Table of Contents
Journal of Biophysics
Volume 2013 (2013), Article ID 241612, 5 pages
Research Article

A Tree-Like Model for Brain Growth and Structure

1Yan Research, P.O. Box 4115, Federal Way, WA 98063, USA
2University of Illinois College of Medicine, 190 Medical Sciences Building, MC-714, 506 Mathews Avenue, Urbana, IL 61801, USA

Received 27 March 2013; Revised 7 July 2013; Accepted 1 August 2013

Academic Editor: Giuseppe Chirico

Copyright © 2013 Benjamin C. Yan and Johnson F. Yan. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.


The Flory-Stockmayer theory for the polycondensation of branched polymers, modified for finite systems beyond the gel point, is applied to the connection (synapses) of neurons, which can be considered highly branched “monomeric” units. Initially, the process is a linear growth and tree-like branching between dendrites and axons of nonself-neurons. After the gel point and at the maximum “tree” size, the tree-like model prescribes, on average, one pair of twin synapses per neuron. About 13% of neurons, “unconnected” to the maximum tree, migrate to the surface to form cortical layers. The number of synapses in each neuron may reach 10000, indicating a tremendous amount of flexible, redundant, and neuroplastic loop-forming linkages which can be preserved or pruned by experience and learning.