Figure 4.
Psychometric functions obtained for the formant continuum stimuli in the spectral speech categorization test. The continuum steps numbers 1 through 8 represent gradual changes from /ba/ to /da/. Dashed lines reflect data from two CI listeners (CI01 and CI14) who demonstrated especially poor perception along the continuum, labeling most stimuli as /da/. The solid line for the CI listener group excludes those two listeners.
