Aspects of consonant cluster mutations: the case of /sr/ sequences in Italian

Sequences of lingual fricatives + apical trills involve conflicting configurations of the tongue-tip/dorsum and create the conditions for assimilatory changes leading to the weakening or loss of the lingual fricative before the trill. In Italian, unlike other Romance languages, no assimilation of /s/ to /r/ has been reported. The aim of this paper is to explore the phonetic characteristics of /sr/ clusters in Italian and understand what prevents the assimilation of the lingual fricative to the apical trill. The hypothesis tested is that this may be due to the insertion of an epenthetic consonant or vowel at the release of the fricative impeding the gestural overlap between the fricative and the trill. To this purpose, the target sequences /VzrV/, /Vz(#)rV/, /Vs##rV/, and the control sequences /Vr:V/, /Vr##rV/, /V#zdrV/, /V#strV/ were embedded in real words and read by Northern and Southern Italian speakers. The acoustic characteristics of the segments in the sequences were measured. The results show that the fricative is maintained in Italian /sr/ sequences, and that an epenthetic vowel occurs after the obstruent in the test and control sequences. In addition, in the /sr/ sequences, the realization of the rhotic as a tap followed by a burst or period of frication may provide the cues for an epenthetic voiced stop at the transition between the /s/ and the /r/. The data also provide evidence for the presence of an actual stop occurring between /s/ and /r/, which parallels historical patterns from Latin into Romance.