Consciousness Flashcards
(39 cards)
What did Descartes propose about consciousness?
Dualism - it is independent of the physical world
There is something unique and important about the subjective nature of experience (my experience is unique and different to yours)
What did Shen (2019) find that contradicts Descartes view of consciousness?
AI over time can reconstruct what image is being shown to a participant based on the fMRI activity
Combines hierarchical neural representations to reconstruct perceptual and subjective images - consciousness?
(Thus NOT independent)
What was John Searles philosophical view of consciouness?
There is something special to it so you cannot just boil it down to computational rules
What evidence is there to contradict Searle’s view?
Markram (2015) reconstructed a rat’s cortical network using AI - simulate consciousness?
What evidence contradicts the theory that consciousness is unique to the subjective nature of experience?
▪️ Rats connected by electrode - one responds to what the other has seen
▪️ Conjoined twins - shared subjectivity/consciousness? (e.g., shared thalamus so can feel what each other feel)
What can we do unconsciously?
▪️ Regulate HR, breathing, temperature…
▪️ Learning? (repeated work under anaesthetic, more likely to complete sentence with that word but limited to phonetics, not semantics)
What do we need consciousness for?
Almost all complex forms of cognition
▪️ Logical operations
▪️ Cause and effect
▪️ Sequential information
▪️ Non-trivial maths
▪️ Understanding social and cultural forms of knowledge
When might consciousness IMPAIR function?
▪️ Required when learning new complex task BUT gets in the way once we’ve learned that expertise (e.g., expert golfers better when distracted)
▪️ Over-stratigisation (e.g., guess pattern of lights on, 80% on the right so best would be to always choose right but instead we superimpose patterns that don’t exist)
What does change blindness tell us about psychological factors of consciousness?
▪️ Its very limited (hard to spot obvious difference)
▪️ May relate closely to attention
What are the main similarities between consciousness and attention?
▪️ Feature binding
▪️ Predictive coding
▪️ 300ms delay following presentation
▪️ Highly selective processing (filter all information into few salient features)
▪️ Top-down control
▪️ Competition - the ones that win enter both attention and consciousness
What are the four component processes proposed to be fundamental to attention?
▪️ Working memory
▪️ Competitive selection (those most important will enter into attention)
▪️ Top-down sensitivity control
▪️ Filtering for stimuli likely to be behaviourally important (salience filters)
What neurological condition gives us really good insight into the relationship between attention and consciousness?
Hemispatial neglect
▪️ Can see but cannot attend to one side of space
▪️ Not conscious of that side of space either
What is Bor and Seth’s model for the connection between consciousness and attention?
- World
- Bottom up saliency filtering (what’s important)
- Modulated by general current state (e.g., memories, emotions, expectations, goals)
- Competitive selection - only those MOST important pass conscious threshold to reach conscious content
- All fed back by top-down control to inform general state
How limited is consciousness?
Distinguish between 3-4 items (pretty universal)
BUT can use chunking and strategies to improve this (multi-level pattern spotting unique to use)
How does chunking help learning?
We chunk data and information based on years of pattern recognition to help develop complex skills
Does consciousness aid this?
What are the two key questions relating to consciousness in the brain?
- What in the brain allows us to have the conscious experiences (CONTENT) we have when awake?
- What in the brain distinguishes the LEVELS of consciousness (e.g., awake, dreaming, deep sleep, anaesthesia, coma)?
What is the issue with brain scanning and standard images to study contents of consciousness?
Hard to distinguish conscious from unconscious experience (both would show differences based on the picture shown)
How can we overcome this issue of brain scanning and consciousness?
Use bistable stimuli - optical illusions that have two different conscious experiences e.g., old lady and young lady
Conscious perception will change every few seconds - can we capture this in the brain?
What was Logothetis’ famous monkey study?
- Trained on task - L lever for B&W radial, R lever for face, nothing for combination
- Binocular rivalry and both stimulus always presented
- One percept at a time but alternates
What did Logothetis find?
▪️ Only ~20% of V1 and V2 neurons involved in change
▪️ Nearly 90% of inferior temporal cortex - key region for consciousness?
BUT only visual/object recognition?
(later study found it in lateral PFC with different stimuli)
To summaries all studies on fMRI and changes in visual consciousness with binocular rivalry, what are the two clusters of brain areas thought to be key?
▪️ Posterior parietal cortex
▪️ Dorsolateral prefrontal cortex
(frequently coactivated network)
What network seems to be involved in changes in conscious content?
The prefrontal parietal network
(DLPFC and posterior parietal)
How can visibility studies be used to investigate conscious perception?
▪️ Look at differences in activation between visible/audible stimuli and masked stimuli
▪️ What is always activated vs what is only present when consciously perceive stimuli
▪️ Can do with fMRI or intracranial EEG
(Prefrontal parietal network irrespective of stimuli!)
What have visibility studies using intracranial EEG concluded about consciousness?
▪️ When stimuli are conscious, extra activity appears ~300ms after stimulus onset
▪️ Activity is particularly strong in high gamma range (>40Hz frequency spike)
