L2 - Grand Theories of Consciousness Flashcards
What does the easy problem and hard problem refer to in consciousness?
Easy - the difference between total unconsciousness vs anything more than that
Hard - The quality of the experience of colours, sounds and feelings (Qualia)
What is Binocular Rivalry
When you are shown 2 different images simultaneously, you will only be able to experience one image at a time, for a few seconds then the next
What is Backward Masking
When a masking image is displayed after presentation of the target simuli.
The greater the delay, the more likely the target will make it through to consciousness
What is the Neural Correlates of Consciousness?
NCC
The minimal set of neuronal events that give rise to conscious percept
It’s probably that at any moment, some active processesin your head correlate with consciousness, while other’s dont - what’s the difference between them
What are the grand theories of Consciousness?
- Sparse Coding
- Global Workspace
- Recurrent Processing
- Integrated information
What does the theory of sparse coding suggest?
Suggests that a relatively small collection of individual neurons (1000s) will be selective for a specific “concept”
EG: Grandmother Neurons
conscious experience of your grandmother requires neurons in your brain coding “grandmother” to fire.
This is regardless of orientation, size, location etc, and will fire every time grandmother is perceived, smelt or thought of.
- Jennifer Aniston and Bill Clinton neurons have been found using bino rivaly. Fires everytime they see them, regardless of what the picture is..
What does the theory of Global Workspace suggest?
- Theatre metaphor of mental functioning
- consciousness resembles a bright spot of the stage of WORKING MEMORY, directed there by a spotlight of attention
- the rest of the theatre is dark and unconscious.
- BTS is contextual systems which shape conscious contents w/o ever becoming conscious.
- The act of transmitting these data from the brain’s working memory buffers to the functional modules is what gives rise to consciousness
Findings:
- different areas of the brain were activated when conscious awareness of a stimuli was achieved through backward masking.
- the weaker the mask (longer delay) the better chance of it reaching consciousness.
- same pattern was found for conscious awareness of words and sounds.
THEREFORE the information was TRANSMITTED from working memory to FUNCTIONAL MODULES giving rise to consciousness
What does the theory of Recurrent Processing suggest?
- Consciousness requires recurrent processing!
- Awareness requires feed-back sweep.
- consciousness is maintained as long as the re-entrant loops are maintained.
- eg. to be conscious of a visual stimulus, it needs to reach the visual cortices and then sweep forward to the frontal areas
What does the theory of Integrated Information suggest?
consciousness = integrated information (phi)
The greater the number of mutually exclusive possible states a system can cold, the more conscious it is
any system w/ integrated information is conscious
our experience is INTEGRATED - cannot experience the components seperately - eg, w/o colour
our experience is INFORMATIVE - it’s specific and distinct from alternative experiences.
also suggests that the gut and cerebellum are not conscious, as the neurons are not connected to each other. However, computers and the universe may be
What are some problems/limitations of the IIT?
Integrated information theory presents the gut to not have consciousness - however it says that any system with integrated information will be conscious - so then really the gut has thousands of micro-conscious units?!?!!
where our brain does not have access to the gut consciousness.
IIT also does not take into consideration relevant time scales. neuron activity is always changing - size of network always changing. eg in REM sleep - less integrated
What is some evidence of consciousness?
- Studies found activating parietal and frontal cortex areas correlated with changes in visual awareness.
- Other areas were activated regardless of whether info was experienced consciously.
How do all the theories fit together?
- Sparse coding requires a network of specific cells to fire for consciousness but doesnt specify where they have to be .. so POTENTIALLY consistent with global workspace or IIT.
- Data has also shown clear involvement of distributed frontal brain regions consistent with IIT, Global work space and maybe even sparse coding - if sase network is distributed widely!
