A perspective review on the role of engine sound in speed perception and control: state of the art and methodological suggestions.

In this review we focus on the role of in-car sound, specifically the artificial engine sounds, on drivers' speed perception and control, a topic that has received little attention so far. Previous studies indicate that removing or reducing engine sound leads drivers to underestimate speed and, consequently, to drive faster. Furthermore, evidence suggests that specific sound frequencies could play a role in this process, highlighting the importance of in-car sound features. First, we show that the amount of research in the field is scarce and rather outdated, and that this is largely due to the fact that industrial research is subject to very few publications. Then, we examine benefits and limitations of different research paradigms used and we propose a protocol to investigate systematically the phenomenon. In particular, we argue for the benefits of a wider use of psychophysical methods in speed perception, a field that has been typically explored by means of driving simulation. Finally, we highlight some methodological and statistical limitations that might impact the interpretation of the evidence considered. Our methodological considerations could be particularly useful for researchers aiming to investigate the impact of sound on speed perception and control, as well as for those involved in the design of in-car sounds. These are particularly relevant for the design of electric vehicles, which represent a challenge but also the ideal testing ground to advance the knowledge in the field.

A new test for evaluation of marginal cognitive function deficits in idiopathic normal pressure hydrocephalus through expressing texture recognition by sound symbolic words.

Introduction: The number of dementia patients is increasing with population aging. Preclinical detection of dementia in patients is essential for access to adequate treatment. In previous studies, dementia patients showed texture recognition difficulties. Onomatopoeia or sound symbolic words (SSW) are intuitively associated with texture impressions and are less likely to be affected by aphasia and description of material perception can be easily obtained. In this study, we aimed to create a test of texture recognition ability expressed by SSW to detect the presence of mild cognitive disorders. Methods: The sound symbolic words texture recognition test (SSWTRT) is constructed from 12 close-up photos of various materials and participants were to choose the best SSW out of 8 choices to describe surface texture in the images in Japanese. All 102 participants seen in Juntendo University Hospital from January to August 2023 had a diagnosis of possible iNPH (age mean 77.9, SD 6.7). The answers were scored on a comprehensive scale of 0 to 1. Neuropsychological assessments included MMSE, FAB, and the Rey Auditory Verbal Learning Test (RAVLT), Pegboard Test, and Stroop Test from the EU-iNPH Grading Scale (GS). In study 1 the correlation between SSWTRT and the neuropsychological tests were analyzed. In study 2, participants were divided into two groups: the Normal Cognition group (Group A, n = 37) with MMSE scores of 28 points or above, and the Mild Cognitive Impairment group (Group B, n = 50) with scores ranging from 22 to 27 points, and its predictability were analyzed. Results: In study 1, the total SSWTRT score had a moderate correlation with the neuropsychological test results. In study 2, there were significant differences in the SSWTRT scores between groups A and B. ROC analysis results showed that the SSWTR test was able to predict the difference between the normal and mildly impaired cognition groups. Conclusion: The developed SSWTRT reflects the assessment results of neuropsychological tests in cognitive deterioration and was able to detect early cognitive deficits. This test not only relates to visual perception but is likely to have an association with verbal fluency and memory ability, which are frontal lobe functions.

Gender and age biases in the assessment of speech accuracy: A study of speech-language clinicians' ratings of /s/ accuracy.

