Critical phenomena at a firstorder phase transition in a lattice of glow lamps: Experimental findings and analogy to neural activity
Abstract
Networks of nonlinear electronic oscillators have shown potential as physical models of neural dynamics. However, two properties of brain activity, namely, criticality and metastability, remain underinvestigated with this approach. Here, we present a simple circuit that exhibits both phenomena. The apparatus consists of a twodimensional square lattice of capacitively coupled glow (neon) lamps. The dynamics of lamp breakdown (flash) events are controlled by a DC voltage globally connected to all nodes via fixed resistors. Depending on this parameter, two phases having distinct event rate and degree of spatiotemporal order are observed. The transition between them is hysteretic, thus a firstorder one, and it is possible to enter a metastability region, wherein, approaching a spinodal point, critical phenomena emerge. Avalanches of events occur according to powerlaw distributions having exponents ≈3/2 for size and ≈2 for duration, and fractal structure is evident as powerlaw scaling of the Fano factor. These critical exponents overlap observations in biological neural networks; hence, this circuit may have value as building block to realize corresponding physical models.
 Authors:
 Center for Mind/Brain Sciences, University of Trento, 38123 Mattarello (Italy)
 (Poland)
 Department of Physics “E. Pancini,” University of Naples “Federico II,” Napoli (Italy)
 (Italy)
 INFN Gr. Coll. Salerno, Unità di Napoli, Napoli (Italy)
 Publication Date:
 OSTI Identifier:
 22596641
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Chaos (Woodbury, N. Y.); Journal Volume: 26; Journal Issue: 7; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
 Country of Publication:
 United States
 Language:
 English
 Subject:
 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; 97 MATHEMATICAL METHODS AND COMPUTING; FANO FACTOR; LIGHT BULBS; NONLINEAR PROBLEMS; OSCILLATORS; RESISTORS; TETRAGONAL LATTICES
Citation Formats
Minati, Ludovico, Email: lminati@ieee.org, Email: ludovico.minati@unitn.it, Email: ludovico.minati@ifj.edu, Complex Systems Theory Department, Institute of Nuclear Physics, Polish Academy of Sciences, Kraków, Candia, Antonio de, INFN Gr. Coll. Salerno, Unità di Napoli, Napoli, Scarpetta, Silvia, and Department of Physics “E.R.Caianiello,” University of Salerno, Napoli. Critical phenomena at a firstorder phase transition in a lattice of glow lamps: Experimental findings and analogy to neural activity. United States: N. p., 2016.
Web. doi:10.1063/1.4954879.
Minati, Ludovico, Email: lminati@ieee.org, Email: ludovico.minati@unitn.it, Email: ludovico.minati@ifj.edu, Complex Systems Theory Department, Institute of Nuclear Physics, Polish Academy of Sciences, Kraków, Candia, Antonio de, INFN Gr. Coll. Salerno, Unità di Napoli, Napoli, Scarpetta, Silvia, & Department of Physics “E.R.Caianiello,” University of Salerno, Napoli. Critical phenomena at a firstorder phase transition in a lattice of glow lamps: Experimental findings and analogy to neural activity. United States. doi:10.1063/1.4954879.
Minati, Ludovico, Email: lminati@ieee.org, Email: ludovico.minati@unitn.it, Email: ludovico.minati@ifj.edu, Complex Systems Theory Department, Institute of Nuclear Physics, Polish Academy of Sciences, Kraków, Candia, Antonio de, INFN Gr. Coll. Salerno, Unità di Napoli, Napoli, Scarpetta, Silvia, and Department of Physics “E.R.Caianiello,” University of Salerno, Napoli. 2016.
"Critical phenomena at a firstorder phase transition in a lattice of glow lamps: Experimental findings and analogy to neural activity". United States.
doi:10.1063/1.4954879.
@article{osti_22596641,
title = {Critical phenomena at a firstorder phase transition in a lattice of glow lamps: Experimental findings and analogy to neural activity},
author = {Minati, Ludovico, Email: lminati@ieee.org, Email: ludovico.minati@unitn.it, Email: ludovico.minati@ifj.edu and Complex Systems Theory Department, Institute of Nuclear Physics, Polish Academy of Sciences, Kraków and Candia, Antonio de and INFN Gr. Coll. Salerno, Unità di Napoli, Napoli and Scarpetta, Silvia and Department of Physics “E.R.Caianiello,” University of Salerno, Napoli},
abstractNote = {Networks of nonlinear electronic oscillators have shown potential as physical models of neural dynamics. However, two properties of brain activity, namely, criticality and metastability, remain underinvestigated with this approach. Here, we present a simple circuit that exhibits both phenomena. The apparatus consists of a twodimensional square lattice of capacitively coupled glow (neon) lamps. The dynamics of lamp breakdown (flash) events are controlled by a DC voltage globally connected to all nodes via fixed resistors. Depending on this parameter, two phases having distinct event rate and degree of spatiotemporal order are observed. The transition between them is hysteretic, thus a firstorder one, and it is possible to enter a metastability region, wherein, approaching a spinodal point, critical phenomena emerge. Avalanches of events occur according to powerlaw distributions having exponents ≈3/2 for size and ≈2 for duration, and fractal structure is evident as powerlaw scaling of the Fano factor. These critical exponents overlap observations in biological neural networks; hence, this circuit may have value as building block to realize corresponding physical models.},
doi = {10.1063/1.4954879},
journal = {Chaos (Woodbury, N. Y.)},
number = 7,
volume = 26,
place = {United States},
year = 2016,
month = 7
}

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