Dispositional mindfulness has been defined as a focused mental process achieved through intentionally focusing on aspects of the self and being non-judgmental while connecting to one’s present moment of experience. Dispositional mindfulness has been linked to mental health outcomes such as stress, emotion, rumination, and executive function. More information on the effectiveness of current mindfulness-based interventions may have indicated improved mental health outcomes owing to attentional control, emotional regulation, and heightened self-awareness. Designs of previous clinical studies have demonstrated an amelioration of psychiatric symptoms through exposure to mindfulness training. Furthermore, they have indicated that the effects of mindfulness training are noticeable, such as changing the structure and functions of the brain.Evidence for the benefits of dispositional mindfulness or mindfulness training has been illustrated in relation to theneurophysiological mechanisms underlying the brain.

Recently, imaging and neuroelectric studies targeting mindfulness conditions have been employed to investigate the potential neuroscience mechanisms associated with mindfulness. The accumulating evidence suggests that mindfulness is associated with brain activation and connectivity. The default mode network (DMN) is a relative new discovery among brain networks that provides a viewpoint useful for discussing operations of brain functions and networks. DMN helps us understand the individual processes of internal psychological states, cognition, the causes of mental diseases, and behavioral affected performance. The DMN is a set of brain regions including the medial prefrontal cortex (mPFC), posterior cingulate cortex (PCC), and precorneal cortices. These regions are those typically deactivated regions during cognitively demanding tasks. Conversely, the increase of activity among these brain regions reflects the individual’s mental states as mind wandering and experiencing thoughts unrelated to the current task. The available evidence indicates the important role of DMN in daily life. This is because of DMN involving self-referential mental activity and manifesting experience with prior recalls, associated with psychiatric diseases and negative mental states.

Specifically, few studies have explored the effects of mindfulness on the DMN. However, studies have yet to specify the characteristics of mindfulness training that benefit brain outcomes. This review investigates the manner in which neuroscience mechanisms of mindfulness are based on the perspectives of DMN to determine whether dispositional mindfulness or mindfulness training is consequential to the brain functions. The functional magnetic resonance imaging (fMRI) technology appears to be most suitable for observing functional connectivity in the DMN. Furthermore, electroencephalography (EEG) explores functional connectivity in the DMN and can complement the limitations of temporal resolution in an fMRI. Consequently, we focused on cross-sectional, longitudinal, and interventional empirical studies using an fMRI and an EEG to further understand the relation between mindfulness and mental health and their influence on brain mechanisms. The literature reviews were carried out in the following way: The first section briefly describes the definition of mindfulness and DMN, then introduces the recent trends of researchers. The second section reports cross-sectional, longitudinal, and interventional empirical studies. Finally, the third section summarizes information regarding the relations between mindfulness and DMN, explores the potential contributions of how mindfulness may apply to an educational context, and offers recommendations for future research directions.

We searched in the official home pages of the PubMed database using keyword search terms “mindfulness,” “meditation,” “default mode network,” “mind wandering,” “fMRI” or “EEG.” Titles and abstracts were selected for initial screening of articles for narrative review, whereas other studies on protocol that did not use fMRI and EEG were excluded. The previous studies on mindfulness have indicated that dispositional mindfulness levels are associated with mental health and alternations of brain structures or functions. Mindfulness training positively impacted mental health outcomes and ameliorated the symptoms of psychiatric diseases. Diseases such as depression and Alzheimer’s might be caused by inappropriate or aberrant activation of the DMN. This further leads to the internalizing of such disorders while negatively affecting mental health-related quality of life. Furthermore, fMRI studies have indicated the association between dispositional mindfulness or mindfulness training and decreased brain function activity. These include the ventromedial prefrontal cortex (vmPFC), dorsomedial prefrontal cortex (dmPFC), PCC, and anterior cingulate cortex (ACC) for functional connectivity in the DMN region as well as increased connections between the brain network relevant to executive control or attention and the limbic system. That is, functional connections between the hippocampus and amygdala positively influenced the emotional and cognitive processing of the individual. Thus, mindfulness-based interventions contributed to greater mental health. Few studies have used EEG measurements. EEG studies have revealed that dispositional mindfulness or mindfulness training was associated with DMN network activity in the gamma and theta frequency bands. Therefore, mindfulness is associated with reduced activation of DMN.

Collectively, the effectiveness of mindfulness for mental health is affected by changes in DMN, thereby improving normal functioning of the brain and behavioral performance. In addition, mindfulness training promotes the development of DMN core regions. Dispositional mindfulness or mindfulness training may promote moving away from mind wandering driven by DMN, thereby contributing to beneficial effects on brain functions. The current evidence thus may provide information about the potential benefits of mindfulness for people with mental health issues. Thus, meaningful mindfulness training could help individuals reset their habitually interfering or automatically distracting thoughts to become capable of keeping away from self-related ruminations and engaging in more focused awareness of the present moment. The research also proposed the potential effectiveness of mindfulness in child and adolescent development research in the field of education.

Although previous studies have indicated the roles of DMN in mindfulness and mental health, these findings must be interpreted cautiously because of conceptual and methodological issues (e.g., lower bounds on sample size, lack of active controls, limited use in measurements and methods) in recent research on mindfulness. Therefore, methodological challenges should be addressed to improve the research design. Overall, these reviews provide significant research development trends with regard to neuroscience studies on mindfulness and DMN. The evidence suggests the following research method improvements: using more rigid research designs that adopt randomized controlled trials while including adequate sample sizes and using active control groups; factoring sample generalizability that includes accumulated knowledge derived from these results, which then should be applied for investigating the emerging field of neuroscience of mindfulness in a variety of populations; measuring the effects of mindfulness training and their applications since the impact of mindfulness training will be enhanced if there are relative emphasis assessments given to different components; and improved reviews of the extant literature of mindfulness and mental health associated with DMN functional connectivity, which is still not well understood. Future studies should focus on the mediation effects of DMN on mindfulness and behavioral performance outcomes as well as DMN and its role in individual behavior performance. Importantly, current evidence remains limited due to few studies being applied to different populations. Accordingly, future research should clarify the unacknowledged effects of mindfulness training on DMN.