Tongue Clicks Research Articles

Distributional and Acoustic Characteristics of Filler Particles in German with Consideration of Forensic-Phonetic Aspects

In this study, we investigate the use of the filler particles (FPs) uh, um, hm, as well as glottal FPs and tongue clicks of 100 male native German speakers in a corpus of spontaneous speech. For this purpose, the frequency distribution, FP duration, duration of pauses surrounding FPs, voice quality of FPs, and their vowel quality are investigated in two conditions, namely, normal speech and Lombard speech. Speaker-specific patterns are investigated on the basis of twelve sample speakers. Our results show that tongue clicks and glottal FPs are as common as typically described FPs, and should be a part of disfluency research. Moreover, the frequency of uh, um, and hm decreases in the Lombard condition while the opposite is found for tongue clicks. Furthermore, along with the usual F1 increase, a considerable reduction in vowel space is found in the Lombard condition for the vowels in uh and um. A high degree of within- and between-speaker variation is found on the individual speaker level.

Caudal auricular muscle variations and the evolution of echolocation behavior in pteropodid bats.

Among bats, rhinolophoids and yangochiropterans, but not pteropodids, exhibit laryngeal echolocation. Although Rousettus has been regarded as the only pteropodid capable of echolocation using tongue clicks, recent evidence suggests that other species of pteropodids are also capable of echolocation using wing clicks. Studies on laryngeal echolocators suggest that delicate ear movements are essential for the echolocation behavior of bats and that the cervicoauricularis muscles play a critical role in such ear movements. In this study, we observed the gross anatomy of cervicoauricularis muscles in three species of pteropodids (Cynopterus sphinx, Eonycteris spelaea, and Rousettus leschenaultii) to examine whether ear muscle anatomy varies among pteropodids with different echolocation types and between pteropodids and laryngeal echolocating bats. We found that M. cervicoauricularis profundus originates from the nuchal crest in tongue-click echolocators (R. leschenaultii) and from the midline in wing-click echolocators (C. sphinx and E. spelaea). In general, tongue-click echolocation using high click rates is considered to be more sophisticated in terms of sonar performance than wing-click echolocation. M. cervicoauricularis profundus originating from the nuchal crest (CPNC) is not common in non-bat laurasiatherian mammals, but can be found in laryngeal echolocating bats. As it pulls the ear pinna caudally in the horizontal plane and increases the access to sound, CPNC found in R. leschenaultii and laryngeal echolocating bats may be a key characteristic of the sophisticated active echolocation behavior of bats.

Coevolution of motor cortex and behavioral specializations associated with flight and echolocation in bats

Bats have evolved behavioral specializations that are unique among mammals, including self-propelled flight and echolocation. However, areas of motor cortex that are critical in the generation and fine control of these unique behaviors have never been fully characterized in any bat species, despite the fact that bats compose ∼25% of extant mammalian species. Using intracortical microstimulation, we examined the organization of motor cortex in Egyptian fruit bats (Rousettus aegyptiacus), a species that has evolved a novel form of tongue-based echolocation.1,2 We found that movement representations includean enlarged tongue region containing discrete subregions devoted to generating distinct tongue movement types, consistent with their behavioral specialization generating active sonar using tongue clicks. This magnification of the tongue in motor cortex is comparable to the enlargement of somatosensory representations in species with sensory specializations.3-5 We also found a novel degree of coactivation between the forelimbs and hindlimbs, both of which are involved in altering the shape and tension of wing membranes during flight. Together, these findings suggest that the organization of motor cortex has coevolved with peripheral morphology in bats to support the unique motor demands of flight and echolocation.

Discrimination of 2D wall textures by passive echolocation for different reflected-to-direct level difference configurations.

