The bouba/kiki effect—the association of the nonce word bouba with a round shape and kiki with a spiky shape—is a type of correspondence between speech sounds and visual properties with potentially deep implications for the evolution of spoken language. However, there is debate over the robustness of the effect across cultures and the influence of orthography. We report an online experiment that tested the bouba/kiki effect across speakers of 25 languages representing nine language families and 10 writing systems. Overall, we found strong evidence for the effect across languages, with bouba eliciting more congruent responses than kiki . Participants who spoke languages with Roman scripts were only marginally more likely to show the effect, and analysis of the orthographic shape of the words in different scripts showed that the effect was no stronger for scripts that use rounder forms for bouba and spikier forms for kiki . These results confirm that the bouba/kiki phenomenon is rooted in crossmodal correspondence between aspects of the voice and visual shape, largely independent of orthography. They provide the strongest demonstration to date that the bouba/kiki effect is robust across cultures and writing systems. This article is part of the theme issue ‘Voice modulation: from origin and mechanism to social impact (Part II)’.

Linguistic communication requires speakers to mutually agree on the meanings of words, but how does such a system first get off the ground? One solution is to rely on iconic gestures: visual signs whose form directly resembles or otherwise cues their meaning without any previously established correspondence. However, it is debated whether vocalizations could have played a similar role. We report the first extensive cross-cultural study investigating whether people from diverse linguistic backgrounds can understand novel vocalizations for a range of meanings. In two comprehension experiments, we tested whether vocalizations produced by English speakers could be understood by listeners from 28 languages from 12 language families. Listeners from each language were more accurate than chance at guessing the intended referent of the vocalizations for each of the meanings tested. Our findings challenge the often-cited idea that vocalizations have limited potential for iconic representation, demonstrating that in the absence of words people can use vocalizations to communicate a variety of meanings.

Language disorders cover a wide range of conditions with heterologous and overlapping phenotypes and complex etiologies harboring both genetic and environmental influences. Genetic approaches including the identification of genes linked to speech and language phenotypes and the characterization of normal and aberrant functions of these genes have, in recent years, unraveled complex details of molecular and cognitive mechanisms and provided valuable insight into the biological foundations of language. Consistent with this approach, we have reviewed the functional aspects of allelic variants of genes which are currently known to be either causally associated with disorders of speech and language or impact upon the spectrum of normal language ability. We have also reviewed candidate genes associated with heritable speech and language disorders. In addition, we have evaluated language phenotypes and associated genetic components in developmental syndromes that, together with a spectrum of altered language abilities, manifest various phenotypes and offer details of multifactorial determinants of language function. Data from this review have revealed a predominance of regulatory networks involved in the control of differentiation and functioning of neurons, neuronal tracks and connections among brain structures associated with both cognitive and language faculties. Our findings, furthermore, have highlighted several multifactorial determinants in overlapping speech and language phenotypes. Collectively this analysis has revealed an interconnected developmental network and a close association of the language faculty with cognitive functions, a finding that has the potential to provide insight into linguistic hypotheses defining in particular, the contribution of genetic elements to and the modular nature of the language faculty.

Hungarian prosody is left-headed, as suggested by the placement of the accent on the initial syllable on the level of prosodic words and the placement of the strongest pitch accent on the first accented word of the prosodic phrase. Earlier studies have pointed out that the left edge of the intonational phrase can bear a phrase-initial boundary tone that distinguishes between stringidentical wh-interrogatives and wh-exclamatives. In this paper, two other string-identical sentence types, polar questions and declaratives, are investigated with respect to their prosodic features. Polar questions were characterised by a higher f0 maximum and a lower sentence-initial f0 than declaratives. The only pitch accent within the sentence was low, whereas declaratives had falling pitch accents. Sentence-final f0 and the pitch level of the accented syllable did not show a consistent pattern across speakers. It is concluded that low sentence-initial f0 together with the high t! one on the penultimate syllable is a relevant marker of polar questions in Hungarian.

Infant-directed speech (IDS) has been found to be characterised by higher fundamental frequency, wider pitch range, higher energy, lower speech rate and various other factors. These tendencies occur in most languages, although with some interlanguage variation. This study tries to establish these measures for the speech of Hungarian mothers of newborn babies who differ in terms of their maternal parity. Both mothers who gave birth for the first time (primipara, PP) and mothers with multiple pregnancies (multipara, MP) use higher pitch when talking to their babies as opposed to an adult. An overall increase of f0 in both speaking styles was observed for multipara mothers, although statistically not significant. IDS of this group was also characterised by higher energy and more prominent pitch accents, while these effects were missing from the IDS of primipara mothers. Directedness or parity had no effect on syllable rate.