Vocal-Tract Resonances as Indexical Cues in Rhesus Monkeys

By Asif A. Ghazanfar, Hjalmar K. Turesson, Joost X. Maier, R. van Dinther, Roy D. Patterson, Nikos K. Logothetis. 2007

173 citations recorded by the source corpus.

Summary Vocal-tract resonances (or formants) are acoustic signatures in the voice and are related to the shape and length of the vocal tract. Formants play an important role in human communication, helping us not only to distinguish several different speech sounds [1], but also to extract important information related to the physical characteristics of the speaker, so-called indexical cues. How did formants come to play such an important role in human vocal communication? One hypothesis suggests that the ancestral role of formant perception—a role that might be present in extant nonhuman primates—was to provide indexical cues [2-5]. Although formants are present in the acoustic structure of vowel-like calls of monkeys [3-8] and implicated in the discrimination of call types [8-10], it is not known whether they use this feature to extract indexical cues. Here, we investigate whether rhesus monkeys can use the formant structure in their “coo” calls to assess the age-related body size of conspecifics. Using a preferential-looking paradigm [11, 12] and synthetic coo calls in which formant structure simulated an adult/large- or juvenile/small-sounding individual, we demonstrate that untrained monkeys attend to formant cues and link large-sounding coos to large faces and small-sounding coos to small faces—in essence, they can, like humans [13], use formants as indicators of age-related body size.

Subfields: Developmental Biology, Signal Processing

How researchers see this paper

The researchers whose trusted networks rank it highest, strongest advocate first. Every researcher gets a different order.

In Developmental Biology

In Signal Processing

Citations in the corpus

Early Experience & Multisensory Perceptual Narrowing (2014, background): “…all can perceive the correspondence of facial and vocal expressions during communicative encounters (Adachi, Kuwahata, Fujita, Tomonaga, & Matsuzawa, 2006; Ghazanfar & Logothetis, 2003; Ghazanfar et al., 2007; Izumi & Kojima, 2004; Jordan, Brannon, Logothetis, & Ghazanfar, 2005; Parr, 2004).”
Facilitation of multisensory integration by the "unity effect" reveals that speech is special. (2008, background): “It is, however, important to note that speech represents a very familiar stimulus to humans.”
The contribution of source–filter theory to mammal vocal communication research (2010, background): “Moreover, rhesus monkeys are able to associate smaller formant dispersions with pictures of larger (mature) conspecifics and wider formant dispersions with pictures of smaller (immature) individuals (Ghazanfar et al., 2007), demonstrating an intermodal (auditory to visual) understanding of size.”
Taller men are less sensitive to cues of dominance in other men (2010, background): “2010) and in studies of voice quality and dominance in other mammalian species (Reby et al. 2005; Ghazanfar et al. 2007).”
Heterochrony and Cross-Species Intersensory Matching by Infant Vervet Monkeys (2009, background): “infant Old World monkeys [6,7,8,9] and humans [10,11,12].”
A domain-specific opposite-sex bias in human preferences for manipulated voice pitch. (2010, background): “2008) and in studies of voice quality, dominance and mate preferences among other mammalian species (Reby et al. 2005; Ghazanfar et al. 2007).”
Size Communication in domestic dog (Canis familiaris) growls. (2010, unknown): “…captive rhesus macaques have demonstrated in an operant learning task that they are able to associate calls with a small formant dispersion with pictures of large (mature) conspecifics and calls with a large formant dispersion with pictures of small (immature) conspecifics (Ghazanfar et al. 2007).”
Correlated preferences for men's facial and vocal masculinity (2008, background): “, 2005) and rhesus macaques (Fitch & Fritz, 2006; Ghazanfar et al., 2007).”
Vertebrate Sound Production and Acoustic Communication (2016, background): “…al. 1998 ; Rendall 2003 ) has sparked a renewed interest in the role of formants in primate vocal production (Riede et al. 2005 ; Ey et al. 2007 ; Ghazanfar et al. 2007 ), including both heliox experiments (Koda et al. 2012 ) and playback experiments in which formant frequencies are…”