Neuroimaging Flashcards
what is the leading cause of disability in higher income countries
unipolar depression
CV disease
dementia
alcohol use
MRI uses
physiology
impact of drugs
hormones
pros and cons of MRI
expensive
safe
uses of CT scans
used in response to trauma
MRI
observe tissue loss/risk of AD (tissue loss occurs prior to AD clinical symptoms)
1mm resolution
motion insensitive imaging
movement (due to ADHD/psychotic episode) causes blurred images
uses reference point
conditions which increase/decrease hippocampal volume
increase: bipolar
decrease: PTSD/major depression/schizophrenia/AD
schizophrenia volume changes
increases lateral ventricle/putamen volume
decreases amygdala/grey matter area
AD MRI
increases in grey matter
predict who gets AD
66% accuracy of structural MRI
ARMS
at risk mental state can develop into psychosis
increased seizures causes increases risk of brain damages
ARMS-T (transition)
ARMS-NT (no transition)
diagnosis of movement disorders
PD (aggressive)
multiple systems atrophy (MSA)
progressive supranuclear palsy (PSP)
92% diagnosis accuracy
MRI is translational
can be used in rodents (more expensive equipment, increased magnetic current)
produce spinecho1
40 slices @ 400um
can be used to compare AB burden
MRI for spinal cord
image multiple sclerosis rodent models
MS lesions appear in SC
image water signals in the brain - water binds to myelin sheath in axons
understanding demyelinating disorders
demyelination occurs in later life/ early life myelination occurs
frontal cortex is the last area to myelinate
develop silent mRNA
MRI signal
brighter signal = more anisotropic activity
view where white matter tracts flow
stroke in females and males
loss of language ability/aphasia
females have higher bilateral language networks vs males (females have better recovery)
stroke lesion size
larger lesion - greater effect of stroke
MCAo - similar to ketamine
MK801 perfusion MR imaging shows smaller perfusion/infarction - increased chances of survival
poor perfusion - less chances of survival
give aspirin/surgical intervention/SC therapy to repair lesion
use of proton MR spectroscopy
analyse brain chemistry (choline/creatinine levels)
develop non-DA schizophrenia therapy
BOLD in fMRI
blood oxygenation level uses haemoglobin
after deoxygenated - becomes MR sensitive
function brain activity during task
pain matrix
sensory discriminative - intensity site
cognitive evaluative - attention/anticipation
affective motivational - emotional valence
cognitive impairment risk
lower cognition means a greater risk of developing a psychiatric condition
how to assess cognition
morris water maze
neocortical lesion - no effect
hippocampal lesion - longer time and distance to podium
virtual arena task
opioid addiction
monetary incentive delay task
analyse hedonic/reward network
areas activated: occipital/motor cortex, N.accumbens, caudate, insula, thalamus, thalamus, dorsal midbrain
arterial spin labelling cASL
used to quantify CBF changes in drugs/ageing/stroke