SCIENCE: Recent Studies on the Growth of Brain

Brain continues to grow and reorganize accross the life span of homosapiens. There are 5 major epochs of brain development. As per the new study the adulthood start at the age of thirty two. Other new findings highlights how factors like exercises can influence brain growth, even into adulthood, while the creation of multi-person brain organoids or kimroidoids offers new ways to study development of disease in a more accurate way than previous models. 

Brain Development Stages 

° Recent research has identified five distinct stages of brain development or epochs, that are characterized by different patterns of rewriting. 

° These stages are childhood (birth to 9 years), adolescence (9 to 32 years), adulthood (32 to 66 years) early aging (66 to 83 years) and late aging (83 onwards)

° The adolescence phase is a significant period of neural efficiency which extends beyond the traditional teen age years.

Mechanisms of Growth & Maintenance 

° Exercises: Aerobic exercise had been shown to promote neuro genesis (the creation of new neurons) and increase Brain Derived Neutrophic Factor (BDNF), which is crucial to nerve health.

° Experience: Learning and experience-dependent neuroplasticity shape the brain throughout the life, with specific period of intense growth and reorganization occuring in childhood and adolescence.

Genetic & Environmental Factors 

Genetics, nutrition and other environmental factors all play a role in shaping the brain's development from prenatal stage and after birth.

New Tools & Technologies 

° Kimroidoids: Scientists are creating  3D organoids [1] from cells from multiple people to better model how different people respond to drugs and how variations in brain development occur.

° Advanced imaging: Techniques like two-photon microscopy allow researchers to observe structural changes in the brain in real-time, providing deeper insights into how the brain develops and remodels itself.

Are these findings contradict the earlier finding that the brain achieves 90% growth by the first three years and the remaining 10 % by 23 years?

No, these findings do not contradict the earlier findings. They refer to different aspects of brain development: physical size versus functional maturation. The brain's volume mostly develope in the early childhood, while the refinement of its structure and organisation continues for much longer.

The Process of Maturation 

The apparent difference is a matter of developmental process.

Physical size and volume

The claim that brain reaches 80 - 90 per cent of its volume by the age of 3 to 5 is accurate.  The early phase involves rapid cell proliferation (neurogenesis and gliogenesis) and initial formation of vast number of neural connections (synaptogenesis)

° Functional maturation and rewriting: 

The finding that the brain continues to develop until mid 20s or later refers to the complex process of maturation, organisation and fine-tuning of those connections.

The Process of Maturation 

This later development involves several key processes that optimize brain function.

° Synaptic Pruning: The brain overproduces connections in early life and then eliminates the less used ones during childhood and adolescence to become more efficient.

° Myelination: The process of forming a fatty sheath (myelin) around nerve fibres, which speeds up information transfer, continues into

adulthood.

° Regional development: Different brain regions mature at different rates. The prefrontal cortex, which handles higher-level actions like planning, decision-making, and emotional control, is one of the last areas to mature, often not until

around age 25 or later.

In short, the early brain is built with abundant raw material (size and initial connections) and subsequent decades are spent sculpting that material into an efficient, specialized, and fully functional adult brain.

Notes:-

1. 3D organoids are a miniature, three dimensional structures grown from stem cells or primary tissues that mimic the complexity and function of real organs. They are used in research, drug discovery and regenerative medicine because they provide more physiologically relevant model than 2 diamentional cell cultures.