pain Modulation (CPM))

Answer 66

Pain inhibits pain

Question 67

In _____, A second noxious stimulus, leads to activation of the PAG, NRM and RVM in the brainstem, which results in diffuse analgesic effect over the rest of the body.

Answer 67

Conditioned Pain Modulation (CPM)

Question 68

What endogenous opiate in the body inhibits the first-order and second-order neurons (nociceptive specific and/or WDR neurons) in conditioned pain modulation

Answer 68

Enkephalin

Question 69

_____ is the selective suppression of pain without effects on consciousness or other sensations.

Answer 69

Analgesia

Question 70

What 3 parts of the brain are used in endogenous analgesia system?

Answer 70

PAG, NRM, and RVM

Question 71

What are the 2 tracts that conveys orofacial pain?

Answer 71

Trigeminospinothalamic and trigeminoreticular tract

Question 72

Dentin and enamel has limited space to swell in the ____ state, so results in exaggerated pain even with mild inflammation

Answer 72

inflammatory state

Question 73

Painfully noxious _____ stimulus do not cause pain in an uninflamed healthy tooth due to thermal insulating of the enamel. But, with missing enamel and exposed dentin, a slight thermal stimuli will cause sudden and stinging pain.–It is difficult to distinguish between between noxious hot or cold stimuli.

Answer 73

hot/cold stimuli

Question 74

Weak ______ to exposed dentin result in intense pain while in skin this would result in the sensation of light touch.

Answer 74

air puffs

Question 75

Stimulation of _______ by any kind of stimulus results in a painful sensation.

Answer 75

tooth pulp

Question 76

Why is there difficulty localizing tooth pain?

Answer 76

Large receptive fields

Question 77

What part of the tooth is highly innervated with sensory afferents mostly for pain?

Answer 77

Pulp

Question 78

dentin has limited innervation but is sensitive due to ______

Answer 78

dentinal tubules

Question 79

____ is a mineralized, avascular tissue; Suprasensitive to extreme temperatures, particularly at the neck of the tooth (gingival recession, wear of cementum and enamel), Sensitive to hyperosmotic solutions, and NOT sensitive to KCl, bradykinin, and histamine

Answer 79

Dentin

Question 80

Dentinal and pulp nociceptor information travels via ___ fibers and ____ fibers mainly

Answer 80

Aδ and C fibers

Question 81

The nerve fibers in tooth pulp are ~90% ____ fibers

Answer 81

C-fibers.

Question 82

Is dentinal pain sharp or dull pain?

Answer 82

Sharp

Question 83

Is pulpal pain sharp or dull pain?

Answer 83

Dull

Question 84

___ theory of dental nociception is explained by Free nerve endings in dentinal tubules are activated

Answer 84

Neural theory

Question 85

___ theory of dental nociception is explained by Odontoblasts are excited and transduce the signal to nearby nerve cells

Answer 85

Odontoblast Transducer theory

Question 86

___ theory of dental nociception is explained by Stimulus displaces fluid in dentinal tubules which activates mechanoreceptors in nerve endings of dentin or pulp.

Answer 86

Hydrodynamic theory

Question 87

T/F: Not all dental pains are due to noxious temperatures (ex. water spray, puff of air, sweet substances, etc.)

Answer 87

true

Question 88

What portion of the PDL is the most heavily innervated?

Answer 88

Apical portion

Question 89

What fibers are used in periodontal nociception information from free nerve endings to travel?

Answer 89

A delta/C fibers

Question 90

The _______ regulate the forces applied by the teeth in occlusion, mastication and biting. These receptors are slowly adapting, show directional sensitivity and their response varies with the force applied to the tooth.

Answer 90

periodontal mechanoreceptors (Ruffini endings)