PURPOSE: Typically developing children assigned male at birth (AMAB) and children assigned female at birth (AFAB) produce the fricative /s/ differently: AFAB children produce /s/ with a higher spectral peak frequency. This study examined whether implicit knowledge of these differences affects speech-language pathologists'/speech and language therapists' (SLPs'/SLTs') ratings of /s/ accuracy, by comparing ratings made in conditions where SLPs/SLTs were blind to children's sex assigned at birth (SAB) to conditions in which they were told this information. METHODS: SLPs (n = 95) varying in clinical experience rated the accuracy of word-initial /s/ productions (n = 87) of eight children with speech sound disorder in one of four conditions: one in which no information about the children was revealed, one in which children's SAB was revealed, one in which children's age was revealed, and one in which both were revealed. RESULTS: Despite there being no statistically significant differences between AFAB and AMAB children's /s/ production in researcher-determined accuracy or in one acoustic characteristic, spectral centroid, SLPs in all four conditions judged the /s/ productions of AFAB children as more accurate than AMAB children. Listeners were significantly less likely to judge the productions of AMAB children to be inaccurate in the conditions in which age or age and SAB were revealed. These effects were consistent across SLPs with greatly varying levels of clinical experience. CONCLUSION: Knowing or imputing children's age and SAB can affect ratings of /s/ accuracy. Clinicians should be mindful of these potential effects. Future research should understand how expectations about sociolinguistic variation in speech affect appraisals of their speech and language. WHAT THIS PAPER ADDS: What is already known on the subject Adult men and women produce /s/ differently. A consensus is that these differences reflect sociolinguistic gender marking, rather than being the passive consequence of vocal-tract differences. Recent studies have shown that children assigned female at birth (AFAB) and those assigned male at birth (AMAB) produce /s/ differently in ways that mirror the differences between adult men and women, and which presumably reflect gender marking. What this paper adds to existing knowledge We asked whether US-based speech-language pathologists' (SLPs) ratings of the accuracy of /s/ differ depending on whether they are rating an AFAB or an AMAB child, and whether these differences are greater in conditions in which people are told the sex assigned at birth of the child being rated. We found that SLPs were more likely to judge AFAB children's /s/ productions to be more accurate than AMAB children's, even though the productions from the AMAB and AFAB children that were used as stimuli were matched for accuracy as determined by trained researchers. What are the clinical implications of this work? SLPs/speech-language therapists should be sensitive to the influence of social variables when assessing /s/. SLPs/speech-language therapists might rate children's productions differently depending on whether they believe they are rating an AFAB or an AMAB child.

Quieting the neonatal intensive care unit: A quality improvement initiative.

BACKGROUND: The neonatal intensive care unit (NICU) is vital for preterm infants but is often plagued by harmful noise levels. Excessive noise, ranging from medical equipment to conversations, poses significant health risks, including hearing impairment and neurodevelopmental issues. The American Academy of Pediatrics recommends strict sound limits to safeguard neonatal well-being. Strategies such as education, environmental modifications, and quiet hours have shown to reduce noise levels. However, up to 60% of the noises remain avoidable. High noise exposure exacerbates physiological disturbances, impacting vital functions and long-term neurological outcomes. Effective noise reduction in the NICU is crucial for promoting optimal neonatal development. AIM: To measure the sound levels in a NICU and reduce ambient sound levels by at least 10% from baseline. METHODS: A quasi-experimental quality improvement project was conducted over 4 mo in a 20-bed level 3 NICU in a tertiary care medical college. Baseline noise levels were recorded continuously using a sound level meter. The interventions included targeted education, environmental modifications, and organizational changes, and were implemented through three rapid Plan-Do-Study-Act (PDSA) cycles. Weekly feedback and monitoring were conducted, and statistical process control charts were used for analysis. The mean noise values were compared using the paired t-test. RESULTS: The baseline mean ambient noise level in the NICU was 67.8 dB, which decreased to 50.5 dB after the first cycle, and further decreased to 47.4 dB and 51.2 dB after subsequent cycles. The reduction in noise levels was 21% during the day and 28% at night, with an overall decrease of 25% from baseline. The most significant reduction occurred after the first PDSA cycle (mean difference of -17.3 dB, P < 0.01). Peak noise levels decreased from 110 dB to 88.24 dB after the intervention. CONCLUSION: A multifaceted intervention strategy reduced noise in the NICU by 25% over 4 months. The success of this initiative emphasizes the significance of comprehensive interventions for noise reduction.

Effect of Soundscape Augmentation on Behavioral Symptoms in People With Dementia: A Pilot Randomized Controlled Trial.

