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Child executive functions (cognitive flexibility, inhibitory control, working memory) are key to success in school. Cortisol, the primary stress hormone, is known to affect cognition; however, there is limited information about how child cortisol levels, parenting factors and child care context relate to executive functions in young children. The aim of this study was to examine relationships between child cortisol, parenting stress, parent coping, and daycare quality in relation to executive functions in children aged 3–5 years. We hypothesized that (1) poorer executive functioning would be related to higher child cortisol and higher parenting stress, and (2) positive daycare quality and positive parent coping style would buffer the effects of child cortisol and parenting stress on executive functions. A total of 101 children (53 girls, 48 boys, mean age 4.24 years ±0.74) with complete data on all measures were included. Three saliva samples to measure cortisol were collected at the child’s daycare/preschool in one morning. Parents completed the Behavior Rating Inventory of Executive Function – Preschool Version (BRIEF-P), Parenting Stress Index (PSI), and Ways of Coping Questionnaire (WCQ). The Early Childhood Environment Rating Scale – Revised (ECERS-R) was used to measure the quality of daycare. It was found that children with poorer executive functioning had higher levels of salivary cortisol, and their parents reported higher parenting stress. However, parent coping style and quality of daycare did not modulate these relationships. Identifying ways to promote child executive functioning is an important direction for improving school readiness.

No abstract

Recent evidence suggests that infants do not perceive all existing speech sounds from birth. For example, the velar and alveolar nasal place contrasts are so subtle that infants require experience to perceive it [e.g., Narayan et al. (2012)]. Here, we examine English-learning infants’ perception of another subtle contrast: pre-voicing on stop consonants. Six- and 10-month-olds’ ability to discriminate between voiced and voiceless stops (phonemically contrastive in English) as well as voiced and pre-voiced stops (allophonic in English, but contrastive in other languages such as Dutch) was tested using a variant of the stimulus alternation paradigm (SAPP). Six-month-olds (N = 34) distinguished between voiced and voiceless stops (p < 0.05), but not between voiced and pre-voiced stops. Ten-month-olds (N = 32) failed to discriminate either contrast. We conclude that (1) English pre-voicing may be a subtle contrast requiring experience to perceive, and (2) this version of the SAPP might not be an ideal methodology to examine discrimination abilities in 10-month-olds. Overall, our findings thus far fit well with the notion that some contrasts require experience to perceive, as well as with past studies reporting mixed results regarding English-learning infants’ ability to perceive pre-voicing contrasts [e.g., Aslin et al. (1981), Lasky et al. (1975)].