Health Sciences 2700A/B Lecture 4: Infant (0-2 years)
18 Jan 2020
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Document Summary
In the first years, infants grow 25-30cm and triple their body weight. Two year olds have proportionally larger heads - as they need to hold their nearly full sized brain. Synaptogenesis (creation of synapses) - is followed by a period of synaptic pruning to make the nervous system more efficient. Neuroplasticity - the brain"s ability to reorganize neural pathways and connections. Myelination - myelin gradually covers individual axons and electrically insulates them from one another - improving conductivity. Controlled by primitive parts of the brain. These reflexes disappear by about 6 months of age. A soft touch on the cheek will cause an infant to turn toward the touch and open the mouth - disappears by about 3 months. Stroking the sole of the foot causes the infant"s toes to fan out and up - disappears by about 12 months.
