Postural adaptation to microgravity underlies fine motor impairment in astronauts' speech

Understanding the role of anti-gravity behaviour in fine motor control is crucial to achieving a unified theory of motor control. We compare speech from astronauts before and immediately after microgravity exposure to evaluate the role of anti-gravity posture during fine motor skills. Here we show a generalized lowering of vowel space after space travel, which suggests a generalized postural shift of the articulators. Biomechanical modelling of gravitational effects on the vocal tract supports this analysis-the jaw and tongue are pulled down in 1g, but movement trajectories of the tongue are otherwise unaffected. These results demonstrate the role of anti-gravity posture in fine motor behaviour and provide a basis for the unification of motor control models across domains.

Trilled /r/ is associated with roughness, linking sound and touch across spoken languages

Cross-modal integration between sound and texture is important to perception and action. Here we show this has repercussions for the structure of spoken languages. We present a new statistical universal linking speech with the evolutionarily ancient sense of touch. Words that express roughness—the primary perceptual dimension of texture—are highly likely to feature a trilled /r/, the most commonly occurring rhotic consonant. In four studies, we show the pattern to be extremely robust, being the first widespread pattern of iconicity documented not just across a large, diverse sample of the world’s spoken languages, but also across numerous sensory words within languages. Our deep analysis of Indo-European languages and Proto-Indo-European roots indicates remarkable historical stability of the pattern, which appears to date back at least 6000 years.

Beyond Plain and Extra-Grammatical Morphology: Echo-Pairs in Hungarian

This paper presents an investigation of echo-pairs in Hungarian. Echo-pairs are formed by duplicating a base with an altered initial consonant and have diminutive, playful, or intimate connotations (e.g., cica [t͡sit͡sɒ] "cat" → cica-mica [t͡sit͡sɒ-mit͡sɒ] "cat.dim"). Echo-pairs are commonly seen as an example of extra-grammatical morphology in the literature. Our goal in looking at this phenomenon is to gain a better understanding of the morphological mechanisms underlying extra-grammatical phenomena and shed new light on the distinction between plain and extra-grammatical morphology. We analyze data from (a) a collection of echo-pairs extracted from a large corpus of online texts and (b) a large-scale online nonce-word experiment with close to 1,500 participants. Our results reveal two key phonological patterns in the data and some additional systematic variation across words and experimental stimuli. We compare two different models of morphology, the Minimal Generalization Learner and the Generalized Context Model, in terms of their ability to capture this variation. We find that echo-pair formation is best captured by lexicon-oriented models such as the Generalized Context Model, but only when they rely on a structured similarity metric that encodes broader generalizations about the data. Our results do not support a clear-cut distinction between extra-grammatical and plain morphological processes, and we suggest that some of the peculiar characteristics of extra-grammatical phenomena such as echo-pair formation may simply follow from their special function and the limited set of contexts in which they appear.