Lecture 5 PT 1 Flashcards by Alexander Lee

Where are 1st order neurons found?

Between sensory receptor and spinalcord/brainstem

How well did you know this?

Not at all

Perfectly

Where are 2nd order neurons found

Between Spinalcord and brainstem/thalamus

How well did you know this?

Not at all

Perfectly

Where are 3rd order neurons found?

Between thalamus to cerebral cortex

How well did you know this?

Not at all

Perfectly

Conduction vs translation

Conduction - impulse over pathway to CNS

Translation- CNS receives impulse and integrates info (may prepare response)

How well did you know this?

Not at all

Perfectly

Somatic/visceral/pain/tactile/proprioceptive senses are handled by what kind of receptors?

General receptors

How well did you know this?

Not at all

Perfectly

What kind of receptors handle Smell, Taste, vision, hearing/balance

specialized

How well did you know this?

Not at all

Perfectly

Hair cells are found on ________ receptors

specialized

How well did you know this?

Not at all

Perfectly

__________ determines the types of receptors that are activated

The stimulation (what kind it is)

How well did you know this?

Not at all

Perfectly

Exteroceptor vs Interoceptor

Exteroceptor- Detect external stimuli

Interoceptor- Stimuli coming from inside body

How well did you know this?

Not at all

Perfectly

Each type of receptor has a subset of _______ that are sensitive to simuli that either damage or have potential to damage

Nocioceptors

How well did you know this?

Not at all

Perfectly

Where are proprioceptors found?

Found in muscles, tendons, ligaments

How well did you know this?

Not at all

Perfectly

What receptor is described as:

Responds continiously as long as stimulus present

slow adapting

Detects pressure and form of objects

Tonic receptor

How well did you know this?

Not at all

Perfectly

What receptor is described as:

Adapts to continuous stimulus and stops responding to stimulus

-Fast adapting

-detects motion, vibration, rate of change

Phasic receptor

How well did you know this?

Not at all

Perfectly

What is larger, a 1a axon or a IV axon?

1a axon is larger than a IV axon

How well did you know this?

Not at all

Perfectly

sensory receptors with a smaller field are _______ sensitive than one with a larger field

more sensitive (can tell the difference between 1 and 2 points of contact that are close together)

How well did you know this?

Not at all

Perfectly

Larger receptive field are generally found _____

More proximally

How well did you know this?

Not at all

Perfectly

Smaller receptive fields are usually found…

distally

How well did you know this?

Not at all

Perfectly

Greater density of receptors is found ______ in the body

Distally

How well did you know this?

Not at all

Perfectly

What kind of cutaneous receptors are small field receptors?

Meisners corpuscles (light touch)
Merkel’s disks (pressure

How I will remember: M&Ms are small field receptors. Because both small field receptors start with an M

How well did you know this?

Not at all

Perfectly

What are the two kinds of subcutaneous receptors

Pacinian corpuscle - touch vibration

And Ruffini’s endings- stretch of the skin

How well did you know this?

Not at all

Perfectly

Superficial receptors typically have a _____ receptive field whereas subcutaneous fibers have a _____ receptive field

Superficial: small

Subcutaneous: Large receptive field

How well did you know this?

Not at all

Perfectly

Mechanoreceptors/Aβ fibers handle what sensations?

Light touch- vibration, stretch, skin pressure

How well did you know this?

Not at all

Perfectly

Free nerve endings AKA Aδ Fibers handle what sensations?

Course touch (pleasant touch/pressure/tickle/itch)
Pain
And Temperature (thermoreceptors)

The symbol is a delta symbol, how i will remember this: riding on delta airlines is very painful, hot, and the seats are course (maybe she meant coarse? Idk the slide said course) to the touch

True or false: naturally stimuli will only activate one type of receptor

False

What are the 4 attributes of conduction?

Modality Location Intensity Duration

A stimulus with a larger duration or larger amplitude will lead to…

More neurotransmitter release

Signal processing for integration occurs at what 3 levels of the somatosensory system?

