Assessing the effects of engagement with maternal ostensive signals in infants with neurodevelopmental risk

• Main Author: Teo, Joan Wei Ling
• Other Authors: Victoria Leong
• Format: Thesis-Master by Research
• Language: English
• Published: Nanyang Technological University 2024
• Subjects: Social Sciences; Ostensive signals; Executive functions; Autism Spectrum Disorder (ASD); Preterm birth
• Online Access: https://hdl.handle.net/10356/181789
• Institution: Nanyang Technological University

Background. Social ostensive signals, such as gaze, gaze following, calling the infant’s name, gesture and smile, are communicative cues commonly observed during interactions between infants and caregivers to indicate intent to interact or convey information. While extensive research has documented how ostensive signals promote infants’ cognitive development specifically in learning, language and social skills, the effects of these signals on infants with atypical neurodevelopmental trajectories remains unclear. Furthermore, there is limited understanding on whether engaging in ostensive signals provides any indication of or contributes to the development of executive functions (EF) such as working memory, inhibitory control and cognitive flexibility. Research Questions. Therefore, this study aims to explore two main research questions regarding the roles of ostensive signals in early childhood. Firstly, the present study aims to characterise atypicality in processing ostensive signals, by studying differences between infants at risk of neurodevelopmental disorders and a typically developing cohort. Secondly, the study aims to understand how mother-infant ostensive signal exchanges influence the infant’s EF development and how that relationship differs between typically developing infants and familial risk of ASD infants. Methods. By observing mother-infant social engagement during a toy searching, Anot- B task (n=51), this study explores how ostensive signals may influence the development of EF in infants with varying neurodevelopmental risk. Specifically, the impact of ostensive signals on the following EF components (in an early emergent form) is examined: working memory (the ability to recall a hiding location), inhibitory control (the ability to resist reaching toward a previously rewarded location), and cognitive flexibility (the capacity to adapt to new rules or changes). Infants' performance was assessed through measures of reaction time and accuracy. Results. The findings indicate significant differences in the engagement of ostensive signals in preterm and ASD-at-risk infants with their mothers, as compared to typically developing infants. Additionally, the association between ostensive signals and emerging EF skills varied across infants with different neurodevelopmental risk. Typically developing infants who initiated more ostensive signals, also demonstrated shorter reaction times when making a correct response. However, preterm and ASD-at-risk infants had longer reaction times when they initiated more ostensive signals. Attending to maternal cues was associated with longer reaction time for the correct responses among typically developing and preterm infants. On the other hand, ASD-at-risk infants showed shorter reaction times when they responded to more maternal cues, especially mother’s gesture. Significance Statement. These findings suggest that engagement with ostensive signals has nuanced effects on performance in EF tasks in infants. While these signals can positively