Problem 1 Flashcards
Third person data
Refer to
- brain processes
- behavior
- environmental interaction
which is measured by means of EEG, brain imaging etc
First person data
Refers to the subjective conscious experience of things
–> the central data we want science to explain
BUT: as soon as one tries to verbalize ones experience or defers from present moment this turns into 3rd person data
Formalism
Refers to simple language that is imprecise + relies an individuals perspective
–> used to collect 1st person data but not really accurate
BUT: there are attempts to develop a more structures form
What is the science of consciousness all about ?
About relating first person data to third person data
–> explaining subjective experiences, but can’t be expressed only by 3rd person data, even though there might be a strong connection
Neuro-correlates of consciousness (NCC)
Refers to the neural system that is primarily associated with conscious experience
–> cannot be measured directly
Pre-experimental bridging principles
Refer to the criteria that must be fulfilled to say that
- someone is conscious
- what they are conscious of
–> we thus interpret physical systems to judge the presence of consciousness
Principle of verbal report
Suggests that when something is verbally reported, one is conscious
Principle of availability for global control
Suggests that if info is available for response in many motor modalities, one is conscious
–> 1st person evidence
e.g.: decision making, awareness of own behavior
Rational reconstructions
Refers to sth that is produced when searching for NCCs, by using the principles
After rational reconstruction, 6 consequences may follow.
Name them.
1. Characterization of the neural correlates of consciousness
2. Explanation of global availability (GA)
- if we know about the relevant neural processes, we’ll know how info is made available for global control in the brain
3. There are many neural correlates of consciousness
- because there are many mechanisms of GA
4. Consciousness model
- which would be functionally localizable
5. NC of visual consciousness
- finding out whether they are in V1, which depends on which visual area is most directly implicated in GA
6. Theory of consciousness due to NCC
- NCC is discovered
Vegetative state
Being awake from coma but showing no signs of awareness
–> diagnosis depends on the evidence of behavior in response to external stimuli
Name the 4 attributes of conscious processing. (Naccache)
- Reporting
- Active maintenance of mental representations
- Strategical processing
- Spontaneous intentional behavior
–> without these abilities, one is not conscious
In which way is an fMRI like the photograph of a house ?
(Burton)
It can show which rooms are lighted, even the amount of electricity that is used but not what is going on or if there is anyone at home + aware off the light
Fundamental theory of consciousness
Suggests that we might be able to come up with broad connection principles which may lead to a universal law that underlies consciousness
–> for this we need good methodologies for collecting data
How well developed are the methodologies for collecting first vs third person data ?
1. 3rd person data
- well developed
ex. : EEG etc
2. 1st person data
-
not well developed
ex. : introspection
What are the most difficult obstacles in developing 1st person methodologies ?
- Lack of incorrigible access to our experiences
- Introspecting an experience changes it
- It is impossible to access all our experiences at once
- Possibility of “grant illusions”
What are the most difficult obstacles of 1st person formalisms ?
Uncertainty if
- the content of an experience can be wholly captured in language
- a description can be meaningful, when a person did not have a certain experience
Is it possible to collect 1st person data about emotional experience ?
No, not really as
- people use introspection
* unreliable - emotions are especially inexpressible, if one hasn’t experienced the emotion before
- emotions vary on dimensions
* duration, intensity, affect, etc
Why is it said that we “take a leap into the epistemological unknown” when relaying on the bridging principles ?
Because, as soon as we draw a conclusion about consciousness, we have gone beyond the information given
What are the bridging principles based on ?
- Conceptual judgments about what counts as a conscious process
- Info taken from our 1st person perspective on consciousness
How does one produce a rational reconstruction ?
- Using a bridging principle that one finds plausible
- Doing empirical research
* when a functional property is present, it should be correlated w/ a specific neural process - Combining the pre-empirical premise + empirical result to conclude whether this certain neural process is a NCC candidate
In Owens experiment, the patient was presented with
a) spoken sentences b) acoustically matched noise sequences
to discover wether an fMRI can detect conscious awareness in the patient who’s is assumed to be vegetative.
What did the results yield ?
Speech-specific activity in the middle + superior temporal gyri in both hemispheres
–> similar to response in healthy people
In Owens experiment the patient was also presented with ambiguous words to discover whether an fMRI can detect conscious awareness in the patient who’s is assumed to be vegetative.
What did the results yield ?
Response in left interior frontal region
–> similar to the response in healthy people
Does an appropriate neural response mean that the person is consciously aware and not vegetative then ?
If not, how can one discover if they are really consciously aware ?
- No, some aspects of cognition can go on in the absence of awareness
- The patients were given spoken instructions to perform mental imagery tasks
–> these neural responses were equal to the ones served in healthy individuals
Naccache diasagreed with Owens notion that his vegetative patient was actually conscious.
Why is that ?
According to him the patient should then be able to engage in intentional motor acts, given that she didn’t suffer from any structural lesions of the motor pathways
–> we cannot determine whether a person is conscious solely on the basis of a question-brain activation method
Burton also disagreed with Owens notion that the vegetive patient was actually conscious.
Why is that ?
According to him, it is unclear whether fMRI activity really responds or corresponds to consciousness, and can thus confirm consciousness
–> because, when judging a patients degree of awareness, it is important to distinguish between
a) choices that can only be made conscious
b) choices that occur outside of consciousness
Minimally conscious state
Refers to a state where a patient shows inconsistent signs of awareness, but remain unable to communicate interactively
What are the goals of clinically assessing minimally conscious state patients ?
- Determining whether the patient can purposefully respond to stimulation
- Harnessing + nurturing any available response through intervention
The disorders of consciousness are misdiagnosed in 40% of all cases. To avoid this Monti performed a study.
What was the aim of Montis study on patients in minimally conscious states ?
- Determining which proportion of the patients could modulate their fMRI response
- Developing a method that allows such patients to functionally communicate yes-or-no responses by modulating their own brain activity
What kind of Imagery tasks did Monti use on his patients ?
Name + describe them.
All participants were asked to perform two imagery tasks + alternate 30 sec of imagery w/ 30 sec of rest
1. Motor imagery task
- imagine standing still on a tennis court and to swing an arm to hit the ball
2. Spatial imagery task
- imagine navigating the streets of a familial city
=> Each scan included 5 rest-imagery cycles
Monti also used a communication task on his patients. Describe it.
Subjects underwent fMRI during which they attempted to answer questions by modulating their brain activity
a) Motor imagery = yes
b) Spatial imagery = no
–> cues were delivered once at the beginning of each period
What did the results of the imagery vs communication tasks yield ?
- Motor imagery activates SMA; spatial imagery activates parrahippocampal gyrus
* 5 patients could willfully modulate their brain activity - All questions where answered with 100% accuracy in the communication task
