Psychometric Functions of Vowel Detection and Identification in Long-Term Speech-Shaped Noise.

Purpose The goal of this study was to investigate vowel detection and identification in noise and provide baseline data regarding how vowel perception changed with signal-to-noise ratios. Psychometric functions of vowel detection and identification for 12 American English isolated vowels in long-term speech-shaped noise were examined for young listeners with normal hearing in this study. Method Vowel detection was measured at sensation levels from -10 to +5 dB (re: thresholds of vowel detection from the study of Liu and Eddins, 2008a ) with a 4-interval forced-choice procedure. Thresholds of vowel detection were computed for each listener as the speech level at which 70.7% correct performance was reached. Vowel identification was then examined at sensation levels from 0 to 12 dB relative to detection thresholds for each listener. Thresholds of vowel identification were calculated as the speech level with vowel identifiability ( d') equals to 1. Results Thresholds of vowel detection and identification were significantly affected by vowel category. Slopes of psychometric functions of vowel identification were significantly dependent on vowel category, whereas slopes of psychometric functions of vowel detection were not. Conclusions These results suggest that, given the same sensation levels, especially at low sensation levels, vowel sounds are not equally perceivable in terms of identifiability.

[Development of a Play Toolkit for Supporting Infant and Toddler Development in Kyrgyzstan with a Focus on the Symbolic Functioning and Fine Motor Development of Infants 6 to 36 Months Old]. / 키르기스스탄 ì˜ìœ ì•„ 성장발달을 위한 놀이도구 개발 및 사용효과 평가: 6~36개월 ì˜ìœ ì•„ì˜ ìƒì§•ì  기능 ì‚¬ê³ ì™€ 미세운동 발달 중심으로.

PURPOSE: The study aimed to develop a play toolkit to facilitate infants' and toddlers' symbolic thought and fine motor development. METHODS: This study used a methodological study design including two phases of development and evaluation. After reviewing the play culture and developmental health issues in Kyrgyzstan through a literature review and interviews with local experts and parents, the toolkit was developed and evaluated using content validity and utilization tests. RESULTS: The toolkit was based on Westby's symbolic play and the fine motor milestones in the Bright Futures Guidelines. The Toolkits were composed of an overall suggested play schedule according to the child's age, four kinds of play props, and a utilization guidebook for parents. The play props were a felt book, sorting and assembling blocks, cup blocks, and a tangram. The guidebook contained age-appropriate operating methods and alternative ways to use the materials. CONCLUSION: A play toolkit was developed to enhance nurturing practices among parents of infants and toddlers. The findings may help facilitate effective interactions between parents and their children. Considering that nurturing care is critical for achieving better child health outcomes, enhancing parenting resources and parent-child relations could function as an effective strategy for promoting child health.

English Consonant Identification in Multi-Talker Babble: Effects of Chinese-Native Listeners' English Experience.

The identification of English consonants in quiet and multi-talker babble was examined for three groups of young adult listeners: Chinese in China, Chinese in the USA (CNU), and English-native listeners. As expected, native listeners outperformed non-native listeners. The two non-native groups had similar performance in quiet, whereas CNU listeners performed significantly better than Chinese in China listeners in babble. It is concluded that CNU listeners may benefit from English experience, for example, better use of temporal variation in noise and better capacity against informational masking, to perceive English consonants better in babble. Possible explanations regarding the differential noise effect on the three groups are discussed.

Actin-binding LIM protein 1 regulates receptor activator of NF-κB ligand-mediated osteoclast differentiation and motility.

Actin-binding LIM protein 1 (ABLIM1), a member of the LIM-domain protein family, mediates interactions between actin filaments and cytoplasmic targets. However, the role of ABLIM1 in osteoclast and bone metabolism has not been reported. In the present study, we investigated the role of ABLIM1 in the receptor activator of NF-κB ligand (RANKL)- mediated osteoclastogenesis. ABLIM1 expression was induced by RANKL treatment and knockdown of ABLIM1 by retrovirus infection containing Ablim1-specific short hairpin RNA (shAblim1) decreased mature osteoclast formation and bone resorption activity in a RANKL-dose dependent manner. Coincident with the downregulated expression of osteoclast differentiation marker genes, the expression levels of c-Fos and the nuclear factor of activated T-cells cytoplasmic 1 (NFATc1), critical transcription factors of osteoclastogenesis, were also decreased in shAblim1-infected osteoclasts during RANKLmediated osteoclast differentiation. In addition, the motility of preosteoclast was reduced by ABLIM1 knockdown via modulation of the phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K)/Akt/Rac1 signaling pathway, suggesting another regulatory mechanism of ABLIM1 in osteoclast formation. These data demonstrated that ABLIM1 is a positive regulator of RANKLmediated osteoclast formation via the modulation of the differentiation and PI3K/Akt/Rac1-dependent motility. [BMB Reports 2018; 51(7): 356-361].

