Copyright 2009 LENA FoundationInfoture Technical Research Reportshttp://www.rssboard.org/rss-specificationLENA Foundation RSS Generator31http://www.lenafoundation.org/http://www.lenafoundation.org/Images/M_Logo.png88en-USThu, 11 Aug 2011 13:15:29 -0600http://www.lenafoundation.org/Fri, 10 Feb 2012 00:00:00 -060060info@lenafoundation.org (LenaBaby WebMaster)Overview of LENA development and surprising findings, both confirming and expanding on Hart and Risley’s ground breaking work.http://www.lenafoundation.org/TechReport.aspx/PowerOfTalk/LTR-01-1http://www.lenafoundation.org/TechReport.aspx/PowerOfTalk/LTR-01-1Mon, 01 Oct 2007 00:00:00 -0600Overview of LENA development and surprising findings, both confirming and expanding on Hart and Risley’s ground breaking work.http://www.lenafoundation.org/TechReport.aspx/PowerOfTalk/LTR-01-2http://www.lenafoundation.org/TechReport.aspx/PowerOfTalk/LTR-01-2Wed, 11 Feb 2009 14:22:56 -0600The current paper describes the LENA Natural Language Study, an ongoing data collection effort designed to provide information about the language environment of infants and toddlers. Data collected contributes to product development and normative information for use with the LENA™ System. Study participants were representative of the US Census with respect to mothers’ attained education, and consisted of 314 normally developing infants and toddlers from monolingual English-speaking households living in the Denver-metro area. Participants provided day-long audio files of their natural language environment once a month, and certified speech language pathologists assessed participant language ability independently through standardized assessments. The resulting normative database contains over 18,000 hours of spontaneous speech data. This paper describes how normative information was derived for the Adult Word Count estimates (adult words spoken per day) and Conversational Turns estimates (adult-child alternations per day) that are reported in the LENA System.http://www.lenafoundation.org/TechReport.aspx/Natural_Language_Study/LTR-02-1http://www.lenafoundation.org/TechReport.aspx/Natural_Language_Study/LTR-02-1Wed, 17 Oct 2007 00:00:00 -0600This paper describes the multiphase LENA Natural Language Study, an ongoing data collection effort designed to investigate the language environment of infants and toddlers. Data collected contributes to product development and normative information for use with the LENA System and child development research. Phase I study participants were representative of the U.S. Census with respect to mothers’ attained education and consisted of 329 normally developing infants and toddlers from monolingual English-speaking households living in the Denver-metro area. Participants provided daylong audio recordings of their natural language environment once a month, and certified speech language pathologists assessed participant language ability independently through standardized assessments. A subset of 80 phase I participants has continued to provide monthly recordings in phase II of the study. The normative database described herein contains over 32,000 hours of spontaneous speech data. This paper describes how normative information was derived for the Adult Word Count estimates (AWC; adult words spoken per day), Conversational Turns estimates (CT; adult-child alternations per day), and Child Vocalization frequency estimates (CV; words, babbles, and “protophones” or pre-speech communicative sounds) that are reported in the LENA System.http://www.lenafoundation.org/TechReport.aspx/Natural_Language_Study/LTR-02-2http://www.lenafoundation.org/TechReport.aspx/Natural_Language_Study/LTR-02-2Tue, 16 Sep 2008 00:00:00 -0600The LENA language environment analysis system was designed to estimate adult and key child interactions in natural home environments. Contrary to controlled clinical research environments, the speech used by the participants in this study was real, unrehearsed, and representative of each child’s typical daily language environment. In this paper, we describe the audio processing system in terms of information low, feature extraction, and segmentation identification. We also reveal the audio specifications that were either met or exceeded during the development and design of the LENA Digital Language Processor (DLP).http://www.lenafoundation.org/TechReport.aspx/Audio_Specifications/LTR-03-2http://www.lenafoundation.org/TechReport.aspx/Audio_Specifications/LTR-03-2Tue, 16 Sep 2008 00:00:00 -0600The LENA™ language environment analysis system was designed to estimate adult and key child interactions in natural home environments. Contrary to controlled linguistic research environments, the speech used by the participants in this study was real, unrehearsed, and representative of each child’s typical daily language environment. In this paper, we describe the Audio Processing System in terms of information flow, feature extraction, and segmentation identification. We also reveal the audio specifications that were either met or exceeded during the development and design of the LENA digital language processor (DLP).http://www.lenafoundation.org/TechReport.aspx/Audio_Specifications/LTR-03-1http://www.lenafoundation.org/TechReport.aspx/Audio_Specifications/LTR-03-1Wed, 17 Oct 2007 00:00:00 -0600The LENA™ Digital Language Processor records real-time audio data that is transferred to a computer for processing by LENA language environment software V2.3.0. An LENA Time Segment (ITS) file is created that summarizes information contained in the original audio file. To date, our focus