Background and Objectives: Sound is an important environmental factor that influences the expression of behavioral and psychological symptoms of dementia. Recent research on the effect of soundscape has shown promising results in improving environmental impact on people with dementia. However, no controlled studies have aimed to quantify the effects of soundscape intervention on resident outcomes. The aim of this study was to assess the feasibility and impact of a soundscape intervention on people with dementia and behavioral symptoms. Research Design and Methods: Pilot single-blind repeated-measures randomized controlled trial of an augmented soundscape intervention. Participants were people with dementia in a hospital-based specialized dementia unit. Participants were randomized to an augmented soundscape intervention delivered in their room in the morning and evening or treatment as usual, with 2 baseline weeks and 4 weekly post-randomization assessments of the primary and secondary behavioral outcomes. Results: The soundscape intervention was feasible in terms of recruitment, retention, and delivery of the intervention. There were improvements in the neuropsychiatric inventory total scores over time in both groups (-5.89, 95%CI -8.45 to -3.28, p < .001), but no differences between groups. There were no significant group, time, or group × time differences for the Pittsburgh Agitation Scale (PAS) total score. For the PAS-resisting care subscale, there was a significant group × time difference, with a greater reduction in the soundscape group over the study period (-0.81, 95% CI -1.59 to -0.03, p = .042). Discussion and Implications: In this pilot study, soundscape augmentation was a feasible and effective nonpharmacological approach to reducing resistance to care in people with dementia, although it did not improve neuropsychiatric symptoms more globally. Further studies with larger samples and of longer duration are needed to investigate the long-term effects of augmented sonic environments on people with dementia. Clinical Trials Registration Number: NCT04809545.

Correlation between BMI, amount of aspirated fat and post-operative complications in VASER liposuction: A single centre experience.

Background: Vibration amplification of sound energy at resonance (VASER) liposuction is an innovative technique that allows surgeons to selectively remove fat and shape desired areas of the body, resulting in more precise and controlled outcomes compared to traditional liposuction techniques. VASER liposuction offers several advantages, including targeted action that reduces trauma to the surrounding tissues, limiting pain, swelling and recovery time. Purpose: This study compared the complication rates among patients who underwent VASER liposuction in relation to their body mass index (BMI) and the amount of fat aspirated. Methods: The authors reviewed the medical records of all patients who underwent VASER liposuction at Scalera Clinic in Naples, dividing them into two groups: the first with BMI < 24.9 kg/m2 and second with BMI >25.0 kg/m2. Results: The authors examined 117 patients who were operated on within a year (2022/2023), with 48 of them having BMIs < 24.9 kg/m2 and 69 showing BMIs >25.0 kg/m2. In patients with a BMI >25 kg/m2, the most common complications were contusion, hematomas and abnormal skin retraction, whereas no complications were observed in the patients with normal-weight. Conclusions: To minimise post-operative complications and maximise results, it is advisable to select patients based on their BMI assessment, the anatomy of the treated body area and the volume of fat to be removed. This approach aims to ensure that the patients are suitable for the procedure and the achieved results align with their aesthetic expectations.

The relationship of speech perception and speech production: It's complicated.

A widely held belief is that speech perception and speech production are tightly linked, with each modality available to help with learning in the other modality. This positive relationship is often summarized as perception and production being "two sides of the same coin." There are, indeed, many situations that have shown this mutually supportive relationship. However, there is a growing body of research showing very different results, with the modalities operating independently, or even in opposition to each other. We review the now-sizeable literature demonstrating the negative effect that speech production can have on perceptual learning of speech, at multiple levels (particularly at the lexical and sublexical levels). By comparing the situations that show this pattern with ones in which more positive interactions occur, we provide an initial account of why the different outcomes are found, identifying factors that lead to either positive or negative effects of production on perception. The review clarifies the complex relationship that exists between the two modalities: They are indeed linked, but their relationship is more complicated than is suggested by the notion that they are two sides of the same coin.

Considerations for identifying subtypes of speech sound disorder.

