Fig. 1

Performance on voice (V) and nonvoice (NV) processing. This figure illustrates the performance of typically developed (TD) subjects, participants with the chromosome 15 deletion (DEL) and uniparental disomy (UPD) in terms of their hit rates (a) and reaction times (b) for Voice (V) or Non-voice (NV) stimuli. Concerning hit rates, participants with PWS, especially UPD participants, were deficient in the recognition of voices and non-voices. This deficit was slightly weaker for voices than for non-voices in both genetic subgroups. To avoid clutter, only significant effects for voices are indicated in the figure as (*). The deficit in hit rates was accompanied by significantly longer reaction times with no difference between voices and non-voices