neuroimaging

Question 1

MRI

Answer 1

scan and create images of brain structure

beneficial to detect brain abnormalities
test structural differences in brain

Question 2

how does an MRI work

Answer 2

large magnets

take slices to construct a 3D model
- coronal plane
- horizontal plane
- sagittal place

lots of images taken in rapid succession whilst people do things
enables us to look at brain function

Question 3

how does an fMRI work?

Answer 3

determines activity by detecting changes in the magnetic response of haemoglobin

iron molecule found in haemoglobin gives blood magnetic properties

when magnet presented to brain, haemoglobin molecules line up

haemoglobin lose oxygen in areas of high brain activity
makes haemoglobin more magnetic and therefore molecules respond stronger to magnetic field

measured changes are BOLD
blood oxygen level dependant

Question 4

the haemodynamic response function

Answer 4

cant measure neuron spiking
only measure th energy craving after the activity
indirect measure of neuron activity
measures metabolic consequences 4-6 seconds after

Question 5

PET scan

Answer 5

uses same machine as an fMRI

radioactive crater substance injection to make blood flow more visible

more direct measure of blood flow compared to magnetic field differences

Question 6

subtraction method

Answer 6

used to see specific brain functions
keep entire environment the same except what is being observed
can be compared to show difference

measure 2 variations of same mental function
only differ in one aspect
observed difference must be due to variation

Question 7

PET vs fMRI

Answer 7

PET has better:
signal to noise ratio
higher sensitivity to blood flow
movement less problematic

fMRI better:
resolution
clearer image
more accurate - better to detect locations
quicker than PET
but prone to movement artifacts (noise)

Question 8

diffusion tensor imaging DTI

Answer 8

makes nerve fibre tracts (physical connections between neuron tracts) visible
can be used to build realistic models of neural structures

explains how far away areas of the brain can work together to complete a function

Question 9

central principle of cognition

Answer 9

most of our experience is multidimensional
specific functions are both localised and distributed across different areas

Question 10

functional connectivity

Answer 10

when neurons work in synchronisation during certain tasks
neurons do not need to be physically connected to work together and form neural networks

Question 11

empirical methods

Answer 11

used to experimental confirmation, exploration and debunking

behaviour
self report
- questionnaires and interviews

observable
- reaction times an pupil dilations