In this work, we study people’s ability to discriminate between different 2D textures of walls by passive listening to a pre-recorded tongue click in an auralized echolocation scenario. In addition, the impact of artificially enhancing the early reflection magnitude by 6dB and of removing the direct component while equalizing the loudness was investigated. Listening test results for different textures, ranging from a flat wall to a staircase, were assessed using a 2 Alternative-Forced-Choice (2AFC) method, in which 14 sighted, untrained participants were indicating 2 equally perceived stimuli out of 3 presented stimuli. The average performance of the listening subjects to discriminate between different textures was found to be significantly higher for walls at 5m distance, without overlap between the reflected and direct sound, compared to the same walls at 0.8m distance. Enhancing the reflections as well as removing the direct sound were found to be beneficial to differentiate textures. This finding highlights the importance of forward masking in the discrimination process. The overall texture discriminability was found to be larger for the walls reflecting with a higher spectral coloration.

Role of Dendritic Cells in Post-Extraction Alveolar Bone Healing

Due to the extent humans rely on vision, sight restoration approaches are the predominant treatment option considered for optic neuropathy patients with vision loss. This trend is reflected in the wealth of research on sight restoration procedures. Patients with irreversible vision loss are left with limited treatment options due to the lack of research on alternative therapeutics and the prevalence of misdiagnosis (Jay, 2016; Weerasinghe & Lueck, 2016). Compensatory plasticity holds that auditory input can colonize the available cortical space in the visually deprived brain. The resulting enhancements in auditory cognition can be capitalized on by auditory-based rehabilitative tools. Sensory substitution devices have allowed visually deprived individuals to hear ‘colours’ and ‘shapes’, perceive their surroundings (O. Collignon, Champoux, Voss, & Lepore, 2011; Striem-Amit, Guendelman, & Amedi, 2012) and even read ‘written’ letters (Striem-Amit, Cohen, Dehaene, & Amedi, 2012) using soundscapes. VD echolocators navigate through daily obstacles using tongue clicks (Arnott, Thaler, Milne, Kish, & Goodale, 2013; A. J. Kolarik, Cirstea, Pardhan, & Moore, 2014; A. J. Kolarik, Scarfe, Moore, & Pardhan, 2017; Papadopoulos, Edwards, Rowan, & Allen, 2011; Teng, Puri, & Whitney, 2012; Teng & Whitney, 2011; Thaler, Arnott, & Goodale, 2011). Many higher order visual regions retain their functional specialization and adapt to auditory input from soundscapes or tongue clicks (O. Collignon, Lassonde, Lepore, Bastien, & Veraart, 2006; A. J. Kolarik et al., 2014; Striem-Amit & Amedi, 2014; Striem-Amit, Cohen, et al., 2012; Thaler et al., 2011). Due to the interaction between critical periods and plasticity, the therapeutic value of rehabilitative tools can vary with age of onset. Plasticity-induced cognitive enhancements from lack of visual stimulation during critical periods may underlie the greater efficacy of auditory-based rehabilitation for patients with early vision loss (Voss, 2019). Later vision loss improved the clinical outcome of sight restoration procedures. The addition of neuromodulators into other rehabilitative efforts may augment their therapeutic potential by promoting plasticity (Voss et al., 2016). While sight restoration may be the ideal rehabilitative procedure for optic neuropathy patients, auditory-based rehabilitative tools are valuable and underutilized treatment options when vision cannot be recovered.

INTRODUCTION TO HUMAN ECHOLOCATION: A WAY OF SEEING THE WORLD EVEN FOR VISUALLY IMPAIRED PEOPLE

An overview is given of the current knowledge on the perception of the daily environment by visually impaired people by means of echolocation. Passive echolocation is discussed, as well as active echolocation based on tongue click and hiss sounds.

Detection and classification of human-produced nonverbal audio events

Audio wearable devices, or hearables, are becoming an increasingly popular consumer product. Some of these hearables contain an in-ear microphone to capture audio signals inside the user’s occluded earcanal. Mainly, the microphone is used to pick up speech in noisy environments, but it can also capture other signals, such as nonverbal events that could be used to interact with the device or a computer. Teeth or tongue clicking could be used to interact with a device in a discreet manner, and coughing or throat-clearing sounds could be used to monitor the health of a user. In this paper, 10 human produced nonverbal audio events are detected and classified in real-time with a classifier using the Bag-of-Audio-Words algorithm. To build this algorithm, different clustering and classification methods are compared. Mel-Frequency Cepstral Coefficient features are used alongside Auditory-inspired Amplitude Modulation features and Per-Channel Energy Normalization features. To combine the different features, concatenation performance at the input level and at the histogram level is compared. The real-time detector is built using the detection by classification technique, classifying on a 400 ms window with 75% overlap. The detector is tested in a controlled noisy environment on 10 subjects. The classifier had a sensitivity of 81.5% while the detector using the same classifier had a sensitivity of 69.9% in a quiet environment.

