TASK 1 - AWARENESS

Question 1

consciousness

Answer 1

= probed through the subject’s report of his or her own mental states

• not directly and straightforwardly observable
• psychological attributes of conscious processing:
  1. active maintenance of mental representations
  2. strategical processing
  3. spontaneous intentional behaviour

Question 2

third-person data

Answer 2

= brain processes, behaviour, environmental interaction
- EEG, brain imaging, single cells studies and so on
x stem from technological + ethical limitations rather than conceptual barriers

Question 3

first-person data

Answer 3

= subjective conscious experience (= central data we want science to explain)

• can’t wholly be expressed in terms of first-person data
• introspection, phenomenologists…
• serious obstacles BUT they should not provide barriers to initial development of methods

Question 4

first-person data

- obstacles

Answer 4

x all have serious limitations and none have been integrated into contemporary science (e.g. lack of incorrigible access to experience)

(1) lack of access to our experience
(2) introspecting an experience changes the experience
(3) impossibility of accessing all our experience at once
(4) grand illusions

Question 5

first-person data

- formalism

Answer 5

= simple language that is imprecise + relies on perspective (can the content of experience even be captured in language?)

• obstacles: (greater) whether the content of experience can be captured wholly in language –> easier to capture structural (e.g. structure of visual field) aspects than non-structural (e.g. sensation of a colour) aspects of experience
• even in the non-structural we can find an underlying structure (e.g. decomposing colour experiences into brightness, saturation, and hue)
• -> develop a theory of proto qualia

Question 6

formalism

- proto qualia

Answer 6

= qualia we experience are systematically built up from simple building blocks which are present across many experiences

Question 7

science of consciousness

Answer 7

= relating third-person to first-person data

• come up with broad connecting principles: certain experiences go along with certain processes in the brain/ information processing
• be able to formulate simple + universal laws underlying these connecting principles: “fundamental theory” of consciousness
• -> necessary to develop more sophisticated methodologies & formalisms (especially with respect to first-person data)

Question 8

neural correlate of consciousness

Answer 8

= NCC = neural system/ system primarily associated with conscious experience

• cannot be measured directly
• need to use principle of interpretation (=pre-experimental bridging principles) to determine whether someone is conscious of something

Question 9

NCC

- pre-experimental bridging principles

Answer 9

= principles of interpretation = by which we interpret physical systems to judge the presence of consciousness

• identify (1) whether or not systems are conscious now + (2) which information they are conscious of, and which they are not
• principles by which we make inferences from facts about processing –> to facts about consciousness
• conceptually prior to experiment
• philosophical reasoning: we have to make leap between (1) conceptual judgements about what counts as a conscious process and (2) information from our first-person perspective of our own consciousness
• -> need to pay careful attention to the reasoning involved

Question 10

bridging principles

1. principle of verbal report

Answer 10

= when information is directly available for verbal reported, it is conscious
- only subjects that have language

Question 11

bridging principles

2. principle of global control

Answer 11

= when information is directly available for an arbitrary response OR for global control (any motor modality) in a cognitive system, then it is conscious (first-person evidence)

• primary criterion for consciousness
• applicable when language is not present

Question 12

NCC

- rational reconstruction

Answer 12

• with these principles we can produce rational reconstructions of the search for the NCC
  = maybe things do not work exactly like this in practice, but the rational underpinnings of the procedure have something like this form
  1) consciousness global availability (bridging principle)
  2) global availability neural process N (empirical work)
  3) consciousness neural process N (conclusion)
  –> instead of measuring consciousness directly, we detect the functional property (e.g. global availability) –> when present = correlated with a specific neural process
  –> combining the pre-empirical premise with the empirical result –> get to the conclusion that this neural process is a candidate for the NCC

Question 13

NCC
- consequences of rational reconstruction/for bridging principles
1.

Answer 13

• NCC MUST BE a mechanism that subserves global availability in the brain (only other option would be that it’s a symptom of global availability, would be dissociable)
• consciousness can be present even when the neural process in question is not

Question 14

NCC
- consequences of rational reconstruction/for bridging principles
2.

Answer 14

• neural process associated with consciousness will do 2 things:
  1. explain global availability (= how info is made available for global control in the brain)
  2. isolate the processes that underlie consciousness itself (if bridging principle is granted)
• can never FULLY explain consciousness, it can only isolate the basis for it

Question 15

NCC
- consequences of rational reconstruction/for bridging principles
3.

Answer 15

• likely that there will be many NCCs:
  (1) because there will be many mechanisms of global availability (e.g. mechanisms in different modalities: visual availability, auditory availability, etc.)
  (2) many mechanisms at different stages in processing whereby information is made globally available (early/late)
• can co-exist because they’re compatible in one way

Question 16

NCC
- consequences of rational reconstruction/for bridging principles
4.

Answer 16

• there is a possibility for a consciousness module (= functionally localisable, internally integrated area through which all global availability runs)
• resembles Baars’ global workspace: functional are responsible for integrating information and disseminating it to multiple non-conscious specialised processes
• BUT, just as likely that we will find multiple independent mechanisms of global availability, scattered around without mutual integration

Question 17

NCC
- consequences of rational reconstruction/for bridging principles
5.

Answer 17

• if a given area in V1 projects to the PFC it may well be a mechanism of direct availability (PFC is associated with control processes)
• if it doesn’t, it is less likely to be such a mechanism (might at best be indirectly associated)

Question 18

NCC
- consequences of rational reconstruction/for bridging principles
6.