BACKGROUND: Speech sound disorders (SSDs) in children are heterogeneous. Differentiating children with SSDs into distinct subtypes is important so that each child receives a treatment approach well suited to the particular difficulties they are experiencing. AIMS: To study the distinct underlying processes that differentiate phonological processing, phonological planning or motor planning deficits. METHOD: The literature on the nature of SSDs is reviewed to reveal diagnostic signs at the level of distal causes, proximal factors and surface characteristics. MAIN CONTRIBUTION: Subtypes of SSDs may be identified by linking the surface characteristics of the children's speech to underlying explanatory proximal factors. The proximal factors may be revealed by measures of speech perception skills, phonological memory and speech-motor control. The evidence suggests that consistent phonological disorder (CPD) can be identified by predictable patterns of speech error associated with speech perception errors. Inconsistent phonological disorder (IPD) is associated with a deficit in the selection and sequencing of phonemes, that is, revealed as within-word inconsistency and poor phonological memory. The motor planning deficit that is specific to childhood apraxia of speech (CAS) is revealed by transcoding errors on the syllable repetition task and an inability to produce [pətəkə] accurately and rapidly. CONCLUSIONS & IMPLICATIONS: Children with SSDs form a heterogeneous population. Surface characteristics overlap considerably among those with severe disorders, but certain signs are unique to particular subtypes. Careful attention to underlying causal factors will support the accurate diagnosis and selection of personalized treatment options. WHAT THIS PAPER ADDS: What is already known on the subject SSD in children are heterogenous, with numerous subtypes of primary SSD proposed. Diagnosing the specific subtype of SSD is important in order to assign the most efficacious treatment approach for each child. Identifying the distinct subtype for each child is difficult because the surface characteristics of certain subtypes overlap among categories (e.g., CPD or IPD; CAS). What this paper adds to the existing knowledge The diagnostic challenge might be eased by systematic attention to explanatory factors in relation to the surface characteristics, using specific tests for this purpose. Word identification tasks tap speech perception skills; repetition of short versus long strings of nonsense syllables permits observation of phonological memory and phonological planning skills; and standard maximum performance tests provide considerable information about speech motor control. What are the potential or actual clinical implications of this work? Children with SSDs should receive comprehensive assessments of their phonological processing, phonological planning and motor planning skills frequently, alongside examinations of their error patterns in connected speech. Such assessments will serve to identify the child's primary challenges currently and as they change over developmental time.

Speech sound development of young Dutch children with a developmental language disorder: A complex matter.

BACKGROUND: Approximately 50% of all young children with a developmental language disorder (DLD) also have problems with speech production. Research on speech sound development and clinical diagnostics of speech production difficulties focuses mostly on accuracy; it relates children's phonological realizations to adult models. Contrarily to these relational analyses, independent analyses indicate the sounds and structures children produce irrespective of accuracy. Such analyses are likely to provide more insight into a child's phonological strengths and limitations, and may thus provide better leads for treatment. AIMS: Ram (1) To contribute to a more comprehensive overview of the speech sound development of young Dutch children with DLD by including independent and relational analyses, (2) to develop an independent measure to assess these children's speech production capacities; and (3) to examine the relation between independent and relational speech production measures for children with DLD. METHODS & PROCEDURES: We describe the syllable structures and sounds of words elicited in two picture-naming tasks of 82 children with DLD and speech production difficulties between ages 2;7 and 6;8. The children were divided into four age groups to examine developmental patterns in a cross-sectional manner. Overviews of the children's productions on both independent and relational measures are provided. We conducted a Spearman correlation analysis to examine the relation between accuracy and independent measures. OUTCOMES & RESULTS: The overviews show these children are able to produce a greater variety of syllable structures and consonants irrespective of target positions than they can produce correctly in targets. This is especially true for children below the age of 4;5. The data indicate that children with DLD have difficulty with the production of clusters, fricatives, liquids and the velar nasal (/ŋ/). Based on existing literature and our results, we designed a Dutch version of an independent measure of word complexity, originally designed for English (word complexity measure-WCM) in which word productions receive points for specific word, syllable and sound characteristics, irrespective of accuracy. We found a strong positive correlation between accuracy scores and scores on this independent measure. CONCLUSIONS & IMPLICATIONS: The results indicate that the use of independent measures, including the proposed WCM, complement traditional relational measures by indicating which sounds and syllable structures a child can produce (irrespective of correctness). Therefore, the proposed measure can be used to monitor the speech sound development of children with DLD and to better identify treatment goals, in combination with existing relational measures. WHAT THIS PAPER ADDS: What is already known on the subject Speech production skills can be assessed in different ways: (1) using analyses indicating the structures and sounds a child produces irrespective of accuracy, that is, performance analyses; and (2) using analyses indicating how the productions of a child relate to the adult targets, that is, accuracy analyses. In scientific research as well as in clinical practice the focus is most often on accuracy analyses. As a consequence, we do not know if children who do not improve in accuracy scores, improve in other phonological aspects that are not captured in these analyses, but can be captured by performance analyses. What this study adds to the existing knowledge The overviews show these children are able to produce a greater variety of syllable structures and consonants irrespective of target positions than they can produce correctly in targets. Consequently, adding performance analyses to existing accuracy analyses provides a more complete picture of a child's speech sound development. What are the potential or actual clinical implications of this work? We propose a Dutch version of a WCM, originally designed for English, in which word productions receive points for word structures, syllable structures and sounds, irrespective of accuracy. This measure may be used by Dutch clinicians to monitor the speech sound development of children with DLD and to formulate better treatment goals, in addition to accuracy measures that are already used.

