Corbett, Maria L.

Previous research has shown that the intrapersonal characteristics (e.g.,
temperament) of children are associated closely with alterations in the functioning of the
hypothalamic-pituitary–adrenal (HPA) stress axis. However, consistently capturing direct
associations between these characteristics and stress reactivity of the HPA axis has, at
times, yielded disparate findings. Thus, using the Rothbart model of temperament
(Rothbart & Derryberry, 1981) as a guide, the main goal of this project was to investigate
and identify intrapersonal characteristics that moderate associations between other
intrapersonal characteristics of the child and stress reactivity during development (e.g.,
trait by trait interactions). Additionally, study variables were assessed for meaningful
associations and, on average differences between those who responded to the stressor
paradigm and those who did not. A sample of 45 male and 37 female students (n=82, M=
9.66 yrs.) from six, fourth and fifth grade classes partook in a mathematically based stressor paradigm administered in the classroom. Salivary cortisol and behavior measures
were collected in two waves over a 7-week period. Several significant results emerged.
Overall, children who responded to the stressor paradigm had significantly higher levels
of traits associated with a more inhibited behavioral style. Further, several meaningful
interactions surfaced in which intrapersonal characteristics of various categories,
including reactive, regulatory, and ambiguous, interacted with one another to predict
stress reactivity. Of note, the majority of the interactions involved self-regulation and
surgency. These two intrapersonal characteristics interacted with several others, helping
to elucidate the unique influences of these intrapersonal characteristics on each other and,
subsequently, stress reactivity of the HPA axis. These results illustrate that interactions
between multiple intrapersonal characteristics should be taken into consideration in the
future when studying the relationships between intrapersonal characteristics and stress
reactivity of the HPA axis.

The current study utilized a quasi-experimental nonequivalent groups design to investigate whether a 5-week long Mindfulness Meditation Intervention (MMI), would impact measures of attention, positive and negative affect, state and test anxiety, mindfulness, and reactive cortisol levels in 107 school aged children. A series of reliability corrected ANCOVAs were performed on all behavioral variables. Results indicated that those in the MMI group did not differ from their cohorts on any of the behavioral measures. Reactive levels of salivary cortisol were also collected and assayed in a subsample of 25 participants. An ANCOVA on cortisol change scores was performed and findings did not reach statistical significance. Post-hoc power analyses revealed that this could be due to inadequate sample size. To conclude studies utilizing a MMI of longer duration or with larger sample sizes may be required in assessing the usefulness of MMIs in behavioral and physiological measures in non-clinical child populations.