chapters 11-12: cerebral asymmetry, differences in cerebral organization

Question 1

What does laterality mean?

Answer 1

Difference in function between the hemispheres

Question 2

(Left/Right) hemisphere is specialized for language, controls the (left/right) side of the body.

Answer 2

Left, right

Question 3

(Left/Right) hemisphere is specialized for nonverbal information, controls the (left/right) side of the body.

Answer 3

Right, left

Question 4

Lateralization is (relative/absolute).

Answer 4

Relative (both hemispheres involved in almost all behaviours).

Question 5

What is the functional name of Wernicke’s Area and how/where is it lateralized?

Answer 5

Wernicke’s Area (planum temporale): secondary auditory cortex; left-lateralized for most.

Question 6

What is the functional name of Heschel’s Gyri and how/where are they lateralized?

Answer 6

Heschel’s Gyri: primary auditory cortex; right-lateralized in most. Also two gyri in right vs one gyrus in left.

Question 7

Motor and sensation functions are mostly (symmetrical/asymmetrical), language function is (symmetrical/asymmetrical).

Answer 7

symmetrical, asymmetrical

Question 8

How did early epilepsy treatment lead to mapping the cortex (and discovering lateralization)?

Answer 8

Treatment was removing parts of brain, care had to be taken to remove correct areas and not affect other function. Lateralization discovered via mapping.

Question 9

Weak stimulation of left frontal or temporal lobes (facilitated/inhibited) speech production. Strong opposite.

Answer 9

facilitated

Question 10

Describe the experimental technique of double dissociation and its purpose.

Answer 10

Double dissociation: two functions, two patients with lesions of associated brain regions. If functions impaired in each as expected, double dissociation confirmed.

Purpose: To show that particular function is associated with particular brain region. Also shows separate organization between two functions of interest.

Question 11

In split-brain patients, information presented to (left/right) visual field cannot be verbalized about directly.

Answer 11

left

Question 12

In split-brain patients, information processed by the (left/right) hemisphere is implicitly processed, other hemisphere makes up a reason for behaviour.

Answer 12

right

Question 13

In split-brain patients, the (left/right) hemisphere acts as the interpreter due language lateralization.

Answer 13

left

Question 14

What is the process and purpose Wada Test?

Answer 14

Sodium amobarbital (paralytic) is administered (initially via cartoid, later femoral catheter) to one hemisphere for the purposes of functional testing.

Question 15

__% of right-handers are left-hemisphere language dominant, __% of left-handers.

Answer 15

98, 70

Question 16

__% of non-right-handers show lack of language lateralization (bilateral speech).

Answer 16

15

Question 17

What is tachistoscopic presentation and how is it used to determine lateralization.

Answer 17

Tachistoscopic presentation: images presented to individual visual field for less than 50 microseconds using tachistoscope. Accuracy of information compared between hemispheres to determine lateralization.

Question 18

Faces better processed by (left/right) hemisphere, visuospatial information: (left/right), language: (left/right).

Answer 18

right, right, left

Question 19

How is the auditory system differentiated compared to left/right visual fields?

Answer 19

Auditory system is less differentiated.

Question 20

When provided with dichotic inputs, which ear’s input is prioritized?

Answer 20

The contralateral input.

Question 21

Somatosensory and motor pathways are almost entirely (ipsi/contra)lateral.

Answer 21

contralateral

Question 22

(left/right)-handers better at understanding braille due language processing being [other]-lateralized.

Answer 22

left-handers

Question 23

Mouth movements begin on (left/right) side of face, emotions displayed more strongly on (left/right) side.

Answer 23

right, left

Question 24

How do specialization vs interaction theories differ?

Answer 24

Specialization: different hemispheres have unique functions

Interaction: though one hemisphere may be better at a task, both cooperate

Question 25

What is one’s cognitive set? How is it relevant to lateralization?

Answer 25

Cognitive set: biases in how individual’s approach problems. Affects results of lateralization tests due individual preference over cerebral organization.

Question 26

In primates, rapid uni-manual movements favour which hemisphere? whole-body movements?

Answer 26

Right specialized for rapid uni-manual movements, left for whole-body movements.

Question 27

When is handedness first apparent? what percentage are right handed?

Answer 27

10 weeks post-conception, 90% in writing, 70-90% for other functions.

Question 28

Do righties and lefties showcase the same degree of hand dominance lateralization?

Answer 28

No. Righties more lateralized.

Question 29

__% of lefties have leftie language, __% have right language organization (weird), __% bilateral.

Answer 29

70, 15, 15