Constructive effects of diversity in a multi-neuron model of the homeostatic regulation of the sleep-wake cycle

As an instance of diversity-induced resonance and of the constructive role
of heterogeneity in complex systems, here we study a generalized version of
a physiologically-motivated sleep-wake cycle model taking into account the
role of orexin [M. Patriarca, E. Hernandez-Garcia, R. Toral, S. Postnova, H.
A. Braun, PLoS Comput. Biol. 8 (2012) e1002650; S. Postnova, K. Voigt
H. A. Braun, J. Biol. Rhythms 24 (2009) 523]. With respect to the versions
of the model studied previously, here we consider systems containing both a
set of orexin neurons - responsible for the production of orexin - and a set
of glutaminergic neurons - representing mental activity or sleep depending
on their firing or silent state, respectively - within some basic network
topologies. The neurons of one or both types are diversified and it is shown
how the interplay between the heterogeneous constituent units produces as
an emergent effect the recovering or improving of the sleep-wake cycle. At a
general level, the results obtained suggest that also systems with a dynamics
driven by a homeostatic mechanism, with a time scale much longer than that
of the constituent excitable units, may present diversity-induced resonance.