What are 6 facts about consciousness?
- people can be conscious even when they appear not to be
- all conscious experience is associated with brain activity
- variations in consciousness occur naturally
- consciousness can be manipulated
- consciousness varies from person to person
- consciousness does not need to be linked to cognition
inverted spectrum argument
we cannot know if two people experience the world in exactly the same way
What are three different levels of conscious experience?
- sleep/wake cycle
- automatic tasks i.e. driving, walking
- controlled processing
- helps us to perform in a complex or novel situation
- hyper focusing on specific tasks
what are 4 example of "extreme states"?
- "locked in"
- persistant vegetative state
- minimally conscious state
- no damage to consciousness
- can communicate with eyes
- ex. Erik Ramsey or Stephen Hawkings
- unconscious for more than 6 hours
- patient does not respond to pain, light or sound
- no sleep/wake cycle
- mechanism for humans to cope with damage
persistant vegetative state (2)
- may be awake but no awareness
- has signs of functioning related to wakefulness but no processing at a higher level
minimally conscious state (1)
deliberate movement and communication are possible
What actions are possible in the best case scenario for a minimally conscious patient?
they can reach fro objects, hold objects correctly, and move eyes on command
What proves consciousness in a coma?
when asked to visualize playing tennis, the brain areas activated by coma patients is similar to the brain areas activated by awake patients
How can brian activity be measured as it relates to consciousness?
through brain imaging
Tong et al experiment description
participants are shown images of faces superimposed on houses and asked if they saw a house or a face.
Tong et al experiment results
Increase in blood activity in fusiform face area when participants reported seeing a face, and increase in blood activity in temporal cortex region when participants report seeing a house.
In which hemisphere is language located and how does that effect the ability of split brain patients to complete specific tasks?
- Language is located in the Left hemisphere
- split brain patients cannot report an object presented to their left visual field although they wold be able to choose the object with their left hand
In which hemisphere are spatial tasks primarily processed and and how does that effect the ability of split brain patients to complete specific tasks?
- Spatial tasks are located in the R brain
- Split brain patients cannot arrange blocks to fit a specific shape with their right hand, they must do so with their left hand
Explain the concept of an interpreter between the hemispheres
The Left hemisphere attempts to make sense of the world, even when it doesn't particularly understand, as is the case in split-brain patients.
What is the role of the Left hemisphere and the Right hemisphere?
- Left: imposes narrative structure, tries to make sense of the world
- Right: simply experiences world
What are the three hypotheses about consciousness?
- 1. consciousness as the privileged role of particular brain systems
- 2. consciousness as a state of integration among distinct brain systems
- 3. consciousness is a graded property of neural information processing
Explain how consciousness is the privileged role of particular brain systems
- processing in some but not all areas gives rise to consciousness
- consciousness is distributed among many brain systems
- damage to primary visual cortex causes cortical blindness
- patients are subconsciously aware of surroundings
What role does the lateral geniculate nucleus play in blindsight?
Gives information about location of stimuli without conscious awareness
How does blindsight prove that consciousness is the privileged role of particular brain systems?
Both lateral geniculate nucleus and the visual cortex do visual processing. Only visual cortex gives rise to conscious experience
Explain consciousness as a state of integration among distinct brain systems
- In the visual cortex, color and form are processed separately
- conscious percept only arises when these two elements are bound together
Explain how consciousness is a graded property of neural information processing
- information must be processed to a high degree to be conscious
- ex. subliminal priming, masking, brain damage
Which one of the three hypotheses about consciousness is correct?
- Trick question!
- They are not mutually exclusive and could all be correct
What are the 3 functions of consciousness?
- 1. helps us to perform complex actions with input from several brain regions
- 2. helps us connect w. one another by sharing thoughts and feelings
- 3. required for complex thinking and understanding
global workspace model
- consciousness arises by output of active brian circuits
- you cannot be aware of a brain deficit if that brain area is no longer active
What is the condition of heminegelct?
when patients are unaware of a damaged visual capacity
How does the left brain's role influence its memories as compared to those of the right brain?
- The left as an interpreter tends to "compress" experiences into comprehensible story and remember details based on the gist of the story.
- The right brain has a less distorted by narrative interpretation memory of story
How does the human brian function differently from a rat's in an experiment where pressing a red button (as opposed to a green button) randomly presents a reward 70% of the time?
Rats will press that button 100% of the time and receive the maximum amount of reward.
Humans will press the button about 70% of the time and only receive about 58% of reward.
This is because humans' left brain always searches for patterns even when they don't exist.
processing of information by sensory systems without conscious awareness
Examples of subliminal perception
- advertisements utilize subliminal perception
- Freudian slip
- people presented with words about the elderly walked slower after the experiment
How does the unconscious play a role in decision making?
Unconscious thought (like deciding after working on a hard problem or sleeping on it) yields best results when making a difficult decision