Lateralization of Function

Question 1

Describe the differences between the right and left hemisphere functions

Answer 1

Left: linear thinking mode - writing, language, speech, etc.

Right: holistic thinking mode - emotions, imagination, spatial awareness, etc.

Question 2

Which parts of the body do the left and right hemisphere control? (2)

Answer 2

Left: skin receptor and muscles on the right side of the body

Right: skin receptor and muscles on the left side of the body

Question 3

Describe auditory processing in the left and right hemispheres (2)

Answer 3

Each hemisphere gets auditory info from BOTH ears

but

slightly stronger from the contralateral ear
(LH - right ear)
(RH - left ear)

Question 4

Describe taste and smell processing in the left and right hemisphere (3)

Answer 4

BOTH hemispheres get taste info from BOTH sides of the tongue

Left hemisphere receives info from left nostril

Right hemisphere receives info from right nostril

Question 5

Describe the control of facial muscles in the left and right hemispheres

Answer 5

Each hemisphere controls facial muscles on BOTH sides of the face

Question 6

Describe visual processing in the right and left hemispheres (4)

Answer 6

RIGHT visual field projects to the LEFT half of BOTH retinas

LEFT visual field projects to the RIGHT half of BOTH retinas

Axons from RIGHT half of the LEFT retina cross to the RIGHT hemisphere

Axons from the LEFT half of the RIGHT retina cross to the LEFT hemisphere

Question 7

How do the left and right hemispheres exchange info? (3)

Answer 7

• corpus callosum
• anterior commissure
• hippocampal commissure

Question 8

Define lateralization of function

Answer 8

division of labour between the 2 hemispheres

Question 9

Which hemisphere is dominant for speech in left/right-handed people? (2)

Answer 9

95% right handed people - left hemisphere is dominant

68% left handed people - right hemisphere is dominant

Question 10

How would the left and right hemispheres function w/out a corpus callosum? (2)

Answer 10

• left hemisphere could only react to info from the right side
• right hemisphere could only react to info from the left side

Question 11

What are the effects of cutting the corpus callosum? (3)

Answer 11

• Prevents exchanging of info
• Struggle on unfamiliar tasks
• Can do things with hands that nobody else can’t (e.g., rotating both hands in opposite directions simultaneously

Question 12

What is the right hemisphere capable/not capable of when the corpus callosum is cut? (2)

Answer 12

Capable: language comprehension
Not capable: language production