This study considers whether listeners’ interpretation of prosodic variables, namely the use of an utterance-final rise to indicate an uptalked statement and the alignment of the starting point of that rise to indicate whether the utterance is indeed uptalk or a question, depends on socially-conditioned expectations linked to a segmental phonetic cue earlier in the utterance. The response required of participants in the experiment reported below is whether an utterance is intended as a question or as a statement, a distinction that has been linked in New Zealand English (NZE) to the difference between early and late starting points respectively for the final rise. The segmental sociophonetic cue used in the experiment as a potential indicator of social grouping is the realization of a single vowel in a word that occurs earlier in each test utterance, prior to the intonational cue. This is the realization of the SQUARE diphthong,1 which for many speakers of the same dialect is merged with the NEAR diphthong. For non-merging speakers, the SQUARE and NEAR vowels might be transcribed phonemically as /eɘ/ and /iɘ/ respectively. For merging speakers, these two centering diphthongs both have a closer starting point that is more typical of the realization of NEAR for non-merging speakers, i.e., [iɘ]. Uptalk use, the distinction between early and late rises for questions and statements and the NEAR-SQUARE merger are all linked in this language variety with younger speakers (predominantly teenagers and those in their twenties), especially females, although not all young New Zealand women regularly use uptalk or merge their NEAR and SQUARE diphthongs. The research question is whether manipulation of the vowel causes a change in listeners’ expectations about the speaker, resulting in a shift in the interpretation of the intonation. Background information on both the intonational pattern and the vowel cue will now be presented, in order to contextualize the experimental design.

Uptalk has been documented for New Zealand English (largely under the label HRT, for high-rising terminal) since the mid-1960s (Benton, 1965). Early systematic studies indicated that it was most prevalent amongst the young, and particularly young women (Bell & Johnson, 1997; Britain, 1992), and there remains a strong association of uptalk with younger speakers. An important factor for the experiment reported below is the extent of the overlap of uptalk with question intonation. Since intonational rises can also mark questions, there is a frequent lay perception that uptalk indicates a questioning nature, and that uptalkers are therefore insecure or lacking in confidence (see discussion in Warren, 2016). This association is not entirely surprising, given that it has been claimed that uptalk rises and question rises may be phonetically indistinguishable (Guy et al., 1986; Ladd, 1996; Lakoff, 1973). However, more recent research indicates emerging differences between these rise types in a number of varieties of English, with the nature of the differences dependent on variety (Warren & Fletcher, 2016). In Australian English, for instance, uptalk rises tend to start from a lower pitch, possibly as part of a fall-rise contour (Fletcher & Harrington, 2001; McGregor, 2005). Other research has suggested that question rises have earlier onsets than statement rises, in particular in NZE (Fletcher et al., 2005; Warren, 2005; Warren & Daly, 2005), South African English (Dorrington, 2010), and Southern Californian (Ritchart & Arvaniti, 2014). It should be stressed that early and late are relative concepts, and refer to the alignment of the rise onset with regard to the nuclear accent and following material, rather than in the utterance as a whole. In NZE, this alignment difference has been shown to be related to speaker age, with younger speakers more likely to distinguish between an early rise start for questions and a later start for uptalk utterances, while older speakers use later onsets for both sentence types (Fletcher et al., 2005; Warren, 2005).

A number of perceptual studies have investigated the cueing value of such differences. In one study, Fletcher and Loakes (2010) found that the most statement-like utterances in a set of rising Australian English utterances were those with a low onset, while questions were signalled more reliably by a high onset, reflecting the production data for that variety. In a small-scale study in NZE (Warren, 2005; Zwartz & Warren, 2003), participants were asked to classify variants of a single utterance. The utterance in question had a six-syllable nucleus + tail sequence (basketball stadium), and the final rise was resynthesized firstly so that its onset was temporally aligned at a range of five equally distant points from the initial accented syllable (ba-) through to the utterance-final syllable (-um), and secondly so that rises either progressed linearly towards a final high point at the end of the utterance, or involved a sharp rise followed by a high plateau. The results indicated that questions were more clearly signalled by the sharp early rise, and statements by the sharp late rise, reflecting respectively the convex and concave contours found in production data from NZE speakers (Warren, 2005).

