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Hearing aids help overcome the challenges associated with hearing loss, and thus greatly benefit and improve the lives of those living with hearing-impairment. Unfortunately, there is a lack of adoption of hearing aids among those that can benefit from hearing aids. Hearing researchers and audiologists are trying to address this problem through their research. However, the current proprietary hearing aid market makes it difficult for academic researchers to translate their findings into commercial use. In order to abridge this gap and accelerate research in hearing health care, we present the design and implementation of the Open Speech Platform (OSP), which consists of a co-design of open-source hardware and software. The hardware meets the industry standards and enables researchers to conduct experiments in the field. The software is designed with a systematic and modular approach to standardize algorithm implementation and simplify user interface development. We evaluate the performance of OSP regarding both its hardware and software, as well as demonstrate its usefulness via a self-fitting study involving human participants.

Purpose: The goal was to assess the effects of maturation and phonological development on performance, by normally hearing children, on an imitative test of auditory capacity (On-Line Imitative Test of Speech-Pattern Contrast Perception [OlimSpac]; Boothroyd, Eisenberg, & Martinez, 2006; Eisenberg, Martinez, & Boothroyd, 2003, 2007). Method: Thirty-four hearing children (aged between 1;8 [years;months] and 6;7) were asked to imitate nonword utterances. Responses were evaluated by a blinded listener in an 8-alternative forced-choice task, giving information on the children's ability to convey, by imitation, information about 6 binary phonemic contrasts. Results: Four children declined participation. Among 30 children aged 2;7 or older, performance improved significantly with age and varied with contrast. All children 3 years of age or older attained passing scores (7 or 8 correct responses in 8 binary trials) on at least 5 of the 6 contrasts. Post-alveolar consonant place was the contrast most often failed. Conclusions: When evaluated on a pass/fail basis, normally hearing children 3 years of age or older are likely to demonstrate auditory perception of most phonemic contrasts using this imitative test. Phonological development and other task-related factors have only a modest effect on performance by normally hearing children after 3 years of age. The effects of hearing loss, hearing age, sensory assistance, and listening experience in children with hearing loss remain to be determined.

Sixteen children with moderate to profound sensorineural hearing loss were trained on the production and auditory perception of sibilants over two 2-week periods. Perception performance improved significantly during training periods with a small amount of carryover to non-training contrast periods. Improvements in production performance occurred mostly after training, with more carryover to non-training contrasts. (Contains references.) (Author/DB)

This study examined whether a divided-attention, sentence recall task was more sensitive to distortion of the speech signal than a conventional focused-attention task with 18 normal hearing listeners. The study concluded that the simultaneous-sentence test, in its present form, is not more sensitive to the effects of peak clipping than is a single-sentence test in noise. (Contains references.) (Author/DB)

A study used the Three-Interval Forced-Choice Test of Speech Pattern Contrast Perception (THRIFT) to examine sensory-level speech-perception performance under the input modalities of hearing alone, speech-reading alone, and the two combined in 44 children (ages 5-10). Within each condition there were significant influences of age on performance for children below age seven. (Author/CR)

An imitative test of speech pattern contrast perception was administered to profoundly deaf children using hearing aids (n=76) or cochlear implants (n=18). Implant users performed, on average, similarly to individuals with an 88 decibel hearing loss, indicating that implant use can provide auditory speech perception capacity similar to that of severely deaf children who wear hearing aids. (Author/DB)

This article explores the influence of technological advances on the management of deafness, and discusses some reasons for delays between development of new technologies and their application to the needs of special populations. Surgical treatment, prosthetic treatment (including implants and microphones), speech training, computer-assisted instruction, and telecommunications are considered. (PB)

