Question | Answer |
presentation of damaged to trochlear nerve | unopposed action of superior rectus causes elevation of the eye, while unopposed inferior oblique will cause extortion of the eye.
Patient will walk in with head tilted away from damaged trochlear nerve. |
Effects of damage to oculomotor nerve | "down and out" look |
Damage to abducens nucleus | 1. Ipsilateral eye adducted at rest. It cannot be abducted
2. loss of interneurons; inability to contract contralateral medial rectus. 2 consequences are end gaze nystagmus and inability to look towards side of lesion.
(abducens nerve symptoms + mo |
Damage to abducens nerve | 1. Ipsilateral eye adducted at rest. It cannot be abducted |
Internuclear Opthalmoplegia | Due to damage of MLF --> loss of control of the contralateral medial rectus, thus a |
Clarke's nucleus | They give rise to the dorsal spinocerebellar tract. (C8-L2)
group of interneurons found in Lamina VII, also known as the intermediate zone, of the spinal cord. |
Accessory cuneate nucleus | The equivalent of clarke's nucleus. It gives rise to the cuneocerebellar tract.
Contained by the caudal medulla |
The Purkinje cell dendritic tree is | planar and oriented orthogonal to the long axis of the folium |
fastigial nucleus | -->lateral vestibular nucleus (lateral vestibulospinal tract)-->axial muscles for balance control |
What is the only source of climbing fibers? | Inferior olivary nucleus |
Histochemical staining of striatal bridges | Stain positive for AchE-->a marker for Ach or enkephalin |
Gross changes in Huntington's | A enlargement of the lateral ventricles on coronal cut because of atrophy of the caudate nucleus |
ventral pallidum | part of the limbic loop. This area is found caudal (inferior) to the anterior commissure (and the globus pallidus external) on a coronal cut. It is mainly rostral to GPi. |
Pallidotomy | destruction of the GPi improves parkinsonian signs in those refractory to treatment. GPi is a major output nuclei. |
How can you get Hemiballism | Hemiballism, characterized by ballistic movements, can be induced by destroying the contralateral subthalamic nuclei. |
Layers II and III | cortical association neurons, which project to ipsilateral cortex, and callosal neurons which cross to contralateral cortex via the corpus callosum |
layer V | descending projection neurons; to brainstem, striatum and spinal cord. |
Layer VI | descending projection neurons; to the thalamus |
Substancia nigra reticularis | an intrinsic nuclei of the basal ganglia--->it is tonically inhibiting (superior colliculus) eye movement and stops firing when saccade is desired |
Smooth pursuit requires | attention--Any disorder which impairs attention impairs SP-- dorsolateral pontine nuclei and cerebellum needed to calculate target velocity |
Basal nucleus of meynart (basal forebrain) is | involved in vision and is main cholinergic neuromodulatory pathway in CNS. Adjacent to the anterior perforated substance
It can be affected in Alzheimer's |
Paraventricular nucleus | a nucleus of the hypothalamus that is important in both endocrine and autonomic processes. Parvocellular=anterior pituitary control. Magnocellular=oxytocin and ADH |
What signal is needed for the survival of projections of the arcuate nucleus to the PVN | leptin: Hence PVN has more excitatory connections (lacks arcuate inhibition), there is more NPY/AgRP and this excitation of anabolic pathways |