Palatalization has been broadly characterized as involving tongue fronting, tongue raising, and spirantization Bateman, 2011. While its acoustic and phonological effects are well documented, the articulatory realization, particularly the tongue target of palatalized /p/ in Japanese, remains underexplored. This study investigates the articulation of palatalized /p, t, s, k/ in /paCja/ sequences by native speakers of Japanese using ultrasound tongue imaging. Preliminary results show that the tongue gesture during palatalized /p/ approximates the hard palate as expected. Palatalized /p/ is sometimes described as a consonant cluster /pj/ in Japanese; however, gestural timing analysis revealed that the C-center effect, commonly associated with consonant clusters, was not consistently observed across speakers. Furthermore, the tongue body gesture for /j/ seemed to have substantial temporal overlap with the lip gesture, as the /j/ gesture often began before the /p/ closure. This high degree of overlap suggests an in-phase coordination between /p/ and /j/, rather than an anti-phase pattern typical of clusters. These findings support the view that Japanese may employ a specific gestural timing system to maintain moraic structure and that some speakers may treat palatalized /p/ as a single coordinated unit rather than a true consonant cluster.
Mizoguchi et al. (Wed,) studied this question.