It has been previously reported that changes to the fundamental frequency contour of vowels influences their identification [e.g., H. Traunmuller, J. Acoust. Soc. Am. 69, 1465–1475 (1981)]. Similar changes in vowel identification have been demonstrated for some listeners when the F0 contour of a dysarthric speaker has been modified (e.g., flattened or enhanced) [Bunton (2004)]. These listeners appear to rely on F0−F1 space for identification of vowel height; this strategy is consistent with a perceptual model of vowel recognition described by A. Syrdal and H. Gopal [J. Acoust. Soc. Am. 79, 1086–1100 (1986)]. Other listeners, however, appear to utilize different acoustic cues to identify a given vowel. This study focused on defining those perceptual strategies. Multi-dimensional plots of acoustic cues likely to influence vowel perception are used to illustrate perceptual strategies that may have been used by these listeners for identification of vowels in the speech of individuals with dysarthria associated with Parkinson disease. [Work supported by NIH R03 DC005902.]