Infant and Child Development

  • Upper Extremity Strength and Dexterity in Children

    The purpose of this study is to better understand the function of patients who experience problems with their arms and hands. These problems can have many different causes such as birth deformities, medical conditions, or different types of injuries or disorders. We will collect data from participants with and without these problems.

    You may be eligible if you:

    • Have a history of deficits in upper extremity function due to an etiology (Patient Group).
    • You are healthy with no history of upper extremity injury or disorders (Control Group).

    If you agree to participate, we will ask you to come to CHLA for one test session that lasts 1-2 hours. We will take measurements of your hands and arms, like the size of your hand and your hand function. We will also ask you to squeeze and hold a spring in your hand.

    For more information, contact:
    Nicole Greaves
    Study Contact Person
    nmueske@chla.usc.edu

    HS protocol # CCI-11-00045
    Grant #: NIH Grant AR050520, 84-133E2008-8
    Sponsor: National Institute of Health, National Institute on Disability and Rehabilitation Research

    Kick Start: Learning to Move the World

    We are using an infant mobile to shape the amount and the coordination of infant kicking in the earliest months of life. The infants learn that their leg actions can activate the movement and music in the mobile. The “contingency” that is learned is fundamental in development as infants learn that their actions have consequences on the world around them.

    The purpose of this study is to determine the ability of 3-month old full-term and preterm infants to: (1) learn the contingency between leg action and mobile activation, and (2) demonstrate a greater amount kicking and an increase of selective leg movement when leg actions are reinforced with mobile activation. Each infant participates in 2 sessions of mobile reinforcement on consecutive days. Day 1 consists of a 2-min non-reinforcement condition (spontaneous kicking) followed by a 6-min reinforcement condition (the infant mobile rotated and played music). Day 2 consists of a 2-minute non-reinforcement condition, 6-minute reinforcement condition, and 2-minute non-reinforcement condition.

    For more information, contact:
    Linda Fetters, PhD, PT, FAPTA
    Director of the Developmental Motor Performance Laboratory
    (323) 442-1022
    fetters@usc.edu  

    Modeling the Infant Exploratory Process

    A critical issue in the study of infant development is to identify the processes by which task-specific action emerges from spontaneous movement. It has been proposed that infants learn to tune their spontaneous movements to generate task-specific action through reward learning, which is characterized by exploration preceding learning, and accompanied by task specific reduction in variability. However, the contribution of exploration to the early learning of task-specific action has little empirical evidence during infancy. We are computationally modeling our infant kicking data to predict the movements associated with learning the task. The difference between the model and the task-specific movement trajectory data from each infant is considered to be the exploration related variance. Our findings will provide the first quantification of the contribution of exploration to the early learning of task-specific leg action of infants.

    For more information, contact:
    Linda Fetters, PhD, PT, FAPTA
    Director of the Developmental Motor Performance Laboratory
    (323) 442-1022
    fetters@usc.edu  

    The Emergence of Movement Dynamics in Selective Infant Leg Action

    The purpose of this study is to investigate the biomechanical factors that contribute to the early emergence of selective leg action. We define selective leg action as the coordination between intralimb leg joints that allows increased degrees of freedom among joints. We compare dynamics between a 2D and 3D computation of torques and the dynamics that emerge longitudinally as infants mature in the first months of life.

    For more information, contact:
    Linda Fetters, PhD, PT, FAPTA
    Director of the Developmental Motor Performance Laboratory
    (323) 442-1022
    fetters@usc.edu

    Using Movement to Measure Early Brain Development

    What: Infant participants needed for research study
    Who: Infants with typical development and infants at risk for developmental delay, 1 to 6 months of age, who are not yet reaching and grasping objects
    When: monthly testing

    We want to learn:
    How infant brain activity and movement patterns change as they learn to reach for objects.

    Procedures:
    In your home: We will measure your infant’s weight, length and developmental milestones. We will place small movement sensors on your infant’s arms using comfortable, custom-made arm sleeves. Your infant will wear the sleeves the rest of the day to measure how many arm movements he or she makes in a day. You will remove the sleeves at bedtime.

    In your home or in our laboratory (per your preference): We will place small movement sensors on your infant’s arms and trunk. We will place a special cap on your infant’s head. The cap only records brain activity through the skull and hair, it does not do anything. We will record brain activity and movement patterns as your infant looks at and/or reaches for toys.

    Follow Up: We will call or email you to find out about your infants development at 2 years of age.

    You will receive:

    • payment each day of testing
    • souvenir photos
    • your infant’s weight, length and developmental milestone measurements

    Contact: Beth A. Smith, PT, PhD at: beth.smith@usc.edu or (323) 442-4072 University of Southern California Division of Biokinesiology and Physical Therapy. IRB # HS-14-00690