Open AccessCellular Scaling Rules for Primate Spinal Cords
Author(s) -
Mark J. Burish,
J. Klint Peebles,
Mary K. L. Baldwin,
Luciano Tavares,
Jon Kaas,
Suzana HerculanoHouzel
Publication year - 2010
Publication title -
brain, behavior and evolution
Language(s) - Uncategorized
Resource type - Journals
SCImago Journal Rank - 1.05
H-Index - 77
eISSN - 1421-9743
pISSN - 0006-8977
DOI - 10.1159/000319019
Subject(s) - spinal cord , neuroscience , primate , biology , cord , central nervous system , anatomy , neuron , nerve net , somatic cell , medicine , biochemistry , surgery , gene
The spinal cord can be considered a major sensorimotor interface between the body and the brain. How does the spinal cord scale with body and brain mass, and how are its numbers of neurons related to the number of neurons in the brain across species of different body and brain sizes? Here we determine the cellular composition of the spinal cord in eight primate species and find that its number of neurons varies as a linear function of cord length, and accompanies body mass raised to an exponent close to 1/3. This relationship suggests that the extension, mass and number of neurons that compose the spinal cord are related to body length, rather than to body mass or surface. Moreover, we show that although brain mass increases linearly with cord mass, the number of neurons in the brain increases with the number of neurons in the spinal cord raised to the power of 1.7. This faster addition of neurons to the brain than to the spinal cord is consistent with current views on how larger brains add complexity to the processing of environmental and somatic information.