Glyph guessing for 'oo' and 'ee': spatial frequency information in sound symbolic matching for ancient and unfamiliar scripts

The Bouba-Kiki effect is predicted by sound properties but not speech properties

Humans robustly associate spiky shapes to words like "Kiki" and round shapes to words like "Bouba." According to a popular explanation, this is because the mouth assumes an angular shape while speaking "Kiki" and a rounded shape for "Bouba." Alternatively, this effect could reflect more general associations between shape and sound that are not specific to mouth shape or articulatory properties of speech. These possibilities can be distinguished using unpronounceable sounds: The mouth-shape hypothesis predicts no Bouba-Kiki effect for these sounds, whereas the generic shape-sound hypothesis predicts a systematic effect. Here, we show that the Bouba-Kiki effect is present for a variety of unpronounceable sounds ranging from reversed words and real object sounds (n = 45 participants) and even pure tones (n = 28). The effect was strongly correlated with the mean frequency of a sound across both spoken and reversed words. The effect was not systematically predicted by subjective ratings of pronounceability or with mouth aspect ratios measured from video. Thus, the Bouba-Kiki effect is explained using simple shape-sound associations rather than using speech properties.

The AI trilemma: Saving the planet without ruining our jobs

Digitalization and artificial intelligence increasingly affect the world of work. Rising risk of massive job losses have sparked technological fears. Limited income and productivity gains concentrated among a few tech companies are fueling inequalities. In addition, the increasing ecological footprint of digital technologies has become the focus of much discussion. This creates a trilemma of rising inequality, low productivity growth and high ecological costs brought by technological progress. How can this trilemma be resolved? Which digital applications should be promoted specifically? And what should policymakers do to address this trilemma? This contribution shows that policymakers should create suitable conditions to fully exploit the potential in the area of network applications (transport, information exchange, supply, provisioning) in order to reap maximum societal benefits that can be widely shared. This requires shifting incentives away from current uses toward those that can, at least partially, address the trilemma. The contribution analyses the scope and limits of current policy instruments in this regard and discusses alternative approaches that are more aligned with the properties of the emerging technological paradigm underlying the digital economy. In particular, it discusses the possibility of institutional innovations required to address the socio-economic challenges resulting from the technological innovations brought about by artificial intelligence.

The puzzle of ideography

An ideography is a general-purpose code made of pictures that do not encode language, which can be used autonomously - not just as a mnemonic prop - to encode information on a broad range of topics. Why are viable ideographies so hard to find? I contend that self-sufficient graphic codes need to be narrowly specialized. Writing systems are only an apparent exception: At their core, they are notations of a spoken language. Even if they also encode nonlinguistic information, they are useless to someone who lacks linguistic competence in the encoded language or a related one. The versatility of writing is thus vicarious: Writing borrows it from spoken language. Why is it so difficult to build a fully generalist graphic code? The most widespread answer points to a learnability problem. We possess specialized cognitive resources for learning spoken language, but lack them for graphic codes. I argue in favor of a different account: What is difficult about graphic codes is not so much learning or teaching them as getting every user to learn and teach the same code. This standardization problem does not affect spoken or signed languages as much. Those are based on cheap and transient signals, allowing for easy online repairing of miscommunication, and require face-to-face interactions where the advantages of common ground are maximized. Graphic codes lack these advantages, which makes them smaller in size and more specialized.

Japanese Sound-Symbolic Words for Representing the Hardness of an Object Are Judged Similarly by Japanese and English Speakers

Contrary to the assumption of arbitrariness in modern linguistics, sound symbolism, which is the non-arbitrary relationship between sounds and meanings, exists. Sound symbolism, including the “Bouba–Kiki” effect, implies the universality of such relationships; individuals from different cultural and linguistic backgrounds can similarly relate sound-symbolic words to referents, although the extent of these similarities remains to be fully understood. Here, we examined if subjects from different countries could similarly infer the surface texture properties from words that sound-symbolically represent hardness in Japanese. We prepared Japanese sound-symbolic words of which novelty was manipulated by a genetic algorithm (GA). Japanese speakers in Japan and English speakers in both Singapore and the United States rated these words based on surface texture properties (hardness, warmness, and roughness), as well as familiarity. The results show that hardness-related words were rated as harder and rougher than softness-related words, regardless of novelty and countries. Multivariate analyses of the ratings classified the hardness-related words along the hardness-softness dimension at over 80% accuracy, regardless of country. Multiple regression analyses revealed that the number of speech sounds /g/ and /k/ predicted the ratings of the surface texture properties in non-Japanese countries, suggesting a systematic relationship between phonetic features of a word and perceptual quality represented by the word across culturally and linguistically diverse samples.