Answer 18

• we should not follow reasoning that “if NCC is discovered, then the NCC itself will be used as a consciousness meter” –> we do not have a way of establishing an NCC as an independent test for consciousness
• NCC suggestions are only relevant because of their role in satisfying bridging principles (global availability, verbal report) –> it is not clear that anything follows when the functional criterion is thrown away
• -> there is no way of definitely establishing a given NCC as an independent test for consciousness (it is relevant only in combination with the bridging principles)

Question 19

vegetative state

Answer 19

= patients who emerge from coma appear to be awake but show no signs of awareness

• no reproducible evidence for purposeful behaviour in response to external stimulation
• found islands of preserved brain function (exist in small percentage of patients)

Question 20

awareness in vegetative state

• owen
  (1) study 1

Answer 20

• measure neural responses to spoken sentences, compare with responses to acoustically matched noise sequences
• activity matched that of controls
  A. bilateral activation in middle + superior temporal gyri
  B. left inferior frontal region (especially in response to sentences that contained ambiguities)
  –> sentences containing ambiguous words produced an additional significant response (reflecting speech comprehension)
• BUT not evidence for conscious awareness: speech perception and semantic processing can happen in the absence of conscious awareness

Question 21

awareness in vegetative state

• owen
  (2) study 2

Answer 21

• spoken instructions to perform mental imagery (play tennis + walk through own house)
• activity was indistinguishable from that of healthy controls
  A. imagining playing a game of tennis: supplementary motor area (SMA)
  B. imagining visiting all rooms in the house: para-hippocampal gyrus, posterior parietal cortex, and lateral premotor cortex
  –> represents clear act of intention = confirms conscious awareness of herself + surroundings

Question 22

awareness in vegetative state

• owen
  (3) results

Answer 22

• patient retained the ability to understand spoken commands and to respond to them through her brain activity, rather than through speech or movement
• some non-communicative, vegetative, minimally conscious patients may be able to use available cognitive capacities to communicate their thoughts to those around by modulating their own neural activity

Question 23

awareness in vegetative state

- naccache

Answer 23

• we should not generalise from a single patient (who suffered few cerebral lesions) to most other vegetative patients (who typically have massive structural brain lesions)
• current behavioural and neuro-imaging evidence suggests that conscious processing is abolished during a vegetative state –> do not report mental states, do not spontaneously engage in intentional actions (aspects of consciousness)
• long-range neural integration observed during conscious processing is lacking (only found residual local and specific brain activation patterns)
• owen: study paves way for future functional brain-imaging studies

Question 24

awareness in vegetative state

- burton

Answer 24

• can see activation but not the images transition from the unconscious to the conscious perception
• can’t say anything until we know if a choice is truly deliberate or just the unconscious activation of neural circuitry
• preservation of isolated neural networks shouldn’t be construed as representing conscious awareness
• -> there is activity but we don’t know whether it can be attributed to consciousness
• -> need to understand what neural states correspond to specific conscious experiences –> until then fMRI pronouncements only speculations
• -> fMRI accuracy, reliability, and interpretations remain debatable
• owen: possibly her injury destroyed her ability to make unconscious thoughts conscious BUT left her auditory pathways and subconscious processing mechanisms sufficiently intact to hear and respond to the researchers’ questions (not conscious intention and choice)

Question 25

awareness in vegetative state | - monti

Answer 25

- 40% misdiagnosis: new methods - main goals of clinical assessment: 1) capacity for a purposeful response to a stimulation, however inconsistent - suggests at least partial awareness (distinguishes minimally conscious from vegetative state) - behaviour often ambiguous and inconsistent = difficult to distinguish between reflexive and voluntary behaviour 2) transform any available response into form of reproducible communication, however rudimentary - consistent communication defines the upper boundary of a minimally conscious state

Question 26

minimally conscious state

Answer 26

= show inconsistent but reproducible signs of awareness | - including ability to follow commands, but remain unable to communicate interactively

Question 27

monti | - imagery task

Answer 27

- aim: what proportion can modulate their fMRI responses - access patient’s ability to generate wilful BOLD responses during two established mental-imagery tasks - 54 patients

Question 28

monti | - imagery task results

Answer 28

- 5 were able to wilfully modulate their brain activity - -> 3 showed sign of awareness with additional bedside testing - -> 2 showed no remaining voluntary behaviour 1) 5 patients: motor imagery showed considerable activation of SMA 2) 4/5 patients: spatial imagery showed activation in parahippocampal gyrus 3) time course of activity within two regions of interest was associated with delivery of verbal cues (sustained for 30s) - small portion of patients in vegetative or minimally conscious state have brain activation reflecting awareness and cognition - careful clinical examination could result in reclassification of some of the patients

Question 29

monti | - communication task

Answer 29

- aim: can they communicate yes/no responses (one type of imagery (motor vs. spatial) as affirmative, one as negative answer) - develop and validate a method that allows patients to functionally communicate yes-or-no responses - -> by modulating their own brain activity, without training + without the need for any motor response 1. patient who had reliable responses during two imagery tasks in the fMRI 2. patient asked to respond to yes-or-no autobiographical questions by thinking of one type of imagery (motor or spatial) for an affirmative answer and the other for a negative answer

Question 30

monti | - communication task results

Answer 30

- one patient was able to use technique to answer yes or no questions during fMRI - -> for 5/6 of the questions: activity was within bounds of normal variability - -> pattern produced always matched the factually correct answer - -> BUT impossible to establish communication at bedside with the patient - approach could be used in future to address important clinical questions: feeling pain + determine whether analgesic agents should be administered - if developed further: express thoughts, control environment --> increase quality of life

Question 31

monti | - limitations

Answer 31

- impossible to determine whether, in patients who showed no significant fMRI changes, negative findings were the result of low sensitivity of method, or a genuine reflection of the patients’ limited cognitive abilities - some patients could have been unconscious (permanently or transiently) during scanning - task could have exceeded the residual cognitive capabilities of those in a minimally conscious state