While the arbitrary relationship between linguistic form and function is a founding principle of linguistics as a broader field (Saussure, 1916), there has long been interest in cases of apparent non-arbitrary meaning in language, and arguably a resurgence of interest in the last decade (e.g., Eckert, 2010; D’Onofrio, 2014; Podesva, Callier, Voigt, & Hilton, 2015; Pratt, 2018; Salffner, 2017; Kawahara, Noto, & Kumagai, 2018; Wong & Kang, 2019). The most iconic example of non-arbitrary meaning is codified in Ohala’s Frequency Code (1984, 1994; see also Morton, 1977): Noises made by smaller things have higher frequencies than noises made by larger things, and through this fact of the physical world, higher pitch non-arbitrarily signals smallness and attributes associated with smallness, including deference and politeness (Ohala, 1994, p. 327). Critically, because the relationship between the form (high pitch) and the meaning (i.e., deference) is non-arbitrary, it is framed as universal: “there is something common to all human speakers, at all stages in history” (Ohala, p. 326). ln fact, Ohala’s argument for the non-arbitrary relationship largely relies on “high cross-language incidence” (p. 326).

Many studies have confirmed an association between pitch and perceived size (e.g., Apple, Streeter, & Krauss, 1979; van Bezooijen, 1995; van Dommelen & Moxness, 1995; Feinberg, Jones, Little, Burt, & Perrett, 2005; Puts, Gaulin, & Verdolini, 2006; Drager, Hardeman-Guthrie, Schutz, & Chik, 2021). This is the relationship central to the Frequency Code, and the relationship which Ohala (1994, pp. 336–342) even posits shaped the evolutional development of (relative) sexual dimorphism of larynx size and position in humans and other species. However, the evidence for a relationship between higher pitch and “social” meanings, like more polite speech, is messier. Some studies have found an association between higher pitch and politeness (e.g. Brown & Levinson, 1987, p. 267; Loveday, 1981; Ohara, 2000; Idemaru, Winter, Brown, & Oh, 2020), some have found no evidence of a clear relationship (Tsurutani & Shi, 2018; Idemaru et al., 2020), and increasingly, some have found evidence of the opposite relationship: Low pitch is associated with more polite speech (Winter & Grawunder, 2012; Shin, 2005). In a meta-analysis of seven studies using the same production task in different languages (from four language families), Winter, Oh, Hübscher, Idemaru, Brown, Prieto, and Grawunder (2021) found that in none of the languages included did they see people raise their pitch to be polite, and in fact, in five of the languages people significantly lowered their pitch in more polite situations.

The politeness paradigm used in those seven studies comes from Winter and Grawunder’s (2012) study on Korean. Student participants in that study were recorded responding to imagined situations where they were interacting with a friend, or with an authority figure like their professor (the “polite” condition). In Korean, these different contexts would trigger essentially obligatory use of two different grammatical registers that primarily affect verb endings: contaymal (존댓말), an honorific register typically used with seniors and unfamiliars (collectively referred to as wi salam, or “above people”), and panmal (반말), literally “half speech,” used with juniors and intimates (alay salam, or “below people”) (Kim, 2011). This task reflects a specific sort of implementation of politeness, one centered on formality and discernment.

To explain how listeners could develop an association between lower pitch and more polite speech in some of these studies, Winter et al. (2021) argue that lower pitch can represent “damped down” (p. 8) emotions, a sign of restraint that is appropriate for formal situations. In support of this interpretation, other work in Korean suggests that contaymal is associated with restricted physical movements (Brown & Winter, 2018), and a correlation between higher pitch and increased physical movement has also been found in U.S. English (Voigt, Podesva, & Jurafsky, 2014). This association between pitch and emotion can also be understood to be non-arbitrary, rooted in the physical world: Work on vocal emotion has emphasized the impact that emotionally-induced physiological reactions can have on the vocal folds, with greater emotional activation resulting in higher mean f0 (Scherer, 1986; Laukka, Juslin, & Bresin, 2005). While the relationship between vocal fold activation and valence is independent (i.e., both positive and negative vocalizations will have higher f0 if they are energetic), there is also evidence of an association between sadness and lower f0, and happiness (or smiling) and higher f0 (Juslin & Laukka, 2003; Pell, 2001; Podesva et al., 2015; see also Ohala, 1994), presumably through associations with emotional activation.

