At the IAPCT Conference in Manchester in 2019, I asked Frans Plooij about the obvious cognitive developments after the (hypothesized) eleven levels of the hierarchy are established at 75-80 weeks of age. He suggested that this involved the cerebellum, pointing to its progressive expansion in mammals, then primates, then humans.
In 2022, I reviewed the structure and probable functions of the cerebellum and suggested ways in which these are admirably suited to reorganization processes in the ascending input and descending output connections between levels — perceptual input functions, error output ramification, and reference input functions — by means of neurochemical adjustments and rapid dynamic changes in excitatory and inhibitory connections.
Reorganization changes the topology of the brain more widely than in the cerebellum. Recent research has found predictable structural changes in the brain at ages 9, 32, 66, and 83. Here is a lay article:
The research into ‘topological turning points’ is summarized in Nature Communications: