Week 4: Sensory Systems (limited pathway information) Flashcards
What is somatosensory?
Bodily sensations of touch, pain, temperature, vibration, and proprioception.
somatosensory information is received from sensory receptors in:
skin joints ligaments muscle fascia
Free nerve endings are responsible for:
Do they have large receptor fields, small receptor fields or both?
temperature
pain
crude touch
They have large or small receptor fields.
Merkel cells are responsible for:
Do they have large receptor fields, small receptor fields or both?
shape and texture of light touch
small receptor fields
Meissner corpuscles are responsible for:
Do they have large receptor fields, small receptor fields or both?
motion detection and grip control of light touch
small receptor fields
Ruffini endings are responsible for:
Do they have large receptor fields, small receptor fields or both?
- stretching of the skin (which supplies secondary info regarding proprioception)
- vibration and pressure
Large receptor fields
Pacinian corpuscles are responsible for:
Do they have large receptor fields, small receptor fields or both?
vibration and pressure
large receptor fields
What is proprioception?
the sense of a joint/ limb position in space
What 3 things contribute to proprioception?
- muscle spindles
- Golgi tendon organs
- joint receptors
Muscle spindles can trigger what 2 responses?
muscle contraction and antagonist inhibition.
What fibers included in muscle spindles are responsible for stretching the muscle rather than contracting?
intrafusal fibers
Muscle spindle can be categorized by how ______ or how _______ they are stretched.
fast; far
synonymous with RATE and DEGREE
Muscle spindles are crucial to:
the myotatic (stretch) reflex
Golgi tendons are located:
near the muscle tendon junction
Golgi tendon organs monitors ________ within the tendons
tension
Golgi tendon organs can trigger 2 responses:
muscle relaxation (autogenic inhibition)
and
inhibit muscle spindles
What is the exception to the general responsibilities of golgi tendon organ?
can trigger contraction right before a muscle is passively stretched. This is crucial for proprioceptive neurotransmitter rehabilitation.
Joint receptors monitor:
stretch in synovial joints
Joint receptors send information to:
cerebellum and spinal reflex arcs
What are the other important receptors in joints and what are their functions?
Pacinian: AROM and compression
Ruffini: indicate end range and passive range of motion
Free nerve endings: pain from joint inflammation; non - noxious stress (pressure, temperature, vibration, etc.)
What is the general pathway from the somatosensory neuron in the PNS?
- Distal axons (PNS): Mechanoreceptors & proprioceptors
- Dorsal and ventral rami: (dorsal does back, ventral does trunk and limbs)
- spinal nerve
soma in dorsal root ganglion - Proximal axon (CNS) Dorsal root
What are dermatomes?
area of skin with sensory innervation by a single dorsal spinal root
Cutaneous peripheral nerve supply an area of skin that is related to a:
peripheral nerve
The anterolateral column is responsible for:
pain, temperature, pressure and crude touch
The dorsal column is responsible for:
light touch, proprioception and vibration
The medial leminiscal pathway conveys:
proprioception, vibration, and discriminative touch.
The anterolateral system conveys
pain, temperature, crude touch, pressure
The anterolateral system contains what 3 tracts:
spinothalamic tract
spinoreticular tract
spinomesencephalic tract
Discrimination (location, intensity) of pain, temperature, and crude touch are aspects of what tract in the anterolateral system?
spinothalamic tract
Emotional and arousal aspects of pain are aspects of which tract in the anterolateral system?
- spinoreticular tract
pain modulation is a part of what tract in the anterolateral system?
spinomesencephalic tract
What structure is a crucial relay structure for all afferent pathways traveling to the cortex?
The thalamus
What makes up the relay nuclei of the thalamus?
medial nuclear group
lateral nucleus group
anterior nuclear group
What makes up the internal medullary lamina?
intralaminar nuclei
multiple cortical projections`
The internal medullary lamina receives input from:
The RAS in the reticular formation.
The thalamic reticular nucleus contains ____________ integration and it projects to the:
thalamic; cortex
What are the 6 lateral nuclear groups in the thalamic nuclei?
- ventral posterior lateral nucleus (VPL)
- ventral posteromedial nucleus (VPM)
- ventral lateral nucleus (VL)
- ventral anterior nucleus (VA)
- Lateral geniculate nucleus (LGN)
- Medial geniculate nucleus (MGN)
Ventral posterior lateral nucleus is involved in sending information from:
somatosensory of spinal chord to primary sensory cortex
Ventral posteromedial nucleus is involved in sending information from:
Somatosensory (CNS) to primary sensory cortex
Ventral lateral nucleus is involved in sending information from:
cerebellum and basal ganglia to primary motor cortex and association motor cortices
Ventral anterior nucleus is involved in sending information from:
cerebellum and basal ganglia to the primary motor cortex, association motor cortices and other frontal lobe structures.
Lateral geniculate nucleus is involved in sending information from:
vision to primary visual cortex
Medial geniculate nucleus is involved in sending information from:
auditory to primary auditory cortex
What nucleus is in the medial nuclear group?
the mediodorsal nucleus
The mediodorsal nucleus is involved in sending information from:
limbic and basal ganglia to the frontal cortex
What nucleus is in the anterior nuclear group?
Anterior Nucleus
Anterior nucleus is involved in sending information from:
mamillary body, hippocampus to cingulate gyrus
What cortices are involved in the integration of somatosensory?
Primary somatosensory cortex
somatosensory association cortex
heteromodal cortex
