The Effects of Code-Switching and Lexical Stress on Vowel Quality and Duration of Heritage Speakers of Spanish

The quantity of research on Heritage Speakers (HS) of Spanish phonetics has increased over the last decade, including studies on the possible effect of code-switching on Spanish phonetics. Following this line of research, the present study investigates the role of code-switching and lexical stress on Spanish HS vowel production, specifically if the introduction of English reduces the vowel quality and duration of Spanish vowels after a code-switch. Eleven Spanish HSs participated in a controlled narration task in which they were asked to read aloud texts that code-switched between English and Spanish and one text that only contained Spanish. PRAAT was used to segment the vowels and the F1 and F2 values, along with duration, were extracted. The results show that both code-switching and lexical stress significantly affect Spanish HS vowels. Code-switching and vowels in unstressed position were more centralized than the vowels in the monolingual Spanish session and vowels in stressed position, respectively; unstressed vowels were also shorter in duration than stressed vowels. These results show that the introduction of English—a language in which vowel quality and duration change between unstressed and stressed syllables—via code-switching significantly affects Spanish HS vowels, subsequently providing evidence for transient interference