Pueraria lobate Inhibits RANKL-Mediated Osteoclastogenesis Via Downregulation of CREB/PGC1ß/c-Fos/NFATc1 Signaling.

Puerariae radix, the dried root of Pueraria lobate Ohwi, is known to prevent bone loss in ovariectomized mice; however, the precise molecular mechanisms are not understood. In this study, we investigated the effects and underlying mechanisms of action of Puerariae radix extract (PRE) on receptor activator of NF-κB ligand (RANKL)-induced osteoclastogenesis. PRE dose-dependently inhibited osteoclast differentiation and formation, decreased the bone-resorbing activity of osteoclasts, and downregulated the expression of osteoclast differentiation marker genes. The expression of osteoclastogenic factors produced by PRE-treated osteoblasts such as RANKL, macrophage colony-stimulating factor (M-CSF), and osteoprotegerin (OPG) was comparable to that of untreated (control) cells. However, the formation of osteoclasts via bone marrow cell and calvaria-derived osteoblast co-cultures was suppressed by PRE treatment. Therefore, the inhibitory effects of PRE on osteoclastogenesis clearly targeted osteoclasts, but not osteoblasts. PRE treatment considerably reduced RANKL-induced mitogen-activated protein kinases (MAPKs) activity, especially c-Jun N-terminal kinase, in osteoclast precursor cells. In addition, PRE markedly suppressed cAMP response element-binding protein (CREB) activation and the induction of peroxisome proliferator-activated receptor gamma coactivator 1ß (PGC1ß), which stimulate osteoclastogenesis - an effect that was not observed for puerarin and 17-ß estradiol. Finally, PRE treatment significantly repressed the expression of c-Fos and the nuclear factor of activated T-cells cytoplasmic 1 (NFATc1), which is a master transcription factor for osteoclastogenesis in vitro and in vivo. Overall, these results strongly suggest that PRE is an effective inhibitor of RANKL-induced osteoclastogenesis and may be a potent therapeutic agent for bone-related diseases such as osteoporosis, rheumatoid arthritis, and periodontitis.

Cytosolic malate dehydrogenase regulates RANKL-mediated osteoclastogenesis via AMPK/c-Fos/NFATc1 signaling.

Cytosolic malate dehydrogenase (malate dehydrogenase 1, MDH1) plays pivotal roles in the malate/aspartate shuttle that might modulate metabolism between the cytosol and mitochondria. In this study, we investigated the role of MDH1 in osteoclast differentiation and formation. MDH1 expression was induced by receptor activator of nuclear factor kappa-B ligand (RANKL) treatment. Knockdown of MDH1 by infection with retrovirus containing MDH1-specific shRNA (shMDH1) reduced mature osteoclast formation and bone resorption activity. Moreover, the expression of marker genes associated with osteoclast differentiation was downregulated by shMDH1 treatment, suggesting a role of MDH1 in osteoclast differentiation. In addition, intracellular ATP production was reduced following the activation of adenosine 5' monophosphate-activated protein kinase (AMPK), a cellular energy sensor and negative regulator of RANKL-induced osteoclast differentiation, in shMDH1-infected osteoclasts compared to control cells. In addition, the expression of c-Fos and nuclear factor of activated T-cells, cytoplasmic 1 (NFATc1), a critical transcription factor of osteoclastogenesis, was decreased with MDH1 knockdown during RANKL-mediated osteoclast differentiation. These findings provide strong evidence that MDH1 plays a critical role in osteoclast differentiation and function via modulation of the intracellular energy status, which might affect AMPK activity and NFATc1 expression.

