Auditory Pathway

Question 1

What are the auditory ossicles of the middle ear?

Answer 1

• Malleus.
• Incus.
• Stapes.

Question 2

The cochlear nerve runs through what to reach the cochlea of the inner ear?

Answer 2

Internal acoustic meatus.

Question 3

How many turns are in the spiral of the cochlea?

Answer 3

2.5

Question 4

The organ of Corti contains what?

Answer 4

Inner and outer hair cells.

Question 5

What is the Spiral Ganglion of the Cochlea?

Answer 5

A group of bipolar neurons stimulated by hair cells. They carry APs from the Organ of Corti to the cochlear nuclei in the pons.

Question 6

Superior to the cochlear nuclei, input is essentially what?

Answer 6

Bilateral.

Question 7

Structures important in sound localisation and as relays for stapedial and tensor tympani reflexes.

Answer 7

• Superior olivary nucleus.

- Nucleus of lateral lemniscus.

Question 8

Tonotopic organisation is present where?

Answer 8

The Auditory Cortex.

Question 9

Fibres carrying information regarding low frequency sound end in which part of the auditory cortex?

Answer 9

The anterolateral part.

Question 10

Fibres carrying information regarding high frequency sound end in which part of the auditory cortex?

Answer 10

The posteromedial part.

Question 11

What may arise as a result of trauma to Broca’s area?

Answer 11

• Difficulty in producing language (using few words, only saying the most important words in a sentence).
• However, there is usually no difficulty comprehending language.

Question 12

What is the name of the condition arising from damage to Broca’s area?

Answer 12

Broca’s/ motor/ expressive aphasia.

Question 13

What may arise as a result of trauma to Wernicke’s area?

Answer 13

• Difficulty comprehending language.
• Using words out of order.
• Meaningless words.

Question 14

What is the name of the condition arising from damage to Wernicke’s area?

Answer 14

Wernicke’s/ sensory/ receptive aphasia.

Question 15

Maintaining equilibrium requires information from what?

Answer 15

• Vision.
• Proprioception.
• Vestibular apparatus (labyrinth).

Question 16

How many semi-circular canals in the inner ear?

Answer 16

3 in each ear.

Question 17

What nerve is most associated with hearing?

Answer 17

Cochlear nerve.

Question 18

What nerve is most associated with balance?

Answer 18

Vestibular nerve.

Question 19

Name 3 areas upon which vestibular information has been found to converge?

Answer 19

• Area of parietal cortex just posterior to the area of the postcentral gyrus that represents the hand and mouth.
• Area just rostral to the primary auditory cortex.
• Posterior insular cortex.

Question 20

Due to the lens, objects are projected onto the retina how?

Answer 20

Reversed and upside down.

Question 21

Each optic tract, lateral geniculate nucleus, optic radiation and visual cortex deals with visual information from which visual field?

Answer 21

The contralateral visual field.

Question 22

Output of the superior colliculi is to?

Answer 22

• Nuclei of CN III, IV and VI.
• Motor nucleus of VII.
• Spinal cord.

Question 23

The lower visual field is projected to where?

Answer 23

The gyrus superior to the calcarine sulcus.

Question 24

The upper visual field is projected to where?

Answer 24

The gyrus inferior to the calcarine sulcus.

Question 25

The macula projects to which pole of the visual cortex?

Answer 25

The posterior pole.

Question 26

What is significant about the macula and its relationship with the visual cortex?

Answer 26

The macula occupies a much greater proportion of the cortex relative to the size of the visual field it covers.

Question 27

Fibres of the geniculocalcarine tract initially form what?

Answer 27

Part of the internal capsule.

Question 28

Fibres of the geniculocalcine tract carrying visual information from the upper half of the visual field loop around what?

Answer 28

Anteriorly around the temporal part of the lateral ventricle in MEYER’S LOOP.

Question 29

Where do fibres of the geniculocalcine tract carrying visual information from the upper half of the visual field end after Meyer’s loop?

Answer 29

Below the calcarine sulcus.

Question 30

The visual cortex generally provides for eye movements in response to what?

Answer 30

Visual stimuli e.g. tracking moving objects.

Question 31

The frontal eye fields control what?

Answer 31

“Movements of command” i.e. movements independent of moving visual stimuli.

Question 32

How do tracking movements differ from movements of command?

Answer 32

• Tracking movements tend to be smooth.

- Movements of command tend to be jumpy (Saccadic).

Question 33

What term is given to the jumpy movements generally seen in movements of command of the eye?

Answer 33

Saccadic.

Question 34

If a light is shone into the right eye, what is the resultant direct light reflex?

Answer 34

• The right pupil constricts.

Question 35

If a light is shone into the right eye, what is the resultant consensual light reflex?

Answer 35

The left pupil constricts.

Question 36

The pretectal fibres of the consensual light reflex project where?

Answer 36

Bilaterally to the Edinger-Westphal nucleus.

Question 37

In contrast to the pupillary light reflex, the accommodation reflex requires what?

Answer 37

Input to the oculomotor and Edinger-Westphal nucleus from the visual cortex.

Question 38

What is hemianopia?

Answer 38

Blindness for half the field of vision in one or both eyes.

Question 39

A term for the same visual field loss in both eyes.

Answer 39

Homonymous.

Question 40

A term for opposite visual field loss in both eyes.

Answer 40

Heteronymous.

Question 41

The name given to the cerebral hemisphere which “takes the lead” in certain higher functions.

Answer 41

Dominant hemisphere.

Question 42

For most truly right-handed people, which hemisphere is usually dominant for language?

Answer 42

The left cerebral hemisphere.

Question 43

Association fibres connect to cortical sites located where?

Answer 43

In the same cerebral hemisphere.

Question 44

Commissural fibres connect what?

Answer 44

One cerebral hemisphere to the other, usually connecting areas with similar function.

Question 45

Projection fibres connect what?

Answer 45

Hemispheres to deeper structures e.g. thalamus, corpus striatum, brain stem and spinal cord.