感觉系统检测弱信号的随机共振现象  

Stochastic Resonance in Weak Signal Detection by Sensory Systems.

作　　者：刘军[1] 李光[1] 刘世龙[1] 陈裕泉[1] 

机构地区：[1]浙江大学生物医学工程及仪器科学学院生物医学工程系,浙江杭州310027

出　　处：《航天医学与医学工程》2004年第5期360-364,共5页Space Medicine & Medical Engineering

摘　　要：目的通过信号检测理论和心理物理学实验来研究人体感觉系统中噪声增强感觉的现象。方法感觉系统可用一个由接收器部分和分类器部分组成的阈值检测器来模拟。其中 ,接收器部分不再被看作是线性单元或是单个非线性单元 ,而是被看作是由多个MacCulloch Pitts神经元构成的加性网络。使用百分比正确率和信号可检测度这 2个评价指标来模拟新模型的性能。采用心理物理学实验方法中的单择一的强迫选择法和二择一的强迫选择法来验证模拟结果。结果模拟结果显示 2个评价指标都表现出随机共振现象 ,实验在定性上说明了理论模型的正确性。结论感觉系统是通过随机共振现象来利用噪声增强感觉的 。Objective To study the stochastic resonance phenomenon in biological sensory systems through signal detection theories and psychophysical experiments. Method Sensory system is considered as threshold detectors including the receiver part and the classifier part. Compared with conventional models regarding the receiver part of 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. Result The simulation results showed that the relevant indices of the percent correct measure and the detectability of signal both exhibit stochastic resonance behaviours. 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. Conclusion This work gives a proof that stochastic resonance is not only an epiphenomenon in sensory systems.

关 键 词：随机共振 信号检测 心理物理学 MacCulloch—Pitts 神经元网络 

分 类 号：R338[医药卫生—人体生理学] R319[医药卫生—基础医学]