Neural bases of consciousness in Zen meditation: central executive and default mode networks during cognitive conflict.

Consciousness in Zen meditation has garnered considerable interest in psychology and neuroscience, particularly in relation to its association with enhanced self-awareness. Zen meditation fosters social harmony by addressing mental and social conflicts, linking individuals to various societal aspects through the practice. This meditation, rooted in Buddhism, aims to perceive thoughts without judgment by attentively focusing on the present. However, the neural mechanisms behind its benefits have remained elusive. To investigate, we used functional magnetic resonance imaging on two groups: Zen monks with extensive meditation experience (average 7.53 years) and a control group without meditation background. Both groups completed the Stroop cognitive conflict task followed by meditation. Zen meditation, when performed by skilled monks, improved responses and cognitive control, and reduced cognitive conflict in the lateral and medial prefrontal cortices compared to the control group. Conflict tasks are generally associated with increased activity in the central executive network (CEN), whereas activity in the medial prefrontal cortex, a core component of the default mode network (DMN), has been linked to internally oriented processes such as self-referential thought and mind-wandering. The involvement of the DMN during meditation, however, appears to depend on the specific meditation style and cognitive state, with prior studies reporting mixed findings. These networks are often considered to exhibit an antagonistic relationship, with task engagement typically accompanied by CEN activation and concurrent DMN suppression. However, Stroop conflict trials in the present study did not show a strong inverse relationship between DMN and CEN activity. Instead, connectivity analyses indicated suppression within DMN-related regions.