Prematurity Flashcards

1
Q

Prevalence and Aetiology of Prematurity

A

Average 1 in 10
->1 million die each year

Known causes:

  • Multiple pregnancies
  • Infections
  • Chronic conditions – diabetes, high BP
  • Genetic contribution

Not all causes are known

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Cognitive Outcomes: EPiCURE study

A

Extremely premature

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Cognitive Outcomes: Johnson et al. 2009

A

> 50% will have cognitive difficulties
Perform less well in a number of domains: >Language, literacy, numeracy and EF
IQ 10-20 points lower

Brain abnormalities are common and linked to early developmental outcomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Neural Explanation behind lowered Cognitive Outcomes:

A

WM and CC = IQ
Development of WM during preterm phase is highly important!

  • IQ related to gestational age
  • Periventricular WM reduction and reduced CC
  • Prems reduced WM – regardless of lesion or not
  • > 70% of variance in IQ explained by: GLOBAL WM volume and CC volume
  • ->100ml reduction in WM = 18 point drop
  • ->100m2 in CC = 8 point drop
  • Reduced WM volume and parent rated behaviour difficulties
  • Correlates with GCSE passes
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Neural Explanations: Speech

A

Language deficits more common in Prem Adolscents (Northam 2012)

> Children with a lesion at cUS at birth
L.lateralisation at follow-up – linked to speech/oromotor difficulties

> Left posterior Limb of the internal capsule (PLIC) + left primary motor tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Neural Explanation: Language

A

Language deficits more common in Prem Adolscents (Northam 2012)

WM and CC = Language

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Neural Correlates of Intelligence:Hypothesis 1: BRAIN VOLUME = IQ

A

R = 0.3-0.4 (Luders 2009) = 10% of people
- driven by genes (Posthuma 2002)

Intelligence and volumes of frontal, parietal, temporal cortices + hippocampus r= Less that .25

IQ is related to thickness in PFC and Temporal lobes

Developmental trajectory:
- Smarter: Early childhood = thin cortices;
Until puberty = increase PFC and Temporal; then decrease

Anecdotal:
Lesion size = IQ – NO!
Scan of large lesion: actual volume of GM/WM is normal
Scan of small lesion: actual volume of GM/WM is reduced

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Neural Correlates of Intelligence:Hypothesis 2: P-FIT theory

A

Parieto-Frontal Integration Theory

Extrastriate Cortex (18-19) + Fusiform Gyrus (37) ==> recognition, imagery and elaboration of visual input
Wernicke’s area (22) ==> syntactic auditory input
Supramarginal (40) + superior parietal (7) + angual gyri (39) ==> captures sensory information and turn into symbolism, abstraction and elaboration
Parietal interact with Frontal regions = Working memory network to compare different responses
6, 9, 10, 45, 46, 47
Anterior Cingulate Cortex (32) ==> support inhibition of alternate responses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Small world Network

A

Higher intelligence = uninterrupted information transfer among the brain regions

New studies have found positive correlations between:
Intelligence N-Acetyl aspartate
Water Diffusion in centrum Semiovale (DTI) Intelligence

FMRI studies

  • Distributed Network (similar to P-FIT)
  • More efficient processing – especially in Frontal and Parietal
  • ->Use fewer brain resources
  • ->Resting brain network (less activity in a frontal and parietal network) linked to frontal and parietal regions activated in high cognitive tasks
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Neural Correlates of Intelligence:

Hypothesis 3: CC

A

Einsteins anterior and posterior CC = larger

Particularly connections of parietal lobes (Mathematical reasoning?)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Neural Correlates of Intelligence:Hypothesis 4: Lesion distribution

A

Glascher et al. 2009 & 2010

Specific WM lesions linked to domain specific deficits in adults

  • left inferior frontal cortex for VCI,
  • left frontal and parietal cortex for WMI
  • right parietal cortex for POI
  • No single location for PSI

Intelligence draws on connections between regions that integrate verbal, visuospatial, working memory, and executive processes.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Sickle Cell VS. Prems: WM & IQ

A

Global WM modest relation to IQ
- Unlike PREMS!

Focal WM density reduction = main contributor to IQ decrement
- Unlike PREMS!

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Brain development + Prems

A
  1. Early Fetal Phase
    Thalmocortical connections
  2. Early Premature Phase 23-32 weeks
    Cortico-cortical projection
    Callosal Projections
  3. Late pre-term phase 32-36 wks
    U-fibres
    Retraction of callosal fibres
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Biomarkers + Intervention

A

Early intervention trial: Erythropoietin

a drug that prevents WM injury
–>there is a positive effect on WM development - we do no know impact behaviourally yet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Biomarkers of Prems

A
Reduced WM
reduced CC volume
Reduced GM volume
Left laterisation lesion = oromotor difficulties
Temporal Splenium + AC = 57% of variance
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Cognitive explanation behind lowered abilities

A

Lowered IQ impact performance on tests of other domains

IQ and memory/language/processing speed= 0.7+ Deary et al. 2010

17
Q

LI not assciated with:

Northam 2012

A

Arcuate Fasciculus

18
Q

LI associated with:

A
  1. Posterior CC – Splenium
    - ->Temporal lobe connection were only reduced

But only in conjuction with: small anterior commissure

=> Temporal Splenium + AC = 57% of variance

  1. Bilateral volume reduction in ventral language pathways