2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/19221We examine a simple biologically-motivated neural network, the three-layer version of the Chialvo-Bak `minibrain' [Neurosci. 90 (1999) 1137], and present numerical results which indicate that a non-equilibrium phase transition between ordered and disordered phases occurs subject to the tuning of a control parameter. Scale-free behaviour is observed at the critical point. Notably, the transition here is due solely to network geometry and not any noise factor. The phase of the network is thus a design parameter which can be tuned. The phases are determined by differing levels of interference between active paths in the network and the consequent accidental destruction of good paths.10 pages, 5 figures. Version accepted for publication in Physica ADisordered Systems and Neural NetworksAdaptation and Self-Organizing SystemsBiological PhysicsNeurons and Cognitiontext