L11 - Volition Flashcards
What did Descartes do?
- Looked at introspection philosophy = I think therefore I am
- Thought there was an organ that allows change from spiritual to physical world
How did this become psychological?
- Thought introspection was unscientific and generalised studies from frogs to humans for anatomy = using measures like RT and accuracy= involved stimulus - sensor - brain - muscles (away from spirituality and priests)
- Donders created a broken down version of this: light - eye - detection - identification - action selection - muscles
- McLelland: does this occur in a sequence or parallel
How to record objective measures?
- RT and accuracy
- Objective measures can be recorded = feel/think things whilst doing task = can be partly captured with subjective measures
How does a perfect trial feel?
- Perception during detection phase
- Consciously thinking during identification phase
- You want to please researcher/do well on task - feeling during action selection
- All realm within subjective domain - no way of knowing objectively, so need to ask
- People have conscious perception are on task and have volition
How does an inperfect trial feel?
- When you have a slow RT and no accuracy
- Conscious perception is not there, off-task and no volition
- Sometimes finger presses button, but you do not have the feeling of making that decision
- Objective and subjective measures have a common timeline = they happen at the same time and can be measured concurrently, and correlate across trials but can be weak
What is another type of imperfect trial?
- Not on-task but has conscious perception and volition (pays attention to some not others)
- They are accurate but not fast RT
- Objective and subjective measures are often inconsistent
- Are objective and subjective domains causally related
What is Hypothesis 1?
H1: Objective states of my brain-body system influence my subjective state
How does the visual cortex (objective) cause seeing (subjective)?
1) Evidence comes from brain lesions, participants had bullet holes in the back of the brain, specifically visual system
- Measured where hole was and where visual system became blind
- Loss of neurones in the visual cortex leads to loss of conscious visual experience = same for other modalities and other functions
- Disrupt objective state = disrupt subjective state
2) Evidence comes from brain stimulation: retinal degeneration caused recent blindness in patient
- Inserted array of electric stimulators under the skull occipitally, so each sensor can be triggered
- Electric stimulation of neurones in the visual cortex leads to conscious visual experience of white spots (phosphenes)
- Was replicated in healthy participants as well
What is Hypothesis 2?
- My subjective states influence the objective states of my brain
- Through mental imagery as brain chooses to think of something = they see something
What was a study looking at mental imagery and brain activity
- Asked controls to imagine tennis or spatial navigation in their home and were in an MRI scanner
- Contrasted about when people didn’t think about anything in particular vs tennis vs your house
- Different, specific brain activity was found
- Unresponsive patient in coma can do this as well
How is visuo-spatial attention orienting an example of subjective on objective?
- If we orient our attention = visual areas = we see things better
- Ask someone in a scanner and orient their attention based on quadrants, switch attention = found evidence that brain activity changes
- When people orient their attention increased visual activity in the corresponding part of the brain and decreased it in other areas = shifting resources
Volition?
Refers to capacity for goal-directed endogenous action, shared by humans and some other animals
How to define the elements of volition?
- Internal generation: volition = not externally triggered e.g electrically shocked
- Under decisional control: Volition = not habitual/automatic
- Goal Directedness: Reasons, Values, Outcomes
- Spontaneity
- Subjective experience
Describe internal generation?
- Not governed by immediacy of sensory input or motor output
- Does not mean that action occurs out of nothing, but related to many things
- When out of nothing = unrelated to a change in brain activity
What is decisional control?
- An action is volitional to the extent that it does not occur stereotypically, routinely and automatically
- What makes an act volitional its origin in a specific decision that this action is appropriate in this current context