Deep learning fusion framework for automated coronary artery disease detection using raw heart sound signals.

One of the most common cardiovascular diseases is coronary artery disease (CAD). Thus, it is crucial for early CAD diagnosis to control disease progression. Computer-aided CAD detection often converts heart sounds into graphics for analysis. However, this method relies heavily on the subjective experience of experts. Therefore, in this study, we proposed a method for CAD detection using raw heart sound signals by constructing a fusion framework with two CAD detection models: a multidomain feature model and a medical multidomain feature fusion model. We collected heart sound signal datasets from 400 participants, extracting 206 multidomain features and 126 medical multidomain features. The designed framework fused the same one-dimensional deep learning features with different multidomain features for CAD detection. The experimental results showed that the multidomain feature model and the medical multidomain feature fusion model achieved areas under the curve (AUC) of 94.7 % and 92.7 %, respectively, demonstrating the effectiveness of the fusion framework in integrating one-dimensional and cross-domain heart sound features through deep learning algorithms, providing an effective solution for noninvasive CAD detection.

Simultaneous laser ultrasonic measurement of sound velocities and thickness of plates using combined mode local acoustic spectroscopy.

Standard ultrasonic thickness measurements require the sound velocity of the sample to be known and vice versa. We present a method, which we have termed combined mode local acoustic spectroscopy (CoMLAS) for simultaneously determining a plate's thickness and sound velocities without requiring such a priori knowledge. It is based on a combination of three guided wave modes sustained by a plate at discrete frequencies, which we generate and detect using laser ultrasound. We use a pulsed laser that is shaped into a periodic line pattern on the sample's surface to generate elastic waves and measure the response at the pattern's center with a vibrometer. The surface acoustic wave mode produces an interference peak in the response spectrum at the frequency corresponding to the wavelength matching the pattern line spacing. By limiting the total size of the excitation pattern, we can simultaneously generate two zero-group-velocity plate resonances, providing two additional peaks in the spectrum. The plate's local thickness and longitudinal and transverse sound velocities are calculated from the peak frequencies. We demonstrate the feasibility of CoMLAS on steel and aluminum sheets with a thickness of around 2mm by resolving thickness steps and temperature-induced changes in the sound velocities. Using numerical simulations and control experiments, we provide insights into the method's accuracy and limitations. The choice of excitation pattern, the method's sensitivity, and the influence of sample inhomogeneity and anisotropy are discussed. CoMLAS does not require scanning mechanics and provides local plate properties. The results shown are achieved with low-energy lasers and signal averaging. Considerations on signal-to-noise ratio indicate that a realization with available lasers of higher energy will enable single-shot measurements. This qualifies the method for use on moving samples in an industrial environment.

Bridging auditory perception and natural language processing with semantically informed deep neural networks.

Sound recognition is effortless for humans but poses a significant challenge for artificial hearing systems. Deep neural networks (DNNs), especially convolutional neural networks (CNNs), have recently surpassed traditional machine learning in sound classification. However, current DNNs map sounds to labels using binary categorical variables, neglecting the semantic relations between labels. Cognitive neuroscience research suggests that human listeners exploit such semantic information besides acoustic cues. Hence, our hypothesis is that incorporating semantic information improves DNN's sound recognition performance, emulating human behaviour. In our approach, sound recognition is framed as a regression problem, with CNNs trained to map spectrograms to continuous semantic representations from NLP models (Word2Vec, BERT, and CLAP text encoder). Two DNN types were trained: semDNN with continuous embeddings and catDNN with categorical labels, both with a dataset extracted from a collection of 388,211 sounds enriched with semantic descriptions. Evaluations across four external datasets, confirmed the superiority of semantic labeling from semDNN compared to catDNN, preserving higher-level relations. Importantly, an analysis of human similarity ratings for natural sounds, showed that semDNN approximated human listener behaviour better than catDNN, other DNNs, and NLP models. Our work contributes to understanding the role of semantics in sound recognition, bridging the gap between artificial systems and human auditory perception.