The current study aims to build on these findings by additionally investigating whether the listeners’ perceptions of uptalk, and of early and late rises in NZE as signals of questions and statements respectively, are also dependent on whether the speaker is a likely ‘uptalker.’ As indicated above, it does so indirectly by manipulating a segmental variable that has a social distribution similar to that of uptalk, i.e., the realization of the SQUARE diphthong. In a longitudinal study of the NZE NEAR-SQUARE merger, Gordon and Maclagan (2001) examined production data based on words containing these vowels, read in sentence and word-list contexts by adolescents from the same demographic, sampled every five years. While the diphthongs were still both widely present in their first sample from 1983, they showed significant overlap in adolescent speech by 1998. The merger has been towards a closer starting point for SQUARE, i.e., a merger-by-approximation towards NEAR. In the current paper, this innovative realization of SQUARE will be given the label [iɘ], which is the transcription recommended for the NEAR diphthong in NZE by Bauer and Warren (2004). The more conservative variant will be labelled [eɘ], the transcription they give for SQUARE, although it should be noted that single labels cannot do justice to the variation that is found in both the closer and the more open realization of the diphthong. Like the use of uptalk intonation, the use of a variant of SQUARE with a closer starting point continues to be commented on in the media and in letters-to-the-editor, particularly as a possible source of ambiguity (in this case resulting in perceived homophony of words like beer and bare or cheer and chair). It also continues to be associated with the speech of younger speakers, with the diphthongs remaining unmerged for many, especially older speakers.

Based on a series of experiments involving the production and perception of NEAR and SQUARE, Warren et al. (2007) concluded that the social indexing of the merger in NZE meant that lexical items containing a diphthong with the closer starting point of [iɘ] were least likely to be identified as containing the SQUARE vowel when the speaker was perceived to be older and male. This was demonstrated in a study employing four voices (two of each sex) that were independently rated for probable speaker age. In another study Hay et al. (2006b) manipulated age through photographs and showed that perceived age of the speaker influenced identification accuracy of NEAR and SQUARE word pairs. The photographs were presented as though they were pictures of the speakers being listened to, and accuracy was greatest after photographs of older individuals, even though the same male and female speech tokens were presented after each of the male and female photographs respectively. The consequences of the merger for lexical access have also been investigated in semantic priming experiments (Warren et al., 2007; Warren et al., 2003), which showed that there was an asymmetry in the priming exhibited by young NZE-speaking participants, but that listeners were again sensitive to the age of the speaker. When the stimuli were from a younger voice, the form [ʧiɘ] primed both shout (an associate of cheer) and sit (an associate of chair), but the form [ʧeɘ] only primed sit (the associate of chair). When an older speaker was used, the priming was not asymmetrical—[ʧiɘ] primed only shout and [ʧeɘ] primed only sit.

The brief summaries above of research on uptalk and on the NEAR-SQUARE merger in NZE indicate some changes-in-progress that have been occurring over a similar timeframe, and which are similarly socially stratified. Younger speakers, particularly but not exclusively women, are more likely to use uptalk, to distinguish uptalk rises and question rises through the alignment of the start of the rise, and to have a closer starting point for the SQUARE diphthong.

The results reported above from the studies of NEAR and SQUARE conducted by Hay et al. (2006b) and by Warren et al. (2007) are part of a growing body of research that shows that social characteristics associated with speakers can affect the interpretation of phonetic information. In some of the early perceptual work in this area, Strand and Johnson (1996) found that participants’ categorization of fricatives on a [ʃ]-[s] continuum was influenced by the putative sex of the speaker as indicated by video clips with which the audio signals were aligned. Subsequently, Johnson et al. (1999) showed that listeners’ categorizations of vowels on a continuum from [ʊ] to [ʌ] were affected not only by a visually presented face (male or female), but also, in a separate experiment, by the imagined sex of the speaker (participants in one group were told that the speaker was female and asked to imagine a female speaker while doing the experiment, while the other group were told to do the same for a male speaker).