Winter and colleagues do not argue that this observed association between low pitch and politeness invalidates the Frequency Code, as many studies do find a relationship between politeness and high pitch. Rather, they underscore the “pluripotentiality”1 of pitch as an iconic marker: Lower pitch can be associated with larger size non-arbitrarily, but it also has other non-arbitrary associations (Gussenhoven, 2002, 2016; see also Eckert, 2019, p. 768).

Non-arbitrary meanings then, are not just the logical and necessary outcome of a relationship between a linguistic form and a physical property or speaker type, but critically require the noticing and interpretation of that potential relationship (Peirce, 1903, p. 273). Which relationships are likely to be noticed is entrenched in not only significant cultural but also interactional context (Gal & Irvine, 2019, pp. 97–101; D’Onofrio & Eckert, 2021, p. 35; Winter et al., 2021, p. 8). This distinction between a correlation existing and a correlation being noticed has obvious parallels with the concept of orders of indexicality. Using terms from Silverstein (2003), we can call patterns that happen to co-exist between linguistic forms and contexts first-order indexicality, and relationships that build on these associations n+ orders of indexicality. The relationship between each order is centered on evocation, and “something can evoke other things in the world with a flexibility limited only by common ground” (Eckert, 2019, p. 754). In regard to iconic meanings, Eckert has argued that “orders of indexicality can start with the iconic association of sound and human qualities and move to categories of speakers based on the social associations with those qualities” (p. 763). In this understanding, the physical fact that smaller things typically have higher pitch is a first-order indexicality, the interpretation of higher pitch as meaning smallness is a second-order indexicality, the interpretation of higher pitch as meaning that something is submissive (along with the practice of then using higher pitch to sound submissive) is a higher order indexicality,2 and the interpretation of higher pitch as meaning that someone is polite is a higher order still, etc.

When we call different meanings of high/low pitch pluripotential then, we could be talking about potentials for meaning at the second-order of indexicality—the potential to notice the first-order relationships between high pitch and small size, or high pitch and vocal emotion—or we could be talking about potential at higher orders. So, when we find a lack of a relationship between things like high pitch and politeness, it could be because listeners don’t hear high pitch as small, or because they do hear high pitch as small, but that it is irrelevant for their conception of politeness. When it comes to the Frequency Code, there is already evidence that cultural differences are driven by differences at higher levels of indexicality. Van Bezooijen (1995) explored potential causes for larger gendered pitch differences in speakers of Japanese versus Dutch. Using a matched-guise study, she showed that while listeners in both countries heard female talkers with higher vocal pitch as smaller, only Japanese listeners rated such talkers as more attractive. She also asked participants to rate how important physical size and strength were to their definition of an “ideal man” and “ideal woman,” and it was found that Japanese participants reported larger differences than Dutch participants. These results suggest that cross-cultural differences in gender and pitch and attractiveness were not being driven by a lack of noticing a first-order relationship between pitch and size, but rather a difference in interpreting higher order relationship between size and gendered desirability.

It is reasonable to posit then that conflicting patterns surrounding pitch and politeness are similarly centered on differences in politeness, not in lower-order associations between pitch and size. These politeness differences could be at the cultural level, and indeed, a large body of politeness research has focused on cross-linguistic differences in conceptualizations of politeness (e.g., Brown & Levinson, 1987, pp. 244-249; Watts, 2003). Critically for the current study, these differences in politeness have implications for the significance and interpretation of attributes like deference, friendliness, or seriousness (Ide, Hill, Carnes, Ogino, & Kawasaki, 1993; Lakoff, 1973, p. 298; Hill, Ide, Ikuta, Kawasaki, & Ogino, 1986 that can be linked through lower indexical orders to pitch through size or emotion.

In the current study, we investigate cross-linguistic associations of vocal pitch, including but not limited to the relationship between pitch and politeness. Specifically, we directly compare listeners of Korean, a language where an association between low pitch and politeness has been found (Winter & Grawunder, 2012, though see also Idemaru et al., 2020), and English, a language where an association between high pitch and politeness has been found (Uldall, 1960, 1964; Loveday, 1981; LaPlante & Ambady, 2003). Our study allows us to see whether these results hold in a direct comparison of the two languages, and if they do, whether they reflect across perceptions of first-order attributes of pitch (e.g., physical size, emotion), and/or other higher-order attributes (e.g., seriousness, friendliness).

