Does the brain model Newton's laws?

  title={Does the brain model Newton's laws?},
  author={Joseph McIntyre and Myrka Zago and A. Berthoz and Francesco Lacquaniti},
  journal={Nature Neuroscience},
How does the nervous system synchronize movements to catch a falling ball? According to one theory, only sensory information is used to estimate time-to-contact (TTC) with an approaching object; alternatively, implicit knowledge about physics may come into play. Here we show that astronauts initiated catching movements earlier in 0 g than in 1 g, which demonstrates that the brain uses an internal model of gravity to supplement sensory information when estimating TTC. 

Paper Mentions

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  • Proceedings of the Royal Society B: Biological Sciences
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