Department of Neurology, Otto-von-Guericke University, 39120, Magdeburg, Germany.
Center for Behavioral Brain Sciences, 39120, Magdeburg, Germany.
Sci Rep. 2020 Apr 14;10(1):6419. doi: 10.1038/s41598-020-63332-w.
It has been demonstrated that, while otherwise detrimental, noise can improve sensory perception under optimal conditions. The mechanism underlying this improvement is stochastic resonance. An inverted U-shaped relationship between noise level and task performance is considered as the signature of stochastic resonance. Previous studies have proposed the existence of stochastic resonance also in the human auditory system. However, the reported beneficial effects of noise are small, based on a small sample, and do not confirm the proposed inverted U-shaped function. Here, we investigated in two separate studies whether stochastic resonance may be present in the human auditory system by applying noise of different levels, either acoustically or electrically via transcranial random noise stimulation, while participants had to detect acoustic stimuli adjusted to their individual hearing threshold. We find no evidence for behaviorally relevant effects of stochastic resonance. Although detection rate for near-threshold acoustic stimuli appears to vary in an inverted U-shaped manner for some subjects, it varies in a U-shaped manner or in other manners for other subjects. Our results show that subjects do not benefit from noise, irrespective of its modality. In conclusion, our results question the existence of stochastic resonance in the human auditory system.
已经证明，在最佳条件下，噪声虽然有害，但可以改善感官知觉。这种改善的机制是随机共振。噪声水平与任务表现之间的倒 U 形关系被认为是随机共振的特征。先前的研究已经提出，随机共振也存在于人类听觉系统中。然而，基于小样本，报告的噪声的有益效果很小，并且不能证实所提出的倒 U 形函数。在这里，我们通过应用不同水平的噪声（无论是通过听觉还是通过经颅随机噪声刺激）来研究人类听觉系统中是否存在随机共振，而参与者必须检测调整到其个体听力阈值的声刺激。我们没有发现随机共振具有行为相关影响的证据。尽管对于一些受试者，接近阈值的声刺激的检测率似乎以倒 U 形方式变化，但对于其他受试者，其变化呈 U 形或其他方式。我们的结果表明，无论噪声的模态如何，受试者都不会受益。总之，我们的结果质疑随机共振在人类听觉系统中的存在。