Receptor Level Circuit Level Perceptual level

The speed of information processing is determined by what 3 factors

Axon diameter Myelination Number of synapses in pathway

Divergence vs Convergence

Divergence- Synapse spreads action potential to several areas of CNS Convergence - Synapses focus action potentials from several sensory neurons into narrow area of CNS

How are peripheral and Spinal dermatomes different in the extremities vs the trunk

The lumbosacral plexus and brachial plexus allow for mixing of spinal roots to where periphrial nerves receive multiple spinal levels, this mixing is not present in the trunk

What are 3 challenges to testing for sensory deficits

Patient alertness/cognition Cheating Equipment availability

Nerve conduction velocity testing

Compare electrical stimulation to peripheral nerve and compare with norms Distance latency - Time from stim to distal recording site Amplitude- # axons conducting Conduction velocity- testing for Myelination

True or false: a nerve conduction velocity test is typically done at the same time as EMG

True

What is a SSEP (somatosensory evoked potentials) test

Tests peripheral and central pathways, the conduction is measured proximally and at the cerebral cortex

What is the order of sensory loss (note: sensory returns in reverse order)

1. Conscious proprioception/ light touch 2. Cold 3. Fast/sharp stinging pain 4. Heat 5. Slow aching pain

Nerve compression impacts large myelinated axons first and _______ last

Smaller nocioceptive thermal and autonomic axons last

What is sensory Ataxia?

**Loss of somatosensory** , can be caused by Injury to peripheral nerves, dorsal roots, dorsal columns of SC, or medial lemnisci

What is the difference between peripheral ataxia and cerebellar ataxia?

Difference in eye open/eye closed testing. Patients w/ cerebellar ataxia will preform the same with eyes open and closed Proprioception is intact with cerebellar ataxia and absent with sensory ataxia

What is Shingles/Herpes zoster and how is it treated

Varicella Zoster virus infects dorsal root ganglion and appears as painful rash along dermatome Treatment: antiviral within 72 hours Prevention: vaccine for people over 50

Nocioceptive pain vs non-nocioceptive pain

Nocioceptive: Acute/chronic tissue injury Non-nocioceptive: malfunction of neural pain regulating process WITHOUT presence of tissue injury

What kind of pain describes neuropathic, central sensitivity syndromes, or pain syndromes

Non-nocioceptive pain

Nocioceptors are free nerve endings that carry fast and slow pain by __________ (small fibers) to spinal cord

Aδ or C fibers (small fibers)

Pain experience is strongly linked to _______, ______, and cognitive phenomena

Emotional, behavioral

What areas of the brain are activated during central processing of pain?

Cingulate and insular areas

What are the two kinds of inhibitory neurons in the spinal cord for pain?

Enkephalin and Dynorphin

Where are the 3 areas where the brain has opiate receptors to bind with endorphins

Rostral ventromedial medulla (raphespinal tract) Periaqueductal gray in midbrain Locus Coeruleus in pons (Ceruleospinal tract)

What are the 3 kinds of endorphins for inhibits pain signals?

Enkephalins , dynorphins, and B- endorphins

What is gate control theory?

Activation of **non-nocioceptive sensory neurons can close “gate**” for central transmitting of nocioceptive signal (pain) Note: demonstrates that pain perception is regulated by balance of activity in nocioceptive and non-nocioceptive afferent fibers

How does the periphery of the nervous system inhibit pain?

Decrease synthesis of prostaglandins

How does the dorsal horn help with inhibiting pain?

Release enkephalin and dynorphin. (endogenous opioids)

Nocioceptors that are excessively reactive to stimuli demonstrate ________ __________

Peripheral sensitization Sensitized neurons can fire in response to normal stimuli and make it feel painful

______ pain usually occurs after a tissue has been damaged

Deep pain

True or false: Musculoskeletal injuries can trigger both fast and slow pain

True

What is the explanation for referred pain?

pain that is perceived as coming from site distincly different from actual origin site

Fibromyalgia, complex regional pain syndrome, chronic nonspecific LBP, and Migraines are example of….

Chronic pain as a disease/ **primary pain** No evidence of actual tissue damage