Controlling Chaotic Resonance using External Feedback Signals in Neural Systems

Abstract

Stochastic resonance is a phenomenon in which the signal response of a non-linear system is enhanced by appropriate external noise. Likewise, a similar phenomenon can be caused by deterministic chaos; this is called chaotic resonance. Devices that employ stochastic resonance have been proposed for the purpose of enhancing tactile sensitivity. However, no applications of chaotic resonance have been reported so far, even though chaotic resonance exhibits a higher sensitivity than stochastic resonance. This contrast in applications could be attributed to the fact that chaotic resonance is induced by adjusting internal parameters. In many cases, especially in biological systems, these parameters are difficult to adjust. In this study, by applying our proposed reduced region of orbit method to a neural system consisting of excitatory and inhibitory neurons, we induce chaotic resonance with signal frequency dependency against weak input signals. Furthermore, the external noise exhibits effects for both diminishing and enhancing signal responses in chaotic resonance. The outcome of this study might facilitate the development of devices utilising the mechanism of chaotic resonance.

Chaos-Chaos Intermittency Synchronization Controlled by External Feedback Signals in Chua's Circuits

“…We previously reported that these characteristics are maintained under RRO feedback signals in discrete chaotic systems [38], [44], [45]. Therefore, the characteristics of chaotic resonance observed in this study are congruent with the previous findings of [19], [38], [44], [45].…”

“…It is known that, in discrete and continuous chaotic systems with CCI, the signal response in chaotic resonance is also maximized at around the attractor-merging bifurcation, and its response exhibits dependency on the input frequency [19]. We previously reported that these characteristics are maintained under RRO feedback signals in discrete chaotic systems [38], [44], [45]. Therefore, the characteristics of chaotic resonance observed in this study are congruent with the previous findings of [19], [38], [44], [45].…”

“…This separating effect was explored in our previous studies [38], [43], [44]. Furthermore, in this study, we deal with the negative RRO feedback strength in addition to the positive RRO feedback strength.…”

“…The RRO feedback method has been adopted to only discrete chaotic systems typified as the discrete cubic map and its assembly [38], [43] and discrete neural systems [44], [45]. However, in the process of applying the RRO feedback method to actual chaotic systems, development of the RRO feedback signals in continuous chaotic systems must be considered.…”

Transition of Neural Activity From the Chaotic Bipolar-Disorder State to the Periodic Healthy State Using External Feedback Signals

“…Particularly, the chaotic resonance induced by the RRO feedback method exhibits higher sensitivity than stochastic resonances induced by additive noise and are more adaptable to various types of attractor conditions (Nobukawa et al, 2019b ). Studies on chaotic resonance induced by the RRO feedback method have been applied to neural systems (Nobukawa and Shibata, 2019 ; Nobukawa et al, 2019b ). Therefore, in addition to stochastic resonance controlled by additive noise in neural systems (Enders et al, 2013 ; Kurita et al, 2013 , 2016 ; Seo et al, 2014 ), chaotic resonance controlled by RRO feedback is at the stage where biomedical applications can be considered.…”