Auditory detection of non-speech and speech stimuli in noise: Effects of listeners' native language background.

This study investigated whether native listeners processed speech differently from non-native listeners in a speech detection task. Detection thresholds of Mandarin Chinese and Korean vowels and non-speech sounds in noise, frequency selectivity, and the nativeness of Mandarin Chinese and Korean vowels were measured for Mandarin Chinese- and Korean-native listeners. The two groups of listeners exhibited similar non-speech sound detection and frequency selectivity; however, the Korean listeners had better detection thresholds of Korean vowels than Chinese listeners, while the Chinese listeners performed no better at Chinese vowel detection than the Korean listeners. Moreover, thresholds predicted from an auditory model highly correlated with behavioral thresholds of the two groups of listeners, suggesting that detection of speech sounds not only depended on listeners' frequency selectivity, but also might be affected by their native language experience. Listeners evaluated their native vowels with higher nativeness scores than non-native listeners. Native listeners may have advantages over non-native listeners when processing speech sounds in noise, even without the required phonetic processing; however, such native speech advantages might be offset by Chinese listeners' lower sensitivity to vowel sounds, a characteristic possibly resulting from their sparse vowel system and their greater cognitive and attentional demands for vowel processing.

English vowel identification in quiet and noise: effects of listeners' native language background.

PURPOSE: To investigate the effect of listener's native language (L1) and the types of noise on English vowel identification in noise. METHOD: Identification of 12 English vowels was measured in quiet and in long-term speech-shaped noise and multi-talker babble (MTB) noise for English- (EN), Chinese- (CN) and Korean-native (KN) listeners at various signal-to-noise ratios (SNRs). RESULTS: Compared to non-native listeners, EN listeners performed significantly better in quiet and in noise. Vowel identification in long-term speech-shaped noise and in MTB noise was similar between CN and KN listeners. This is different from our previous study in which KN listeners performed better than CN listeners in English sentence recognition in MTB noise. DISCUSSION: RESULTS from the current study suggest that depending on speech materials, the effect of non-native listeners' L1 on speech perception in noise may be different. That is, in the perception of speech materials with little linguistic cues like isolated vowels, the characteristics of non-native listener's native language may not play a significant role. On the other hand, in the perception of running speech in which listeners need to use more linguistic cues (e.g., acoustic-phonetic, semantic, and prosodic cues), the non-native listener's native language background might result in a different masking effect.

The effects of aging on speech perception in noise: comparison between normal-hearing and cochlear-implant listeners.

BACKGROUND: Speech understanding in noise is comparatively more problematic for older listeners with and without hearing loss, and age-related changes in temporal resolution might be associated with reduced speech recognition in complex noise. PURPOSE: The purpose of this study was to investigate the effects of aging on temporal processing and speech perception in noise for normal-hearing (NH) and cochlear-implant (CI) listeners. RESEARCH DESIGN: All participants completed three experimental procedures: (1) amplitude modulation (AM) detection thresholds, (2) sentence recognition in quiet, and (3) speech recognition in steady or modulating noise. STUDY SAMPLE: Four listener groups participated in the study: 11 younger (≤ 30 yr old, YNH) listeners and 12 older (> 60 yr old, ONH) listeners with NH and 7 younger (< 55 yr old, YCI) and 6 older (> 60 yr old, OCI) CI users. CI listeners have been wearing their device either monaurally or binaurally at least 1 yr. DATA COLLECTION AND ANALYSIS: For speech recognition testing, there were eight listening conditions in noise (4 modulation frequencies × 2 signal-to-noise ratios) and one in quiet for each listener. For modulation detection testing, a broadband noise with a duration of 500 msec served as the stimuli at three temporal modulation frequencies of 2, 4, and 8 Hz, which were used to modulate the noise in the speech recognition experiment. We measured AM detection thresholds using a two-interval, two-alternative, forced-choice adaptive procedure. We conducted a series of analysis of variance tests to examine the effect of aging on each test result and measured the correlation coefficient between speech recognition in noise and modulation detection thresholds. RESULTS: Although older NH and CI listeners performed similar to the younger listeners with the same hearing status for sentence recognition in quiet, there was a significant aging effect on speech recognition in noise. Regardless of modulation frequency and signal-to-noise ratio, speech recognition scores of the older listeners were poorer than those of the younger listeners when hearing status was matched. We also found a significant effect of aging on AM detection at each modulating frequency and a strong correlation between speech recognition in modulating noise and AM detection thresholds at 2 and 4 Hz. CONCLUSIONS: Regardless of differences in hearing status, the degree and pattern of aging effect on auditory processing of the NH listener groups were similar to those of the CI listener groups. This result suggests that age-related declines in speech understanding are likely multifactorial, including peripheral and central factors. Although the age cutoff of the current older age group was 10 yr less than in previous studies (Dubno et al, 2002; Lin et al, 2011), we still found the age-related differences on two auditory tasks. This study extends the knowledge of age-related auditory perception difficulties to CI listeners.