The benefits of two tactile codes of voice fundamental frequency ([F.sub.0]) were evaluated as supplements to the speechreading of sentences in two short-term training studies, each using 12 adults with normal hearing. In Experiment 1, a multichannel spatiotemporal display of [F.sub.0], known as Portapitch, was used to stimulate the index finger. In an attempt to improve on past performance with this display, the coding scheme was modified to better cover the [F.sub.0] range of the talker in the training materials. For Experiment 2, to engage kinesthetic/proprioceptive pathways, a novel single-channel positional display was built, in which [F.sub.0] was coded as the vertical displacement of a small finger-rest. Input to both displays consisted of synthesized replicas of the [F.sub.0] contours of the sentences, prepared and perfected off-line. Training with the two tactile [F.sub.0] displays included auditory presentation of the synthesized [F.sub.0] contours in conjunction with the tactile patterns on alternate trials. Speechreading enhancement by the two tactile [F.sub.0] displays was compared to the enhancement provided when auditory [F.sub.0] information was available in conjunction with the tactile patterns, by auditory presentation of a sinusoidal indication of the presence or absence of voicing, and by a single-channel tactile display of the speech waveform presented to the index finger. Despite the modified coding strategy, the multichannel Portapitch provided a mean tactile speechreading enhancement of 7 percentage points, which was no greater than that found in previous studies. The novel positional [F.sub.0] display provided only a 4 percentage point enhancement. Neither [F.sub.0] display was better than the simple single-channel tactile transform of the full speech waveform, which gave a 7 percentage point enhancement effect. Auditory speechreading enhancement effects were 17 percentage points with the voicing indicator and approximately 35 percentage points when the auditory [F.sub.0] contour was provided in conjunction with the tactile displays. The findings are consistent with the hypothesis that subjects were not taking full advantage of the [F.sub.0] variation information available in the outputs of the two experimental tactile displays. KEY WORDS: speechreading, lipreading, tactile aids, speech perception, fundamental frequency

Recognition of words in sentences of known topic was measured in normally hearing adults via speechreading alone and speechreading supplemented with auditory presentation of signals intended to convey variations of voice fundamental frequency (F(sub o)) over time. Three signals were used: (a) the low-pass filtered output of an electroglottograph (unprocessed F(sub o)), (b) a constant amplitude sine wave whose instantaneous frequency was intended to equal that of F(sub o) (processed F(sub o)), and (c) the same sine wave restricted to a small number of discrete frequency steps (quantized F(sub o)). As the number of steps in the quantized F(sub o) contours increased from 1 to 12, the speechreading enhancement effect increased. The quantized F(sub o) contour with 12 steps was as effective as the processed F(sub o) contour (without quantization), but this processed contour was significantly less effective than the unprocessed electroglottograph signal. The results show that the auditory F(sub o) speechreading enhancement effect is sensitive to the errors introduced by the F(sub o) extraction and regeneration process used in this study. It is also sensitive to the quantization of F(sub o) contours into less than 12 steps. Whether more than 12 steps are required for the full enhancement effect remains to be determined.

The speech production performance of 16 hearing-impaired subjects (13-19 years old) was measured using both experienced and inexperienced listeners. Results demonstrate that forced-choice tests can provide speech production measures that are virtually independent of listener experience, can provide analytic detail about production of phonetic contrasts, and are reasonably predictive of speech intelligibility in more natural settings. (Author/CL)

Two approaches to auditory training for improved speech recognition using 20 adults with mild to moderate sensorineural hearing impairments were compared. No significant differences were found between group one which spent training time on activities involving sentence perception and perceptual strategy and group two which focused on consonant recognition. (Author/DB)

Hearing-impaired speechreaders use linguistic context to compensate for the poor visibility of some speech movements. Constraints on spoken language enhance speechreading performance and help compensate for the paucity of sensory data. The largest effects come from linguistic constraints imposed by sentence context--syntactic, semantic, and topical constraints. (JDD)

The hypothesis that tactile presentation of voice fundamental frequency is as effective as auditory presentation in aiding speechreading was proven through auditory stimulation experiments, psychophysical studies, phonetic-level tactile studies, and sentence-level studies. After training with the device, three postlingually deafened adults experienced a reduction of speechreading error of 25 percent-50 percent. (Author/JDD)