This page's main content:

Special Lecture.

The development of mother-infant vocal interaction

Dr. Nick Smith

May 16, 2008 at 1 pm

HPER 206

 

Dr. Nicholas Smith, from Boys town National Research Hospital, will speak on Friday, May 16. His presentation is titled “The development of mother-infant vocal interaction” and will begin at 1 p.m. in HPER room 206 as part of the HPER Biomechanics Journal Club.

Dr. Smith, presently is a Staff Scientist, Coordinator in the Perceptual Development Laboratory. His research focuses on behavioral methods to study the development of infants’ perceptual and cognitive processing of sounds, such as speech, music, and complex tone patterns. Dr. Smith obtained his PhD in Psychology during 2004 from the University of Toronto in Canada. Previous to his appointment at Boys Town National Research Hospital in 2007 he was a Postdoctoral Fellow at McMaster University in the Department of Psychology, Neuroscience and Behaviour.

The HPER Biomechanics Laboratory invites anyone interested in Dr. Smith’s presentation to join us. This is a free event open to the University community. A short social will follow in our laboratory. For more information, please contact Lisa Holst, Project Assistant for the HPER Biomechanics Laboratory at 554-3075 or lholst@mail.unomaha.edu. More information about Nick Smith, PhD can be found at: http://www.nicholasasmith.com

Areas of Research

Clinical and Behavioral Studies of Human Communication

Perceptual Development Laboratory

Overview

The goal of research in this lab is to understand listeners’ ability to make sense of complex sounds, and to understand how this ability develops starting in infancy. These questions are explored in different domains. Infant-directed speech (‘babytalk’  or ‘motherese’), music, and other complex auditory patterns contain rich temporal and pitch information that infants must resolve, encode and process in order to make sense of these signals. Infants’ perceptual abilities are tested using a variety of behavioral methods. Other studies examine speech production in mother-infant dyads, using acoustical analyses to track the developmental changes in the pitch and temporal properties of mother-infant interaction.

Facilities

The laboratory consists of a sound attenuated booth, a control room, and workspace for research assistants. The booth is set up to test infants in a variety of behavioral paradigms (e.g., conditioned head-turn and preference procedures), including eye-tracking (using a faceLAB 4.5 system). Auditory and visual stimuli are presented via GSI speakers and three LCD display controlled by a PowerMac computer in the adjacent control room. Max/MSP software is used for real-time signal processing, presenting stimuli, recording responses, and the coordination of other aspects of the experimental procedures. The laboratory also contains iMac computers for recording and analyzing audio/video infant interactions, using Praat.

Staff

This lab is directed by Nicholas Smith, Ph.D, and benefits from collaboration with Mary Pat Moeller, Ph.D. and Mark VanDam, Ph.D. http://www.vandammark.com

Summary of Research Program

For Clinicians and Scientists

            Temporal processing and perceptual organization. The sound patterns of speech and music consist of rapid changes in the energy in different frequency regions. The auditory system has been characterized as an array of frequency tuned channels. The central auditory processes responsible for analyzing the auditory scene and perceiving patterns must resolve and integrate information across these channels in order to accurately represent the stimulus or sound source. Our research uses gap detection and temporal order judgment tasks to examine these between-channel processes, and how they are affected by stimulus, context, and task related factors, as well as perceptual learning and development.

            Mother-infant speech interaction. Infant-directed (ID) speech exhibits characteristic prosodic modifications: higher overall pitch, expanded pitch range, increased repetition, extended pause. Infants have strong preferences for ID speech and respond in ways that promote this of kind of interaction. The main goals of our research are to examine (1) how mothers’ ID speech changes over the course of development, and how it may be affected by hearing loss in the child, (2) the development of prosody in children with normal hearing and with hearing loss and (3) the rhythmic aspects of mother-child vocal interaction.

For Families

Temporal processing and perceptual organization. Being able to hear is the first step toward making sense of sound. In the real world, we hear rapidly changing combinations of sounds from different sources (e.g., a group of people talking on a busy city street). Central auditory processing in the brain needs to sort this auditory input and figure out which “pieces” go together, and how.

Mother-infant speech interaction. When adults talk to infants and children, their speech speech becomes more “musical.” This serves a number of functions in development. It helps to regulate the infants’ emotions, but may also help infants to better perceive speech and learn language. Our research examines how this musical aspect of speech changes over the course of development, and how these changes might be vary depending on whether the child has normal hearing or different degrees of hearing loss.

For more information about current studies, or to have your infant or child participate in future studies, please contact Dr. Nicholas Smith at 402-452-5070, smithn@boystown.org, or visit http://www.nicholasasmith.com.