CONTRIBUTIONS OF TALKER AND LISTENER FACTORS TO SPEECH PERCEPTION AND FUNCTIONAL HEARING IN CHILDREN

PROJECT SUMMARY/ABSTRACT The ability to hear and recognize speech in complex auditory scenes follows a prolonged time course of development that extends into the second decade of life. Prior research has led to the identification of key factors that support maturation of functional hearing skills, has yielded a solid theoretical framework for understanding auditory development for a subset of conditions, and has allowed us to establish feasible procedures for collecting reliable behavioral data across a wide range of age groups and listener demographics. However, most of what we know about development of functional hearing is based on a relatively homogeneous subpopulation of children with easy access to the laboratory, assessed under a limited set of conditions. Our work in this area has progressed to the stage where we can leverage our methods and models to understand auditory development across a more inclusive sample of children using speech stimuli that capture the acoustic variability children experience in their daily lives. The project has three specific aims. The first aim evaluates the influence of listening to speech produced under more natural conditions than recordings used previously in auditory research. Experiments assess children’s speech recognition abilities using three types of speech: 1) speech produced by a talker with an unfamiliar accent; 2) speech produced by a talker using a conversational speaking style; and 3) speech produced a young child. The second aim tests the hypothesis that a main contributor to children’s pronounced difficulties understanding speech in dynamic, multisource acoustic environments reflects immaturity in the ability to adapt to changes in the acoustic environment and selectively allocate attention. Experiments in this aim evaluate the ability to adapt to a novel talker’s voice and focus their attention to a specific target or location in space. The third aim measures masked speech recognition, spatial release from masking, and masked talker localization in a large group of children who vary with respect to age, socioeconomic status, rurality, hearing sensitivity, and language proficiency. Testing is conducted at community sites inside our mobile research trailer, reducing some of the barriers to participating in research. The results generated by this project are expected move us closer to understanding the factors that influence hearing and communication for a more diverse range of children and target stimuli. This focus on inclusion is timely given the growing awareness that we must improve access to healthcare and educational opportunities for our most vulnerable children.