Linda J. Ferrier

CONVERSATIONAL SKILLS OF INDIVIDUALS WITH FRAGILE‐X SYNDROME: A COMPARISON WITH AUTISM AND DOWN SYNDROME

The conversational skills of 18 individuals with fragile‐X syndrome (FXS) were compared with those of two other matched groups with autism and Down syndrome. The FXS group used more eliciting forms in conversation than those with Down syndrome, and also used partial self‐repetition more often than the other two groups. The Down syndrome group had more speech dysfluencies than those with autism, but not more than those with FXS. The autistic group used more inappropriate phrases. Qualitative analysis of behavioral phenotype may reveal differences in communicative organization among subgroups whose retardation is based on different genotypes. In addition, analysis of verbal strategies during conversation suggests important differences between individuals with FXS and autism.

Interactive speech pronunciation apparatus and method

An interactive speech pronunciation system for teaching pronunciation and reducing the accent of a user includes a memory for storing a plurality of presequenced lessons, an input interface for allowing a user to select predetermined ones of the presequenced lessons, a processor for executing program steps corresponding to the lessons selected by the user, and a monitor for displaying visual indicators to the user of the system. The speech pronunciation system further includes an audio input device, for recording sounds spoken by the user, an audio output device for transducing signals fed thereto to pre-recorded sounds and a speech processor for providing stored signals to the audio output device.

Dysarthric speakers' intelligibility and speech characteristics in relation to computer speech recognition

This research examined the use of the DragonDictate speech recognition system as a writing aid by 10 speakers with spastic dysarthria due to cerebral palsy with the ultimate goal of establishing prescription guidelines. The objectives were to (1) determine how intelligibility relates to recognition success; (2) determine those characteristics of speech, fluency, and voice that affect the accuracy level of the voice recognizer; and (3) investigate individual profiles of recognition over a series of dictations among high- and low-intelligibility dysarthric speakers versus nondisabled controls. Correlations between intelligibility measures and recognition success measures were strong. The total number of voice features correlated moderately with the number of readings needed to reach 80% recognition levels and with variability in recognition. The frequency of pauses showed a strong positive association with the number of readings subjects needed to reach 80% recognition. The frequency of nonspeech sounds was...

visiBabble for reinforcement of early vocalization

The visiBabble system processes infant vocalizations in real-time. It responds to the infants syllable-like productions with brightly colored animations and records the acoustic-phonetic analysis. The system reinforces the production of syllabic utterances that are associated with later language and cognitive development. We report here on the development of the visiBabble prototype and field-testing of the system.

Automatic babble recognition for early detection of speech related disorders

We have developed a program, the Early Vocalization Analyzer (EVA), that analyses digitized recordings of infant vocalizations. The purpose of such a system is to automatically and reliably screen infants who may be at risk for later communication problems. EVA applies the landmark detection theory of Stevens et al., for the recognition of acoustic features in adult speech, to detect syllables in vocalizations produced by typically developing six to thirteen month old infants. We discuss the differences between adult-specific code and code written to analyse infant vocalizations. In a validity test, EVA achieved 90% agreement in marking 128 landmarks commonly identified by two human judges, was often closer to one or both judges than the humans were to each other. In a second test EVA and a human judge had 86% agreement in identifying 150 landmarks.

Baby-Babble-Blanket: infant interface with automatic data collection

The Baby-Babble-Blanket (BBB), a pad with pressure-sensitive switches linked to a Macintosh computer, was developed to provide infants or developmentally delayed children with a communication/environmental control system. Lying on the pad, infants use early movements, such as head rolling or leg raising, to produce digitized sound. The BBB software automatically collects data on the overall number of switch activations and on particular switches in a variety of conditions and graphs them. Possible important uses of the BBB are to train cause-effect skills, to increase the overall amount of movement, or to encourage particular movements. Preliminary data were collected on a 5-month-old infant with club feet, hydrocephaly, and poor muscle tone to determine what movements the infant could use to access the pad, and whether the use of particular body parts could be increased by the ability to access the digitized mothers voice. Results suggest that the infant could activate the device by two different moveme...

Using the Baby-Babble-Blanket for infants with motor problems: an empirical study

Children with motor problems often develop to be passive, presumably because of an inability to communicate and to control the environment. The Baby-Babble-Blanket (BBB), a pad with pressure switches linked to a Macintosh computer, was developed to meet this need. Lying on the pad, infants use head-rolling, leg-lifting and kicking to produce digitized sound. Data is collected by the BBB software on the infants switch activations. An empirical study was carried out on a five-month-old infant with club feet, hydrocephaly and poor muscle tone to determine what movements the infant could use to access the pad, whether movements would increase over a baseline in response to sound, and what level of cause and effect the infant would demonstrate. Videotapes and switch activation data suggest that the infant: 1) could activate the device by rolling his head and raising his legs. 2) increased switch activations, over a no-sound baseline, in response to the sound of his mothers voice. 3) was able to change from using his head to raising his legs in response to the reinforcer.

EVA, an early vocalization analyzer: an empirical validity study of computer categorization

Previous research indicates that infant vocalizations are effective predictors of later articulation and language abilities (Locke, 1989, Menyuk, Liebergott, Shultz, Chesnick & Ferrier, 1991, Oller & Seibert 1988, Jensen, Boggild-Andersen, Schmidt, Ankerhus, Hansen, 1988). Intervention to encourage babbling activity in at-risk infants is frequently undertaken. Research and clinical diagnosis of delayed or reduced babbling have so far relied on time-consuming and unreliable perceptual analyses of recorded infant sounds. While acoustic analysis of infant sounds has provided important information on the early characteristics of infant vocalizations (Bauer, 1988, Stark 1986) this information has still to be used to carry out automatic, real-time analysis. We are developing a program, EVA, for the Macintosh computer that automatically analyzes digitized recordings of infant vocalizations. We describe the prototype and report on validity- testing of the first stage of development. Our human judge and EVA had 92.8% agreement on the number of utterances in the 20 minutes of recordings, commonly identifying 411 utterances. Their categorizations agreed 79.8% for duration and 87.3% for frequency, better than human inter-judge agreement reported in the literature. The authors hope that the final version of EVA will serve as a reliable standard for the analysis and evaluation of utterances of normal and at-risk infants with a variety of etiologies. The acoustic information gained from such analysis will allow us to develop a computer-based system to encourage early vocalization.

Clinical study of a dysarthric adult using a touch talker with words strategy

To maintain the credibility of professionals prescribing often expensive communication aids with synthetic speech output, it is becoming increasingly important to establish objective procedures for evaluating the relative gains in intelligibility and efficiency from these systems over natural speech. It is also critical to evaluate the use of the communication aid at the end of training. This descriptive study evaluated the intelligibility of a severely dysarthric speakers natural speech versus a Touch Talker with (1) an internal Echo speech synthesizer and (2) an external DECtalk. The assessment was carried out using a contextualized and decontextualized procedure. Both showed poor intelligibility of the users natural speech and considerable gains in intelligibility from the use of the two synthetic speech systems. Access to the system using direct selection was slow.For 1 year and 9 months, training was provided in the use of (1) a Touch Talker with Words Strategy, (2) a word processing package with w...

A baby babble-blanket

We have developed a multiple-switch-activated device with speech output for use by infants with severe speech and physical impairments. It is hoped that using this device for early intervention will provide these infants with a means of environmental control and communication with parents.