CH 7: Proprioception, Touch & Tactile Discrimination Flashcards
tactile sensations are complex because they involve both ___ and ___?
tactile stimuli can also be ____ or ____?
a blending of light cutaneous contact (touch)
variable degrees of pressure depending on the intensity of the stimuli
can also be static or dynamic
tactile sensations are complex because they involve both ___ and ___?
tactile stimuli can also be ____ or ____?
a blending of light cutaneous contact (touch)
variable degrees of pressure depending on the intensity of the stimuli
can also be static or dynamic
tactile sensation is divided into ___ and ____?
light touch
tactile discrimination
light touch involves?
detection of contact with the skin
tactile discrimination involves?
perception of the size and shape of objects
tickling and itching sensations are related to ___?
related to pain and not to tactile sense
what are Von Frey hairs?
fine hairs of graduated stiffness used to apply stimuli at calibrated intensities to the skin
what are 4 methods used to test tactile discrimination?
1- stereognosis
2-two point discrimination
3- complex tactile discrimination
4- flutter-vibration
what is stereognosis?
eyes closed
identify common small objects placed in one hand
what is two point discrimination?
determine whether one touch stimulus or two simultaneous stimuli have been applied to the skin
what is complex tactile discrimination?
ask subject to identify numbers or letters written on the surface of the skin with a blunt object
what is flutter-vibration?
an important component of tactile sensation
flutter- is a feeling of repetitive movement
vibration– is a more diffuse and penetrating feeling of “humming” when the base of a vibrating fork contacts a bony prominence of the body
proprioceptive sensation includes both:
static limb position
kinesthesia- the sense of movement
what are the 2 different sets of sensory pathways in the SC that provide essential information to the brain about muscle action, joint position and the objects with which a person is in contact?
1: Pathways that project to the cerebellum
2: Pathways that project to the cerebral cortex
** both use mechanoreceptors
what 3 pathways project to the cerebral cortex by way of the thalamus?
- spinal lemniscus
- spinothalamic tract
- lateral cervical system
information carried by these pathways is perceived consciously
what 3 pathways project to the cerebral cortex by way of the thalamus?
- spinal lemniscus
- spinothalamic tract
- lateral cervical system
information carried by these pathways is perceived consciously
tactile sensation is divided into ___ and ____?
light touch
tactile discrimination
light touch involves?
detection of contact with the skin
tactile discrimination involves?
perception of the size and shape of objects
tickling and itching sensations are related to ___?
related to pain and not to tactile sense
what are Von Frey hairs?
fine hairs of graduated stiffness used to apply stimuli at calibrated intensities to the skin
what are 4 methods used to test tactile discrimination?
1- stereognosis
2-two point discrimination
3- complex tactile discrimination
4- flutter-vibration
mechanoreceptors are mostly innervated by:
large diameter myelinated fibers, with the exception of free nerve endings
the cell bodies of these peripheral nerve fibers are in the dorsal root ganglia and their central processes enter the medial side of the dorsal root zone
what is two point discrimination?
determine whether one touch stimulus or two simultaneous stimuli have been applied to the skin