In other research, the speaker’s putative dialect origin has been shown to affect perceptual responses. Niedzielski (1999) asked participants, all residents of Detroit, to indicate which of a set of resynthesized vowels best matched a vowel in a sentence they had heard. The results showed that participants who were led to believe that the speaker was from Canada chose a different resynthesized vowel from those who were led to believe that the speaker was from Detroit, despite the fact that both groups of participants heard precisely the same sentences and resynthesized vowels. Hay et al. (2006a) asked their participants to identify which of a series of resynthesized vowels best matched an /ɪ/ target vowel. Again, the experimental manipulation was the supposed dialect origin of the speaker, but in this case this was signalled not explicitly through instructions to the participants, but by means of the appearance of the words ‘Australian’ or ‘New Zealander’ at the top of the response sheets. While the results for male participants were inconclusive, female participants were more likely to select a raised, more Australian token from the continuum when they were in the ‘Australian’ condition. In a subsequent study, Hay and Drager (2010) found that the mere presence of a stuffed toy kangaroo (indicating Australia) or kiwi (indicating New Zealand) could influence listeners’ responses.

As well as the age effects shown in the studies of NZE NEAR and SQUARE by Hay et al. (2006b) and Warren et al. (2007), Drager (2011) found that the speaker’s perceived age influenced the categorization of vowels on a DRESS-TRAP continuum in NZE, a variety which has a well-established pattern of raising of the short front vowels. However, she found this effect only for older participants, which she conjectures may be linked to their greater experience of a range of speakers from different generations as well as to their greater exposure to the progression of the sound change.

The studies reviewed above have exploited the potential social indexicality of phonetic cues and have shown that segmental phonetic perception can be affected by the perceived characteristics of the speaker (as prompted by photographs, movie clips, dialect region labels, or even stuffed toys). The current study builds on these links between speaker characteristics and phonetic properties at the segmental level, and investigates whether segmental differences can impact on the interpretation of cues at the suprasegmental level. The interaction of segmental and suprasegmental cues in linguistic indexicality has previously been explored by Levon (2007), who manipulated sibilant duration and pitch range in a read passage. Levon found that pitch range only affected judgements of the speaker on an effeminate-masculine scale when the sibilants were short, and that sibilant duration only affected such judgements when pitch range was narrow. The current study takes a different approach to the interaction of segmental and suprasegmental cues. Rather than asking participants to judge characteristics of the speaker on the basis of phonetic cues, it exploits the fact that the realization of the SQUARE vowel, the use of uptalk, and the alignment differences in statement and question pitch rises are typically co-indexical of younger speakers,2 and examines whether as a consequence variation in the segmental cue will affect the interpretation of the suprasegmental cues. That is, if a SQUARE diphthong in an utterance has an [iɘ] realization and signals a speaker who is more likely to produce uptalk, then a subsequent rising intonation is more likely to be interpreted as uptalk. In addition, if the type of speaker signalled by the [iɘ] realization of SQUARE is also the type of speaker who makes a phonetic distinction between question and statement rises, then a subsequent early rise should be more likely to signal a question and a late rise a statement, relative to a situation where the diphthong has a more conservative [eɘ] realization.

The two speech features indicated above—the realization of the SQUARE diphthong as [iɘ] or [eɘ] and the realization of a rise with an early or late onset—were manipulated on utterances with declarative word order which were then used in a forced-choice task, where participants had to select between two sentence types—question and statement. An example sentence is given in (1).

The word that has the SQUARE diphthong in this example is cared. All relevant words in the test utterances were words which would have an [eɘ] realization of the SQUARE diphthong in the speech of more conservative speakers, and for which there was no minimal pair word that differed only in having the NEAR vowel. This vowel was manipulated (see below) so that it had either the conservative [eɘ] realization or the innovative [iɘ] realization.

