Towards a cumulative science of prosody in autism: a cross-linguistic meta-analysis-based investigation of acoustic markers in American and Danish autistic children

Acoustic atypicalities in speech production are widely documented in Autism Spectrum Disorder (ASD) and argued to be both a potential factor in atypical social development and potential markers of clinical features. A recent meta-analysis highlighted shortcomings in the field, in particular small sample sizes and study heterogeneity (Fusaroli, Lambrechts, Bang, Bowler, & Gaigg, 2017). We showcase a cumulative yet self-correcting approach to prosody in ASD to overcome these issues. We analyze a cross-linguistic corpus of multiple speech productions in 77 autistic children and adolescents and 72 TD ones (>1000 recordings in Danish and US English). We replicate findings of a minimal cross-linguistically reliable distinctive acoustic profile for ASD (higher pitch and longer pauses) with moderate effect sizes. We identified novel general reliable differences between the two groups for normalized amplitude quotient, maxima dispersion quotient and creakiness. However, all these relations are small, and there is likely no one general extensive acoustic profile characterizing all autistic individuals. We identified reliable and consistent relations of acoustic features with individual differences (age, gender), and clinical feature: speech rate and ADOS sub-scores (Communication, Social, Stereotyped). Besides cumulatively building our understanding of acoustic atypicalities in ASD, the study concretely shows how to use systematic reviews and meta-analyses to guide follow-up studies, both in their design and their statistical inferences. We indicate future directions: larger and more diverse cross-linguistic datasets, use of previous findings as statistical priors, understanding of covariance between acoustic measures, reliance on machine learning procedures, and open science.

Insights into the Connaught sequence of the Timiskaming varve series from Frederick House Lake, northeastern Ontario

A sub-bottom acoustic profile survey encountered a mass transport deposit (MTD) bed, 5-7 m thick, interbedded within glaciolacustrine deposits of glacial Lake Ojibway at Frederick House Lake, Ontario. Analysis of the thickness patterns of rhythmic couplets in recovered core samples revealed that the Connaught sequence, the youngest of the Timiskaming varve series, immediately under- and overlie the MTD. Comparison to regional published varve series reveals two possible interpretations for the varve numbering. One, varve(v) 2066 to v2115, requires the inference of a 55 varve year (vyr) disconformity just below the Connaught sequence, while alternative numbering, <i>v2011a</i> to <i>v2060a</i> (<i>a</i> – alternative), extends continuously from older varves. Circumstantial evidence supporting the alternative numbering is: i) the uncertainty of applying a common 55 vyr disconformity to three varve series located up to 23 km apart and which otherwise exhibit closely matching thickness plots; ii) the lack of evidence of an erosive unconformity in the sub-bottom acoustic profiles from Frederick House Lake; and iii) the uncertain varve count within a key part of the Matagami series, located abut 300 km away and from which the 55 vyr disconformity is extrapolated. At Frederick House Lake, the alternative numbering indicates that the maximum position of the Cochrane ice advance and the Connaught varves may be, in effect, contemporary in age. More broadly, the alternative numbering indicates that the youngest known varve that formed before the terminal drainage of glacial Lake Ojibway is <i>v2074a</i> rather than v2129 in the original numbering.

Vowel Production in Prelingually Deafened Mandarin-Speaking Children With Cochlear Implants

Purpose The purpose of this study was to characterize the acoustic profile and to evaluate the intelligibility of vowel productions in prelingually deafened, Mandarin-speaking children with cochlear implants (CIs). Method Twenty-five children with CIs and 20 age-matched children with normal hearing (NH) were recorded producing a list of Mandarin disyllabic and trisyllabic words containing 20 Mandarin vowels [a, i, u, y, ɤ, ɿ, ʅ, ai, ei, ia, ie, ye, ua, uo, au, ou, iau, iou, uai, uei] located in the first consonant–vowel syllable. The children with CIs were all prelingually deafened and received unilateral implantation before 7 years of age with an average length of CI use of 4.54 years. In the acoustic analysis, the first two formants (F1 and F2) were extracted at seven equidistant time locations for the tested vowels. The durational and spectral features were compared between the CI and NH groups. In the vowel intelligibility task, the extracted vowel portions in both NH and CI children were presented to six Mandarin-speaking, NH adult listeners for identification. Results The acoustic analysis revealed that the children with CIs deviated from the NH controls in the acoustic features for both single vowels and compound vowels. The acoustic deviations were reflected in longer duration, more scattered vowel categories, smaller vowel space area, and distinct formant trajectories in the children with CIs in comparison to NH controls. The vowel intelligibility results showed that the recognition accuracy of the vowels produced by the children with CIs was significantly lower than that of the NH children. The confusion pattern of vowel recognition in the children with CIs generally followed that in the NH children. Conclusion Our data suggested that the prelingually deafened children with CIs, with a relatively long duration of CI experience, still showed measurable acoustic deviations and lower intelligibility in vowel productions in comparison to the NH children.

