Human Adolescence: Such a development would be not unlike how adolescent humans learn to take on responsibilities and grow out of childish self-centeredness as they leave the nurturing environment of a nuclear family and venture out into the indifferent and competitive wider society, a diametric reorientation. Some evidence suggests humans become increasingly civic minded and socially responsible as standards of living rise, perhaps because at some point rising material living standards yield decreasing marginal satisfactions and other aspects of overall well being become increasingly important.
Cortical thinning is a process that starts in either late childhood or early adolescence. The brain begins to prune redundant synapses and shrinks its outer layer. Some scientists frame the process as the brain rewiring itself as it matures, increasing its efficiency. The process is known to accelerate in stressful conditions and accelerated thinning is correlated with depression and anxiety. Cortical thinning occurs throughout the human lifespan.
To Aristotle, youth is characterized by the development of physical strength and the pursuit of education. Middle age involves active participation in civic and political life, while old age, the repository of knowledge and experience, highlights the virtues of patience, contemplation and wisdom, a sequence of physical development, relational participation in society, and contemplative spirituality.
I’d characterize human life phases a little differently. In childhood the emphasis is on physical growth. After passing through puberty, an adolescent transforms restructures physically, maturing sexually and also restructures their thinking with education and career training in preparation to be able to step out into the adult world, fully mature, to make a contribution to society, raising a family and offering their services at work or in other ways, and thereby self-actualizing and realizing their highest spiritual potential. Old age and decay are phases I’m ignoring for this analysis.