Durations of American English vowels by native and non-native speakers: acoustic analyses and perceptual effects.

The goal of this study was to examine durations of American English vowels produced by English-, Chinese-, and Korean-native speakers and the effects of vowel duration on vowel intelligibility. Twelve American English vowels were recorded in the /hVd/ phonetic context by native speakers and non-native speakers. The English vowel duration patterns as a function of vowel produced by non-native speakers were generally similar to those produced by native speakers. These results imply that using duration differences across vowels may be an important strategy for non-native speakers' production before they are able to employ spectral cues to produce and perceive English speech sounds. In the intelligibility experiment, vowels were selected from 10 native and non-native speakers and vowel durations were equalized at 170 ms. Intelligibility of vowels with original and equalized durations was evaluated by American English native listeners. Results suggested that vowel intelligibility of native and non-native speakers degraded slightly by 3-8% when durations were equalized, indicating that vowel duration plays a minor role in vowel intelligibility.

Intelligibility of American English vowels and consonants spoken by international students in the United States.

PURPOSE The purpose of this study was to examine the intelligibility of English consonants and vowels produced by Chinese-native (CN), and Korean-native (KN) students enrolled in American universities. METHOD 16 English-native (EN), 32 CN, and 32 KN speakers participated in this study. The intelligibility of 16 American English consonants and 16 vowels spoken by native and nonnative speakers of English was evaluated by EN listeners. All nonnative speakers also completed a survey of their language backgrounds. RESULTS Although the intelligibility of consonants and diphthongs for nonnative speakers was comparable to that of native speakers, the intelligibility of monophthongs was significantly lower for CN and KN speakers than for EN speakers. Sociolinguistic factors such as the age of arrival in the United States and daily use of English, as well as a linguistic factor, difference in vowel space between native (L1) and nonnative (L2) language, partially contributed to vowel intelligibility for CN and KN groups. There was no significant correlation between the length of U.S. residency and phoneme intelligibility. CONCLUSION Results indicated that the major difficulty in phonemic production in English for Chinese and Korean speakers is with vowels rather than consonants. This might be useful for developing training methods to improve English intelligibility for foreign students in the United States.

Hearing conservation program for marching band members: a risk for noise-induced hearing loss?

PURPOSE: To examine the risk for noise-induced hearing loss (NIHL) in university marching band members and to provide an overview of a hearing conservation program for a marching band. METHOD: Sound levels during band rehearsals were recorded and audiometric hearing thresholds and transient otoacoustic emission were measured over a 3-year period. Musician's earplugs and information about hearing loss were provided to the students. The hearing thresholds of other college students were tested as a partial control. RESULTS: There were no significant differences in hearing thresholds between the two groups. During initial testing, more marching band members showed apparent high-frequency notches than control students. Follow-up hearing tests in a subsequent year for the marching band members showed that almost all notches disappeared. Persistent standard threshold shift (STS) across tests was not observed in the band members. CONCLUSION: Band members showed no evidence of STS or persistent notched audiograms. Because accepted procedures for measuring hearing showed a lack of precision in reliably detecting early NIHL in marching band members, it is recommended that signs of NIHL be sought in repeated measurements compared to baseline audiograms rather than in a single measure (a single notch). A hearing conservation program for this population is still recommended because of lengthy rehearsal times with high sound-level exposure during rehearsals.

Masking release and modulation interference in cochlear implant and simulation listeners.