The bouba/kiki effect is robust across cultures and writing systems

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)'.

A thirteenth-century theory of speech

This historical paper examines a pioneering theory of speech production and perception from the thirteenth century. Robert Grosseteste (c.1175—1253) was a celebrated medieval thinker, who developed an impressive corpus of treatises on the natural world. This paper looks at his treatise on sound and phonetics, De generatione sonorum [On the Generation of Sounds]. Through interdisciplinary analysis of the text, this paper finds a theory of vowel production and perception that is notably mathematical, with a formulation of vowel space rooted in combinatorics. Specifically, Grosseteste constructs a categorical space comprising three fundamental types of movements pertaining to the vocal apparatus: linear, circular, and dilational-constrictional; these correspond to similarity transformations of translation, rotation, and uniform scaling, respectively. That Grosseteste's space is categorical, and low-dimensional, is remarkable vis-a-vis current theories of phoneme perception. As well as his description of vowel space, Grosseteste also sets out a hypothetical framework of multisensory integration, uniting the production, perception, and representation in writing of vowels with a set of geometric figures associated with “mental images.” This has clear resonances with contemporary studies of motor facilitation during speech perception and audiovisual speech. This paper additionally provides an experimental foray, illustrating the coherence of mathematical and scientific thinking underpinning this early theory.

Sound symbolism in sighted and blind. The role of vision and orthography in sound-shape correspondences

Non-arbitrary sound-shape correspondences (SSC), such as the "bouba-kiki" effect, have been consistently observed across languages and together with other sound-symbolic phenomena challenge the classic linguistic dictum of the arbitrariness of the sign. Yet, it is unclear what makes a sound "round" or "spiky" to the human mind. Here we tested the hypothesis that visual experience is necessary for the emergence of SSC, supported by empirical evidence showing reduced SSC in visually impaired people. Results of two experiments comparing early blind and sighted individuals showed that SSC emerged strongly in both groups. Experiment 2, however, showed a partially different pattern of SSC in sighted and blind, that was mostly explained by a different effect of orthographic letter shape: The shape of written letters (spontaneously activated by spoken words) influenced SSC in the sighted, but not in the blind, who are exposed to an orthography (Braille) in which letters do not have spiky or round outlines. In sum, early blindness does not prevent the emergence of SSC, and differences between sighted and visually impaired people may be due the indirect influence (or lack thereof) of orthographic letter shape.

Assessing sound symbolism: Investigating phonetic forms, visual shapes and letter fonts in an implicit bouba-kiki experimental paradigm

Classically, in the bouba-kiki association task, a subject is asked to find the best association between one of two shapes–a round one and a spiky one–and one of two pseudowords–bouba and kiki. Numerous studies report that spiky shapes are associated with kiki, and round shapes with bouba. This task is likely the most prevalent in the study of non-conventional relationships between linguistic forms and meanings, also known as sound symbolism. However, associative tasks are explicit in the sense that they highlight phonetic and visual contrasts and require subjects to establish a crossmodal link between stimuli of different natures. Additionally, recent studies have raised the question whether visual resemblances between the target shapes and the letters explain the pattern of association, at least in literate subjects. In this paper, we report a more implicit testing paradigm of the bouba-kiki effect with the use of a lexical decision task with character strings presented in round or spiky frames. Pseudowords and words are, furthermore, displayed with either an angular or a curvy font to investigate possible graphemic bias. Innovative analyses of response times are performed with GAMLSS models, which offer a large range of possible distributions of error terms, and a generalized Gama distribution is found to be the most appropriate. No sound symbolic effect appears to be significant, but an interaction effect is in particular observed between spiky shapes and angular letters leading to faster response times. We discuss these results with respect to the visual saliency of angular shapes, priming, brain activation, synaesthesia and ideasthesia.