9 Cortical Localization 2

Question 1

Lesions of optic nerve yield?

Answer 1

monocular blindness

Question 2

lesions of optic radiations yield?

Answer 2

homonymous quadrantanopsia/hemianopsia

Question 3

macular vision (in V1) is located where?

Answer 3

occipital pole

Question 4

dorsal bank of V1 has lower or upper field of vision?

Answer 4

lower

Question 5

a scotoma is?

Answer 5

small blind spot (damage to small spot of V1)

Question 6

V2 surrounds V1 and responds to?

Answer 6

complex patterns

Question 7

V3 surrounds V2 and responds to? (dorsally and ventrally?)

Answer 7

• ventral V3=pattern and object recognition, and long-term storage of visual info
• dorsal V3=large-scale motion, placing objects in external space, and control of saccades

Question 8

MT (unknown abbreviation) is another word for?

Answer 8

V5 (visual cortex 5)

Question 9

Where do the two visual streams separate? (dorsal & ventral)

Answer 9

V3

Question 10

Where does ventral V3 get input from?

Answer 10

gets input from mostly V2

Question 11

Where does dorsal V3 get input from?

Answer 11

gets input from V1, V2

Question 12

V4 is located where? Consists of dorsal or ventral stream?

Answer 12

• Posterior inferior temporal lobe

- Ventral stream

Question 13

V5 is located where?

Answer 13

Posterior end of middle temporal gyrus (consists of dorsal stream)

Question 14

Left V4 does what function?

Answer 14

Notices color, texture, shape, processes symbols for language/writing

Question 15

Right V4 does what function?

Answer 15

non-verbal perception, including face recognition

Question 16

A ventral visual stream lesion (ventromedial occipitotoempor cortex, specifically fusiform/lingual gyri) gives what problems?

Answer 16

visual agnosia (can’t recognize objects), alexia (can’t read) with agraphia (can’t write)

Question 17

V5 does what function?

Answer 17

Sends info to FEF (???) and posterior parietal cortex, for motion perception & noticing where objects are in space

Question 18

Ballint’s syndrome (V5 lesion) consists of?

Answer 18

-simultanagnosia (can’t see more than 1 object at a time), optic ataxia (can’t move hand toward object), ocular apraxia (can’t voluntarily gaze at objects)

Question 19

What usually causes Ballint’s syndrome?

Answer 19

Bilateral lesion of posterior parietal cortex near temporoparietooccipital junction, often a watershed infarct between MCA/PCA

Question 20

Primary auditory cortex is located where? Receives input from which ear?

Answer 20

Heschl’s gyrus

-bilateral w/ contralateral dominance (via medial geniculate body)

Question 21

auditory belt cortex surrounds what?

Answer 21

Primary auditory cortex

Question 22

Which side of auditory belt cortex does temporal decoding? Which does spectral decoding?

Answer 22

• Left (can fill gaps in speech)

- Right (can fill gaps in melody) (mnemonic: SPECTERS are always RIGHT!)

Question 23

Wernicke’s area does what?

Answer 23

Decodes verbal info (left lesion=sensory aphasia, i.e. can’t understand speech)

Question 24

Right hemisphere equivalent of Wernicke’s area (NOT called Wernicke’s area though) does what?

Answer 24

Prosody. (lesion=sensory aprosodia, i.e. can’t understand pitch/tone to perceive whether someone is happy/mad)

Question 25

Which portion of Wernicke’s area is responsible for unique identifiers?

Answer 25

Anterior. Lesions producing anomia are worst here near the pole. (Posterior is for category names)

Question 26

Auditory “What and where” paths refers to what?

Answer 26

• Recognition of words

- location of the sound source

Question 27

Lesions of postcentral gyrus (primary somatosensory cortex) produce what?

Answer 27

agraphesthesia (can’t feel what letter is written on your skin), astereognosis (can’t identify object by touch), loss discriminative touch but only a diminution of pain/temp sensation

Question 28

In primary sensory cortex, regions 1, 2, 3a, 3b contain what info?

Answer 28

1-texture
2-size/shape
3a-proprioception
3b-touch, pressure, vibration (commonly thought of as “primary” sensory cortex)

Question 29

Right Inferoro Parietal Lobule has what main function?

Answer 29

Self-perception & position of the body in external space (including visuospatial tasks). Damage on right=hemi-neglect syndrome. (left body & world ignored.)

Question 30

Constructional apraxia is due to what lesion?

Answer 30

Dorsomedial somatosensory association area.

Question 31

What region has 4 visual association areas?

Answer 31

Parietal operculum (S2,S3, S4, and ?)

Question 32

Tactile agnosia is due to a lesion where?

Answer 32

Ventromedial somatosensory assocation area

Question 33

Damage to Left Inferior Parietal Lobule causes what defects?

Answer 33

• Agraphia
• Acalculia
• Finger Agnosia
• Impaired verbal working memory

Question 34

The left inferior parietal lobule is mainly involved in what functions?

Answer 34

• Language functions

- Specializes in fractionated things (not holistic like right side)

Question 35

Which brain region is the last to fully myelinate?

Answer 35

Medial parietal lobule

Question 36

Medial parietal lobule shows its highest activity when? What is its function?

Answer 36

• When awake

- Self-consciousness

Question 37

What are the 4 frontal lobes?

Answer 37

• Motor/premotor
• Broca’s
• Dorsolateral prefrontal (memory)
• Medial prefrontal