Intelligence, Attention, and Brain Imaging Flashcards
what does iq stand for
intelligence quotient
when and why was the term iq developed
early 20th century to identify children struggling academically (sounds great but ended up being eugenics oops)
also og qs were culturally anchored to US, rooted
what is flynn effect
iq scores have been steadily rising for decades for reason, until recently and now its plummeting (commonly tiktok and short term attention span social media is blamed but unconclusive)
what makes a good cognitive test
mcq!
standardised so allows comparisons
reliable - same test 2x same results
valid - measures what is aimed to be measured
are iq tests reliable
hell yea
are iq tests standardised
yes
are iq tests valid
eh we dont know - what are they actually measuring?
what is the most common iq test
weschler adult intelligence scale
weschler adult intelligence scales result is called what
full-scale IQ
FSIQ
two sections FSIQ is broken down into
verbal IQ
VIQ
performance IQ
PIQ
two sections VIQ is broken down into
verbal comprehension index
VCI
working memory index
WMI
what is VCI - 4
vocab
similarities
info
comprehension
what is WMI -3
authentic
digit span letter-number sequencing
two sections PIQ is broken down into
perceptual organisation index
POI
processing speed index
PSI
what is POI - 3
pic completion
block design
matrix reasoning
what is matrix reasoning
test used in POI component
abstract nature its giving ucat tbh
abstract cog process - pattern finding
measures accuracy and speed
what is PSI - 2
digit symbol coding
symbol searching
what is the digit symbol coding test
tests PSI
blank sheet, numbers between 1-9 in rows, corresponding symbols, have to fill in
accuracy and speed
also abstract
how are iq scores mapped
they are ordinal - in order but arent fully scaled - e.g. score off 100 not twice as smart as 50)
averaged out at 100 , bell shaped distribution
0-130
iq and risk of death
higher iq = longer life
(number of deaths according to iq after 20 years were measured in the study)
what is iq correlated with -4
academics
job performance
income
crime? (or being caught)
*not absolute prediction dont be silly
prediction is heritable! but we dont know how or which genes contribute to iq - importance of synaptic plasticity?
what is iq not correlated with - 6
practical intelligence
emotional intelligence (potentially inverse)
long term memory
happiness
personality
motivation
what is spearman’s g
model of iq
performance of diff
cog tasks is correlated - verbal, spatial, numerical, reasoning (ie being good at one means ur likely to do well in others but not complete correlation)
this suggests general underlying factor for intelligence - g
AND
task specific factors - s (aka the non g stufff that is specific to being good at verbal, spatial, etc)
g can be split into …
fluid
crystal
what is fluid
unlearned
what is crystal
learned
link between iq score (or g) and brain size
eh
modest relationship at best
link between iq score (or g) and sex
no overall diff but
women better at verbal
men better at spatial
may be reflected in correlations with size of different brain regions
link between iq score (or g) and lateral part of prefrontal cortex
initally thought to be centre of intelligence as working memory is here
but probs just networks of structures
what are the main theories of the neurobiology of g - 4
parietal-frontal integration theory
multiple demand theory
process overlap theory
network neuroscience theory
what do we acc know about neurobiology of g - 4
some theories
efficiency and connectivity (between neurons) is more important than size of brain
myelination is strong predictor in early years
attention is fundamental to all models/ theories - in diff ways and diff elements/ areas but is always relevant
what is attention
ability to focus on a specific object, location, message or other stimulus
we have limited attentional resources to allocate
complex or novel stuff requires more
practice improves, becomes automatic
similar to/overlaps with cognitive overload
where is attention
various networks, depends on attention system
mostly parietal
what does the stroop task test - gorilla one
selective attention
what are the three main attention systems
alerting - basic, primal
orienting
executing - most complex
how many attention systems are there
3
what is alerting system
attends to danger/ safety
where is alerting system
subcortical
how is alerting system tested
by testing vigilance
tonic alerting - attention to low frequency events
if a snake was to come out of the floor, we attend to the threat although we are not constantly worried about it
think of it as a radar, activated by warnings
recruits autonomic nervous system, thalamus and limbic system
role of adrenergic system/ locus coeruleus
in ptsd, increases
noradrenaline system
important for attention but not sure why - all types
noradrenaline system made by what and projected where
made by locus coeruleus
project throughout cortex
noradrenaline system and ADHD
hypoactive in ADHD
ritalin, front line treatment for ADHD, keeps noradrenaline in synapse for longer
noradrenaline system can be targeted by -2- resulting in
ritalin in adhd
cocaine, amphetamine (psychostimulants)
result in inc attention
partially explains paranoia
what is orienting system
attention to sensory location or modality
watching tv, navigating traffic, catching a ball
attending to relevant elements of warning
where is orienting system
ventral frontal cortex - signals something new to attend to
signals to temporo parietal junction - allows us to break attention to what we previously were paying attention to prior to new signal
pulvinar nucleus of thalamus - initial filtering of external stimuli
what prompts us to attend to something
we are blind to something changing slowly
movement causes us to attend to it, esp in periphery view (evolutionary)
changes in lighting
emotionally salient things - if we were hungry and bowl of food changes or phobia of spiders and spider appears
what is executive attention
concentration, conscious controlled attention
top-down control, select and concentrate, filter out others
where is executive attention
potentially:
two separate networks, fronto parietal network (cables that connect parietal and frontal, allowing us to switch between tasks and initate focus)
and cinguloopercular network (allows us to maintain attention on something)
laterality and attention
right hemisphere is normally dominant for attending to sensory stimuli
esp orienting system - temporoparietal junction
right hemisphere lesion leads to
severe left neglect - hemineglect
left hemisphere lesion leads to
partial right neglect (as not dominant)
bilateral lesion leads to
severe right neglect
common cause of lesions
stroke
what is a stroke
when blood supply is limited
two types of stroke
ischaemic stroke
haemorrhagic stroke
what is an ischaemic stroke
most common
artery blocked by blood clot
cell death from hypoxia and lack of glucose
what is a haemorrhagic stroke
artery breaks or leaks
hypertension, aneurysm, etc
cell death from inc intracranial pressure and inflammation
hypoxia and lack of glucose
methods to observe human brain - 6
lesion/deficit model
ct scans - computerised tech
pet scans - positron emission tomography
mri - mag. resonance imaging
fmri - functional magnetic resonance imaging
eeg = electroencephalography
lesion/ deficit model
brain damage is linked to behavioural change - think phineas gage
lesion/deficit strengths - 3
direct
real, natural
can do pre and post behaviour and compare
lesion/deficit limitations - 3
variable
temporal challenges - change in behaviour will change over time
ethics - animal models often used
what is ct
computerised tomography
series of x rays
ct strengths - 5
quick
cheap
good visualisation of blood and bone
3d reconstruction
best in emergency
ct limitations - 3
uses ionising radiation
not good for soft tissue like brain
just gives snapshot in time
mri strengths - 3
soft tissue detail
different protocols depending on what you want to see
no radiation
mri limitations - 4
slow
expenny
claustrophobic
metal causes problem due to magnet used
what does a ct haemorrhage / bleed look like in right hemisphere
blood on right appears bright
midline shift towards left due to inc pressure (wonky spine vibes)
ventricles appear dark - compressed fluid, blood pushing and compressing ventricles
what does a ct ischaemic stroke look like/ blood cut off
large dark regions, esp on right
midline is normal as no blood leaking into brain, no inc pressure
78 yr old man is unconscious, suspected of suffering haemorrhagic stroke. most appropriate imaging method to test for this?
ct