Retinal Ganglion Cell Topography and Spatial Resolving Power in Echolocating and Non-Echolocating Bats

Bats are nocturnal mammals known for their ability to echolocate, yet all bats can see, and most bats of the family Pteropodidae (fruit bats) do not echolocate – instead they rely mainly on vision and olfaction to forage. We investigated whether echolocating bats, given their limited reliance on vision, have poorer spatial resolving power (SRP) than pteropodids and whether tongue click echolocating fruit bats differ from non-echolocating fruit bats in terms of visual performance. We compared the number and distribution of retinal ganglion cells (RGCs) as well as the maximum anatomical SRP derived from these distributions in 4 species of bats: Myotis daubentonii, a laryngeal echolocating bat from the family Vespertilionidae, Rousettus aegyptiacus, a tongue clicking echolocating bat from the family Pteropodidae, and Pteropus alecto and P. poliocephalus, 2 non-echolocating bats (also from the Pteropodidae). We find that all 3 pteropodids have a similar number (≈200,000 cells) and distribution of RGCs and a similar maximum SRP (≈4 cycles/degree). M. daubentonii has fewer (∼6,000 cells) and sparser RGCs than the pteropodids and thus a significantly lower SRP (0.6 cycles/degree). M. daubentonii also differs in terms of the distribution of RGCs by having a unique dorsal area of specialization in the retina. Our findings are consistent with the existing literature and suggest that M. daubentonii likely only uses vision for orientation, while for pteropodids vision is also important for foraging.

The vocal repertoire of an African colobine, Colobus angolensis ruwenzorii: a multi-level society compared to congeners in stable groups

Abstract Vocal behaviour offers a window into understanding the social life and evolution of animals. Colobine monkeys show great interspecific and interpopulation variation in their social organization and behaviour. Recent research has shown that Rwenzori Angolan colobus (Colobus angolensis ruwenzorii) differ substantially from other black-and-white colobus in forming a multi-level society. No previous research has been conducted on the communication of C. a. ruwenzorii, but the social complexity hypothesis for communication suggests that more complex societies should evolve more complex communication repertoires. Our objective was to catalogue the vocal repertoire of C. a. ruwenzorii at Nabugabo, Uganda, and to compare it with the data available on congeners regarding intergroup tolerance, vocal repertoire size, and acoustic and behavioural features of vocal communication. Vocalizations were subject to spectrographic and behavioural analysis, and a descriptive analysis of each vocalization type was made. The influence of a few environmental and social factors on calling rates was also examined. We describe five vocalizations (i.e., the snort, roar, squeak, scream and pok) and one non-vocal signal (i.e., the tongue click) in this subspecies and their contexts. Distinct alarm calls are made for dogs, and these are given more often near the edge of the forest where humans frequent. We did not find that C. a. ruwenzorii showed a greater vocal repertoire than C. guereza or C. polykomos, which do not live in multi-level societies. Further, preliminary data do not indicate greater calling rates in larger core units of C. a. ruwenzorii compared to smaller units. These findings support the view that these primates’ vocalizations tend to be relatively conserved despite large differences in social organization.