PURPOSE: To examine the effects of temporal and spectral interference of masking noise on sentence recognition for listeners with cochlear implants (CI) and normal-hearing persons listening to vocoded signals that simulate signals processed through a CI (NH-Sim). METHOD: NH-Sim and CI listeners participated in the experiments using speech and noise that were processed by bandpass filters. Depending on the experimental condition, the spectra of the maskers relative to that of speech were set to be completely embedded with, partially overlapping, or completely separate from, the speech. The maskers were either steady or amplitude modulated and were presented at +10 dB signal-to-noise ratio. RESULTS: NH-Sim listeners experienced progressively more masking as the masker became more spectrally overlapping with speech, whereas CI listeners experienced masking even when the masker was spectrally remote from the speech signal. Both the NH-Sim and CI listeners experienced significant modulation interference when noise was modulated at a syllabic rate (4 Hz), suggesting that listeners may experience both modulation interference and masking release. Thus, modulated noise has mixed and counteracting effects on speech perception. CONCLUSION: When the NH-Sim and CI listeners with poor spectral resolution were tested using syllabic-like rates of modulated noise, they tended to integrate or confuse the noise with the speech, causing an increase in speech errors. Optional training programs might be useful for CI listeners who show more difficulty understanding speech in noise.

The vowel inherent spectral change of English vowels spoken by native and non-native speakers.

The current study examined Vowel Inherent Spectral Change (VISC) of English vowels spoken by English-, Chinese-, and Korean-native speakers. Two metrics, spectral distance (amount of spectral shift) and spectral angle (direction of spectral shift) of formant movement from the onset to the offset, were measured for 12 English monophthongs produced in a /hvd/ context. While Chinese speakers showed significantly greater spectral distances of vowels than English and Korean speakers, there was no significant speakers' native language effect on spectral angles. Comparisons to their native vowels for Chinese and Korean speakers suggest that VISC might be affected by language-specific phonological structure.

English vowel identification in long-term speech-shaped noise and multi-talker babble for English and Chinese listeners.

The identification of 12 English vowels was measured in quiet and in long-term speech-shaped noise (LTSSN) and multi-talker babble for English-native (EN) listeners and Chinese-native listeners in the U.S. (CNU) and China (CNC). The signal-to-noise ratio was manipulated from -15 to 0 dB. As expected, EN listeners performed significantly better in quiet and noisy conditions than CNU and CNC listeners. Vowel identification in LTSSN was similar between CNU and CNC listeners; however, performance in babble was significantly better for CNU listeners than for CNC listeners, indicating that exposing non-native listeners to native English may reduce informational masking of multi-talker babble.

English sentence recognition in speech-shaped noise and multi-talker babble for English-, Chinese-, and Korean-native listeners.

This study aimed to investigate English sentence recognition in quiet and two types of maskers, multi-talker babble (MTB) and long-term speech-shaped noise (LTSSN), with varied signal-to-noise ratios, for English-, Chinese-, and Korean-native listeners. Results showed that first, sentence recognition for non-native listeners was affected more by background noise than that for native listeners; second, the masking effects of LTSSN were similar between Chinese and Korean listeners, but the masking effects of MTB were greater for Chinese than for Korean listeners, suggesting possible interaction effects between the non-native listener's native language and speech-like competing noise in sentence recognition.

Audibility of American English vowels produced by English-, Chinese-, and Korean-native speakers in long-term speech-shaped noise.

The purpose of this study was to evaluate whether there were significant differences in audibility of American English vowels in noise produced by non-native and native speakers. Detection thresholds for 12 English vowels with equalized durations of 170 ms produced by 10 English-, Chinese- and Korean-native speakers were measured for young normal-hearing English-native listeners in the presence of speech-shaped noise presented at 70 dB SPL. Similar patterns of vowel detection thresholds as a function of the vowel category were found for native and non-native speakers, with the highest thresholds for /u/ and /ʊ/ and lowest thresholds for /i/ and /e/. In addition, vowel detection thresholds for non-native speakers were significantly lower and showed greater speaker variability than those for native speakers. Thresholds for vowel detection predicted from an excitation-pattern model corresponded well to behavioral thresholds, implying that vowel detection was primarily determined by the vowel spectrum regardless of speaker language background. Both behavioral and predicted thresholds showed that vowel audibility was similar or even better for non-native speakers than for native speakers, indicating that vowel audibility did not account for non-native speakers' lower-than-native intelligibility in noise. Effects of non-native speakers' English proficiency level on vowel audibility are discussed.