Our study tests for the effect of pitch using a different paradigm than Winter et al. (2021), who note that “more methodological diversity… [is] needed in order to shed light on the variegated meanings of the pitch [of polite utterances]” (p. 8). Specifically, we use the matched-guise technique (Lambert, Hodgson, Gardner, & Fillenbaum, 1960; van Bezooijen, 1995), in which different versions of the same stimulus are created that differ only in the variable of interest—pitch—and we ask participants to rate the speaker in each stimulus on different attributes. In regular life, a number of acoustic and contextual cues contribute to speaker perception, including to perceptions of speaker politeness (e.g., Nadeu & Prieto, 2011; Brown, Winter, Idemaru, & Grawunder, 2014; Hübscher, Borràs-Comes, & Prieto, 2017), but the matched-guise technique allows us to narrow in on the contribution of pitch alone.

Similarly, while politeness is clearly a complex, culturally- and interactionally-situated phenomenon (Watts, 2003), this design attempts to look at how perceptions of politeness can change when holding the situation constant, and even for relatively contextually impoverished stimuli. In this way, our design also allows politeness to not necessarily be about appropriateness given formality or discernment. In the case of Korean, critically, this allows us to disentangle politeness from register. Register is at least partly obligatory, not necessarily polite, and wrong use of contaymal (the “polite” register) can be perceived as awkward or sarcastic (Hwang, 1990, p. 52; Kim, 2011, p. 195; Brown, 2013). In our study, instead of testing whether someone hears an utterance to have been produced in panmal or contaymal (Brown & Winter, 2014), our study tests whether pitch impacts perceived politeness within panmal, and within contaymal sentences. It is possible that when politeness is defined differently, different patterns of pitch and perceived politeness could emerge (Winter et al., 2021, p.4).

We supplement our result from the matched-guise task with descriptions from participants about what they think “politeness” (“공손함”) means to them. While this sort of direct question is not typical in phonetic studies, given the complexity of politeness as a concept, we find the direct input from our participants to be invaluable in building our interpretation of the results. As a preview of those results, we find that pitch manipulation impacts English and Korean listeners similarly for first-order ratings (e.g., physical size, emotion), but is completely opposite for politeness ratings. In our discussion, we talk about the implications of these findings for work looking at non-arbitrary meaning, especially in cross-cultural contexts.

In a matched-guise speaker perception study in which we manipulated pitch across guises, we found that South Korean listeners heard lower pitched guises as more polite, while U.S. English listeners heard higher-pitched guises as more polite. However, for some other attributes like height, strength, and emotion, listeners in both groups responded similarly to pitch manipulations: Higher pitch led to speakers being perceived as smaller, weaker, and more emotional. In support of the Frequency Code, these results suggest that listeners in both countries have noticed the first-order associations between higher pitch and smaller body size, and also between higher pitch and increased speaker emotion. The cross-linguistic difference, then, appears to exist at a higher indexical order: physical size (and subsequently dominance or submissiveness) and/or emotion (and subsequently restraint or engagement) may play different roles in the two languages when assessing politeness. In this way, our results mirror van Bezooijen (1995), who argued that pitch differences across Japanese and Dutch women do not reflect differences in how lower and higher pitch are understood in terms of size and dominance (i.e., the Frequency Code), but instead reflect differences in the gendered values of these attributes across the two societies.

Participant definitions of politeness give further insight into why the relationship between pitch and politeness may differ in the two populations sampled in the current study. While there was substantial overlap between how South Korean and U.S. listeners conceptualize politeness—both groups’ answers frequently involve respect, manners, and consideration—there are also some key differences. The U.S. listeners frequently mentioned kind in their understanding of politeness, which was rarely mentioned by the South Korean listeners. Conversely, a number of Korean listeners referenced calm, which was arguably never mentioned by the U.S. listeners. This observed difference in conceptions of politeness is not inconsistent with existing, general descriptions of American versus Asian politeness as one of positive politeness versus negative politeness (Brown & Levinson, 1987, pp. 244–249) and also with Ide et al.’s (1992) finding that friendliness appears to be part of the US concept of politeness but is an independent component in Japanese.6 Moreover, the idea of calm matches Hwang’s (1990, p. 52) claim that “‘reservedness’ has traditionally been a typical form of politeness in Korean society.” But most critically for our study, these different emphases in conceptions of politeness appear to impact how higher or lower pitch is evaluated as (im)polite. For Korean listeners, we can posit that lower pitch tends to be heard as more polite due to its association with formality, reservedness, and calmness (Winter et al., 2021). For U.S. English listeners, lower pitch tends to be heard as less polite due to its association with dominance, or possibly because of its association with formality, reservedness, and calmness. One question raised here is how even work that appears to support the Frequency Code (i.e., the English results in this study) may in fact be grounded in different acoustic causes (in this case, pitch and emotion versus pitch and size).

