Mark Vandam

• PhD, Indiana University
• Professor (Associate) at Washington State University

Purpose The purpose of this work is to describe the conversation initiation rates in families of toddlers who are deaf and hard of hearing (DHH) as compared to those with typical development. Method Analysis of daylong acoustic recordings was used to describe the conversational dynamics in 78 families, comprising 51 families with a DHH toddler (23...

Purpose Down syndrome (DS) is associated with lifelong difficulties with verbal communication, beginning in infancy when vocalizations are sparse and first words emerge late. Because DS is diagnosed at or even before birth, these difficulties can be anticipated, yet there have been limited developments of systematic, proactive interventions. The pu...

Mothers and fathers modify prosodic characteristics of child-directed speech relative to adult-directed speech. Evidence suggests that mothers and fathers may differ in how they use child-directed speech as communicative partners. Thus, fathers create communicative challenges during father-child interaction that facilitate the child's adaptation to...

Purpose We sought to compare raw scores, standard scores, and age equivalences on two commonly used vocabulary tests, the Peabody Picture Vocabulary Test (PPVT) and the Receptive One-Word Picture Vocabulary Test (ROWPVT). Method Sixty-two children, 31 with hearing loss (HL) and 31 with normal hearing (NH), were given both the PPVT and ROWPVT as pa...

Purpose Babble Boot Camp (BBC) is a parent-implemented telepractice intervention for infants at risk for speech and language disorders. BBC uses a teach–model–coach–review approach, delivered through weekly 15-min virtual meetings with a speech-language pathologist. We discuss accommodations needed for successful virtual follow-up test administrati...

Purpose Precision medicine is an emerging intervention paradigm that leverages knowledge of risk factors such as genotypes, lifestyle, and environment toward proactive and personalized interventions. Regarding genetic risk factors, examples of interventions informed by the field of medical genomics are pharmacological interventions tailored to an i...

Children who are deaf/hard of hearing (D/HH) have lower performance on test of phonological awareness, particularly phoneme-level tasks, than children with normal hearing. These performance deficits have been seen both in children who use cochlear implants (CIs) and children who use hearing aids (HAs), but few studies have explicitly compared the e...

Speech problems affect about 66% of children with classic galactosemia (CG), but limited evidence is reported on early motor and sensory motor development in this at-risk population. Research has been focused on speech and language development, leaving a paucity of data on motor and sensory differences. This paper describes preliminary data regardi...

Recent work has shown that preschool children initiate more conversations than their mothers and fathers. It has also been shown that boys and girls initiate conversations at about the same rate. It is not known if children with hearing loss initiate conversations at comparable rates to their typically-developing peers, or whether boys and girls wi...

Purpose: We sought to compare raw scores, standard scores, and age equivalences on two commonly used vocabulary tests, the Peabody Picture Vocabulary Test (PPVT) and the Receptive One Word Picture Vocabulary Test (ROWPVT).Method: Seventy-one children, 36 with hearing loss and 35 with normal hearing, were given both the PPVT and ROWPVT as part of an...

Purpose This study evaluated the feasibility of Babble Boot Camp (BBC) for use with infants with classic galactosemia (CG) starting at less than 6 months of age. BBC is a parent-implemented intervention delivered by speech-language pathologists (SLPs) entirely via telepractice with the potential to increase access to early preventative intervention...

Precision medicine is an emerging approach to managing disease by taking into consideration an individual’s genetic and environmental profile toward two avenues to improved outcomes, prevention and personalized treatments. This framework is largely geared to conditions conventionally falling into the field of medical genetics. Here, we show that th...

In a conversational exchange, interlocutors use social cues including conversational turn-taking to communicate. There has been attention in the literature concerning how mothers, fathers, boys, and girls converse with each other, and in particular who initiates a conversation. Better understanding of conversational dynamics may deepen our understa...

