Misc. Flashcards
What is and isn’t a part of the lentiform nucleus?
Putamen and globus pallets ARE
Caudate is NOT
Which trigeminal nucleus is analogous to the ventral horn of the spinal cord?
trigeminal motor nucleus
Which trigeminal nucleus is analogous to the dorsal column nuclei of the spinal somatosensory system?
principal sensory nucleus
Which trigeminal nucleus is the site of termination of C and A-delta fibers that descend caudally after entering the brainstem and form the descending root of the trigeminal nerve?
spinal trigeminal nucleus
Which trigeminal nucleus is derived from neural crest cells and innervates proprioceptors on the gums and jaw?
mesencephalic trigeminal nucleus
Brachiomotor nuclei
innervate striate muscles derived from brachial mesenchyme (neural crest).
Nucleus Ambiguus, Facial nerve (CN7) and TG motor nucleus (CN5)
Middle cerebellar peduncle
Information from the cerebral cortex through the pons to the cerebellum
Pons to cerebellum
Inferior cerebellar peduncle
Information from the spinal cord to the cerebellum, interconnecting the cerebellum with the vestibular nucleus and inferior olive
The crus cerebri (cerebral peduncle) marks the exit point for which cranial nerve?
Oculomotor
ventral border of the midbrain
Inferior cerebellar peduncle
conveys spinal cord information to the cerebellum and interconnects the cerebellum with the vestibular nuc. and inferior olive
Middle cerebellar peduncle
the route by which information from the cerebral cortex gets to the cerebellum via the pontine nuclei
Superior cerebellar peduncle
route by which the cerebellum gets information back to the cerebral cortex (via the thalamus)
Axons originate in dentate nucleus and end in contralateral VA/VL
Also axons originating in interposed nucleus and ending at red nucleus
Pyramidal tract lesion symptoms
spastic paralysis
Spinothalamic tract lesion symptoms
loss of pain and temperature
Dorsal column-medial lemniscus lesion symptoms
loss of 2-pt. discrimination, fine touch, and conscious proprioception
spinal trigeminal tract & nucleus
Loss of pain and temp for the head
Combined deficit of the pyramidal tract and medial lemniscus likely indicates a lesion where?
Medulla
A combined spinothalamic and medial lemniscus type deficit likely indicate a lesion where?
Midbrain
AS BM
Alar plate= sensory (lateral)
Basal plate= motor (medial)
Branchiomotor nuclei
Innervate striate muscles derived from the branchial mesenchyme (of neural crest origin)
trigeminal motor nucleus, the facial (motor) nucleus and the nuc. ambiguus
Where does the corticospinal tract decussate?
Base of medulla
Where does the DCML decussate?
mid-medulla
Where does the AL or spinothalamic tract decussate?
spinal cord
Gag reflex
Afferent= IX sensory fibers Efferent= X nucleus ambiguous
Jaw jerk reflex
Afferent = mesencephalic nucleus of V (stretch receptors in masseter) Efferent = main motor nucleus of V
Corneal blink reflex
Cornea is touched by a foreign object, both eyes blink
Afferent = spinal nucleus of V
Efferent = motor nucleus of VII
Pupillary light reflex
Afferent= CN II Efferent= EW nucleus (III)
Facial nerve lesions (UMN signs vs LMN signs)
UMN= top of face is innervated by both sides, so you will only see a deficit on the contralateral lower part of face
LMN= By this pt, no dual innervation, so have entire contralateral hemiparalysis of face
Lateral lemniscus
Carries bilateral auditory info
Pontine nuclei- where do the axons terminate?
Contralateral cerebellum
Involved in motor coordination
Cerebral peduncle- origin and termination
Origin: various areas of the cortex (including motor cortex)
Termination: Contralateral spinal cord, pontine nuclei, montor nuclei in brainstem
A lesion in the left MLF will cause what?
When moving eyes towards rt, left eye fails to move medially
Left eye will move medially during convergence
Medial geniculate nucleus- where do axons originate and what info?
Axons originate in inferior colliculus
Bilateral auditory info
Red nucleus- where axons originate?
Axons originate in contralateral cerebellum
Deep cerebellar nuclei- what kind of input do they receive
Inhibitory input from purkinje cells
Excitatory input from pons and spinal cord
Dentate nucleus input and output
Input from cerebellar cortex
Project via superior cerebellar peduncle to cerebellar target nuclei
Projects mostly VA/VL nucleus in thalamus
Inferior olivary nucleus input and output
Project via the contralateral inferior cerebellar peduncle to cerebellar cortex where they end as climbing fibers
Where are ITDs, ILDs, spectral cues, and contralateral sound sources encoded?
ITDs : medial superior olive
ILDs: lateral superior olive
spectral cues: dorsal cochlear nucleus
contralateral sound sources: inferior colliculus.
A unilateral lesion confined to the right superior olive
Will affect sound localization
If you had your forearm flexed (bent at the elbow joint) with half-maximal tension in your biceps muscle (an arm flexor) and someone unexpectedly pulled your hand and caused a rapid, passive extension of your forearm
During the extension, alpha motor neurons to the biceps muscle would receive increased
excitatory synaptic input as a result of increased biceps Ia afferent activity
supplementary motor area (SMA)
Electrical stimulation in conscious animals causes complex movements often involving several joints.
“Thinking” about performing a movement (for example, mental rehearsal of a task) will cause increased activity within this area in humans (as indicated by blood flow
measurements).
Some neurons located there send axons directly into the corticospinal tract.
What projects to the globus pallidus without synapsing somewhere else first?
Putamen, Subthalamic nucleus, Caudate
What don’t complex cells in the primary visual cortex care about?
position
Hemiballismus
lesion in subthalamic nucleus
Loss of excitatory input to the medial (internal) pallidal segment