Interrupted speech perception: the effects of hearing sensitivity and frequency resolution.

Jin & Nelson (2006) found that although amplified speech recognition performance of hearing-impaired (HI) listeners was equal to that of normal-hearing (NH) listeners in quiet and in steady noise, nevertheless HI listeners' performance was significantly poorer in modulated noise. As a follow-up, the current study investigated whether three factors, auditory integration, low-mid frequency audibility and auditory filter bandwidths, might contribute to reduced sentence recognition of HI listeners in the presence of modulated interference. Three findings emerged. First, sentence recognition in modulated noise found in Jin & Nelson (2006) was highly correlated with perception of sentences interrupted by silent gaps. This suggests that understanding speech interrupted by either noise or silent gaps require similar perceptual integration of speech fragments available either in the dips of a gated noise or across silent gaps of an interrupted speech signal. Second, those listeners with greatest hearing losses in the low frequencies were poorest at understanding interrupted sentences. Third, low-to mid-frequency hearing thresholds accounted for most of the variability in Masking Release (MR) for HI listeners. As suggested by Oxenham and his colleagues (2003 and 2009), low-frequency information within speech plays an important role in the perceptual segregation of speech from competing background noise.

Speech perception in gated noise: the effects of temporal resolution.

Previous investigations have suggested that hearing-impaired (HI) listeners have reduced masking release (MR) compared to normal hearing listeners (NH) when they listen in modulated noise. The current study examined the following questions that have not been clearly answered: First, when HI listeners are amplified so that their performance is equal to that of NH listeners in quiet and in steady noise, do HI listeners still show reduced MR with modulated noise when compared to NH listeners? Second, is the masking release the same for sentences and CV syllables? Third, does forward masking significantly contribute to the variability in performance among HI listeners? To compensate for reduced hearing sensitivity for HI listeners, the spectrum levels of both speech and noise were adjusted based on the individual hearing loss. There was no significant difference between the performance of NH listeners and that of HI listeners in steady noise and in quiet. However, the amount of MR for sentences and for CV syllables was significantly reduced for HI listeners. For sentence recognition, the amount of MR seemed to be more related to hearing sensitivity for low-to-mid frequencies than to forward masking. In contrast, forward masking thresholds appear to be a major contributor to the amount of MR for syllable recognition.

Factors affecting speech understanding in gated interference: cochlear implant users and normal-hearing listeners.

Previous work [Nelson, Jin, Carney, and Nelson (2003), J. Acoust. Soc. Am. 113, 961-968] suggested that cochlear implant users do not benefit from masking release when listening in modulated noise. The previous findings indicated that implant users experience little to no release from masking when identifying sentences in speech-shaped noise, regardless of the modulation frequency applied to the noise. The lack of masking release occurred for all implant subjects who were using three different devices and speech processing strategies. In the present study, possible causes of this reduced masking release in implant listeners were investigated. Normal-hearing listeners, implant users, and normal-hearing listeners presented with a four-band simulation of a cochlear implant were tested for their understanding of sentences in gated noise (1-32 Hz gate frequencies) when the duty cycle of the noise was varied from 25% to 75%. No systematic effect of noise duty cycle on implant and simulation listeners' performance was noted, indicating that the masking caused by gated noise is not only energetic masking. Masking release significantly increased when the number of spectral channels was increased from 4 to 12 for simulation listeners, suggesting that spectral resolution is important for masking release. Listeners were also tested for their understanding of gated sentences (sentences in quiet interrupted by periods of silence ranging from 1 to 32 Hz as a measure of auditory fusion, or the ability to integrate speech across temporal gaps. Implant and simulation listeners had significant difficulty understanding gated sentences at every gate frequency. When the number of spectral channels was increased for simulation listeners, their ability to understand gated sentences improved significantly. Findings suggest that implant listeners' difficulty understanding speech in modulated conditions is related to at least two (possibly related) factors: degraded spectral information and limitations in auditory fusion across temporal gaps.