Multi-angle speed-of-sound imaging with sparse sampling to characterize medical tissue properties.

Medical Speed-of-sound (SoS) imaging, which can characterize medical tissue properties better by quantifying their different SoS, is an effective imaging method compared with conventional B-mode ultrasound imaging. As a commonly used diagnostic instrument, a hand-held array probe features convenient and quick inspection. However, artifacts will occur in the single-angle SoS imaging, resulting in indistinguishable tissue boundaries. In order to build a high-quality SoS image, a number of raw data are needed, which will bring difficulties to data storage and processing. Compressed sensing (CS) theory offers theoretical support to the feasibility that a sparse signal can be rebuilt with random but less sampling data. In this study, we proposed an SoS reconstruction method based on CS theory to process signals obtained from a hand-held linear array probe with a passive reflector positioned on the opposite side. The SoS reconstruction method consists of three parts. Firstly, a sparse transform basis is selected appropriately for a sparse representation of the original signal. Then, considering the mathematical principles of SoS imaging, the ray-length matrix is used as a sparse measurement matrix to observe the original signal, which represents the length of the acoustic propagation path. Finally, the orthogonal matching pursuit algorithm is introduced for image reconstruction. The experimental result of the phantom proves that SoS imaging can clearly distinguish tissues that show similar echogenicity in B-mode ultrasound imaging. The simulation and experimental results show that our proposed method holds promising potential for reconstructing precision SoS images with fewer signal samplings, transmission, and storage.

DIFFERENTIAL CONTRIBUTIONS OF THE SPECTRO-TEMPORAL AND VOCAL CHARACTERISTICS OF AUDITORY PSEUDOWORDS TO MULTIPLE SOUND-SYMBOLIC MAPPINGS.

Sound symbolism, the idea that the sound of a word alone can convey its meaning, is often studied using auditory pseudowords. For example, people reliably assign the auditory pseudowords "bouba" and "kiki" to rounded and pointed shapes, respectively. Previously we showed that representational dissimilarity matrices (RDMs) of the shape ratings of auditory pseudowords correlated significantly with RDMs of acoustic parameters reflecting spectro-temporal variations; the ratings also correlated significantly with voice quality features. Here, participants rated auditory pseudowords on scales representing categorical opposites across seven meaning domains, including shape. Examination of the relationships of the perceptual ratings to spectro-temporal and vocal parameters of the pseudowords essentially replicated our previous findings for shape while varying patterns emerged for the other domains. Thus, the spectro-temporal and vocal properties of spoken pseudowords contribute differentially to sound-symbolic mapping depending on the meaning domain.

Toward Wearables for Bruxism Detection: Voluntary Oral Behaviors Sound Recorded Across the Head Depend on Transducer Placement.

OBJECTIVES: Bruxism is a parafunctional orofacial behavior. For diagnosis, wearable devices that use sounds as biomarkers can be applied to provide the necessary information. Human beings emit various verbal and nonverbal sounds, making it challenging to identify bruxism-induced sounds. We wanted to investigate whether the acoustic emissions of different oral behaviors have distinctive characteristics and if the placement of the transducer has an impact on recording the sound signals. MATERIAL AND METHODS: Sounds from five oral behaviors were investigated: jaw clenching, teeth grinding, reading, eating, and drinking. Eight transducers were used; six were attached to the temporal, frontal, and zygomatic bones with the aid of medical tape, and two were integrated into two commercial earphones. The data from 15 participants were analyzed using time-domain energy, spectral flux, and zero crossing rate (ZCR). RESULTS: In summary, all oral behaviors showed distinct characteristic features except jaw clenching, though there was a peak in the recording, possibly due to tooth tapping, before its expected onset. For teeth grinding, the transducer placement did not have a significant impact (p > 0.05) based on energy, spectral flux, and ZCR. For jaw clenching, the transducer placement had an impact with regard to spectral flux (p < 0.01). For reading and eating, the transducer placement had a significant impact with regard to energy (p < 0.05 for reading, p < 0.01 for eating), spectral flux (p < 0.001 for reading, p < 0.01 for eating), and ZCR (p < 0.001 for both reading and eating). For drinking, the transducer placement only had a significant impact with regard to ZCR (p < 0.01). CONCLUSIONS: We were able to record the sounds of various oral behaviors from different locations on the head. However, the ears were an advantageous location to place the transducer, since they could compensate for various head movements and ear devices are socially tolerable.

