Task 7- Consciousness Flashcards
What is the doctrine of concordance?
Cognitive processes (thought), behaviour and phenomenal experience are highly correlated --> “there exists a close and general, even if not perfect, agreement between what people know, how they behave, and what they experience"
When does the doctrine of concordance smth not apply?
However, in some cases there can be dissociations btw the three
- e.g. blindsight: dissociation btw subjective and objective measures
- -> does not apply actually
What are characteristics of Korsakoff’s Syndrome?
- What are the causes for it?
- What is destroyed?
- Toxic effects of alcohol and thiamine deficiency
- Destruction of mammillary bodies, dorso-medial nucleus of thalamus and diffuse damage to frontal lobes
Which kind of amnesias do people with Korsakoff’s Syndrome have?
-What is still intact?
- Anterograde amnesia: inability to form new LTM while STM stays intact
- Retrograde amnesia
- -> Classical conditioning and procedural learning unimpaired
Are Amnesics conscious?
- Yes, they are awake, responsive, able to converse, laugh and show emotion
- BUT self is trapped in the past and unrelated to events and people of the present
- Lost interaction btw current and stored info (according to Weiskrantz this makes the commentary that underlies consciousness possible)
- Create no memory of a continuous self
Which different types of neglect are there?
- Anosognosia
- Anton’s Syndrome
- Unilateral Neglect
What are characteristics of anosognosia?
- condition in which a person with a disability is unaware of having it (deficit of self-awareness)
- part of their mind seems to know the facts while another part does not
- only occurs with damage to particular parts of the right parietal lobe, not with damage to the left
What are characteristics of Anton’s Syndrome?
- blind but insist that they can see (confabulate if they bump into things and stuff)
- when parts of the visual system gone -> no neurons calling for info that could notice that sth is missing
- -> might’ve lost the idea of “seeing” rather than losing ability for sight
What are characteristics of Unilateral Neglect?
- Neglect left hemifield
- only with brain damage on the right side
- Visual responsiveness can still be detected in neglected areas
- -> Emotional stimuli can influence attention
- -> Stimuli that are not consciously seen prime later responses
- Stimuli that are not consciously affect behaviour: subject may not know it, but some part of the brain does
- -> House on fire: say the 2 look identical but prefer to live in the one that is not on fire
- -> Partly explained as a deficit of attention
Which characteristics of blindisight are there?
- effectively blind due to V1 damage on one or both sides
- other non-cortical visual pathways remain intact (motion)
- get input but do not reach V1 -> have guesses
What are 4 reasons against the existence of blinsight?
- might not actually exist –> Light might’ve strayed from blind into seeing field (disproven)
- may not be more than degraded normal vision -> must match severely restricted visual function and severely degenerated qualia
–> Disproven: respond accurately while claiming no awareness at all (accuracy doesn’t match confidence) - Blindseers are just overly cautious about saying they see sth –> isn’t the sensitivity that is affected but their response criterion is raised (disproven)
- Blindsight might depend on residual islands of cortical tissue
–> Disproven: no activity at all in G.Y.’s V1, so must depend on other structures
–> There are a bunch of parallel pathways from the eye to different parts of the brain
–> LGN: V1 damages
–> Eye: superior colliculus -> cortical and subcortical areas still intact (in blindsight)
What are implications for the interpretation of blindsight that blindseers have vision without consciousness?
- Partial zombie who can “see” functionally but has none of the visual qualia that go with normal seeing
- SO, consciousness is sth separate from ordinary processes of vision -> qualia exists and functionalism is wrong
- Implies that we can find a place in the brain where qualia (phenomenal consciousness) is produced and that qualia would happen in V1 while the rest of vision goes on elsewhere
- Based on findings that the surviving cortex is unable to generate qualia
–> However, there have been reports of patients with V1 damage that seem to be aware of some events in the blind field
What are implications for the interpretation of blindsight that blindseers have still consciousness?
- Super blindsight
- Sensory substitution
- Super-blindsight: after training of confidence in intuition, people should be able to talk about, act upon and use information from the blind field just as well as from seeing field (does not exist!)
- -> Functionalists: it implies consciousness
- -> Believers of qualia: no, because function and qualia are two separate things
- -> Functionalists: it implies consciousness
- Super-blindsight goes beyond actual blindsight: they cannot actually recognise forms/ identify familiar objects
- Sensory substitution – people are given info to one sense to replace another (e.g. sound replaces vision)
- -> Suggests that consciousness comes along with increasing function, rather than being sth separate from it
What does Block think about blindsight?
-Block: neither access- nor phenomenal consciousness
-> Patients deny having phenomenal experiences
-> Only access they have comes from hearing their own voice when making guesses
What does Milner and Goodale think about blindsight?
- Milner and Goodale: blindsight is only paradoxical if vision is seen as a unitary process
- There is no single visual representation -> heaps of semi-independent structures which can give rise to different experiences
- Ventral stream -> perception
- Dorsal stream -> visuomotor control
