Interactions of Intensity Glides and Frequency Glissandos

The influence of positive intensity glides is investigated on static and both rising and falling contour tones. After determining the glissando threshold by the method of discrimination, it is found that a positive or negative intensity glide associated with a static tone is perceived as a glissando in the same direction and above the threshold. A negative intensity glide, however, associated with a rising or falling glissando, hinders the perception whereas a positive glide associated with a glissando improves its perception and lowers the threshold. An effect of intensity glides on the pitch configuration is noted; a positive glide associated with a rising glissando causes a concave tone to be perceived, whereas associated with a falling one it causes a convex tone to be perceived. A model to explain this interaction is proposed based on the temporal concordance of the pitch point and the loudness point, and the implications of these results for prosodic studies are examined.