Lecture 9 - Brainimaging Technologies Flashcards
What are the three aspects of brain and mind theory?
Mentalism, Dualism, and Materialism
What is Mentalism?
Behaviour is solely governed by the mind while the brain is irrelevant
What is Dualism?
Both mind and brain control behaviour
What is materialism?
Brian supports and governs mind and behaviour. All the mental states and behaviours are materialistically explainable
What do neuroimaging/ Brainimaging technologies do?
They look into the brain by turning neural systems into an image
What are the things neuroimaging/ brainimaging technologies look at? (6 things)
- Morphology/ Structure
- Anatomical network structure
- Functional network structure
- Functional association
- Dynamic activities (change with time)
- Event-related brain response
What is morphology/ structure?
The gross pattern that can be seen with our bare eyes (e.g. identifying shrieked brain due to Alzheimer’s disease)
What is anatomical network structure?
The pattern of neural tract connecting different places in the brain, which is reviewed by DTI
What is functional network structure?
An abstract and non-physical kind of connection that can only be inferred and that explains the function
What is Functional Association?
want to know the brain is associated with which function
What is dynamic activities (change with time)?
To extract information from the dynamic patterns in brain as brain is not static and constantly changes
What is Event-related brain response?
To study brain responses to a certain stimuli/ certain activity
How can you test the event-repeated brain response?
Present some stimuli to put information to the participants’ brain and then measure the ongoing activity and evoke response activity (a specific brain response to a specific stimulus to study the characteristics of brain responses to a certain stimuli)
Why we need neuroimaging?
It has been confirmed that the brain is related to some certain variables and is measurable
What variables are found to be related to brain activity? (7 variables)
- Cognitive ability
- Mental states (the overall state of cognitive system)
- Functional processes
- Emotional activity
- Subjective feelings
- Pathological states (malfunctioning in some parts)
- Development/ aging-related variations
What is invasive in brainimaging technologies?
A little harmful because it puts things inside your body
What is non-invasive in brainimaging technologies?
There is nothing penetrating your body (no technologies put in the body)
What is the measurement of MRI?
Hydrogen behaviour
Is MRI invasive/ non-invasive?
Non-invasive
What is MRI
MRI uses a magnetic field, radio frequency pulses and a computer to produce detailed 2D images pictures of organs, soft tissues, bones and virtually all other internal body structure.
What does the measurement in MRI in terms of timing?
Measures the returning timeof different tissues in different environment.
What is the mechanism of MRI (i.e. being composed of what)?
organ (brain) -> tissue -> cell -> molecule -> atom -> proton
What direction is the proton?
Every proton has a spinning direction and it is not static.
What does MRI target on?
Behaviour of protons
How does MRI measure the returning time?
MRI applies magnetic field to align with the direction of protons. Then radio frequency is applied to turn the direction of protons. Then, the removal of radio frequency will return to the orignal state to align with magnetic field. The returning time for different tissues are different.
What does different colour for MRI infer?
- light pixel indicates a shorter returning time (e.g. in water)
- dark pixel indicates a longer returning time (e.g. in blood)
What is the measurement of fMRI?
Changes in blood oxygen level (assumed to reflect neuronal activity) [try to measure the the temporal variation of blood dynamics]
What does fMRI produce?
Produce a 3D image of activation maps showing which parts of the brain are involved in a particular mental process
The signal of MRI is being measured by MRI as a function of what?
A function of time that can infer the functions
Is fMRI invasive/ non-invasive?
Non-invasive
What does DTI rely on?
Magnetic Resonance Imaging (MRI) signal detection
What is the measurement of DTI?
Water flow direction (about the diffusion of water)
Is DTI invasive/ non-invasive?
Non-invasive