While our results support the idea of the pluripotentiality of vocal pitch (Winter et al., 2021), the current study, along with van Bezooijen (1995), highlights the fact that there can be multiple levels of potential meaning. That is, when framed in terms of orders of indexicality pitch is pluripotential at the first and at the n+ indexical order, and a lack of a relationship at one order (politeness and pitch) does not mean a potential relationship at an earlier order (size and pitch) has not been noticed. This leads us to also argue that cross-linguistic differences in how politeness correlates with vocal pitch become somewhat removed from the evolutionary foundations of the Frequency Code. Locating the relationship between politeness and pitch at a higher order of indexicality that requires a noticing within a specific linguistic community opens up the possibility that not all listeners will notice a relationship between pitch and politeness, and not at all times.

This fact can help explain the variable results within and across studies, as well. Idemaru et al. (2020) also manipulated f0 across guises in Korean, and found weak evidence of an effect in the opposite direction to what we found here (though participants were asked if the speaker was talking to a wi salam or alay salam, not if they sounded polite). In looking at individual participants, they found that the weak effect appeared to be the result of opposing effects at the individual level, with some listeners hearing lower pitched guises as towards wi salam, and others as towards alay salam. In our own data, while we saw that lowering pitch made our speakers sound more polite to Korean listeners overall, the speaker with the lowest mean pitch (KM4) was rated as the least polite speaker, and lowering his pitch actually made him sound even less polite. Moreover, some studies have found that pitch has little or no effect on perceived politeness (Tsurutani & Shi, 2018; Idemaru et al., 2020), and in these cases the potential meanings may be unnoticed or overwhelmed by other, more contextually relevant cues. In other words, just because iconic connections can be made, doesn’t mean they will be, within and across cultures, and within and across individuals and situations.

As a final note, we believe the results of this study also shed light on the distinction between politeness and register (i.e., contaymal vs. panmal) in Korean. Hwang (1990, p. 47) essentially equates the use of an honorific register with deference, claiming that the choice of register is determined largely, “by such power-coded relationships as age disparity and rank in various hierarchical social structures, and by solidarity relationships between the participants.”7 Because registers are marked by morphology, and not phonetics, it is straightforward to judge whether or not an utterance is sufficiently deferential.

Naturally, using an honorific register is a requirement for politeness in a context that requires it. Kim (2011, p. 176) suggested that native Korean folk perceptions of politeness are indeed “intricately associated” with contaymal, and that it is impossible to be polite to a superior without using the correct register. Kim also pointed out, however, that while “an act of showing one’s deference to others is itself a display of politeness, politeness may not necessarily be contingent upon honorifics” (p. 198). In other words, although using a context-appropriate register is a necessary condition for politeness, it may not be sufficient (see examples in Hwang, 1990, p. 48). Thus, although contaymal utterances are considered more polite than panmal utterances, we should not expect all contaymal utterances to be perceived as equally polite, or even necessarily more polite than any and all panmal utterances.

This possibility was demonstrated in the current study in a few ways. It was shown in Section 3.3 that while talkers were indeed rated as more polite when speaking in contaymal (using either supnita or yo) than when speaking in panmal, the size of the difference was quite small (0.49 on a 7-point scale). Moreover, the lowest mean ratings (excluding speaker KM4) given to speakers in the supnita and yo conditions, 4.07 and 3.89, were far lower than the highest mean rating given to a speaker in the panmal condition, 4.85, indicating plenty of overlap in how polite the registers sounded. There is also our basic finding that independent of register, pitch level affected politeness ratings (e.g., lower pitch panmal sentences were rated as more polite than higher pitch panmal sentences), and the fact that in their responses to the open-ended question about what politeness means to them, only four (out of 37) Korean listeners made explicit reference to contaymal or register. Taken together, our results emphasize how Korean conceptualizations of politeness are much richer than register alone.

The present study conceptually replicates previous work showing that lower pitch is heard as more polite in Korean and higher pitch is heard as more polite in English. While this finding goes against some predicted higher order associations of pitch in Ohala’s Frequency Code, we also found that South Korean and US listeners share lower order associations between pitch and size, strength, and emotion. The cross-linguistic differences are therefore the result of differences in how politeness is conceptualized, with metacommentary from participants suggesting this is driven by a greater focus on calmness in Korean politeness, and of kindness in American politeness. Like others, we argue this shows the pluripotential associations pitch can have, but additionally highlight the fact that pluripotentiality operates on multiple levels of indexicality.