Single session of direction-specific training using auditory cues improves anticipatory postural adjustments to lateral perturbations.

When exposed to a predictable external perturbation, humans typically generate anticipatory postural adjustments (APAs) to minimize potential body disturbance. After a single session of training, individuals demonstrated the ability to rely solely on an auditory cue to elicit appropriate APAs in response to an external postural perturbation. However, whether the generation of APAs requires directional specific training remains unclear. The aim of this study was to assess whether directional-specific training with auditory cues is necessary for the generation of appropriate APA responses. Ten young adults were exposed to external perturbations targeting either their left or right shoulders, with or without an auditory cue prior to the physical impact. Electromyography (EMG) activities of sixteen trunk and leg muscles and center-of-pressure (COP) displacements were recorded and analyzed during the anticipatory and compensatory phases of postural control. Outcome measures included the latencies and integrals of muscle activities, COP displacements, and indices of co-contraction and reciprocal activation of muscles. The results revealed that, after training with right-side perturbations accompanied by an auditory cue, young adults exhibited earlier and more efficient APA responses to right-side perturbations relying only on the auditory cue. Additionally, they displayed earlier APA responses in some muscles to left-side perturbations, although these responses were less efficient. Our findings suggest that young adults could generate effective APAs to external perturbations relying on an auditory cue after a single training session; however, these responses were directional specific.

The role of cardiac acoustic biomarkers in monitoring patients with heart failure: A systematic literature review.

Heart failure (HF) creates a considerable clinical, humanistic and economic burden on patients and caregivers as well as on healthcare systems. To attenuate the significant burden of HF, there is a need for enhanced management of patients with HF. The use of digital tools for remote non-invasive monitoring of heart parameters is gaining traction, and cardiac acoustic biomarkers (CABs) have been proposed as a complementary set of measures to assess heart function alongside traditional methods such as electrocardiogram and echocardiography. We conducted a systematic literature review to evaluate associations between CABs and HF outcomes. Embase and MEDLINE databases were searched for recent studies published between 2013 and 2023 that evaluated CABs in patients with HF. Additional grey literature (i.e., conference, congress and pre-print publications from January 2021 to May 2023) searches were included. Two reviewers independently examined all articles; a third resolved conflicts. Data were extracted from articles meeting inclusion criteria. Extracted studies underwent quality and bias assessments using the Joanna Briggs Institute (JBI) critical appraisal tools. In total, 3074 records were screened, 73 full-text articles were assessed for eligibility and 27 publications were included. Third heart sound (S3) and electromechanical activation time (EMAT) were the CABs most often reported in the literature for monitoring HF. Fifteen publications discussed changes in S3 characteristics and its role in HF detection or outcomes: six studies highlighted S3 assessment among various groups of patients with HF; four studies evaluated the strength or amplitude of S3 with clinical outcomes; five studies assessed the relationship between S3 presence and clinical outcomes; and one study assessed both S3 presence and amplitude in relation to HF clinical outcomes. Eleven publications reported on EMAT and its derivatives: five studies on the relationship between EMAT and HF and six studies on the association of EMAT and HF clinical outcomes. Studies reporting the first and fourth heart sound, left ventricular ejection time and systolic dysfunction index were limited. Published literature supported S3 and EMAT as robust CAB measures in HF that may have value in remote clinical monitoring and management of patients with HF. Additional studies designed to test the predictive power of these CABs, and others less well-characterized, are needed. This work was funded by Astellas Pharma Inc.