The rise was on the final nuclear accented word, animals, and was manipulated (see below) so that it started either at the end of the accented syllable (i.e., the first syllable) or at the beginning of the final syllable, which was also the last syllable in the utterance. All final words were three syllables long. These rise alignments are compatible with those found in the production research described above.

A further aspect of the experiment reported below that differs from the previous forced-choice studies of sentence type is that in addition to collecting response choice and reaction time, the experiment tracks mouse movements made by participants as they make their selection. The mouse-tracking technique records the (x, y) pixel coordinates of the trajectory of cursor movements on a computer screen as participants use the computer mouse to move the cursor from its starting point to a decision target. Studies using this technique have shown that details of the mouse trajectory, such as its curvature and complexity, co-vary with a range of cognitive processes involved for instance in auditory lexical decision (Spivey et al., 2005), visual lexical decision (Barca & Pezzulo, 2012, 2015), decisions as to the truth or falsity of negated sentences (Dale & Duran, 2011), memory strength (Papesh & Goldinger, 2012), the automatic activation of phonological information during visual word processing (Barca et al., 2016), and social categorization (Freeman, 2014; Freeman et al., 2008; Freeman et al., 2011). Analyzing mouse trajectories can provide additional insights into decision processes that cannot be measured simply from the outcome decision, such as the attraction strength of competing responses over time. In addition, it has been demonstrated that movement trajectories reflect the confidence of a participant’s response, with more direct trajectories to the target correlating with higher confidence scores reported by the participants after their decisions (Papesh & Goldinger, 2012).3

The experiment tests the following hypotheses, which arise from consideration of the literature reviewed above. Firstly, there will be more ‘question’ responses (which will also be faster and more direct) following early rises than following late rises. Secondly, ‘statement’ responses will be more likely (and faster and more direct) in the context of an [iɘ] realization of the SQUARE diphthong. This would be a new finding, and would indicate that a sociophonetic cue at the segmental level influences the interpretation of a potentially ambiguous cue at the suprasegmental level (i.e., whether a rise indicates a question or uptalk). Thirdly, an [iɘ] realization of SQUARE, indicating a younger speaker, will show greater compatibility with the use of early and late rises to indicate questions vs. statements respectively. This again would be a new finding, but one which is compatible with a ‘gestalt-like understanding of indexicality’ (Levon, 2007: 546).

The experiment reported in this paper was designed to test whether the nature of a segmental phonetic variable influences listeners’ interpretation of prosodic variation. The experiment exploited the co-variation, predominantly among younger speakers, of a closer articulation of the SQUARE diphthong (approximating the NEAR vowel, i.e., [iɘ]) and final statement rises (uptalk) in NZE, and in particular the recent finding that earlier rises may provide a possible means of distinguishing questions from uptalk statements (Warren, 2005; Warren & Daly, 2005; Warren & Fletcher, 2016). Therefore two aspects of prosodic variability are involved—the variable use of final rises to signal either questions or statements in the same speech community, and the variability in the alignment of the final rise that is trending towards a marker that distinguishes these sentence types. Such variability becomes informative once it can be readily disentangled, so that there is greater clarity over whether a final rise indicates a question or a statement. The current study aimed to see whether the segmental phonetic cue in the test utterances would indicate whether or not the speaker is from a group of speakers that is likely firstly to produce uptalk and secondly to distinguish uptalk from question rises through alignment difference in the rise starting point.

The predictions set out in section 2.4 received good support. In line with previous perceptual research (Zwartz & Warren, 2003), the experiment provided further evidence that early rises are more clearly associated with questions and late rises with statements. This was reflected in the analysis of the response choice data, which showed a clear effect of rise type on the proportion of question responses. Question responses after early rises were also faster and showed a more direct mouse trajectory than question responses after late rises, and trajectory reversals were more likely after late rises, indicating increased competition from the statement response in this condition.

