How do you describe a newborn’s brain?

As so well explained in Dr Robin Fancourt’s book Brainy Babies, a newborn’s brain is quite spectacular as it is already two-thirds the size of an adult’s, and it already contains almost all the neuron cells it will ever have: one hundred billion brain cells, with their axons being wrapped by 10 times as many myelin cells that nurture and protect them like ‘the bubble-wrapping of a parcel’. But, unlike the newborn’s other organs, the majority of their brain cells are still immature, i.e. most of their brain’s neurons are not as yet performing their ultimate functions, as they are not yet fully myelinated or connected to communicate with other brain cells.