Memory Load Test - A Concept for Cognitive Reserve Evaluation with Auditory Perception.

<b>Introduction:</b> Auditory scene analysis refers to the system through which the auditory system distinguishes distinct auditory events and sources to create meaningful auditory information. The exact number of directly perceived auditory stimuli is unknown, studies suggest it may range from 3 to 5. This number differs among individuals, and potentially may indirectly indicate the ability to store and process the complex information, related to the memory load, which is combined with human cognitive processes.<b>Aim:</b> This study aims to further identify and quantify the number of sounds that can be perceived simultaneously in a complex auditory environment.<b>Material and methods:</b> Participants were presented with structured acoustic recordings and were asked to identify the exact number of targeted stimuli heard throughout the test. The experiment was designed to assess the auditory load and determine the maximum number of auditory stimuli that a healthy human can perceive at once.<b>Results:</b> Our study showed that on average, participants could identify up to three sounds at once with accuracy of responses declining progressively for four sounds or more.<b>Conclusions:</b> This study aimed to investigate the human capacity to detect and identify multiple sound signals simultaneously in a noisy environment. By understanding this ability, we sought to assess cognitive reserve in individuals. Our objective was to determine if auditory load could serve as a diagnostic tool for cognitive evaluation. We believe that further research will establish the validity of this approach, and we anticipate that it is only a matter of time before it becomes a viable method for assessing cognitive function.

Pulsed sounds caused by internal oxygen transport during photosynthesis in the seagrass Halophila ovalis.

Oxygen bubbles that leak from seagrass blades during photosynthesis have been hypothesized to cause cavitation sounds in aquatic plants. Here we investigate low-amplitude sounds with regular pulse rates produced during photosynthesis in seagrass beds of Halophila ovalis (Qitou Bay, Penghu islands and Cigu Lagoon, Taiwan). Sound pulses appear in the morning when illumination exceeds 10,000 Lux, peak at midday and decrease in midafternoon on a sunny day. Frequencies peak between 1 to 4 kHz, durations range between ca. 1.8 to 4.8 ms, and sound pressure level 1 cm from the bed is 105.4 ± 0.5 dB re 1 µPa (1100 h on a cloudy day). Sounds attenuate rapidly with distance, disappearing beyond 15 cm. Blocking sunlight or administering herbicide stops ongoing sounds. Gas bubbles are not typically seen during sound production ruling out cavitation, and external force (scissor cutting or plant pressed against the substrate) applied to the patch, leaves, petioles, or rhizomes generally increases pulse rate. We suggest sound emission is caused by internal oxygen transport through pores in diaphragms (a whistle mechanism) at the leaf base and nodes of the rhizome.

Electrical-Modulated Flexible Acoustic Metamaterial: Enhancing Low-Frequency Absorption via an Ionic Electroactive Polymer.

The growing concern over low-frequency noise pollution resulting from global industrialization has posed substantial challenges in noise attenuation. However, conventional acoustic metamaterials, with fixed geometries, offer limited flexibility in the frequency range adjustment once constructed. This research unveiled the promising potential of ionic electroactive polymers, particularly ionic polymer-metal composites (IPMCs), as a superior candidate to design tunable acoustic metamaterial due to its bidirectional energy conversion capabilities. The previously perceived limitations of the IPMC, including slow reaction and high energy expenditure, owning to its inherent sluggish intermediary ionic mass transport process, were astutely leveraged to expedite the attenuation of low-frequency sound energy. Both our experimental and simulation results elucidated that the IPMC can generate voltage potentials in response to acoustic pressure at frequencies significantly higher than those previously established. In addition, the peak absorption frequency can be effectively shifted by up to 45.7% with the application of a 4 V voltage. By further integration with a microperforated panel (MPP) structure, the developed metamaterial absorbers can achieve complete sound absorption, which was continuously tunable under minimal voltage stimulation across a wide frequency spectrum. In addition, a microslit structure IPMC metamaterial absorber was designed to realize modulation of the perforation rate, and the absorption peak can be shifted by up to 79.2%. These findings signify a pioneering application of ionic intelligent materials and may pave the way for further innovations of tunable low-frequency acoustic structures, ultimately advancing the pragmatic deployment of both soft intelligent materials and acoustic metamaterials.