4.1 Limitations
Our sample consisted of a relatively small sample size of children with
cancer and results may reflect the unique neurobiology of this
population. We used a within-subjects design and multi-echo fMRI imaging
techniques to increase study power. Sampling limitations are attributed
to the low base rate of childhood cancer, which precluded our ability to
examine sex differences in neural or behavioral measures. However, the
sample size in the present study (n = 12) is consistent with
previously published neuroimaging studies in pediatric cancer survivors
(e.g., n = 8, 15).55,56 We focused on children
with cancer because this pediatric population is exposed to disease- and
treatment-related stress, is at increased risk of emotion
dysregulation,35 and because martial arts-based
meditation programs have shown to be effective for reducing pain and
emotional distress in this population.21,36 In
addition, the relatively wide age span (5-17 years) is a limitation due
to differences in functional connectivity in young children compared to
older teenagers. Another limitation is that we examined two forms of
meditation (i.e., focused attention, mindful acceptance) and one
cognitive emotion regulation strategy (distraction), which may not be
representative of all available emotion regulation techniques. In
addition, we did not have a non-distressing (e.g., positively-valenced)
condition to compare our activation patterns to, so it is unclear if the
resulting neural activation patterns are specific to regulation of
negative stimuli. Additionally, all participants had at least four hours
of meditation instruction. Findings may differ based on meditation
experience,17 as these techniques become more
automatized. Therefore, future studies should examine different forms of
meditation and the impact of meditation experience.