title: Role of refractory period in homoclinic models of neural synchronization.
abstract: We study the properties of a homoclinic model of neuron by introducing a suitable one-dimensional map. We show that the system is characterized by a response time to external signals which is a decreasing function of the signal strength, in contrast to excitable models whose response time is signal-independent. In a one-dimensional array of these systems with bidirectional coupling, we observe a sudden transition to a synchronized state at a certain value of the coupling strength. The transition occurs when the response time of a site to the signals of the adjacent sites is of the order of refractory time. Near the transition, we find an intermittent behavior due to the competition between a turbulent and a synchronized state. The observed behavior distinguishes homoclinic systems from excitable systems.
authors.affiliation: Dipartimento di fisica, Università di Firenze, via Sansone 1, 50019 Sesto Fiorentino (FI), Italy. almont@inoa.it
authors.forename: A
authors.initials: A
authors.lastname: Montina
authors.forename: C
authors.initials: C
authors.lastname: Mendoza
authors.forename: F T
authors.initials: FT
authors.lastname: Arecchi
mesh_terms: D000200:Action Potentials / Q000502:physiology; D003344:Cortical Synchronization; D008959:Models, Neurological; D009474:Neurons / Q000502:physiology*