Abstract
Recent calls for mindfulness measures beyond self-report abound, especially for children. Because breath awareness is central to many mindfulness practices, the breath counting task has been proposed as a behavioral measure of mindfulness for adults. In the current study, we investigated whether the breath counting task can also serve as a valid behavioral measure of children's mindfulness. We examined psychometric properties across breath counting, three established mindfulness questionnaires, and a behavioral cognitive control measure in a sample of 109 children ages 9-13 years. We also offered 1-2 weeks of audio-based mindfulness training to a subset of children (n = 67) who completed daily breathing exercises, then reassessed their breath counting and self-reported mindfulness. In the full sample, children's breath counting showed psychometric properties and patterns similar to those of adults, was positively associated with overall cognitive control performance, but was unrelated to their self-reported mindfulness (p's > 0.24). However, breath counting did improve following training amongst the subset of children who completed 1-2 weeks of daily mindfulness exercises (p < 0.001, η (2) = 0.23), whereas self-reported mindfulness did not (p = 0.44). Our findings suggest that the breath counting task captures aspects of mindfulness separate from those measured by children's self-reports, and may be more sensitive to training impacts. We recommend the use of both self-report and behavioral measures of mindfulness, like the breath counting task, in future work.