In addition, the manipulation of the SQUARE vowel successfully shifted performance in the forced-choice response task. The slower statement responses to items containing an [eɘ] version of this vowel than to items containing an [iɘ] version is an indication that although uptalk rises from more conservative speakers are not ruled out, they are less expected. The mouse-tracking data for question responses made after a trajectory reversal show that there is less competition from the statement response for an early rise after the [iɘ] realization of SQUARE than for the same rise after the [eɘ] realization. The trajectories also show that in the context of the [iɘ] realization there is less competition from the statement response when the rise is early than when it is late. These findings of significant results in the mouse-tracking data, particularly in the absence of significant differences in overall response choice, support the value of the technique in adding a more qualitative aspect to the interpretation of participants’ responses. In particular, these trajectory reversal data linked to the MD measure allow us to say more about the competition effects that exist between alternative response choices.

The results of this study indicate that variability in intonational rise alignment in NZE is meaningful, and is more closely tied to certain speaker groups than to others. Listener performance in the experiment reflects the parallel development in this variety of a segment-level merger and changes in the use and shape of an intonation pattern. The vowel merger has been able to happen largely because the consequences are not extreme—although letters to newspaper editors might suggest otherwise (e.g., complaints about hearing of people “crossing on the Cook Strait ‘Fairy’ and flying ‘Ear’ New Zealand” [Bravery, 2001]), confusion between words with NEAR or SQUARE tokens is not frequent, partly because the vowel sounds are relatively rare (17th and 18th most frequent out of 20 English vowels, Gimson, 1963), but also because there are few relevant minimal pairs, and because utterance contexts usually serve to disambiguate, just as they do for other homophones. Nevertheless, the merger is still strongly age-graded, and so the use of the [iɘ] or [eɘ] variant of the SQUARE vowel has potential as a marker of social grouping.

On the other hand, the prosodic variability considered here has the potential to cause confusion between two radically different sentence types—questions and statements. This is reflected again in complaints from the public, but also in the frequent definition of uptalk using terms such as ‘question-like intonation on a declarative utterance.’ Such a definition is problematic on a number of counts. The notion of ‘question’ is ambiguous between function and form, and the belief that there is any single type of ‘question intonation’ is misplaced, as is the assumption that questions have to have rising intonation. Even if we accept that ‘question-like intonation’ stands for the type of rising intonation often found on yes-no questions, there is lack of agreement about whether that type of rising intonation is identical or even similar to uptalk. Some of this disagreement may result from the presence of different styles and uses of uptalk in different English varieties (Warren, 2016). It is worth remembering also that different varieties may have reached different stages in the development and use of uptalk, with some varieties (e.g., NZE) beginning to show novel distinctions, while others (such as British English, Shobbrook & House, 2003) do not.

Ladd (2008: 126) acknowledges that uptalk and question rises may differ, but that “the differences are subtle, and arguably gradient,” and that it may be plausible to “analyse HRT statements as having the same phonological representations as high-rising question contours.” The results of the current study show that the ‘arguably gradient’ distinction between early and late rise in NZE does have the potential to signal a distinction in meaning, and that uptalk and question contours may have different phonological representations. As pointed out by House (2006), the development of a new phonological distinction is a natural resolution of a potentially confusing situation in which one pattern can have multiple functions. Note though that other factors may make such a split unlikely to happen precipitously. As Guy et al. (1986) pointed out in their discussion of Australian English, even without a phonetic difference between uptalk rises and question rises, ambiguity is unlikely, as contexts will clarify the intended meaning. For instance, true questions usually include some anaphoric reference to a previous utterance, and will usually be at the end of a turn, while uptalk tends to provide new information, with the speaker typically continuing to hold the floor. “If these clear contextual and textual differences were not sufficient to disambiguate between the two meanings, we might expect structural change to occur: For example, phonetic differentiation of the contours or disuse of the contour for one of the meanings” (Guy et al., 1986: 27). It may be that recent phonetic differences between uptalk and question intonation that have been noted for Australian and New Zealand English indicate that a level of potential confusion has been reached that requires such differentiation.

The additional file for this article can be found as follows: