Somatosensory Systems Flashcards
What is the purpose of the circle of Willis?
Prevents reduced blood flow to brain when one artery compressed
Which areas are supplied by the middle cerebral artery?
Most of lateral surface of hemisphere
Broca’s area and Wernicke’s area in left hemisphere
Upper limb function in both hemispheres
Which area is supplied by the anterior cerebral artery?
Anterior medial surface of hemisphere - contralateral lower limb function
Which area is supplied by the posterior cerebral artery?
Posterior medial surface of hemisphere - posterior visual cortex and temporal cortex - contralateral visual field function
Where is the nucleus basalis of Meynert and what is its role?
In basal forebrain
Supplies cholinergic fibres to neocortex
Which afferent fibre types run up and down Lissauer’s tract?
C fibres
Which afferent fibre types run up and down the dorsolateral columns?
Myelinated afferents
What is allodynia?
Mechanoceptive fibres activate nociceptive pathways in spinal cord
What is the role of the raphe nuclei?
Project serotonergic fibres over CNS
What is the role of the locus coerulus?
Projects NAergic axons over CNS
What is cranial nerve I and what is its role?
Olfactory
Smell
What is cranial nerve II and what is its role?
Optic
Vision
What is cranial nerve III and what is its role?
Oculomotor
Eye movement
What is cranial nerve IV and what is its role?
Trochlear
Downward and lateral eye movement
What is cranial nerve V and what is its role?
Trigeminal
Sensory info from face, chewing
What is cranial nerve VI and what is its role?
Abducens
Lateral eye movement
What is cranial nerve VII and what is its role?
Facial
Expressions, tear and saliva secretion, taste
What is cranial nerve VIII and what is its role?
Vestibulocochlear
Hearing, equilibrium sensation
What is cranial nerve IX and what is its role?
Glossopharyngeal
Taste, carotid sinus bp and O2 detection
What is cranial nerve X and what is its role?
Vagus
Swallowing, GI tract secretion and motility, slows heart rate, ear and larynx afferents, aorta afferents
What is cranial nerve XI and what is its role?
Accessory
Swallowing, speech - via vagus
What is cranial nerve XII and what is its role?
Hypoglossal
Tongue movements
What are the branches of the trigeminal nerve and which areas do they innervate?
Opthalmic (V1) - Eye, forehead
Maxillary (V2) - cheek
Mandibular (V3) - lower jaw
