14b. disconnect

Question 1

what is the Wada Test?

Answer 1

a test to see which side is language before surgery

Question 2

what is the corpus callosum?

Answer 2

-major structure in brain that allows communication between 2 hemispheres

Question 3

what is a common disconnection syndrome?

Answer 3

Commissurotomy (split brain)

patient can name object in right hand, but not left hand

Question 4

3 causes of disconnection syndrome

Answer 4

1. medically refractory generalized epilepsy
2. surgical callosotomy
3. developmental: agenesis of corpus callosum

Question 5

4 parts of the corpus callosum

Answer 5

1. rostrum
2. genu
3. body
4. splenium

Question 6

what are 2 effects of CC disconnection?

Answer 6

1. effects on language

2. effects on sensorimotor systems

Question 7

what is the consequence of anterior commissure disconnection

Answer 7

1. effects on olfaction

Question 8

what is alexia?

Answer 8

-patients able to talk, unable to read material presented in left hemifield
(words presented in left visual field)

Question 9

when does agraphia occur more?

Answer 9

anterior CC lesions

Question 10

what is unilateral agraphia?

Answer 10

motor apraxia

Question 11

what are 4 effects of disconnect syndromes on the sensorimotor system?

Answer 11

1. vision: visual effects + neglect
2. audition (left ear neglect)
3. transforming tactile info into language

Question 12

what is callosal agenesis

Answer 12

• born without a corpus callosum
• children: severe developmental disturbance
• adults: unexpected finding