1. Introduction
The ability to regulate emotion develops across the first two decades of life, corresponding with maturational changes in brain networks supporting emotion processing and self-regulation.1Emotion regulation is central to developmental outcomes.2–4 Deficits in emotion regulation can increase risk of mental disorders in adulthood (e.g., depression5). Therefore, strategies that are effective for bolstering emotion regulation during childhood may have long term benefits, such as ameliorating adverse outcomes during adulthood.6 Emotion regulation strategies that involve forms of mindfulness and meditation originate from ancient practices.7 Meditation refers to an umbrella of mental practices that involve the monitoring and regulation of attention and emotion.8,9 Mindfulness is a form of meditation that involves focusing attention to and accepting thoughts and emotions in the present.10 There are also individual differences in the tendency towards mindfulness (i.e., trait mindfulness) that can change over time through deliberate meditation practice.11 Meditation techniques are now integrated into established treatments for psychological disorders involving emotion dysregulation, including depression.12Meditation programs have been shown to be effective for reducing stress, anxiety, depression, and pain among clinical13 and non-clinical14 adult populations. They show promise for reducing disease- and treatment-related distress among patients with chronic conditions, such as cancer.15 Active engagement in meditation has also been shown to lower self-reported pain and negative emotion.16,17
Although most research has been conducted in adults, emerging evidence suggests that mindfulness and meditation are beneficial for children. A meta-analysis of 33 randomized controlled trials reported benefits of meditation programs on attention, depression, and stress among clinical and non-clinical pediatric samples.18 Mindfulness and meditation-based programs are popular in school settings,19 and increasingly used to help children cope with stressful experiences, such as chronic conditions (e.g., cancer)20,21 or trauma.22 Meditation as an emotion regulation strategy is promising for preventing mental disorders, given that nearly half of all mental disorders begin during childhood and adolescence.23 However, the neural mechanisms supporting meditation as an emotion regulation strategy in children remain unclear. Insight on these mechanisms could help validate and improve interventions for at-risk pediatric populations exposed to high stress and trauma.
Meditation strategies are distinct from other forms of emotion regulation, such as distraction. Rather than controlling attention away from emotional experiences, meditation strategies involve noticing and accepting emotional reactions as they arise.8Meditation also appears to be neurobiologically distinct from other forms of emotion regulation that rely on ‘top down’ modulation of emotional responses. More ‘cognitive’ forms of emotion regulation, such as distraction, commonly engage brain regions in the central executive network (CEN), with core nodes in the dorsolateral prefrontal cortex and the parietal cortex.24,25 Meditation emotion regulation strategies do not appear to engage the CEN. Rather, these techniques have been shown to reduce activation in regions of the default mode network (DMN), including the medial frontal cortex (MFC), posterior cingulate cortex, and precuneus, during deliberate meditation and exposure to aversive stimuli.16,17,26 The DMN is associated with self-referential thought and depressive rumination.27,28 Prior research suggests that depressed individuals fail to downregulate DMN activity when exposed to negative emotional stimuli.29 Taken together, existing research suggests that meditation can modulate DMN activity, and these effects do not rely on ‘top-down’ control mechanisms. This is important because children might not be able to employ complex regulatory strategies due to underdevelopment of the CEN.30,31Further, simple meditation strategies, such as focused attention to the breath, may be more accessible to children in stressful situations.
To our knowledge, only two functional magnetic resonance imaging (fMRI) studies have examined the neural correlates of meditation training in children. These studies report lower amygdala response to fearful faces and lower resting-state functional connectivity between the DMN and CEN in children (mean age = 11.75 years) following an 8-week mindfulness-based school program relative to a control program.32,33 These finding support the notion that meditation can modulate brain activity (e.g., DMN) in children. These patterns are consistent with our prior fMRI study showing that more trait mindful youth spent less time in a dynamic functional connectivity state characterized by higher DMN-CEN connectivity.34However, no studies to our knowledge have examined neural activity in children actively engaged in meditation emotion regulation.
To address this gap, we examined the within-subjects effects of meditation on brain activity in a sample of children with cancer, who experience significant disease and treatment-related distress.35 Participants received minimal meditation training (4 hrs) through a well-established martial arts-based meditation program21,36 prior to undergoing an adapted version of an established fMRI emotion regulation task in the scanner. We compared two meditation emotion regulation techniques (i.e., focused attention and mindful acceptance) with a control condition (i.e., passive viewing) and with a non-meditation emotion technique (i.e., distraction). Participants were asked to engage in one of the four conditions while they were exposed to aversive video clips (e.g., a child receiving an injection), and rated their negative emotion after each trial. This design allowed us to test (1) whether meditation techniques can reduce brain activity in the DMN, and (2) whether meditation emotion regulation techniques are more effective than a non-meditation technique —distraction — at reducing DMN activity. We also (3) compared brain activation during the two meditation techniques, based on evidence that different meditation techniques have different effects on brain activity.37