Saihariharan Nedunchezhian – The Role of Parenting Stress in Influencing the Development of Inhibitory Control in 36- and 48-Month Old Infants

During the summer of 2018, I worked in Dr. Stacy Drury’s Behavioral and Neurodevelopmental Genetics Laboratory (BANGL), whose lab focuses on the transgenerational impact of maternal adverse childhood experiences (ACEs) on infant health. As part of this project, I was conducting research experiment on a task related to executive functioning. Executive functioning (EF) includes a vast array of cognitive tasks that is predominantly regulated by the prefrontal cortex (PFC), an area associated with regulation of affective responses and attentional networks. Of all these various tasks, delay of gratification tasks measure inhibitory control by challenging a child to selectively inhibit an immediate reward to obtain a larger future award. Inhibitory control, a component of EF, is the regulation and suppression of specific tasks to achieve a later or more accurate outcome and there is evidence that the early parent-child relationship can also influence inhibitory control development. In addition to studying inhibitory control, I also aimed to study the parenting stress, as measured by the Parenting Stress Index (PSI), to analyze for maternal competence, attachment, health and role restriction as well as the infant’s distractability, adaptability, demandingness, temperament, and acceptability. Through studying infant behavior in the marshmallow task, the data for which is collected in the 36 and 48 month visits, and the scores on the PSI, I expected to research if early maternal parenting stress predicted child inhibitory control, does early maternal warmth predict inhibitory control, and whether the interaction between parenting stress and maternal warmth affects child inhibitory control development, particularly at 3 and 4 years of age.

I began the summer by fine tuning the coding scheme and finishing its standardization so data can be abstracted from the marshmallow visits that existed for 36 and 48 month visits. However, there were delays with accomplishing this task as proper protocol was not followed to establish interrater reliability. Therefore, to ensure proper compliance, the interrater reliability was once again established and the preliminary data from that was used as starting point for data abstraction for the project. I worked the summer to finish abstracting the data from the [missing text]. The data was then merged with the existing longitudinal data set to permit direct testing of my hypotheses. In addition, I began preliminary research to understand the standardization of PSI as a reliable measure for parenting stress and to understand which subscales correlated with inhibitory control development. However, by the end of this summer, I had to take a leave of absence from the lab to focus on my mental and physical health.

During my summer project, I learned some irrefutable truths about research. Progress in research is measured by one’ ability to learn constantly, to be organized, and to communicate clearly and effectively. With regards to organizational component, I learned that it is extremely important to document every step taken as it will help with troubleshooting errors made in research. I also learned that, with high intercoder reliability, the results abstracted would be attributable to the subject’s performance, thus providing valid results for the study. Achieving high reliability will help other researchers using this protocol to attain similar data, which can then be used by the lab to answer other research questions on the role of maternal experiences in infant neurobiological development of inhibitory control. These findings could also be used clinically to inform mothers how they can help with their child’s development. From this project, I learned that by conducting research in a stepwise manner and having a clear understanding of the organizational components, the tangible research goals that I can achieve will motivate me to keep researching on the importance of maternal health on proper infant development.

Written by Saihariharan Nedunchezhian, Ching Grant recipient, 2017-2018