The Weakest Point Evaluation Method for the Control Range of the Sound Velocity Profile Station

Sound velocity measurement is an important part of multi-beam sounding, and its accuracy directly affects the coordinate reduction of sounding points. Because of the variability of seawater sound velocity in time and space, the layout density of acoustic section stations directly affects the accuracy of multi-beam sounding. Over-dense layout wastes resources and causes inefficiency; over-sparse layout is not accurate enough to control the entire survey area. Based on the constant gradient acoustic ray tracing algorithm, this paper constructs the accuracy evaluation model of the weakest water depth point of acoustic profile station control, and analyses whether the existing multi-beam acoustic profile station layout scheme can satisfy the accuracy requirements of multi-beam sounding through an example calculation, which provides a theoretical basis for adjusting the layout scheme of acoustic profile station for field surveyors.

Polyadic Cantor Fractal Ultrasonic Lenses: Design and Characterization

Traditional acoustic lenses modulate the ultrasonic beam due to their curved surfaces and the refractive material of which they are made. In this work, a different type of acoustic lens, based on Polyadic Cantor Fractals (PCF), is presented and thoroughly analyzed. These new Polyadic Cantor Fractal Lenses (PCFLs) are completely flat and easy to build, and they present interesting modulation capabilities over the acoustic profile. The dependence of the focusing profile on the PCFL design parameters is fully characterized, and it is shown that certain design parameters provide a dynamic control, which is critical in many medical applications such as thermal ablation of tumors.

Overlap among back vowels before /l/ in Kansas City

This research examines pre-/l/ allophones of vowels in five lexical sets—GOOSE, FOOT, GOAT, STRUT, and THOUGHT—in Kansas City. It builds an acoustic profile from 5507 tokens drawn from interviews with 67 Kansas Citians born between 1955 and 1999. Results reveal a variety of overlap patterns among all five vowels, with the most widespread being overlap between the pre-/l/ allophones of FOOT, STRUT, and GOAT. Acoustically, overlap patterns generally do not show a trend of change in apparent time. However, responses to minimal pairs reveal substantial apparent-time increases in judgments of “close” or “same.” Speakers appear to adjust their productions of vowels to match their minimal pair judgments. The interaction of these productions and judgments indicates a different profile for these five vowels than has been observed in other communities and suggests that some of these vowels have become phonemically ambiguous in Kansas City.

The use of discourse markers in L2 Italian

This exploratory study intends to investigate the use of discourse markers (DM) in Italian L2 by learners with different L1s and different levels of competence (three at A2/B1 level and two at B2/C1 level). The analysis aims to describe the functions, the distribution, and some acoustic features of three DMs (però ‘but’, allora ‘then’, quindi ‘therefore’) in semi-spontaneous conversations between the learners and two native speakers. The purpose is to determine the possible uses and the relationship between the forms and functions of the DMs in native and non-native speakers distinguishing three main macro-functions (interactional, cognitive and metadiscursive) activated by speakers on the basis of the characteristics of the cotext (acoustic profiles), the context and the communicative situation. Such an analysis suggests a possible sequence in the emergence of DMs in the speech of L2 learners with different levels of competence in the target language. This exploratory study adopts a functional approach (Bazzanella 1995a, b; 2006; Fisher 2006). The outcomes of the analysis show that learners use a variety of DM forms and functions, and that some functions only emerge in more proficient speakers. The structural context and, to a lesser degree, the acoustic profile prove to be reliable indicators of the spectrum of functions performed by DMs in verbal interaction.