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 How the fetal brain wires up for action

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عدد الرسائل : 281
العمر : 33
الجنسية : lebanese
الجنس : female
المهنة : laboratory clinic
تاريخ التسجيل : 24/01/2009

مُساهمةموضوع: How the fetal brain wires up for action   السبت 07 فبراير 2009, 23:15

BEFORE a fetus is born, its brain undergoes the complex process of

the connections between its different regions. Now a computer model is showing us how.
Although our genes provide an initial blueprint for the way different neurons connect together, the developing brain must still refine the wiring and prune out any redundant connections. "It's a big challenge to have a system that is ready by the time of birth so that newborns can begin experiencing the world right away," says Jean-Philippe Thivierge from Indiana University, Bloomington.The developing brain must refine its wiring and prune out any redundant connections before birth




Neuroscientists suspect the brain achieves this by sending out waves of spontaneous electrical activity that cascade across groups of neurons, helping it to scout out the relative positions of neurons and forge the most efficient network.
To investigate the exact nature of this process, Thivierge created a computer model of 1000 neurons that simulates the way the retina connects to the region of the mid-brain that controls eye movements, called the superior colliculus.
The model revealed that weak waves of activity over a small number of neurons were the most efficient at forging new connections, rather than big waves that sweep across the whole region. Timing also proved to be critical, with fluctuations as short as a millisecond instrumental in the wiring process (Neural Networks, DOI: 10.1016/j.neunet.2009.01.001).

  • From issue 2694 of New Scientist magazine, page 19. Subscribe and get 4 free issues.
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How the fetal brain wires up for action
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