Logopenic and nonfluent variants of primary progressive aphasia are differentiated by acoustic measures of speech production

Differentiation of logopenic (lvPPA) and nonfluent/agrammatic (nfvPPA) variants of Primary Progressive Aphasia is important yet remains challenging since it hinges on expert based evaluation of speech and language production. In this study acoustic measures of speech in conjunction with voxel-based morphometry were used to determine the success of the measures as an adjunct to diagnosis and to explore the neural basis of apraxia of speech in nfvPPA. Forty-one patients (21 lvPPA, 20 nfvPPA) were recruited from a consecutive sample with suspected frontotemporal dementia. Patients were diagnosed using the current gold-standard of expert perceptual judgment, based on presence/absence of particular speech features during speaking tasks. Seventeen healthy age-matched adults served as controls. MRI scans were available for 11 control and 37 PPA cases; 23 of the PPA cases underwent amyloid ligand PET imaging. Measures, corresponding to perceptual features of apraxia of speech, were periods of silence during reading and relative vowel duration and intensity in polysyllable word repetition. Discriminant function analyses revealed that a measure of relative vowel duration differentiated nfvPPA cases from both control and lvPPA cases (r2 = 0.47) with 88% agreement with expert judgment of presence of apraxia of speech in nfvPPA cases. VBM analysis showed that relative vowel duration covaried with grey matter intensity in areas critical for speech motor planning and programming: precentral gyrus, supplementary motor area and inferior frontal gyrus bilaterally, only affected in the nfvPPA group. This bilateral involvement of frontal speech networks in nfvPPA potentially affects access to compensatory mechanisms involving right hemisphere homologues. Measures of silences during reading also discriminated the PPA and control groups, but did not increase predictive accuracy. Findings suggest that a measure of relative vowel duration from of a polysyllable word repetition task may be sufficient for detecting most cases of apraxia of speech and distinguishing between nfvPPA and lvPPA

A cross-lingual adaptation approach for rapid development of speech recognizers for learning disabled users

Building a voice-operated system for learning disabled users is a difficult task that requires a considerable amount of time and effort. Due to the wide spectrum of disabilities and their different related phonopathies, most approaches available are targeted to a specific pathology. This may improve their accuracy for some users, but makes them unsuitable for others. In this paper, we present a cross-lingual approach to adapt a general-purpose modular speech recognizer for learning disabled people. The main advantage of this approach is that it allows rapid and cost-effective development by taking the already built speech recognition engine and its modules, and utilizing existing resources for standard speech in different languages for the recognition of the users’ atypical voices. Although the recognizers built with the proposed technique obtain lower accuracy rates than those trained for specific pathologies, they can be used by a wide population and developed more rapidly, which makes it possible to design various types of speech-based applications accessible to learning disabled users.This research was supported by the project ‘Favoreciendo la vida autónoma de discapacitados intelectuales con problemas de comunicación oral mediante interfaces personalizados de reconocimiento automático del habla’, financed by the Centre of Initiatives for Development Cooperation (Centro de Iniciativas de Cooperación al Desarrollo, CICODE), University of Granada, Spain. This research was supported by the Student Grant Scheme 2014 (SGS) at the Technical University of Liberec

King Abdullah University of Science and Technology (KAUST) mooring deployment cruise and fieldwork report, fall 2008 R/V Oceanus voyage 449-5, October 9, 2008–October 14, 2008

King Abdullah University of Science and Technology (KAUST) is being built near Thuwal, Saudi Arabia with the goal of becoming a world-class, graduate-level research university. As a step toward this goal, KAUST has partnered with the Woods Hole Oceanographic Institution (WHOI) to undertake various studies of the oceanography of the Red Sea in order to establish a research program in ocean sciences by the time the university opens its doors in the fall of 2009. Two of the KAUST-WHOI research projects involve deployment of surface moorings and associated instrumentation to measure physical properties of the Red Sea, such as temperature, salinity, and currents, at four locations off the coast of Saudi Arabia. The goal of these measurements is to better understand the evolution and dynamics of the circulation and air-sea interaction in the Red Sea. Two surface moorings and two bottom tripods (PI, Steven Lentz) were deployed at 50-55-m depth near 21°57'N, 38°46'E over the continental shelf close to the Saudi coast. An additional surface mooring/bottom tripod pair was deployed near 21°58'N, 38°50'E at the outer fringe of a reef system directly onshore of the shelf mooring/tripod pairs (PI, Lentz). The coastal moorings carry instruments to estimate temperature, salinity, and fluorescence; and the nearby bottom tripods support instruments to measure bottom pressure and the vertical profile of the currents. Additional instruments, principally bottom temperature sensors, were deployed over the reef system onshore of the shelf moorings. One air-sea interaction mooring (PI, J. Thomas Farrar) was deployed at 693-m depth near 22°10'N, 38°30'E. The air-sea interaction mooring carries instruments for measuring temperature, salinity, (water) velocity, winds, air temperature, humidity, barometric pressure, incident sunlight, infrared radiation, precipitation, and surface waves. A coastal meteorological tower was also installed on the KAUST campus in Thuwal (PI, Farrar). These measurements are of value because there are few time series of oceanographic and meteorological properties of the Red Sea that can be used to characterize the circulation, test numerical models of the Red Sea circulation, or formulate theoretical models of the physics of the Red Sea circulation. These measurements will permit a characterization of the Red Sea circulation with high temporal resolution at the mooring locations, and accurate in-situ estimates of the air-sea exchange of heat, freshwater, and momentum. In October 2008, a cruise was made aboard the R/V Oceanus to deploy the shelf and air-sea interaction moorings, and other fieldwork (e.g., tower instrumentation and deployment of reef instrumentation) was conducted after the cruise. Some additional data were collected during the cruise with shipboard instrumentation. This report documents the cruise and the data collected during the fall 2008 fieldwork.Funding for this report was provided by the King Abdullah University of Science and Technology (KAUST) under a cooperative research agreement with Woods Hole Oceanographic Institution