Brain has five ‘eras’, scientists say – with adult mode not starting until early 30s

A comprehensive study by Cambridge University identified five major 'epochs' of human brain development, marked by four pivotal 'turning points' at ages nine, 32, 66, and 83. The study, based on brain scans of nearly 4,000 individuals aged one to 90, revealed that brain development occurs in distinct phases, with significant shifts in neural wiring and efficiency. The childhood phase, from birth to age nine, is characterized by 'network consolidation' and a decrease in wiring efficiency. The adolescent phase, up to age 32, sees increased efficiency and refinement of brain connections. Adult mode, starting in the early 30s, is the longest phase, lasting over three decades. The 'early ageing' phase begins around age 66, followed by 'late ageing' at around 83. These findings could provide insights into mental health disorders and the effects of life events on brain development.