cerebellar and proprioception Flashcards
what are the principle receptors for proprioception?
neuromuscular and neurotendinous spindles
golgi tendon organ
4 joint mechanoreceptors
where does the proprioceptive pathway ascend and synapse?
ascends the spinal cord ipsilaterally in posterior columns
synapses in lower brainstem
dysdiadochokinesia indicates possible?
cerebellar dysfunction
abnormal joint position test indicates possible?
posterior column disease
multimodal sensations come from?
parietal lobe association cortex
when a primary sensory modality is not working, the deficit is referred to as?
anesthesia
analgesia
specific stimuli excite nerve end organs that are attached to DRG. with enough stimuli the impulse travels from peripheral back to nerve root. What is the path it travels?
neuron 1 (lateral or medial) synapses with neuron 2
neuron 2 crosses midline and ascends a CNS lemniscus carrying an impulse to nucleus ventralis posterolateralis and nucleus ventralis posteromedialis of thalamus
neuron 2 transfers impulse to neuron 3 at thalamic nuclei
neuron 1 lateral and medial divisions
lateral- superficial
medial- deep
what is neuron 3 AKA
thalamocortical radiation
where does the thalamocortical radiation travel?
to somesthetic cortex located on post central gyrus of parietal lobe
where does body reorganization and localization of stimuli take place?
somesthetic cortex
where is the somesthetic cortex located?
post central gyrus of parietal lobe
lower body info ascends?
medially
upper body info ascends?
laterally
what are the testable deep sensations?
pain
touch
proprioception
what are the superficial/ exteroreceptive sensations?
pain
temp
light touch
who studied dermatome distributions based on herpetic lesions and trauma involved with spinal cord?
Head
who performed isolated root sections and noted remaining sensibility after certain roots were cut?
Sherrington and Foerster
who determined distribution of dermatomes by making use of antidromic responses (reverse conduction of impulses?
Foerster
who argued against overlap of dermatomes and altered dermatome charts?
Keegan
what is thigmesthesia?
non discriminating touch
where does the pathway for light touch ascend? same as pain
slightly myelinated fibers that ascend to anterior lateral columns of cord to thalamus
what is topesthesia?
discriminating well localized touch
where is topesthesia carried to?
posterior spinal cord
due to overlap and duplication of function, which sensation is least desirable to used for evaluation?
touch
what tissues are devoid of nociceptors?
articular cartilage
inner annulus and nucleus of IVD
synovial membranes
nociceptive impulses travel where and project where?
ascend with myelinated A delta and unmyelinated C fibers and project to dorsal lateral fasciculus
fibrillations can not be seen?
by the naked eye
fasciculations can be seen
motor cortex neurons controlling CN descend along what tract and synapse where?
corticobulbar tract to brainstem nuclei and synapse on LMN
motor cortex neurons not involving CN along which tract?
corticospinal
what are the 3 areas of integrity that are assessed for muscle?
volume
tone
strength
