Speech Perception & Acoustics Laboratories
The Speech Perception & Acoustics Laboratories (SPA Labs) are a research unit affiliated with the Department of Speech and Hearing Science. The current research program consists of several projects in speech communication which underscore the importance of variation in speech. The variation comes from diverse sources such as speaker characteristics, the geographic region in which the speaker was raised, or from factors related to the dynamic character of broadly defined speech units. The approach taken at the SPA Labs is data-driven and the focus is on constructing large corpora of speech which would provide conclusive answers to the questions asked. The current research addresses several issues in human speech perception, acoustic amplitude variation in coarticulated vowels, dialectal variation in acoustic characteristics of speech, phonetic aspects of sound change, cognitive processing in individuals who stutter, and learning second language phonology.
In the Psychoacoustics Laboratory we are working on projects that investigate the ability of listeners to extract information from complex, time-varying sounds. These sounds are acoustically similar to speech, music or environmental sounds, but they do not require the cognitive processing necessary to recognize or understand those sounds. We are testing our model of peripheral auditory processing, which suggests that the auditory nervous system responds to the spectral center-of-gravity, COG, of the neural activity generated by such sounds. The COG is the “balance point” for this activity. As the COG changes over time, listeners hear changes in the sounds that are often described as rising or falling pitches.
The Speech Psychoacoustics Laboratory
Work performed in the Speech Psychoacoustics Laboratory seeks to clarify the processing mechanisms involved in human hearing, and the limitations to these mechanisms imposed by hearing impairment or cochlear prostheses. Relationships between basic psychoacoustic phenomena involving simple stimuli and the perception of complex signals such as speech are explored.
Children's Communication Laboratory
In this laboratory, we tackle diverse projects intended to improve the understanding, assessment and facilitation of children's normal and disordered communication. These projects address a wide range of developmental communication disorders (e.g., autism spectrum disorders and speech sound disorders, including childhood apraxia of speech). In addition, they address the methods and workplace environments of speech-language pathologists. Examples of recent completed and ongoing projects associated with the lab include:
- Comparison of the motor speech skills in children with high functioning autism and those with typical development and with motor speech disorders,
- Description of the clinical practices related to Autism Spectrum Disorder used by speech-language pathologists practicing in India,
- Systematic review of participant descriptions in research on children with Childhood Apraxia of Speech, and
- Understanding speech-language pathologists' work engagement, social supports and attitudes to their own workplace and professional issues using appreciative interviewing and surveys.
Childhood Cognition, Communication, and Brain Injury Lab
Research in the Childhood Cognition, Communication, and Brain Injury Lab (CABI Lab) focuses on improving outcomes for children and adolescents with acquired brain injury (ABI) and other complex medical conditions. Our work seeks to improve gaps in access to and utilization of services designed to support children with ABI and to identify specific approaches that would improve assessment and treatment practices following pediatric ABI. To inform our work in children with ABI, some of our research focuses on expanding our understanding of children with typical development in areas such as academic discourse.
Speech Recognition and Aging Laboratory
The Speech Recognition and Aging Laboratory (SR&A Lab), housed in the Department of Speech & Hearing Science, is dedicated to gaining a better understanding of the speech understanding problems exhibited by older adult listeners with hearing loss. There is a growing body of evidence that suggests older adults have difficulty processing binaural auditory information (i.e., binaural interference), especially in noisy listening environments. Current lab projects are focused on studying the binaural interference phenomenon among aging listeners.
Developmental Speech Lab
The Developmental Speech Lab seeks to better understand the development of speech perception and language in typically developing children and those with hearing loss, and, based on this knowledge, design better approaches to intervention and remediation. This work is inherently multidisciplinary and we collaborate with colleagues across the University and the country. Our current research focuses on the role of family environment in spoken language and executive function outcomes in children with hearing loss, basic speech perception in toddlers believed to have a core deficit in phonological encoding, and children’s ability to cope with variability in speech – specifically variability due to nonnative accents.
Auditory Physiology Lab
The Auditory Physiology Lab pursues research in the area of acquired sensorineural hearing loss from noise, drugs, and aging. We are interested in the biological mechanisms underlying the damage to the cochlea that leads to the sensorineural hearing loss. Noise, drugs, and aging have many common factors through which they create hearing loss, as well as many key differences. In addition, different types of hearing losses interact with each other, creating unique patterns of hearing loss and cochlear pathology. In addition to studying the mechanisms of hearing loss and interactions, we are working to develop new methods to detect hearing loss early, and to find new ways to protect the ear from hearing loss with different drugs and dietary supplements.
Child Language Ability (CLA) Lab
Research in the Child Language Ability (CLA) Lab addresses the role of language and literacy in educational disproportionality issues faced by African American children, who are overrepresented in special education programs and underrepresented in talented and gifted education programs. Research in the CLA lab centers on improving our ability to differentiate African American children who are language-impaired from those who are language normal, and those who are linguistically gifted. We are currently involved in three research projects. In the first project, we are developing culture-fair measures of oral and written narration. The second project investigates the underlying mechanisms for oral and print code-switching. Our third project examines the impact of social capital on language and literacy development. Students who join the CLA lab will develop transcription and coding skills, participate in lab meetings, and engage in other research tasks.
The Autism & Child Language Learning Lab
Research in the The Autism & Child Language Learning Lab examines the processes that underlie language development in children with and without autism spectrum disorders. The aim is to determine how similarities and differences in these underlying processes, such as attention and executive function, influence language development. This work will inform language intervention for children with autism spectrum disorders.
The Aphasia Laboratory investigates language processing after brain damage, specifically focusing on word-retrieval deficits. Research in this lab seeks to address limitations in aphasia treatment delivery including dosing of therapy, maintenance and generalization of treatment effects, and the neural substrates underlying aphasia rehabilitation.
Our research team in the Voice/Resonance Laboratory works towards understanding the anatomic, physiologic, and acoustic aspects of the normal and abnormal speech production mechanism, with special emphasis on voice and resonance, by combining bio-imaging techniques and acoustic analysis method. Current projects include identifying vital anatomic features that can serve as reliable prognostic indicators of the speech outcome in individuals with repaired cleft palate and assessing multi-dimensional outcomes of an intervention program used for individuals with hypernasality.
Crane Center For Early Childhood Research and Policy
Laura M. Justice, Ph.D.
The Crane Center for Early Childhood Research and Policy is a multidisciplinary research center dedicated to conducting high-quality research that improves children’s learning and development at home, in school and in the community. We partner with The A. Sophie Rogers School for Early Learning to provide effective, research-based curriculum that focuses on language and literacy development and building essential social skills. We also work with a network of community partners to provide early childhood programming and family engagement.