developmental milestones Flashcards
primary brain
vesicles and flexures
6 weeks
more flexures and swellings
10 weeks
cerebral explansion and commissures
3 months
basic structures established
5 months
CNS myelination begins
7 months
lobed cerebrum
9 months
gyri (ridge) and sulci (furrow)
myelination
before PNS/SC/brain
compostion changes
Galactolipids
Protein components
Begins ~5th month in humans; 10 days postnatal in rat
At peak, oligos produce 3x ‘body weight’ per day
Most over by 2 years, some in late teens (neocortex)
rubella
german measles heard immunity vaccine abnormalityoes dependent on time of infection of virus 6th week- eye malformation e.g. cataract 9th week- deafness - organ of corti cardiac malformation 5-10th weeks CNS disorders in 2nd trimester risk falls after 16 weeks
fetal alcohol syndrome
dose dependent (more alc more probs) difficult to ascertain lower limit of alcohol comsumption Alcohol crosses placenta. Fetus doesn’t clear alcohol well. \ Fetal levels higher.
fetal alc syndrome symptoms
Microcephaly Loss of cells Loss fibres e.g. callosal agenesis Disturbed migration Irritability Motor and intellectual impairment
FAS facial abnormalities
discriminating features: short palpebral fissures flat mid face short nose indistinct philtrum thin upper lip
associated features epicanthal folds low nasal bridge minor ear abnormalities micrognathia
opiates
neonatal withdrawal
cocaine
hypoxia, abortion, withdrawal impaired cognition
ecstasy
long term effects on hippocampus
cannabis
long term cognitive effects
maturation of axon conduction velocity
Speed of conduction with myelination Neonate peripheral nerve ~ 20 - 25m/s 1 – 6m 32 – 50m/s 6 – 12m 33 – 60m/s 12 – 24m 40 – 60m/s
‘when does the foetus feel pain’ - sensation
2 reviews
Royal Coll. Obs. Gynae. 1997 and 2010 reviews.
Somatosensory input e.g. pain, requires connection of receptors, sensory neurons, thalamus and cortex.
Is when pain the circuitry for pain reflex has developed
stages of development of sensation
Innervation of dermal skin from 28 weeks / subdermal from 6 - 8 weeks
DRG connection to spinal cord from 8 weeks. Non - noxious.
C – fibre (noxious stimuli) connection from 19+ weeks.
Reflex response to noxious stimuli in 23 week preterm infants.
Facial responses to heel lancing from 28 weeks.
Organised thalamus forms from 8+ weeks.
Retinal inputs arrive at 14 – 16 weeks.
Myelination from 25 weeks.
Connections from the thalamus to cortex from 24 weeks. (Sub-plate 12+)
Evoked potentials in the cortex from 29 weeks (RCOG) or earlier (26 weeks e.g. Taylor et al 1996).
Recent imaging studies suggest 24 week cortical responses.
taste and smell
Well developed at birth.
Differentiate mother / non-mother breast pads.
Bottle-fed prefer any lactating female.
hearing
Responsive at birth.
Excellent discriminators of phonemes
Locate sounds from 3 days.
vision
Eyes open and sensitive from 7 months. Vision least well developed at birth. Retinal cells sparse and not mature. Optic nerves not myelinated. Vision blurred – sharper by 6 months. Development of ocular dominance columns Colour vision develops – good at 2 months.
motor
Spontaneous muscle twitches
Writhing from E28 – 32.
Increases to birth.
postnatal reflexes: moro
(startle) reflex
Baby supine – remove head support.
Trunk extension.
Cycle of limb extension (adbuction - from midline).
And limb flexion (adduction - to midline).
Goes 3+ months
stepping reflex
Hold up, feet onto surface.
Goes 6 weeks
palmar grasp reflex
May support own weight.
Goes by 3-4 months
Development of inhibition
swimming reflexes
not all babies
may swallow
goes by 4-6 months
babinski reflex- sign
Neonates fan toes when sole stroked.
adults curl toes.
descending motor tract damage – fan.
rooting
stroke cheek
nipple seeking
goes 4-7 months
sucking
stroke lips
reaching
5th month after birth
around 8-9months attain objects
by 2 year show adult motor patterns