Хоровое письмо Карлхайнца Штокхаузена в гепталогии «Licht»

The article is devoted to the phenomenon of Karlheinz Stockhausen’s choral writing in his large- scale opera project Licht. The musical composition’s religious-philosophical basis, which initiates the transformation of the opera theater into a quasi-temple space, leads to the reinforcement of the dramaturgical role of choral music, which manifests itself in the intensification of the presence of the chorus in the opera project (massive choral scenes appear in all the heptalogy’s operas) and in the expansion of its function. The diversity of the types of exposition of the musical material, nonetheless, makes it possible to disclose as a general tendency the aspiration towards choral stereophony, both in the situation of a multichannel reproduction of previously recorded choral material (Unsichtbare Chöre) and in live performance (practically all the choral scenes in the heptalogy). Special attention is given to analysis of the verbal basis of the choral scenes. Along with incorporating his own texts, Stckhausen turns to the sacred literature of Christianity, Judaism, Hinduism and Islam. Combination of poly-lingual texts in different styles in the conclusive scene of the Hoch-Zeiten symbolizes the spiritual relatedness of all of humanity. An important technical resource is the use of elements of phonemic composition, exerting direct influence on the choral timbres. The composition’s timbral side attracts attention to it by its connection together of elements of vocal technique already used by Stockhausen in his preceding compositions (4 modifications of vocal tremolo, glissando, phonic intonating, Sprechgesang, singing while inhaling, tongue clicks, etc.) with special techniques typical particularly for the score of Licht. The latter include “color noise” (“fabriges Rauschen”), yodeling and a “kissing sound” (“Kußgeräusche”). The organic quality of such a complex is guaranteed by the unity of the conception of Stockhausen’s heptalogy, which the exerted influence not only on the opera cycle’s compositional technique, but also on its scenography and dramaturgical solutions. Keywords: Karlheinz Stockhausen, heptalogy Licht, contemporary choral music, texture, stereophony, choral timbre, music and the word, phonemic composition.

Reinforcement of the larynx and trachea in echolocating and non-echolocating bats.

The synchronization of flight mechanics with respiration and echolocation call emission by bats, while economizing these behaviors, presumably puts compressive loads on the cartilaginous rings that hold open the respiratory tract. Previous work has shown that during postnatal development of Artibeus jamaicensis (Phyllostomidae), the onset of adult echolocation call emission rate coincides with calcification of the larynx, and the development of flight coincides with tracheal ring calcification. In the present study, I assessed the level of reinforcement of the respiratory system in 13 bat species representing six families that use stereotypical modes of echolocation (i.e. duty cycle % and intensity). Using computed tomography, the degree of mineralization or ossification of the tracheal rings, cricoid, thyroid and arytenoid cartilages were determined for non-echolocators, tongue clicking, low-duty cycle low-intensity, low-duty cycle high-intensity, and high-duty cycle high-intensity echolocating bats. While all bats had evidence of cervical tracheal ring mineralization, about half the species had evidence of thoracic tracheal ring calcification. Larger bats (Phyllostomus hastatus and Pterpodidae sp.) exhibited more extensive tracheal ring mineralization, suggesting an underlying cause independent of laryngeal echolocation. Within most of the laryngeally echolocating species, the degree of mineralization or ossification of the larynx was dependent on the mode of echolocation system used. Low-duty cycle low-intensity bats had extensively mineralized cricoids, and zero to very minor mineralization of the thyroids and arytenoids. Low-duty cycle high-intensity bats had extensively mineralized cricoids, and patches of thyroid and arytenoid mineralization. The high-duty cycle high-intensity rhinolophids and hipposiderid had extensively ossified cricoids, large patches of ossification on the thyroids, and heavily ossified arytenoids. The high-duty cycle high-intensity echolocator, Pteronotus parnellii, had mineralization patterns and laryngeal morphology very similar to the other low-duty cycle high-intensity mormoopid species, perhaps suggesting relatively recent evolution of high-duty cycle echolocation in P. parnellii compared with the Old World high-duty cycle echolocators (Rhinolophidae and Hipposideridae). All laryngeal echolocators exhibited mineralized or ossified lateral expansions of the cricoid for articulation with the inferior horn of the thyroid, these were most prominent in the high-duty cycle high-intensity rhinolophids and hipposiderid, and least prominent in the low-duty cycle low-intensity echolocators. The non-laryngeal echolocators had extensively ossified cricoid and thyroid cartilages, and no evidence of mineralization/ossification of the arytenoids or lateral expansions of the cricoid. While the non-echolocators had extensive ossification of the larynx, it was inconsistent with that seen in the laryngeal echolocators.

