Problem 7

Question 1

Korsakoffs syndrome

Answer 1

Refers to the most common form of amnesic syndrome, which entails 2 different kings of amnesia

1. Anterograde amnesia
   - -> inability to form new LTMs w/ STM intact
2. Retrograde amnesia
   - -> loss of LTM that dates back

BUT: EM remains intact, but can’t create new ones

Question 2

What causes Korsakoffs syndrome ?

Answer 2

The toxic effects of alcohol + thiamine deficiency caused by malnutrition in heavy drinkers

–> ultimately resulting in the destruction of

1. mammillary bodies
2. dorso-medial nucleus of the thalamus
3. frontal lobes

Question 3

Korsakoffs syndrome basically sounds like a complete loss of memory.

How can one then go about a daily life ?

Answer 3

Classical conditioning + procedural learning remains intact

e.g.: learning to drive or use a computer could be learned

Question 4

Patient H.M.

Answer 4

His medial temporal lobes including both hippocampi were bilaterally removed to counteract his severe seizures.

–> left him with permanent memory loss

Question 5

Are amnesic patients conscious ?

Answer 5

This is debatable

–> sure they are awake + responsive, but w/o the ability to make new memories the person is stuck in the past and unrelated to the events + people around him or her of the present

Question 6

Antons syndrome

Anosognosia

Answer 6

Refers to a condition where the patient is blind but insist that they can see

Question 7

Hemifield neglect/

Unilateral neglect

Answer 7

Refers to a condition where the patient does not seem to realize that the left-hand side of the world even exists

–> only occurs with right brain damage

Question 8

How can Hemifield neglect be explained ?

Answer 8

It might arise due to lack of attention

–> as no visual problems seen

Question 9

Hemianopia/

Blindsight

Answer 9

Refers to condition where lesion to V1 on one side will result in blindness on the eye of the opposite side

BUT: when asking patients what they saw with just that eye they guessed correctly 95% of the time, even though they were sure they didn’t see anything

Question 10

Are people suffering from blindsight conscious ?

Answer 10

This is highly debatable,

as they have vision without the visual qualia that goes with seeing

–> so consciousness must be something separate

Question 11

Access consciousness

Answer 11

Refers to the availability of info for use in

a) reasoning
b) speech
c) action

Question 12

Access consciousness

Answer 12

Refers to the availability of info for use in

a) reasoning
b) speech
c) action

Question 13

Blocks take on cosciousness

Answer 13

According to him Blindsight is Access consciousness without phenomenal consciousness

Question 14

Doctrine of concordance

Answer 14

Refers to the agreement that

a) cognitive processes
b) behavior
c) phenomenal experience

are highly correlated

BUT: there can be dissociations btw the 3 as seen in certain diseases

Question 15

Anosognosia

Answer 15

Refers to a condition where the person is unaware of having it

–> part of the mind knows the fact whereas the other part doesn’t, resulting in denial

BUT: only occurs w/ damage to particular parts of the right parietal lobe

Question 16

There has been a lot of debating about whether the phenomenon of “Blindsight” really exists.

Name the 4 strongest reasons why it does not exist.

Answer 16

Blindsight is

1. just light that strayed from blind into seeing field
2. degraded normal vision
3. results from the patient being overly cautious about saying they see sth
4. depends on residual islands of cortical tissue

BUT: all of these have been disproven, thus it must be real

Question 17

Evidence for phenomenal awareness of the blind field comes from 3 separate phenomena.

Name them

Answer 17

1. Riddoch phenomenon
2. Hemianopic completion
3. After-images

Question 18

Hemianopic completion

Answer 18

Occurs when a visual stimulus is presented across both HPs and the patients are bale t complete the whole figure

–> most effective when symmetric or some regularity

Question 19

After images

Answer 19

Refers to a repression of a vivid image after the image has ceased

Question 20

There have been demonstrations of V1 playing a crucial factor in awareness.

But is it really the gatekeeper of awareness ?

Answer 20

Probably not,

but nonetheless it might play an important role since it has recurrent loops with a lot of regions

–> so neural responsiveness is affected by lesions in V1

Question 21

Super blindsight

Answer 21

After training the patients confidence in his intuition he or she should be able to talk, act upon + use info from the blind field

Question 22

Sensory substitution

Answer 22

Patients are given info to one sense to replace another

e.g.: sound replaces vision