Equal numbers of neuronal and nonneuronal cells make the human brain an isometrically scaled‐up primate brain

@article{Azevedo2009EqualNO,
  title={Equal numbers of neuronal and nonneuronal cells make the human brain an isometrically scaled‐up primate brain},
  author={Frederico A. C. Azevedo and Ludmila R.B. Carvalho and Lea Tenenholz Grinberg and Jos{\'e} Marcelo Farfel and Renata E. L. Ferretti and Renata Elaine Paraizo Leite and Wilson Jacob Filho and Roberto Lent and Suzana Herculano‐Houzel},
  journal={Journal of Comparative Neurology},
  year={2009},
  volume={513}
}
The human brain is often considered to be the most cognitively capable among mammalian brains and to be much larger than expected for a mammal of our body size. [] Key Method Here we determine these numbers by using the isotropic fractionator and compare them with the expected values for a human-sized primate. We find that the adult male human brain contains on average 86.1 +/- 8.1 billion NeuN-positive cells ("neurons") and 84.6 +/- 9.8 billion NeuN-negative ("nonneuronal") cells. With only 19% of all…
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