Ambiguity function analysis of human echolocator waveform by using gammatone filter processing

Human echolocation is a technique used by small group of people (normally blind persons) to observe their surrounding via emitting an active signal (usually tongue click) and analyse the return echo. This skill allows them to navigate safely by ‘seeing through sound’. Remarkable performances upon echolocating have attracted scholars’ attention from multidiscipline field including psychophysical and engineering. Study of waveform diversity has reported the signal is wideband, consisting of multiple frequency components with exponential decay factor that probably made up the entire unique signal. As such, wideband perspective is considered during ambiguity function analysis using wide-band ambiguity function method. The waveform analysis continues and reported optimum autocorrelation function is achieved by adopting a bio-inspired technique, which incorporated gammatone-filter processing. It will be interesting to synthesise the waveform using gammatone-filter approaches prior to relay it into ambiguity function process for analysis. Therefore, it is worth to explore its output results in this paper, which hold new findings that may help to understand how these humans achieve an optimum performance upon echolocating including ambiguity function characteristic. Thus, the new knowledge explored in this paper could be beneficial in emerging concept for new development in radar and sonar system application in near future.

Human echolocation: 2D shape discrimination using features extracted from acoustic echoes

Some blind humans have developed the ability to perceive their silent surrounding by using echolocation based on tongue clicks. Past research has also shown that blind echolocators can use information gained from multiple echoic ‘views’, provided through head movements, to successfully identify 2D shapes. Here, echo features that might be used by blind humans to discriminate 2D shapes are investigated. Echoes from four shapes are collected with a custom-built acoustic radar and various features are extracted. By piecing together individual features across the measurement plane, it is found that total power and spectral centroid are two salient features for shape discrimination from multiple echoic views.

Human Echolocation for Target Detection Is More Accurate With Emissions Containing Higher Spectral Frequencies, and This Is Explained by Echo Intensity.

Humans can learn to use acoustic echoes to detect and classify objects. Echolocators typically use tongue clicks to induce these echoes, and there is some evidence that higher spectral frequency content of an echolocator’s tongue click is associated with better echolocation performance. This may be explained by the intensity of the echoes. The current study tested experimentally (a) if emissions with higher spectral frequencies lead to better performance for target detection, and (b) if this is mediated by echo intensity. Participants listened to sound recordings that contained an emission and sometimes an echo from an object. The peak spectral frequency of the emission was varied between 3.5 and 4.5 kHz. Participants judged whether they heard the object in these recordings and did the same under conditions in which the intensity of the echoes had been digitally equated. Participants performed better using emissions with higher spectral frequencies, but this advantage was eliminated when the intensity of the echoes was equated. These results demonstrate that emissions with higher spectral frequencies can benefit echolocation performance in conditions where they lead to an increase in echo intensity. The findings suggest that people who train to echolocate should be instructed to make emissions (e.g. mouth clicks) with higher spectral frequency content.

Acoustic Properties of Tongue Clicks used for Human Echolocation

In active human echolocation, it is common for visually impaired persons to produce tongue click signals for extracting information from the physical environment around them. The purpose of this paper is to provide a comprehensive dataset of original detailed experimental data on human tongue clicks. The methods used for analysis are described in order to encourage further work to complement the data, which is available online and open for contributions. Series of six different click signals have been recorded from blind persons in an anechoic room. The different click signals all resemble damped oscillations and have in common that the dominant frequency content is located between 1,000 Hz and 8,000 Hz. The standard deviation in click series of the broadband click sound level is between 2.2 and 4.3 dB. The total duration of the clicks, which is mainly determined by the drop-time, ranges between 2.0 ms and 10.0 ms, for a 20 dB decay range. Average standard deviations of 57% in rise-time and 32% in drop-time have been found. The horizontal and vertical directivity of the tongue clicks show a close agreement with literature data from speech signals, but click signals are generally more directive. The minimum and maximum deviations in the 1/3 octave bands from 1,250 Hz to 4,000 Hz are less than 6 dB, for 0 to 120 deg. azimuth, and for –27 to 127 deg. elevation.

