Individual variability in the attention-orienting function of edge tones in German: A pupillometry study

Using a changing-state oddball paradigm, in which auditory sequences of sequentially ordered ascending numbers (standards; e.g., 21 22 23 24 25 26...) are occasionally interspersed with an out-of-the-sequence number (deviant; e.g., 25 in 21 22 23 25 26...), we investigate the role of individual variability in the effect of rising intonation on attention orienting in German. Standard numbers featured a shallow fall in pitch, referred to as neutral intonation, as it is a pattern commonly found on non-final items in a sequence, while deviant numbers were produced with either the same neutral intonation, or rising or falling intonation. The difference in pitch contour was a reflex of different edge tone combinations, the pitch accent being the same in all three conditions. Participants’ cognitive variability was measured on the basis of processing speed, inhibitory ability, and working memory capacity (WMC), using odd-man-out, flanker, and digit span tasks, respectively. Results show that individuals with better inhibitory skills, showed sustained pupil dilation response (PDRs) to rising deviants, as compared with neutral and falling ones, with no difference between the latter two ([rise] > [fall = neutral]). In contrast, individuals with weaker inhibitory skills exhibited sustained PDRs to both rising and falling intonation, but not to the baseline neutral ([rise = fall] > [neutral]). These findings highlight individual differences in the allocation of attentional resources and suggest that phrase final pitch movements effectively capture attention across cognitive profiles. This supports the view that intonational tones at the edges of constituents can serve as attention-orienting devices, with implications for theories of intonation and auditory attention.