Christopher A Moore

Boston University | BU · College of Health and Rehabiliation Sciences: Sargent College

Purpose: The purpose of the study was to determine whether distinct subgroups of preschool children with speech sound disorders (SSD) could be identified using a subgroup discovery algorithm (SUBgroup discovery via Alternate Random Processes, or SUBARP). Of specific interest was finding evidence of a subgroup of SSD exhibiting performance consiste...

Purpose: In this study, the authors compared indirect estimates of jaw-muscle tension in children with suspected muscle-tone abnormalities with age- and gender-matched controls. Method: Jaw movement and muscle activation were measured in children (ages 3 years, 11 months, to 10 years) with suspected muscle-tone abnormalities (Down syndrome or sp...

Three- to five-year-old children produce speech that is characterized by a high level of variability within and across individuals. This variability, which is manifest in speech movements, acoustics, and overt behaviors, can be input to subgroup discovery methods to identify cohesive subgroups of speakers or to reveal distinct developmental pathway...

The mandible is often portrayed as a primary structure of early babble production, but empiricists still need to specify (a) how mandibular motor control and kinematics vary among different types of multisyllabic babble, (b) whether chewing or jaw oscillation relies on a coordinative infrastructure that can be exploited for early types of multisyll...

Conceptual and methodological confounds occur when non(sense) word repetition tasks are administered to speakers who do not have the target speech sounds in their phonetic inventories or who habitually misarticulate targeted speech sounds. In this article, the authors (a) describe a nonword repetition task, the Syllable Repetiton Task (SRT), that e...

This investigation explored whether meaningful subgroups of children would emerge from a heterogeneous population of typical preschool speakers as a result of convergences of measures from multiple speech production subsystems: behavioral, phonatory, articulatory, and respiratory. Because variability is a ubiquitous characteristic of preschool spee...

This article addresses a long-standing clinical and theoretical debate regarding the potential relationship between speech and nonspeech behaviors in the developing system. The review is motivated by the high popularity of nonspeech oral motor exercises (NSOMEs), including alimentary behaviors such as chewing, in the treatment of speech disorders i...

The present investigation was designed to study the modulation of abdomen and rib cage movements during vocalization over a period of development associated with rapid decreases in the compliance of the chest wall. Rib cage and abdominal kinematics were recorded during spontaneous vocalizations in 7- and 11-month old infants. Principal component an...

The ontogeny of mandibular control is important for understanding the general neurophysiologic development for speech and alimentary behaviors. Prior investigations suggest that mandibular control is organized distinctively across speech and nonspeech tasks in 15-month-olds and adults and that, with development, these extant forms of motor control...

The movement of the jaw during speech and chewing has frequently been studied by tracking surface landmarks on the chin. However, the extent to which chin motions accurately represent those of the underlying mandible remains in question. In this investigation, the movements of a pellet attached to the incisor of the mandible were compared with thos...

The National Alliance Promoting Research in Allied Health (NAPRAH) was formed in the fall of 2003 as a grassroots, interdisciplinary effort to address research capacity in the allied health professorate. The founders of this organization recognized the following as its rationale: • Enhance and synergize the allied health sciences and professions th...

As part of a large‐scale study that aims to create a data‐driven model of speech delay of unknown origin (SD) in preschool children, this investigation analyzed two‐ and three‐syllable nonword repetitions by 50 3‐ to 5‐year‐old children, half of whom are typically developing (TD). The syllable repetition task was composed of four different words, b...

This study examined the relationship between acoustic correlates of stress in trochaic (strong-weak), spondaic (strong-strong), and iambic (weak-strong) nonword bisyllables produced by children (30-50) with normal speech acquisition and children with speech delay. Ratios comparing the acoustic measures (vowel duration, rms, and f0) of the first syl...

Few empirical findings or technical guidelines are available on the current transition from analog to digital audio recording in childhood speech sound disorders. Of particular concern in the present context was whether a transition from analog- to digital-based transcription and coding of prosody and voice features might require re-standardizing a...

Oronasal coupling in young children remains poorly understood primarily because of experimental challenges associated with non‐invasive techniques for transducing velopharyngeal movement. Productions of the word [bama] were studied in children with normal speech acquisition (NSA) and children with speech delay (SD; 3‐to‐5 years of age) with respect...

