title: Growth cone pathfinding: a competition between deterministic and stochastic events.
abstract: BACKGROUND
  Growth cone migratory patterns show evidence of both deterministic and stochastic search modes.
  
  
  RESULTS
  We quantitatively examine how these two different migration modes affect the growth cone's pathfinding response, by simulating growth cone contact with a repulsive cue and measuring the resultant turn angle. We develop a dimensionless number, we call the determinism ratio Psi, to define the ratio of deterministic to stochastic influences driving the growth cone's migration in response to an external guidance cue. We find that the growth cone can exhibit three distinct types of turning behaviors depending on the magnitude of Psi.
  
  
  CONCLUSIONS
  We conclude, within the context of these in silico studies, that only when deterministic and stochastic migration factors are in balance (i.e. Psi ~ 1) can the growth cone respond constructively to guidance cues.
authors.affiliation: Department of Biomedical Engineering, Rutgers University, Piscataway, NJ, 08854, USA. smaskery@soemail.rutgers.edu
authors.forename: Susan M
authors.initials: SM
authors.lastname: Maskery
authors.forename: Helen M
authors.initials: HM
authors.lastname: Buettner
authors.forename: Troy
authors.initials: T
authors.lastname: Shinbrot
mesh_terms: D000465:Algorithms; D003198:Computer Simulation; D005727:Ganglia, Spinal / Q000166:cytology; D020439:Growth Cones / Q000502:physiology*; D008959:Models, Neurological; D009475:Neurons, Afferent / Q000502:physiology / Q000648:ultrastructure; D013269:Stochastic Processes