has been estimating adult word counts and conversational turns between adult and key child. However, other audio factors are processed that have not yet been studied. Three versions of the LENA System exist: a consumer version; a clinician version; and a research version. The research version provides access to the ITS file. Here we describe the general content of the ITS file, detail the specific components, and discuss implications with regard to potential research goals. http://www.lenafoundation.org/TechReport.aspx/ITS_File/LTR-04-1http://www.lenafoundation.org/TechReport.aspx/ITS_File/LTR-04-1Wed, 17 Oct 2007 00:00:00 -0600The LENA Digital Language Processor (DLP) records real-time audio data that is transferred to a computer for processing by LENA language environment software V3.1.0. Ultimately an Interpreted Time Segments (ITS) file is created that summarizes the processing results for the data contained within the original audio file. LENA data analyses have focused primarily on estimating Adult Word Counts (AWC), Child Vocalizations (CV), and Conversational Turns (CT) between adult and key child. however, the data processing reveals numerous other factors that have not yet been studied by researchers at LENA Foundation. In this paper, we reveal the general content of the ITS file. We also provide a detailed description of each component specific to the ITS file and implications with regard to potential research and analyses.http://www.lenafoundation.org/TechReport.aspx/ITS_File/LTR-04-2http://www.lenafoundation.org/TechReport.aspx/ITS_File/LTR-04-2Tue, 16 Sep 2008 00:00:00 -0600The LENA language environment analysis system was designed to provide information about the language environment of infants and toddlers. In this technical report, we describe the reliability of the LENA System in terms of segmentation, adult word counts, and child vocalizations. We also describe unique sources of variability associated with data collection in the natural home environment.http://www.lenafoundation.org/TechReport.aspx/Reliability/LTR-05-2http://www.lenafoundation.org/TechReport.aspx/Reliability/LTR-05-2Thu, 05 Feb 2009 09:30:25 -0600The LENA™ language environment analysis system was designed to provide information about the language environment of infants and toddlers. In this technical report, we describe the reliability of the LENA System in terms of segmentation, adult word counts, and child vocalizations. We also describe unique sources of variability associated with data collection in the natural home environment.http://www.lenafoundation.org/TechReport.aspx/Reliability/LTR-05-1http://www.lenafoundation.org/TechReport.aspx/Reliability/LTR-05-1Wed, 17 Oct 2007 00:00:00 -0600Quantifying the accuracy and reliability of the LENA analysis software V2.3.0 is dependent on accurate and reliable transcription of the audio files by professional transcribers. Here, we disclose the analytical procedure designed and implemented by the LENA transcription team to identify and code speakers. Very good inter-rater reliability was achieved between the criterion rater and seven secondary raters. Inter-rater reliability was assessed through segment classification agreement. Significant accuracy in the transcriptions provided by professional raters was critical to train the processing models used to automatically identify segments in the audio file and to subsequently test the accuracy and reliability of the segmentation process.http://www.lenafoundation.org/TechReport.aspx/Transcription/LTR-06-1http://www.lenafoundation.org/TechReport.aspx/Transcription/LTR-06-1Wed, 17 Oct 2007 00:00:00 -0600The development of the LENA language environment analysis software V3.1.0 as well as quantifying its accuracy and reliability was dependent on the accurate and reliable transcription of the audio recording files by professional transcribers. In this report, we discuss the analytical procedure designed and implemented by LENA’s professional transcription team to identify and code speakers. We also reveal the degree to which inter-rater reliability was achieved between the criterion rater and four to seven secondary raters in terms of agreement for segment classification and adult word counts. Significant accuracy in the transcriptions was critical to train the processing models used to identify segments in audio recordings automatically and subsequently to test the accuracy and reliability of the segmentation process.http://www.lenafoundation.org/TechReport.aspx/Transcription/LTR-06-2http://www.lenafoundation.org/TechReport.aspx/Transcription/LTR-06-2Tue, 16 Sep 2008 00:00:00 -0600As part of the development of the LENA System, a team of LENA speech language pathologists, linguists, statisticians, and other researchers created the LENA Developmental Snapshot. This 52-item survey was designed to assess expressive and receptive language skills in children 2 months to 36 months of age and to estimate developmental age as a function of chronological age. In this report, we describe the development of the Developmental Snapshot. Initial respondents were drawn largely from the LENA Normative Study participant pool, and their scores were validated based on correlations with pre-existing standardized language and cognitive assessments. Participants in a longitudinal study completed the Developmental Snapshot at approximately monthly intervals to evaluate test-retest reliability.http://www.lenafoundation.org/TechReport.aspx/Snapshot/LTR-07-2http://www.lenafoundation.org/TechReport.aspx/Snapshot/LTR-07-2Tue, 16 Sep 2008 00:00:00 -0600As part of the