Brain Structure and Function

, Volume 213, Issue 4–5, pp 365–366 | Cite as

Are there ten times more glia than neurons in the brain?

  • Claus C. Hilgetag
  • Helen Barbas
Brain Mythology

Neuroscience students take it for granted that there are many more glia than neurons in the brain. Neuroscience textbooks state with confidence: “Although there are many neurons in the human brain…, glia outnumber neurons by tenfold” (Bear et al. 2006) or, not to be outdone, even by “10–50 times”, as claimed in another text (Kandel et al. 2000). This fact is happily invoked by gliologists to promote the status of their field.

Given this well-accepted figure, we were surprised when our cell counts in the prefrontal cortex of the rhesus monkey turned up a glia-to-neuron ratio (GNR) of just about 1 (Dombrowski et al. 2001). There was some regional variation, but no prefrontal area had a GNR larger than 1.2. Maybe the proportion of glia is very different in other cortical regions or other parts of the brain, so that the overall ratio for the whole brain is much larger than 1? Classic studies, however, conducted by O’Kusky and Colonnier (1982) in the opposite pole of the brain, the visual...


Rhesus Monkey Total Cell Number Healthy Young Male Cell Counting Method Glial Progenitor Cell 
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Copyright information

© Springer-Verlag 2009

Authors and Affiliations

  1. 1.School of Engineering and ScienceJacobs University BremenBremenGermany
  2. 2.Department of Health SciencesBoston UniversityBostonUSA

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