Phonetic recalibration does not depend on working memory

Abstract

Listeners use lipread information to adjust the phonetic boundary between two speech categories (phonetic recalibration, Bertelson et al. 2003). Here, we examined phonetic recalibration while listeners were engaged in a visuospatial or verbal memory working memory task under different memory load conditions. Phonetic recalibration was--like selective speech adaptation--not affected by a concurrent verbal or visuospatial memory task. This result indicates that phonetic recalibration is a low-level process not critically depending on processes used in verbal- or visuospatial working memory.

Fig. 1

Schematic overview of an exposure-test block in the low-load memory condition. In the visuospatial memory task (a), the motion path of a dot had to be remembered during the audiovisual exposure—auditory-only test phase. The memory probe immediately followed the final test token. In the verbal task (b), three letters had to be remembered

Fig. 2

Proportion of ‘b’-responses after exposure to A?Vb and A?Vd (upper panels) and AbVb and AdVd (lower panels) for the single and dual tasks. Data are averaged over memory load. Error bars represent one standard error of the mean