This study was designed to evaluate the control of jaw movement in contrastive stress productions of children with and without speech delay. The spatiotemporal index (STI) was used to calculate variability in jaw movement trajectories in 12 children producing three different metrical forms of CVCV syllables (trochaic, iambic, and even stress; papa,...

The development of respiratory drive for vocalization was studied by observing chest wall kinematics longitudinally in 4 typically developing children from the age of 9 to 48 months. Measurements of the relative contribution of rib cage and abdominal movement during vocalization (i.e., babbling and true words) and rest breathing were obtained every...

Masticatory muscle contraction causes both jaw movement and tissue deformation during function. Natural chewing data from 25 adult miniature pigs were studied by means of time series analysis. The data set included simultaneous recordings of electromyography (EMG) from bilateral masseter (MA), zygomaticomandibularis (ZM) and lateral pterygoid muscl...

Dworkin et al. comment: We would like to comment on Green, Moore, and Reilly’s article, which appeared in the February 2002 issue of this journal [Journal of Speech, Language, and Hearing Research]. In that investigation, these clinical researchers examined upper lip, lower lip, and mandibular movements during repetitive bisyllable word productions...

The amplitude of the respiratory sinus arrhythmia (RSA) was investigated during a reading aloud task to determine whether alterations in respiratory control during speech production affect the amplitude of RSA. Changes in RSA amplitude associated with speech were evaluated by comparing RSA amplitudes during reading aloud with those obtained during...

In the absence of voicing, the discrimination of "voiced" and "voiceless" stop consonants in whispered speech relies on such acoustic cues as burst duration and amplitude, and formant transition characteristics. The articulatory processes that generate these features of whispered speech remain speculative. This preliminary investigation examines th...

Vertical displacements of the upper lip, lower lip, and jaw during speech were recorded for groups of 1-, 2-, and 6-year-olds and adults to examine if control over these articulators develops sequentially. All movement traces were amplitudeand time-normalized. The developmental course of upper lip, lower lip, and jaw control was examined by quantif...

Research has shown that swallowing in adults is affected by bolus consistency. Little is known, however, regarding the effect of bolus consistency on swallowing in children. Electromyographic (EMG) data from typically developing five- and eight-year-old-children and adults were obtained from the following muscles as they swallowed boluses of differ...

Speech motor control emerges in the neurophysiologic context of widely distributed, powerful coordinative mechanisms, including those mediating respiratory function. It is unknown, however, whether developing children are able to exploit the capabilities of neural circuits controlling homeostasis for the production of speech and voice. Speech and r...

This investigation was designed to describe the development of lip and jaw coordination during speech and to evaluate the potential influence of speech motor development on phonologic development. Productions of syllables containing bilabial consonants were observed from speakers in four age groups (i.e., 1-year-olds, 2-year-olds, 6-year-olds, and...

This investigation was designed to describe the development of lip and jaw coordination during speech and to evaluate the potential influence of speech motor development on phonologic development. Productions of syllables containing bilabial consonants were observed from speakers in four age groups (i.e., 1-year-olds, 2-year-olds, 6-year-olds, and...

Infant-directed speech is an important but difficult-to-measure aspect of caregiver-infant interaction. Specialized training in speech science is required and processing is computationally intensive and time consuming. We developed a computer-assisted method of measuring infant-directed speech that requires little specialized training, has high con...

Little is known about visual cues that are critical to the accurate categorization, and perceived quality, of individual phonemes. The current study provided a preliminary evaluation of the relationship between orofacial movements and visual perception of phonemes distinguished by place of articulation. A female talker produced VCV utterances for /...

This investigation was designed to quantify the coordinative organization of lip muscle activity of 2-year-old children during speech and nonspeech behaviors. Electromyographic (EMG) recordings of right upper and lower lip activity of seven 2-year-old children were obtained during productions of chewing, syllable repetition, lip protrusion, and spe...

Developmental changes in the coordinative organization of masticatory muscles were examined longitudinally in four children over 49 experimental sessions spanning the age range of 12-48 mo. Electromyographic (EMG) records were obtained for right and left masseter muscles, right and left temporalis muscles, and the anterior belly of the digastric. T...

This investigation was designed to quantify the coordinative organization of mandibular muscles in toddlers during speech and nonspeech behaviors. Seven 15-month-olds were observed during spontaneous production of chewing, sucking, babbling, and speech. Comparison of mandibular coordination across these behaviors revealed that, even for children in...