Purpose Babble Boot Camp (BBC) is a package of proactive activities and routines designed to prevent speech and language disorders in infants at predictable risk. It is implemented via parent training and currently undergoing clinical trial in children with a newborn diagnosis of classic galactosemia (CG), a metabolic disease with high risk of spee...

Objective: Vocal turn-taking is an important predictor of language development in children with and without hearing loss. Most studies have examined vocal turn-taking in mother-child dyads without considering the multitalker context in a child's life. The present study investigates the quantity of vocal turns between deaf and hard-of-hearing child...

Maximum tongue strength, mean swallow pressures, and tongue endurance were measured in 324 children ages 6–12 years. The purpose of this study was to measure saliva swallow pressures in absolute terms (i.e., kilopascals) and as a percentage of maximum tongue strength to determine functional reserve in across ages in children and to examine factors...

Zipf’s law describes the relationship between the frequencies of words in a corpus and their rank. Its most basic form is a simple series, indicating that the frequency of a word is inverselyproportional to its rank:1/2, 1/3, 1/4,...The past two decades have seen the emergence of usage-based and cognitive approaches to language study. A key observa...

No PDF available ABSTRACT How does hearing loss affect vocal turn-taking within families? This study examined turn-taking between children and multiple members of their social environment. For children with hearing loss, we also examined potential differences by device, hearing aids (HA) versus cochlear implants (CI). Daylong audio recordings were...

No PDF available ABSTRACT Children's ability to perceive auditory signals impacts speech and language development, cognition, academic performance, and social relationships. Vocal signals in the family environment produced by mothers, fathers, and children have different characteristics and likely contribute differently to development. Childhood he...

Background: Speech and language therapy is typically initiated reactively after a child shows delays. Infants with classic galactosemia (CG), a metabolic disease with a known high risk for both speech and language disorders, hold the keys towards evaluating whether preventive treatment is effective when the risks are known at birth. We present pilo...

Background: Speech and language therapy is typically initiated reactively after a child shows delays. Infants with classic galactosemia (CG), a metabolic disease with a known high risk for both speech and language disorders, hold the keys towards evaluating whether preventive treatment is effective when the risks are known at birth. We present pilo...

Background: Speech and language therapy is typically initiated reactively after a child starts showing delays. Infants with classic galactosemia (CG), a metabolic disease with a known high risk for both speech and language disorders, hold the keys towards evaluating whether preventive treatment is effective when the risks are known at birth. We pre...

Long-term literacy outcomes for children with hearing loss, particularly those with severe-to-profound deafness who are fitted with cochlear implants (CIs) lag behind those of children with normal hearing (NH). The causes for these long-term deficits are not fully clear, though differences in auditory access between children who use CIs and those w...

Do children with hearing loss use infant-directed speech while addressing their normal-hearing (NH) infant siblings? This case-study examined speech characteristics in two age-matched children, one with severe-to-profound hearing loss who used bilateral cochlear implants (CIs) for 5 years (the CI child) and one NH child. Both children explained how...

Background: Speech or language therapy is typically initiated reactively after a child starts showing delays. Infants with classic galactosemia (CG), an inborn error of metabolism with a known high risk for both speech and language disorders, hold the keys towards evaluating whether preventive treatment is effective when the risks are known at birt...

Background and Objectives: This systematic review reports the evidence from the literature concerning the potential for using an automated vocal analysis, the Language ENvironment Analysis (LENA, LENA Research Foundation, Boulder, CO, USA) in the screening process for children at risk for autism spectrum disorder (ASD) and deaf or hard of hearing (...

Background: Speech or language therapy is typically initiated reactively after a child starts showing delays. Infants with classic galactosemia (CG), an inborn error of metabolism with a known high risk for both speech and language disorders, hold the keys towards evaluating whether preventive treatment is effective when the risks are known at birt...

HomeBank (https://homebank.talkbank.org/) is an online database of multi-hour, naturalistic audio recordings of child and family everyday experiences. Corpora in the database include (1) raw audio recordings; (2) corpus metadata including for example social details, standardized test scores, disability reports and status, family data such as number...

