Zusammenfassung der Ressource
Neuroimaging
- Structural Imaging
- What the brain looks like
- Dissection
- When brain is out of skull
- Examine for gross lesions e.g.
physical damage/infection/stroke
- Thin slices
look at cell
damage eg.
tangles in
alzeimehers
- CT Scans
- Computorized Tomography
- Thin slice xrays
that can be
assembled into 3D
data structures to
use clinically
- different tissue absorbs
radiation to dif. extents
e.g.brain, skull,
ventricles
- MRI Scans
- Magnetic Resonance Imaging
- Head placed in
strong magnetic
field to align
protons, radio
frequency knocks
them out of
allignment
- It measures
radiowaves
emitted as it
re-aligns - gives
high resolution
pic of braim
- diffrenciates
grey from white
matter
- DTI Scans
- Diffusion Tensor Imaging
- way of analysing MRI data
- looks at direction of
diffusion and the nerve
fibre tracts in brain (white
matter
- Functional Imaging
- Looks at brain in action/what it is doing
- PET Scans
- position emission tomography
- radioactive tracers
in bloodstream
then measure
positiron particles
emitted
- worse
resolution
that MRI but
has
advantages
- FMRI Scans
- Functional MRI
- Same techniques as
MRI, measures BOLD
(brain oxygen level
dependant) response; a
distortion due to
'deoxyhaemoglobin'
- its sensitive to
blood flow &
oxygenation so
assumed to
correlate with
neural activity
- It maps out
what bits do
what and tests
theories e.g.
individual
differences
- MRI Spectroscopy
- Magnetic Resonance Imagery
- Analysic techniques
measure relative
concentrations of diff
biological chemicals
e.g. neurotransmitters
- EEG
- Measures small voltage on scalp due to brain 'generators'
- Net/cap electrodes on scalp
- good at measuring timing but not location
- Electro encephalt graphy
- ERPs
- Event related potential
- Evoked electrical
pattern creates
temporary precise
patterns of voltage
(can be removed -
not phase locked)
- Very
variable
and noisy
- MEG
- Magnetoencephalography
- Measures
magenetic field
around head
due to the
electrical fields
in the brain
- Good at
timing
and
localising
- No fiddily
electrodes
- Better at things
that EEG and
vice versa
- Other Types
- Brain Stimulation
- very quick/strong
magnetic field induces
brain current which
intereferes or
stimulates an area;
sing pulse
Transcranial magnetic
stimulation (TMS)
- Continous TMS
- Interferes for longer
and has greater
effect; manipulates
timing relative to
sensory stimulous