To assess the relative contribution of dynamic and summary features of vocal fundamental frequency (f0) to the statistical discrimination of pragmatic categories in infant-directed speech, 49 mothers were instructed to use their voice to get their 4-month-old baby's attention, show approval, and provide comfort. Vocal f0 from 621 tokens was extract...

Fundamental frequency (f0) contours derived from the speech of 35 mothers to their 4-month-old infants were quantified for two experimental conditions, one in which the mother was instructed to seek her infant's attention and a second in which the mother was instructed to express approval of her infant's action. In addition to conventional descript...

Electromyographic activity of bilateral mandibular muscle pairs in humans was studied during several tasks: mastication, voluntary oscillation of the jaw, and speech production, as a replication and extension of an earlier investigation by Moore, Smith, and Ringel (1988). The synchrony of activity within and across these paired muscles (masseter, m...

Recent investigations (Cranford, Boose, & Moore, 1990a,b; Moore, Cranford, & Rahn, 1990) studied the ability of normal adult subjects to localize sounds under conditions that elicit the Precedence Effect. In different tests, subjects were required either to report the perceived location of a stationary fused auditory image (FAI) or track the appare...

The increasing availability of magnetic resonance imaging (MRI) as a research, and even clinical, tool in speech production makes possible a wide range of quantitative methods in vocal tract measurement. In these initial stages of application, it is essential that the limits of the method be identified. The present investigation was designed to app...

The precedence effect in sound localization can be evoked by presenting identical sounds (e.g., clicks) from pairs of loudspeakers placed on opposite sides of a subject's head. With appropriate inter-loudspeaker delays, normal subjects perceive a fused image originating from the side of the leading loudspeaker. Separate tests at loudspeaker delays...

The precedence effect in sound localization involves presenting identical sounds (e.g., clicks) from pairs of matched speakers situated on opposite sides of a subject's head, with the clicks from one speaker preceding those from the other by a short interval. With appropriate delays, normal subjects perceive a fused image which originates from the...

Language-impaired children have been shown to exhibit a variety of post-sentence comprehension deficits. Comprehension, however, may also be assessed as it develops rather than after it has occurred. The present investigation compared the real-time language processing abilities of language-impaired and normal children using a word recognition react...

Pursuit auditory tracking of a fused auditory image (FAI), based on stimulus conditions known to elicit the precedence effect phenomenon in sound localization, was investigated in 36 normal subjects and in a small group of subjects with known neuropathology. Movement of the FAI was simulated by incrementally varying the delay between two clicks pre...

Coordination of jaw muscle activity for speech production sometimes has been modeled using nonspeech behaviors. This orientation has been especially true in representations of mandibular movement in which the synergy of jaw muscles for speech production has been suggested to be derived from the central pattern generator (CPG) for chewing. The prese...

Reflex responses recorded from the upper and lower divisions of the human orbicularis oris muscle were studied as a function of the site of stimulation. Stimuli were applied to 11 sites, ranging from the glabrous skin of the upper and lower lip vermilion borders to the hairy skin of the cheek. Highly localized, innocuous mechanical stimuli were cre...

Jaw-closing force was transduced while subjects maintained a biting force of 9.8 N. To estimate the amplitude of tremor in each subject's force record, the average spectrum of the force was computed, and the definite integral of the averaged spectrum in the frequency range from 3.5 to 10 Hz was calculated. For the same subjects, the amplitude of re...

Innocuous mechanical stimuli were applied to eight sites on the tongue dorsum and palate while subjects used feedback to maintain a constant isometric biting force. Reflex responses of the jaw-closing system were measured as changes in force and in EMGs recorded from right and left masseter muscles. Stimulation at each of the eight sites produced r...

In the present study homonymous and heteronymous projections of muscle spindle afferent fibers in the human jaw-closing system were investigated. Stretch reflex responses were elicited with percutaneous displacement stimuli applied to the belly of the anterior superficial divisions of temporalis and masseter muscles. The distribution of reflex resp...

The role played by reflex pathways in the production of movement has been a significant issue for motor control theorists interested in a wide variety of motor behaviors. From studies of locomotion and chewing, it appears that gains in reflex pathways can be altered so that activity in these pathways does not produce destabilizing responses during...