Chapter 4: The Mind and Consciousness
- Locked in syndrome: occurs when part of brain stem gets damaged. Awake and alert but cannot
communicate – Jean-Dominique Bauby. Brain imaging allows researchers to see that similar
regions of brain activated in coma patient and in healthy patients.
How is conscious mind experienced?
- Our brains active during sleep, even though we are not conscious
- Consciousness: moment-by-moment subjective experiences, such as reflecting on current
thoughts or paying attention to immediate surroundings. It refers to awareness and
experiences
- Scientists study 2 components of consciousness:
o Contents of consciousness: things we are aware of
o Level of consciousness: coma, sleep, wakefulness
- Also focus on things humans do consciously – speaking, and unconsciously: scratching
- Activity of neurons produces contents of consciousness. Each content has diff brain activity
Consciousness is a subjective experience
- Cannot know if we all experience world in exactly same way
- Quilia: word to describe our subjective experiences – such as perception. i.e. does color red
look the same to everyone who has normal vision? When people say “I know how you feel” do
they really?
- Scientists can look at brain activity and determine which object you are looking at. brain
imaging
- Frank Tong (1998): studied relationship b/w consciousness and neural responses in brain.
Showed diff types of sensory info are processed by diff brain regions: particular type of neural
activity determines particular type of awareness
- Motor control: placed in monkeys who were able to control joystick by thoughts. In future
potentially help paralyzed people
There are variations in conscious experience
- Limit to consciousness. Cannot multitask a lot at once
- Automatic tasks: able to do certain things like driving, walking w/out thinking about it
- Consciousness and coma
- Persistent vegetative state: when in coma for longer than a month. Brain can process info in
this state, but cannot respond physically. The longer the person in this state, the less likely they
are to recover
- Minimally conscious state: between vegetative and full consciousness state. Able to make
some movements such as follow object w/ eyes and try to communicate.
Splitting the brain splits conscious mind
- Used to treat epilepsy by cutting through brain (corpus callosum) to isolate site of seizure
initiation. Therefore, seizure that begins at site will less likely spread through cortext = minimal
damage. After, called split brain
- Visual input: images from left side go to brains right hem and images from right side go to left
hem. Left hem: better w/ language. Right hem: better with spatial relationships
- Split brain experiment: cannot verbalize what is seen, but can pick up correct object. Splitting
brain produces two half brains, each w/ own perceptions, thoughts, and consciousness
- The interpreter: a left hem process that attempts to make sense of events.
o Sometimes when patients asked to do something, patient does not know why they are
doing it, because left hem mute. They cannot make connections between 2 hems.
Unconscious Processing Influences Behaviour
- We are aware of some mental processes and not aware of others
- Subliminal perception: info processed w/out conscious awareness. It refers to stimuli that get
processed by sensory systems but b/c of their short durations, they do not reach consciousness.
- Frudian slip: mistake in which an unconscious thought is suddenly expressed at an inappropriate
time
- Much of our behaviours occurs w/out awareness or intention