Dendritic spines and linear networks

J Physiol Paris. Jul-Nov 2004;98(4-6):479-86. doi: 10.1016/j.jphysparis.2005.09.014. Epub 2005 Nov 23.


The function of the cortical microcircuitry is still mysterious. Using a bottom-up analysis based on the biophysics and connectivity of cortical neurons, we propose the hypothesis that the neocortex is essentially a linear integrator of inputs. Dendritic spines would slow the neuron and contribute to linearize input summation. Since excitatory axons are relatively straight, they appeared designed to help disperse information to a large number of recipient neurons, generating a distributed circuit. A linear summation regime will ensure the full benefit of a distributed connectivity matrix. Linear integration could also help the neocortex decode the sensory world and may have additional computational advantages. In this view, spines would be the anatomical signature of linear networks.

Publication types

  • Research Support, Non-U.S. Gov't
  • Review

MeSH terms

  • Action Potentials / physiology
  • Animals
  • Axons / physiology
  • Cerebral Cortex / physiology
  • Cluster Analysis
  • Data Interpretation, Statistical
  • Dendritic Spines / physiology*
  • Humans
  • Linear Models
  • Models, Neurological*
  • Nerve Net / physiology*
  • Neurons, Afferent / physiology
  • Pyramidal Cells / physiology