Citation

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

Frederico A.C. Azevedo, et al.

Journal of Comparative Neurology (2009)

TL;DR

Human brain contains ~86 billion neurons

Established that the human brain contains approximately 86 billion neurons using the isotropic fractionator method, revising earlier estimates that ranged from 10-100 billion. This precise count is essential for understanding the scale of human neural network topology and the metabolic/wiring constraints that shape brain architecture.

Key Findings from Azevedo & al. (2009)

  • Human brain contains ~86 billion neurons
  • Roughly equal numbers of neuronal and non-neuronal cells
  • Human brain is isometrically scaled primate brain (not qualitatively different)

Related Mechanisms for Equal numbers of neuronal and nonneuronal cells make the human brain an isometrically scaled-up primate brain