Lecture 8 (cognition)

Question 1

left (dominant) hemisphere is dominant for?

right (non dominant) hemisphere is dominant for?

Answer 1

• language perception, speech

- spatial perception, recognition of faces, music

Question 2

what hemisphere is better at seeing details? versus seeing the hollistic picture?

Answer 2

• dominant

- non dominant

Question 3

The left hemisphere is dominant for most right-handed people and about ____ % of left- handed people. For the other 30% of left-handed people ?

Answer 3

• 70%

- about half have a dominant right hemisphere, and the other half have language functions in both hemispheres.

Question 4

what is the retinotopic organization of the visual cortex

Answer 4

central parts of visual field end up together in the primary visual cortex (info side by side on retina gets mapped in same organization). as info is passed to secondary visual cortex and onto the dorsal and ventral stream the retinotopy gets lost

Question 5

visual agnosia happens form damage where?

Answer 5

inferior temporal lobe (‘what’) and ventral occipital cortex (lingual and fusiform gyrus)
- usually bilaterally

Question 6

The patients can recognize objects by touch or sound, but not by sight. If asked, they can draw the object and describe its appearance. They appear to see the small details of the object, but are unaware of the overall shape.

Answer 6

visual agnosia

Question 7

inability to recognize faces. Patients with this disorder know that faces are faces, but cannot recognize individuals, even family members. They often cannot recognize a picture of themselves.

Answer 7

prosopagnosia

Question 8

damage to where leads to prospagnosia

Answer 8

right fusiform gyrus (fusiform face area)

Question 9

prospagnosia is often accompanied by?

Answer 9

some level of object agnosia

Question 10

Balint’s syndrome: damage to?

- symptoms (3)

Answer 10

• “where” stream/ posterior parietal
  1. Ocular apraxia: difficulty moving eyes to engage visual targets, especially in the visual field contralateral to lesion
  2. Simultanagnosia: inability to perceive multiple objects at the same time.
  3. Optic ataxia: inaccuracy in reaching for visual targets with the arm contralateral to
  lesion. This is also known as misreaching. (motor cortex sending out wrong commands because you do not know where object is in space)

Question 11

left Neglect is caused from damage to?

Answer 11

right posterior parietal (dorsal stream)

Question 12

slow laborous non fluent speech

Answer 12

brocas aphasia

Question 13

fluent language without meaning

Answer 13

wernickes aphasia

Question 14

global aphasia

Answer 14

damage to wernickes and brocas area

Question 15

inability to read (word blindness) (can still recognize words spelled aloud)

Answer 15

alexia

Question 16

with alexia, lesions are usually where? what do lesions prevent?

Answer 16

• stroke in posterior cerebral artery

- prevent visual information from reaching association areas of the left hemisphere

Question 17

difficulty with reading

Answer 17

dyslexia

Question 18

inability to write

Answer 18

agraphia

Question 19

difficulty writing

Answer 19

dysgraphia

Question 20

major areas the prefrontal cortex is connected to?

Answer 20

• secondary or association areas of the sensory cortex:
• motor areas: premotor cortex, supplementary motor area and frontal eye field
• BG: striatum receives heavy projection from PFC (influences motor output)
• Limbic system: especially orbitofrontal cortex, has direct and indirect connections to
  hippocampus, amygdala and hypothalamus

Question 21

dorsolateral and orbitofrontal cortex recieve info form what sensory modalities?

Answer 21

dorsolateral PFC receives somatosensory, auditory, and visual – most areas receive input from at least two senses. Orbitofrontal cortex receives olfactory, gustatory, and visceral sensory information.

Question 22

overall symptoms of dementia

Answer 22

• memory deficits
• language deficits
• inability to control emotions
• inability to problem solve
• personality changes