[Stochastic resonance in weak signal detection by sensory systems].
OBJECTIVE
To study the stochastic resonance phenomenon in biological sensory systems through signal detection theories and psychophysical experiments.


METHODS
Sensory system is considered as threshold detectors including the receiver part and the classifier part. Compared with conventional models regarding the receiver part of the sensory system as a linear or single non-linear system, a summing network constructed by MacCulloch-Pitts neurons was provided in our model to simulate the receiver part.


RESULTS
The simulation results showed that the relevant indices of the percent correct measure and the detectability of signal both exhibit stochastic resonance behaviors. Psychophysical experiments were carried out through both 1IFC (one interval forced choice) and 2IFC (two interval alternative forced choice) methods. The experimental results qualitatively verified the considerations in accordance with the theoretical model.


CONCLUSIONS
This work gives a proof that stochastic resonance is not only an epiphenomenon in sensory systems.
Liu
Jun
J
College of Biomedical Engineering and Instrument Science, Zhejiang University, Hangzhou, China. mailtoliujun@yahoo.com.cn
Li
Guang
G
Liu
Shi-long
SL
Chen
Yu-quan
YQ
D008959:Models, Neurological; D016571:Neural Networks, Computer; D011601:Psychophysics; D012684:Sensory Thresholds; D017603:Signal Detection, Psychological; D013269:Stochastic Processes