Noise-enhanced transmission efficacy of aperiodic signals in nonlinear systems

Aperiodic stochastic resonance proposed by Collins et al 1,2 describes the noiseenhanced effect in neural excitable systems for transmitting aperiodic (arbitrary) signals. This notion emphasizes the shape matching between the input and the output signals in biological information processing, and also breaks the limitation of stochastic resonance systems with periodic inputs. In order to characterize the information-carrying signal through the nonlinear system, such measures as the cross-correlation coefficient 1–3, the mutual information , the Kullback entropy 5 and the channel capacity 6 are utilized. Later, the notion of aperiodic stochastic resonance, as an outstanding extension of conventional stochastic resonance, inspired its investigation in the area of biological information processing 7–14. However, some interesting questions have not yet been touched upon. For instance, which type of