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what?!!You are hardly in a place to discriminate..
That expansion produced a network of furrows that was remarkably similar to the pattern seen in a real human brain. This suggests that brain folds are caused by physics: the outer part grows faster than the rest, and crumples. Such straightforward, mechanical buckling is one of several proposed explanations for the distinctive twists and turns of the brain's outermost blanket of cells, called the "cortex".
The gel model started out smooth, like the brain of a 22-week-old foetus, and ended up with a pattern of folds similar to that of a brain at 34 weeks
Alternatively, researchers have suggested that biochemical signals might trigger expansion and contraction in particular parts of the sheet, or that the folds arise because of stronger connections between specific areas. "There have been several hypotheses, but the challenge has been that they are difficult to test experimentally," said Tuomas Tallinen, a soft matter physicist at the University of Jyväskylä in Finland and a co-author of the study, which appears in Nature Physics. "I think it's very significant... that we can actually recreate the folding process using this quite simple, physical model."
Surprisingly like the real thing: The finished, folded "gel brain"
Humans are one of just a few animals - among them whales, pigs and some other primates - that possess these iconic undulations. In other creatures, and early in development, the cortex is smooth. The replica in the study was based on an MRI brain scan from a 22-week-old foetus - the stage just before folds usually appear. A 3D printout of that scan was used to make a mould, which in turn was filled with a silicon-based gel to make the "gel brain". Finally, a 1mm-thick layer of slightly different gel was added to the surface - to play the role of the cortex.
Distinctive grooves