Children develop, learn, and refine the complex rules of how to have a conversation beginning in their preschool years. Recent work on conversational exchanges and language usage within families has shown differences (and in some cases, similarities) in how mothers, fathers, girls, and boys interact and converse with each other. It has been suggest...

Conversations between adults and children have been shown to be an important factor affecting the development of cognition, academic performance, and language use in children. Conversational exchange frequency between parents and children has been shown to increase with age. It has also been demonstrated that degraded sensory input, such as with he...

Do children with hearing loss use infant-directed speech? The study examined speech characteristics of a 6-year-old child with bilateral cochlear implants and an age-matched child with normal-hearing while interacting with their infant siblings (age 29 and 20 months) and with their mothers. Child-sibling and child-mother interactions were recorded...

Expressive language in preschoolers has been shown to be positively related to later language development, although not all studies have shown robust effects. Most studies that consider sex have shown that girls develop expressive language earlier than boys. It has also been widely demonstrated that children with a variety of speech-, language-, an...

Purpose The purpose of this cross-sectional investigation was to expand the comparative database of pediatric tongue strength for children and adolescents with typical development, ages 3–17 years, and compare tongue strength among children with typical development, speech sound delay/disorders (SD), and motor speech disorders (MSDs). Method Tongu...

We explore here the application of modern computer hardware and software to the collection and analysis of behavioral data. We discuss the issues of ecological validity, storage and processing, data permanence, automation, validity, and algorithmic determinism. Taking the modern landscape into account, we demonstrate several varying projects we hav...

Pupillometry, a method for indirectly measuring neural firing within the locus-coeruleus norepinephrine (LC-NE) system, has long been used to examine visual attention, serving as a proxy for measuring arousal and attention. In recent years, it has been established that changes in pupil dilation is associated with cognitive demand in typical populat...

Syllables play an important role in speech synthesis, speech recognition, and spoken document retrieval. A novel, low cost, and language agnostic approach to dividing words into their corresponding syllables is presented. A hybrid genetic algorithm constructs a categorization of phones optimized for syllabification. This categorization is used on t...

Syllables play an important role in speech synthesis, speech recognition, and spoken document retrieval. A novel, low cost, and language agnostic approach to dividing words into their corresponding syllables is presented. A hybrid genetic algorithm constructs a categorization of phones optimized for syllabification. This categorization is used on t...

Linguistic complexity is an indicator of language development in young children. Complexity of a child’s linguistic productions have been shown to increase with development, but may be affected by factors such as disability or environmental variables. Here, we look into the role of family composition as a possible influence on a child’s developing...

Linguistic type-frequency, how many different lexical types are used, has been examined in usage-based models of child language acquisition. In general, it has been shown that exposure to greater type-frequencies increases children’s productive use of language and that language in turn bootstraps later development including language and literacy. I...

Lay summary: Milder forms of autism spectrum disorder (ASD) can be difficult to diagnose based on behavioral testing alone. This study used eye-tracking equipment and a hand-held penlight to measure the pupil reflex in adolescents with "high functioning" ASD and in adolescents without ASD. The ASD group showed a delay in pupil response. This is th...

Very little is known about the acoustic characteristics of the daylong auditory environment of children, especially for those children who belong to an at-risk population such as those with hearing loss. This work looks at the daylong acoustic amplitude from the auditory perspective of young children. Naturalistic audio was collected from a wearabl...

In a natural family environment, fathers have been shown to talk less than mothers, and fathers may talk more to sons than to daughters. There is conflicting evidence showing mothers’ word use increases talking both to sons and to daughters. Further, preschoolers who are hard-of-hearing have been shown to encounter a similar number of parent uttera...

Automatic speech processing (ASP) has recently been applied to very large datasets of naturalistically collected, daylong recordings of child speech via an audio recorder worn by young children. The system developed by the LENA Research Foundation analyzes children's speech for research and clinical purposes, with special focus on of identifying an...

