Khaberni - A recent scientific study has revealed that human adolescence extends into the early thirties, identifying four key age milestones that are major turning points in brain development at ages 9, 32, 66, and 83.
The study, conducted by researchers at Cambridge University and involving the analysis of more than 4,000 images of brains of individuals ranging from birth to 90 years old, showed that the brain goes through five distinct stages from childhood to late old age, with substantial changes in the networks of communication between nerve cells.
The results, published in the journal Nature Communications, show that the brain does not grow along a fixed path, but instead progresses through leaps and shifts in efficiency, which explains the varying risks of psychiatric disorders and dementia throughout the lifespan.
Five stages of the brain’s journey through age:
- Childhood (birth – 9 years)
The brain grows rapidly, but it also discards excess neural connections, making it less efficient and operating in an indirect way similar to "aimless wandering".
- Adolescence (9 – 32 years)
This is the most significant turning point, as the brain suddenly becomes more efficient, and the risks for psychiatric disorders increase. The study confirms that the brain's functional peak occurs in the early thirties, indicating that adolescence extends much longer than previously thought.
- Maturity or Adulthood (32 – 66 years)
The brain enters the longest period of stability, while efficiency gradually declines. This stage aligns with "the stabilization of intelligence and personality," according to the researchers.
Early old age (66 – 83 years)
The pattern of neural connectivity alters to become more fragmented into groups that function separately, which is the period when diseases such as dementia and high blood pressure begin to affect brain health.
Late old age (83 years and above)
The aforementioned shifts enhance but become more pronounced, with limited data due to the scarcity of healthy brains at this age.
In her words, Dr. Alexa Mosley, the lead researcher of the study, said that the brain continually reconnects itself across life stages, but not in a smooth pattern; there are sharp changes that recur at specific ages.
She explained that these ages notably coincide with stages like adulthood, social changes in the thirties, and the onset of health issues later on.
Professor Duncan Astle from Cambridge University mentioned that the way the brain networks directly relates to developmental and psychological disorders, and that network differences affect attention, language, and memory.
Professor Tara Spires-Jones from the University of Edinburgh described the study as "fascinating", adding that it aligns with scientists' understanding of age-related brain changes, emphasizing that the timing of these changes varies among individuals.
