Selective adaptation of vowels

Two experiments investigating the selective adaptation of vowels examined changes in listeners’ identification functions for the vowel continuum i-I-∈] as a function of the adapting stimulus. In Experiment I, the adapting stimuli were i], I], and ∈]. Both the i] and ∈] stimuli produced significant shifts in the neighboringand distant phonetic boundaries, whereas I] did not result in any adaptation effects. In order to explore the phonetic nature of feature adaptation in vowels, a second experiment was conducted using the adapting stimuli gig] and g ∈ g], which differed acoustically from the i] and ∈] vowels on the identification continuum. Only gig] yielded reliable adaptation effects. The results of these experiments were interpreted as suggesting arelative rather than a stableauditory mode of feature analysis in vowels and a possibly more complex auditory feature analysis for the vowel i].