Undergraduate Honors Theses

Thesis Defended

Spring 2019

Document Type


Type of Thesis

Departmental Honors


Integrative Physiology

First Advisor

Monique LeBourgeois

Second Advisor

Alena Grabowski

Third Advisor

Lameese Akacem


Introduction: Poor sleep health in early childhood is known to negatively affect behavioral self-regulation, which is linked to reduced school readiness and poor later life outcomes. The aim of this study was to understand the role of sleep loss in behavioral self-regulation strategies and inhibitory control using a standard task (Forbidden Toy) that measures a child’s capacity to delay gratification. Compared to a day when toddlers had a daytime nap, it was hypothesized that after acute nap deprivation they would have a shorter latency to touching the toy and would resort to more immature, maladaptive self-regulation strategies to delay gratification.

Methods:In this experimental, counterbalanced study, 25 healthy children (11 males, 34.1 ± 2.3 months-old)followed an sleep stabilization schedule for ≥5 days prior to a baseline (nap) and one day of acute nap deprivation condition (no-nap). Inhibitory control was assessed using an age-appropriate, attractive toy. Children were left alone with the toy for a 3-minute waiting period and videotaped. The videos were coded for latency to touch and 11 discrete self-regulation strategies. McNemar repeated measures Chi-Squared tests were used to compare between conditions: 1) the number of children who touched the toy and 2) the number of children who employed each of the strategies. Paired t-tests (one-tailed) were used to compared the latencies to touch and the percentage of time each strategy was employed between conditions.

Results:There was no difference between the baseline and sleep restriction conditions in the number of children who touched the toy (X-squared= 0, p = 0.50) and or their mean latency to touch (t = 0.27, p = 0.393). Of the 11 strategies coded, no significant differences were found in the number of children who used each of the strategies or the percent time the children spent using each strategy: visual inspection (t = 0.35, p = 0.37); self-soothing (t = 0.62, p = 0.27); talk about task rules (t = -1.32, p = 0.10); irrelevant speech (t = -0.04, p = 0.49); unintelligible speech

(t = 0.16, p = 0.44); fidgeting (t = 0.38, p = 0.35); removing self (t = 1.03, p = 0.16); physical restraint (t = 1.64, p = 0.06); passive waiting (t = 0.80, p = 0.22); object distraction (t = -1.17, p = 0.13); and social bids (t = -0.03, p = 0.49).

Discussion:These findings indicate that acute nap deprivation in toddlerhood may not have an immediate impact on inhibitory control and self-regulation strategies. This is inconsistent with other findings reported in the field, and limitations in the task administration and contextual factors (e.g. socio-economic status) may contribute to the conflicting results. Through early childhood, there are striking developmental changes in behavior and control, and at 30-36 months of age, children may not have sufficient cognitive and emotional resources to exert inhibitory control and self-regulate. Future research should examine developmental changes in the effects of acute sleep restriction on inhibitory control and self-regulation strategies as children progress through the early childhood years.