Cognitive Neuroscience - Thinking and Consciousness

Question 1

What do we need for conscious experience?

Answer 1

As patients can act appropriately towards stimuli they claim they are not conscious of - does this mean consciousness plays no causal role in mental life?

Likely not - see voluntary action; however, limited success on tasks such as these (that require a forced choice) might mean the range of operations that can be achieved without consciousness is more extensive than might be considered otherwise

Question 2

How do blindsight and neglect (and prosopagnosia) allow us to study consciousness?

Answer 2

Examples of dissociations - between behaviour and experience: stimulation changes whilst experience remains constant - stimulus can be present or absent but in both instances patient can be unaware

Question 3

How do we experimentally study consciousness?

Answer 3

Happens in lots of typical experiments and by varying stimulation, we can induce different behaviours or conscious experiences and see dissociations between the three:

Recognition memory - hits/misses on a old/new word task, change in stimulation = same behaviour, same conscious experience

Nekker cube - change in conscious experience = same stimulus (and behaviour)

Implicit learning - (Lewicki et al, 1987) - change in behaviour = same conscious experience and same stimulus

Question 4

How does the brain support consciousness?

like any answer could fit on the back of a flashcard

Answer 4

Possibilities:

Certain parts support consciousness, others don’t

Activity in regions must exceed some threshold for ‘consciousness’ to occur

The nature of the interaction between brain regions gives rise to consciousness; activity in a specific region might give rise to consciousness when engaged to another specific region and not others

Some properties of neural activity (temporality), determine if consciousness is association with some cognitive operations and not others

Combination of above or other….

Fuck knows basically.

Question 5

How should we attempt to investigate the problem of consciousness?

Answer 5

Accept the problem is intractable:

1) because it is not a property emerging from neural tissue (AS COGNITIVE SCIENTISTS, THIS OPTION IS NOT FEASIBLE)
2) because although the brain does support consciousness, the way in which it does so is too complex to understand/explain (A MORE SCIENTIFIC BUT STILL DEFEATIST ATTITUDE)

Alternatively, consider current stae of knowledge - ask what kinds of questions it is reasonable to frame currently

Question 6

What is blindsight and how does it work?

Answer 6

Some patients can respond to stimuli in the ‘blind’ part of their visual field under certain conditions, even though they do not ‘see’ anything

Occurs because there are multiple routes to ‘seeing’ in the brain ie there is an LGN-MT projection that bypasses V1 + maybe more

Not the same as normal seeing - impaired shape/colour discrimination ie patient GY - could unconsciously detect rapidly moving stimuli at low luminance but not if speed slowed or luminance increased (V5 activation without V1)

Question 7

What does fmri research tell us about brain activation in decision making and the Wason task in frontal lobe lesion patients?

Answer 7

General decision making:
Familiar easy tasks - left hemisphere fronto temporal system
Unfamiliar arbitrary rule tasks - bilateral parietal (L>R) + some dorsal PFC

Wason task:
Concrete permission>abstract permission>arbitrary rule Perrmission conditions = asymmetrical frontal lobe involvement depending on familiar knowledge requirement (controls)

L frontal lobe lesions = inability to use familiar social information, overall lower performance = no improvements on concrete condition; arbitrary rule condition - parietal involvement>PFC involvement = slightly better performance;