HomeBank is introduced here. It is a public, permanent, extensible, online database of daylong audio recorded in naturalistic environments. HomeBank serves two primary purposes. First, it is a repository for raw audio and associated files: one database requires special permissions, and another redacted database allows unrestricted public access. As...

The literature on child-directed speech has shown that mothers, on average, talk to their children with higher token frequency than fathers, but fathers may use more complex language or more variable word types. Other recent research has shown that mothers may use greater fundamental frequency variability and range when talking to their children, a...

In a natural family environment, fathers tend to talk less than mothers, and possibly more to sons than to daughters. There is conflicting evidence showing mothers’ word use with sons and daughters. Further, preschoolers who are hard-of-hearing have been shown to encounter a similar number of parent utterances as compared with their typically-devel...

Trumpet players produce and manipulate sound through their instrument by articulating the lips, cheeks, and tongue to create a proper airflow. These sustained muscle contractions may result in increased facial and lingual strength and endurance. The purpose of this study was to determine if adult trumpet players who practice at least 6 hrs/wk diffe...

Studies of motherese or child-directed speech (CDS) have paid scant attention to fathers' speech when talking to children. This study compares mothers' and fathers' use of CDS in terms of fundamental frequency (F 0) production, examining natural speech from a very large database of hundreds of hours of family speech including mothers...

Studies of child-directed speech (CDS) have shown that when talking to children, parents systematically use (among other strategies) increased fundamental frequency (F 0). Lombard effects such as increased F 0 have also been documented when addressing a listener who is hard-of-hearing (HH). Here, we examine F 0 of mothers and fathers in families wi...

This study investigated automatic assessment of vocal development in children with hearing loss compared with children who are typically developing, have language delays, and have autism spectrum disorder. Statistical models are examined for performance in a classification model and to predict age within the four groups of children. The vocal analy...

There has been increasing attention in the literature to wearable acoustic recording devices, particularly to examine naturalistic speech in disordered and child populations. Recordings are typically analyzed using automatic procedures that critically depend on the reliability of the collected signal. This work describes the acoustic amplitude resp...

Performance of an automatic speech recognition (ASR) system [LENA Research Foundation, Boulder, CO] has been reported for naturalistic, whole day recordings collected in families with typically developing (TD) children. This report examines ASR performance of the LENA system in families with children who are hard-of-hearing (HH). Machine-labeled se...

The objectives of this study were to examine the quantity of adult words, adult-child conversational turns, and electronic media in the auditory environments of toddlers who are hard of hearing (HH) and to examine whether these factors contributed to variability in children's communication outcomes. Participants were 28 children with mild to severe...

In a previous report [VanDam and Silbert (2013) POMA 19, 060006], we investigated performance of a commercially available automatic speech recognition (ASR) system [LENA Research Foundation, Boulder, CO] on acoustic recordings from family speech in naturalistic environments. We found that the ASR more accurately labeled children over adults and fat...

Repetitive use of specific muscle groups is known to increase both strength and the ability to sustain muscle activity (i.e., endurance) of those muscle groups. Certain orofacial muscles are necessarily recruited in the course of playing a brass instrument, and thus regular performers may incidentally gain strength and endurance in the orofacial mu...

A body-worn, real-time speech and voice biofeedback device is described. Data from an acoustic microphone and piezoelectric sensor worn comfortably in a neckband are streamed to a digital signal processor and a small, mobile computer, altogether able to fit into a pocket for extended use. User laryngeal and spectral characteristics are determined f...

Automatic speech recognition (ASR) software developed by the LENA Research Foundation (Boulder, CO) is an increasingly important tool in psycholinguistics. Naturalistic day-long recordings are segmented and assigned talker labels including those for KEY CHILD, ADULT MALE, and ADULT FEMALE. Performance of the system is a serious concern for ASR in g...