development of the LENA System, the research and development team at LENA, consisting of speech language pathologists, linguists, statisticians and other researchers, created the LENA Developmental Snapshot (LDS). This 52-item Yes/No survey was designed to assess expressive and receptive language skills in children 2-36 months of age, and to estimate developmental age as a function of chronological age. Here we describe the development of the LDS. Initial respondents were drawn largely from the LENA Natural Language Study participant pool, and their LDS scores were validated based on correlations with pre-existing standardized language and cognitive assessments. Participants in a longitudinal phase of the LENA Natural Language Study completed the LDS at approximately monthly intervals to evaluate LDS test-retest reliability.http://www.lenafoundation.org/TechReport.aspx/Snapshot/LTR-07-1http://www.lenafoundation.org/TechReport.aspx/Snapshot/LTR-07-1Wed, 17 Oct 2007 00:00:00 -0600This report describes the development of the LENA Automatic Vocalization Assessment (AVA) software. AVA software was designed to provide both parents and professionals with automatically generated information about the expressive language development of children ages 2 months to 48 months. Expressive language estimates are produced based on 12- to 16-hour audio recordings collected in the natural home environment using the LENA language environment analysis system. AVA software uses automatic speech recognition technology to categorize and quantify the sounds in child vocalizations (e.g., protophones and phonemes). These quantitative acoustic information data (expressed as “phone” and “biphone” frequencies) are reduced to principal components which are applied as input for age-based multiple linear regression models. The AVA software utilizes these regression models to generate information about expressive language development as standard scores, developmental age estimates, and estimated mean length of utterance (EMLU). AVA expressive language estimates demonstrate statistical reliability and validity comparable to standard expressive language assessments commonly administered by speech language pathologists.http://www.lenafoundation.org/TechReport.aspx/AVA/LTR-08-1http://www.lenafoundation.org/TechReport.aspx/AVA/LTR-08-1Tue, 16 Sep 2008 00:00:00 -0600The LENA language environment analysis system is a powerful new tool that can help pediatricians, speech language pathologists, and audiologists improve their diagnosis and treatment of language delay and disorders, and increase parent involvement and satisfaction. Broadly speaking, the uses of LENA in clinical practice fall into four categories: 1) assessment and diagnosis, 2) monitoring fidelity of treatment, 3) audio environment analysis, 4) enhanced treatment through in-home feedback.http://www.lenafoundation.org/TechReport.aspx/ClinicalApps/LTR-09-1http://www.lenafoundation.org/TechReport.aspx/ClinicalApps/LTR-09-1Tue, 16 Sep 2008 00:00:00 -0600Autism Spectrum Disorders (ASD) are characterized by qualitative impairments in social interaction and communication as well as restricted and repetitive behaviors. The presence or absence of these behavioral signs underlies the criteria that clinicians use to assess children for ASD. However, the extensive training and expertise required to diagnose ASD and the sometimes incomplete nature of available information can limit the efficiency and reliability of screening using traditional indicators, especially at younger ages. Going beyond established diagnostic criteria, researchers have reported atypicality in the vocal production of children with ASD for features such as duration, pitch, and rhythm. Such anomalies potentially carry important diagnostic information, but on a practical level the means to explore this possibility in greater detail have been lacking. In particular, the identification of vocal features characteristic of ASD has been limited by the need to rely on resource-intensive expert judgment and the difficulty of obtaining, processing, and interpreting representative audio samples of sufficient quality and quantity. Here we report on the development and performance of a fully automatic and objective method that utilizes recent advances in technology to collect child vocalizations in large volume and evaluate discriminative vocal characteristics that could be used to help identify children at risk for ASD. http://www.lenafoundation.org/TechReport.aspx/LAAS/LTR-10-1http://www.lenafoundation.org/TechReport.aspx/LAAS/LTR-10-1Thu, 02 Sep 2010 16:39:51 -0600The LENA System is the world’s only technology capable of automatically and objectively monitoring and assessing the natural language environments of infants and toddlers. The most advanced product in the LENA System portfolio, LENA Pro enables researchers, speech-language pathologists (SLPs), audiologists, and pediatricians to collect, manage, and analyze multiple recordings of children ages 2 months to 48 months. LENA Pro reports offer count and percentile data on speech language measurements, such as estimates of adult words spoken to and around the key child (i.e., the child wearing the LENA Digital Language Processor – DLP), adult-child conversational interactions, and child vocalizations. The system also segments and labels audio waveforms and can be used to conduct advanced analyses when used with the LENA Advanced Data Extractor (ADEX).http://www.lenafoundation.org/TechReport.aspx/LPB/LTR-11-1http://www.lenafoundation.org/TechReport.aspx/LPB/LTR-11-1Thu, 11 Aug 2011 13:15:29 -0600