Bio‐inspired signal detection mechanism for tongue click waveform used in human echolocation

Human echolocation is the ability of an individual (which is often a blind person) to use his/her signal such as sound from tongue clicks to perceive the surrounding. Basically this requires the person to listen and analyse to the return echo of the tongue clicks. The main characteristics of the tongue click signal waveform have been reported, however the fundamental principle on a person's ability to identify his/her own signal is still vague. The possible detection mechanism of the tongue click signal waveform used in human echolocation technique is discussed and imitated it as artificial detection system. The proposed mechanism which is based on human hearing process in synthesising the signal illustrates that the detection performance is improved as compared to the detection performance by the traditional matched filtering technique. The findings of this Letter create new potential for the development of any artificial human echolocator system, sensor systems like radar and sonar as well as applications inspired by human echolocation miracles.

Human echolocation: waveform analysis of tongue clicks

Some blind individuals have the ability to detect and classify objects in complex scenes by using echolocation based on ‘tongue clicks’. A waveform analysis of the tongue clicks collected from three blind individuals is presented who use tongue-click based echolocation on a daily basis. It is found that the tongue clicks are wideband signals and that that the spectrum of clicks varies within and between individuals. However, by using the wideband ambiguity function, it is found that all of the clicks from three different individuals share some common characteristics.

Poster 2: Posterior lingual frenulum and breastfeeding

Introduction: The literature refers to ankyloglossia as anterior, when the lingual frenulum is visible, and posterior, when the frenulum is not visible. Posterior ankyloglossia is sometimes referred to as a submucosal tongue-tie. The anatomical variations of the posterior ankyloglossia and its interference with tongue movements are poorly described in the literature. Aim: The aim of this study is to verify the occurrence of posterior lingual frenulum in infants and its interference with sucking and swallowing during breastfeeding. Methods: This clinical study included 1084 newborns, who were assessed at 30 days of life, using the Lingual Frenulum Protocol for Infants (LFPI). This study included healthy full-term infants, who were being exclusively breastfed. Prematurity, perinatal complications, craniofacial anomalies, neurological disorders, and visible genetics syndromes were the exclusion criteria. The LFPI was administered to the infants, and the assessments were registered and videotaped. Tongue movements, sucking rhythm, sucking/swallowing/ breathing coordination, nipple chewing, and/or tongue clicking were assessed during nutritive and non-nutritive sucking evaluations. Descriptive statistics were performed. Results: Of the 1084 newborns, 479 (44.2%) had normal lingual frenulum; 380 (35%) had posterior lingual frenulum; and 225 (20.8%) had lingual frenulum alterations. Infants with posterior lingual frenulum did not have any restrictive tongue movement during sucking and swallowing. Conclusion: The occurrence of posterior frenulum in this sample was 35%. The posterior frenulum did not interfere with sucking and swallowing during breastfeeding; therefore, surgery was not recommended for any of the subjects in this sample.

Using awareness training to decrease nervous habits during public speaking

This study evaluated the effectiveness of awareness training for the reduction of three nervous habits that manifest during public speaking: filled pauses, tongue clicks, and inappropriate use of the word "like." Four university students delivered short speeches during baseline and assessment sessions. Awareness training resulted in meaningful reductions in target behaviors for all participants. Booster awareness training sessions were necessary for all participants to achieve further reductions in target behaviors. Generality probes conducted in front of a small audience indicated that treatment effects generally maintained. Social validity scores indicated that the treatment was acceptable, and participants indicated not only decreased use of verbal fillers, but also improved overall public speaking ability posttreatment.

Imitation: Not in Our Genes

A powerful longitudinal study has failed to find any evidence that newborn babies can imitate facial gestures, hand movements or vocalisations. After 40 years of uncertainty, these findings indicate that humans learn to imitate; this capacity is not inborn.