Michaels

Question 1

hemianopsia

Answer 1

a decreased vision or blindness (anopsia) in half the visual field of one or both eyes, usually on one side of the vertical midline. The most common causes of this damage are stroke, brain tumor, and trauma.

Question 2

omonymous vs. heteronymous visual deficits

Answer 2

Damage to the optic tract: Runs from the optic chiasm to the lateral geniculate nucleus (LGN).

Damage at this point is “homonymous” – defects involve one visual field

or

“heteronymous” involves parts of both visual fields so defects are non-overlapping – occurs at chiasm

Question 3

meyer’s loop

Answer 3

Axons of lateral geniculate nucleus (thalamus) representing the upper visual fields travel forward into the temporal lobe as Meyer’s loop before turning toward the occipital cortex.

Question 4

quadrantanopsia

Answer 4

defective vision or blindness in approximately one-fourth of the visual field

Question 5

retinotopic organization

Answer 5

the visual field organization seen in the lateral genticulate nuclues in the thalamus

Question 6

Taste transmission of the tongue is carried to the brainstem via two main nerves:

Answer 6

• facial/chorda tympani in the anterior 2/3 of the tongue
• glossopharyngeal nerve on the posterior third.
• touch/temp sensation on the tongue is provided by the trigeminal nerve in the front end and glossopharyngeal at the back.

Question 7

The vagus nerve provides “taste” sensation to the ______ region (larynx, epiglottis) but we don’t perceive information from these taste buds as sweet, salt, bitter, etc. Instead, they appear to be involved with detecting irritants that cause us to cough or gag.

Answer 7

throat

Question 8

Taste Bud Afferents… location and path

Answer 8

• Primary afferents that innervate taste buds reach the brainstem with VII (anterior 2/3 of tongue – chorda tympani), IX (posterior 1/3 of tongue) and X (epiglottis and larynx).
• They travel within the brainstem in the solitary tract and end in the nucleus of the solitary tract, mostly in the rostral end –> 3 paths (thalamus –> VPM –> insula; hypothalamus; and reticular formation (gagg, cough reflex)

Question 9

gustatory primary afferents

Answer 9

CN VII, IX, X –> solitary tract (medulla) –> solitary nucleus