Adolescence Until 32? Scientists Map the five distinct phases of the brain.

A major study from the University of Cambridge, involving nearly 4,000 brain scans from participants between infancy and age 90, suggests that the human brain moves through five distinct phases. Crucially, the adolescent period may extend far longer than traditionally believed, potentially lasting until the age of 32.

The study, published in Nature Communications, found four significant turning points in brain development: ages nine, 32, 66, and 83. The brain is mapped through the following eras: Childhood (birth to nine), Adolescence (nine to 32), Adulthood (32 to 66), Early Aging (66 to 83), and Late Aging (83 onwards).

The period from age nine to 32 is characterized by a long stretch of heightened efficiency as the brain rapidly restructures its neural networks. This phase is also when the brain reaches its most efficient point and is often associated with the emergence of mental health vulnerabilities. Adulthood, starting at 32, is defined by stability and a plateau in intelligence and personality. Researchers used MRI diffusion scans to map neural connections across the lifespan, noting that brain architecture shows markedly different characteristics during each epoch.

Beyond the major developmental findings, new reports highlight significant environmental and lifestyle health risks:

• Vaping Contamination: A study found that e-cigarette mouthpieces are highly contaminated with bacteria, sometimes carrying up to 2,300 times more microbes than a public toilet seat (50 CFUs per square inch). Laboratory analysis revealed over 1.5 million colony-forming units (CFUs) on the mouthpiece. Identified species include Bacillus, Staphylococcus, yeast, mold, and fecal bacteria like E. coli and Enterococcus. Experts attribute this high contamination largely to poor cleaning, frequent handling, and placing the devices on various surfaces.

• Air Pollution’s Link to Blood Health: Experts warn that air pollution, such as the toxic air recently recorded in Delhi (AQI of 293, equivalent to smoking nearly nine cigarettes per day), impacts far more than just the lungs. New research suggests ambient air pollution disrupts iron balance, triggers inflammation, and contributes to cellular iron deficiency. This can lead to an increased risk of disorders like anemia and blood clots. Furthermore, long-term exposure to pollutants like PM2.5 and PM10 has been linked to an increased risk of blood cancer, potentially rising by 15 to 40% depending on the exposure level.

• The Chill Factor: Dental Strain: As regions like the UK experience some of their coldest autumns in 15 years, a Yorkshire dentist advises that freezing temperatures can strain teeth. Cold weather can trigger sudden sensitivity—a sharp, electric twinge—as teeth contract quickly, irritating nerves. Other common cold-weather issues include toothaches caused by sinus pressure pressing on the roots of the upper teeth, a lack of protective saliva due to dry mouth, and making small hairline cracks in the enamel more noticeable.

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🔖 Sources

Human brains have 5 distinct 'epochs' in a lifetime, study finds

Are You Still An Adolescent At 32? Study Says Yes

Does adolescence last until 32? Scientists unlock brain’s five eras

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Keywords: Adolescence

Adolescence

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