[Instabilities in tactile, visual and auditory sense--application of stochastic catastrophe model]

As a fundamental study on management of the working environment, instabilities in tactile, visual and auditory sense are discussed. The effects of localized vibration on the ability to discriminate the surface roughness are analyzed by means of the stochastic cusp catastrophe model. Also, bistable perception of the ambiguous man/girl figure is modelled in the same way. Furthermore, the instable phenomenon of a pure tone when heard under the masking noise is pointed out and analyzed by the catastrophe model.