3.3 Pain and Sensory exam
What kind of a response does the indirect ALS pathway that goes to the reticular system elicit?
Alerts pt to injury Pt evades injury
What are the steps in the pain path that is opposite of fear avoidance, beginning w/ injury?
Injury—> Pain experience—> No fear—> Confrontation—> Recovery
Which free nerve ending fiber makes up the direct pathway?
A delta
Which free nerve ending fibers, that detect pain, are faster?
A delta because of myelin
What are the two types of free nerve endings that detect pain?
A delta fibers C fibers
What pathway detects pain?
ALS
What does the hypothalamus do for the indirect ALS pathway?
ANS response—> Increase HR Release cortisol
Between A delta and C fibers, which envokes a more conscious response?
C fibers
Which free nerve ending fiber makes up the indirect pathway?
C fibers
Does the direct pathway or indirect pathway inhibit pain? What allows for inhibition?
Indirect Release of NT
People will take part in ___________ because they fear pain and want to avoid it
Fear avoidance
What structure are pain receptors?
Free nerve endings
What are the steps in the cycle of fear avoidance beginning w/ injury
Injury—> Pain experience—> Pain catastrophizing (ex. Fear of blood)—> Pain related fear—> Avoidance hypervigilance—> Disuse, depression, disability
Besides free nerve endings, what other structures do A beta fibers carry sensory signals from?
Merkel's discs Meissner's corpuscles Pacinian corpuscles
Besides the reticular system, what 'other brain structures' does the indirect ALS pathway go to?
Mesencephalon Superior colliculus Hypothalamus
What does the mesencephalon do for the indirect ALS pathway?
Modulates pain reception Plays a role in inhibiting pain Transmits to amygdala (for emotion)
What NT inhibit pain in the indirect pathway?
NE Dopamine Serotonin
Where does the indirect ALS pathway go?
Other brain structures
What is an observable aspect of pain neurophysiology?
Pain behavior
What 'other brain structures' does the indirect ALS pathway MOSTLY go to?
Reticular system then thalamus
What is the pattern theory?
See different patterns when there are 2 stimuli at the same time (ex. Pinprick plus tickle)
What are the 3 different theories to pain modulation?
Specificity Pattern Gate control
What are nonobservable, individualized aspects of pain neurophysiology?
Suffering Pain Nociception
Where does the direct ALS pathway go?
Thalamus
What does the superior colliculus do for the indirect ALS pathway?
Turn head/ eyes toward pain
What is the specificity theory?
special pain receptors detect pain (nociceptors)
What is the gate control theory?
the theory that the spinal cord contains a neurological "gate" that blocks pain signals or allows them to pass on to the brain. The "gate" is opened by the activity of pain signals traveling up small nerve fibers (A delta and C fibers) and is closed by activity in larger fibers (A beta) or by information coming from the brain.