Experimental speech research often makes use of complex experimental designs, but even when multiple experimental factors are manipulated, measured outcomes may be influenced by non-controlled and incompletely controlled factors. Multilevel models (of which mixed-effect models are a special case) enable unified analysis of the relationships between...

Age, hearing loss, and phonological neighborhood density have been shown to substantially affect the accuracy of productions in a word imitation task [VanDam, et al., 161st ASA Meeting]. Older children (7 years of age) are more accurate than younger children (4 years of age), normal hearing children are more accurate than children with mild- to sev...

Automated analyses of full-day recordings were used to determine whether young children who are hard-of-hearing (HH) received similar levels of exposure to adult words and conversational interactions as age-matched peers with normal-hearing (NH). Differences in adult input between children in this study and in a normative database were considered....

4 and 7 year‐old children with normal and impaired hearing performed a listen‐and‐repeat task with words from dense and sparse phonological neighborhoods. Response accuracy was measured as a function of age, hearing loss, and neighborhood density. Accuracy was higher for older children, children with normal hearing, and for words from dense phonolo...

The current longitudinal project examines speech and language development in 40 preschool children with mild? to severe?hearing loss (and a cohort of typically developing peers) as part of large, multicenter project on outcomes of children with hearing loss. Whole?day recordings are collected once monthly for 1 year and subjected to detailed acoust...

This work investigates the developmental aspects of the duration of point vowels in children with normal hearing compared with those with hearing aids and cochlear implants at 4 and 5 years of age. Younger children produced longer vowels than older children, and children with hearing loss (HL) produced longer and more variable vowels than their nor...

Advances in hearing science have dramatically reduced the age of identification of hearing loss (HL) and improved intervention strategies, especially amplification methods. As a result, children with HL have earlier, better auditory access. How this early auditory experience affects language and speech abilities is not fully understood. This study...

Technological advances in the last 15 years have resulted in earlier identification of children with mild and moderate hearing loss. Little is known about the impact of early provision of amplification on the development of prosodic speech characteristics such as fundamental frequency (F0). This study aims to address that gap. Children enter this s...

Talkers performed a listen-and-repeat task to investigate temporal detail in voice-onset time (VOT) productions of American English word-initial stop consonants. Experimental factors included linguistic context (isolation, carrier phrase, unfamiliar phrase, and familiar phrase), usage frequency (high and low), lexical status (word and non-word), tr...

Visual information plays an important role in the perception of speech. Many studies have shown that the addition of visual information increases speech intelligibility, and that the visual channel alone (as in the case of speechreading) is capable of conveying meaning. The goal of this study was to examine whether children with hearing loss use vi...

Voice‐onset time (VOT) in English maps onto the phonological categories voiced or voiceless, but fine‐grained control of VOT production may vary as a function of additional linguistic features (e.g., lexical frequency, phrasal context, indexical features). This study investigated the patterns of VOT production in words that varied (a) by lexical us...

How does experience with specific words influence linguistic-phonetic categories? Listeners were trained over a five-session, listen-and-repeat task on a set of target words embedded in continuous speech and altered so that the initial stop consonant voice-onset time (VOT) was 80% longer than natural. Voicing boundaries were estimated before and af...

This longitudinal study examined the development of temporal speech properties in hearing impaired and normal hearing children at 4 and 5 years of age. Children repeated a list of target words following the experimenter's model. Measures of duration for onset, nucleus, coda, and syllable were collected for children with normal hearing and children...

Frequency of occurrence is known to have many effects on speech production [see J. Bybee, Phonology and Language Use (Cambridge, 2001)] including vowel quality, overall duration, rate of deletion, assimilation, coarticulation, etc. The current work addresses voice‐onset time (VOT) in words with differing lexical frequency estimates from published m...

Language families were chosen based on the classification of Ruhlen (1987) in order to determine the number and kind of word final coda types languages tend to permit. It was found that lan- guages tend to prefer fewer word final segments. Indeed, the ex- treme case is that which allows no word final consonants at all, a very common description of...