How prosody is both mandatory and optional
Speech signals originate as a sequence of linguistic units selected by speakers,but these units are necessarily realised in the suprasegmental dimensions oftime, frequency and amplitude. For this reason prosodic structure has beenviewed as a mandatory target of language processing by both speakers andlisteners. In apparent contradiction, however, prosody has also been argued tobe ancillary rather than core linguistic structure, making processing of prosodicstructure essentially optional. In the present tribute to one of the luminaries ofprosodic research for the past quarter century, we review evidence from studiesof the processing of lexical stress and focal accent which reconciles these viewsand shows that both claims are, each in their own way, fully true.