The objectives of this project were to systematically review the impact of mother–infant interaction on the development of infants 12 months or younger and determine factors that mediate this relationship and early development. We systematically reviewed the literature and identified 21 papers which fulfilled inclusion and exclusion criteria. The majority of the studies found significant association between mother–infant interaction and language, cognition, motor, and social development during the first year of life. Only seven studies assessed motor development and four studies found significant relationship between motor development and mother–infant interaction. Prematurity, infant age, multiples births, maternal anxiety, maternal opioid exposure, history of foster care, and criminal record were the only factors found to mediate the relationship between mother–infant interaction and social, cognitive, and language development. The quality of the interactions between a mother and infant can both positively and negatively influence cognitive, language, and social outcomes during the first year of life. Additional research is needed to determine the influence of mother–infant interaction on motor development. Future research is needed on the efficacy of interventions designed to alter mother–infant interaction with the ultimate goal of achieving positive developmental outcomes during the first year of life.

While therapy services may start in the Neonatal Intensive Care Unit (NICU) there is often a gap in therapy after discharge. Supporting Play Exploration and Early Development Intervention (SPEEDI) supports parents, helping them build capacity to provide developmentally supportive opportunities starting in the NICU and continuing at home. The purpose of this single blinded randomized pilot clinical trial was to evaluate the initial efficacy of SPEEDI to improve early reaching and exploratory problem solving behaviors. Fourteen infants born very preterm or with neonatal brain injury were randomly assigned to SPEEDI or Usual Care. The SPEEDI group participated in 5 collaborative parent, therapist, and infant interventions sessions in the NICU (Phase 1) and 5 at home (Phase 2). Parents provided daily opportunities designed to support the infants emerging motor control and exploratory behaviors. Primary outcome measures were assessed at the end of the intervention, 1 and 3 months after the intervention ended. Reaching was assessed with the infant supported in an infant chair using four 30 s trials. The Early Problem Solving Indicator was used to evaluate the frequency of behaviors during standardized play based assessment. Effect sizes are including for secondary outcomes including the Test of Infant Motor Performance and Bayley Scales of Infant and Toddler Development. No group differences were found in the duration of toy contact. There was a significant group effect on (F1,8 = 4.04, p = 0.08) early exploratory problem-solving behaviors with infants in the SPEEDI group demonstrating greater exploration with effect sizes of 1.3, 0.6, and 0.9 at the end of the intervention, 1 and 3 months post-intervention. While further research is needed, this initial efficacy study showed promising results for the ability of SPEEDI to impact early problem solving behaviors at the end of intervention and at least 3 months after the intervention is over. While reaching did not show group differences, a ceiling effect may have contributed to this finding. This single blinded pilot RCT was registered prior to subject enrollment on 5/27/14 at ClinicalTrials.Gov with number NCT02153736.

Variability is commonly considered a key to typical motor development. However, multiple definitions and quantification systems have limited the clinical interpretation of variability and the translation of developmental research to assessment and intervention. The purposes of this perspective article are to highlight the importance of statistical variability and complexity in postural control during development and to describe implications for assessment and intervention during infancy and early childhood. Five tenets are proposed describing the role of variability in postural control to support movement experiences, exploration, and global development. Evidence for assessment and intervention focused on variability in postural control are introduced.