27 June 2008

Brain weight matters

The weight of a baby's brain is important as a healthy weight indicates healthy development.

Weighty matters

  • 350g:
    This is about 10 per cent of body weight. The tripling of brain weight during the first year is unique to humans, who are born with relatively undeveloped brains (otherwise the baby's head would not pass through the birth canal). The adult brain weighs 1,4 kg, about 2 per cent of body weight.
  • 1kg:
    Age 1

    At one year babies can control many voluntary movements, thanks to development in the frontal lobes.
  • 1,15 kg:
    Age 2

    A baby brain weighs 80 per cent of an adult brain.
  • 1,2 kg:
    Age 6

    Because the language areas of the brain are well developed, advanced verbal abilities exist. Children have an impressive vocabulary, understand grammatical rules (such as creating plurals) and use past, present and future tenses without being aware of what they are doing.
  • 1,3 kg:
    Age 13

    During puberty hormones play an important role in brain development.
  • 1,5 kg:
    Age 18

    In young adults the prefrontal lobes, which are involved in judgement and behaviour, may not be fully mature.
  • 1,35 kg:
    Age 75

    Brain weight is declining but many cognitive abilities remain as good as ever.

Question and Answers
Q: Do smart parents have smart kids?
A: Although there is a strong link between genes and intelligence, the changes in brain structure are not necessarily genetically predestined. The brain's development is intimately linked to interactions with its environment.

Q Do people with higher IQ's have larger brains?
A: No, but their brains develop differently because the pruning of unused cells and connections leads to an increase in the brain's efficiency.

This is my simple religion. There is no need for temples; no need for complicated philosophy. Our own brain, our own heart is our temple; the philosophy is kindness

A 'happy' brain can help fight off infections. The body's immune system responds directly to changes in the brain. Within four days of a sad event, such as the death of a loved one, there can be a measurable reduction in the number of infection-fighting blood cells.

Did you know?
The brain can alter almost any body function. If you imagine you're warm you can increase the temperature in your fingers by more than 1°C!

Anyone home? The following factors may impede or limit development of the frontal lobes, the seat of reason

  1. A lack of sensory stimulation, lack of movement and lack of touch.
  2. Exposure to electromagnetic fields, TV, computers and video games (which causes desensitisation to violence, decreased imaginative development and less interactive communication).
  3. Nutritional factors such as inadequate amounts of protein, lack of essential amino acids and fatty acids, high carbohydrate and sugar diets and inadequate water consumption.
  4. Rigid educational systems, inappropriate curricula and inattention to unique learning styles can also be blamed for limited development.
By David Moseley and the Health24 team

YOU Pulse; Summer, December 2007


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