Functional MRI brain scans can distinguish the advanced meditation state known as Jhana (ACAM-J) from ordinary consciousness with modest accuracy. Using regional homogeneity (ReHo) maps from 20 advanced meditators, machine learning classifiers reached 66.82% accuracy. The prefrontal and anterior cingulate brain regions were most important for the classification, consistent with their roles in attention and metacognition. The results suggest that machine learning can feasibly classify advanced meditation states, supporting future work on neuromodulation and mechanistic models of such states.
Non-invasive brain stimulation (NIBS) can help researchers investigate the neural mechanisms underlying meditation's beneficial effects on well-being and consciousness. Prior research has mainly targeted frontal and parietal cortices, suggesting NIBS might boost meditation's behavioral and neural effects. NIBS has also revealed distinct neural signatures in long-term meditators. However, methodological variations across studies make definitive interpretation of results challenging. Future work should focus on core substrates of meditation, including specific brain networks and oscillations, and causal mechanisms of advanced meditation. Overall, NIBS-meditation research holds promise for enhancing meditation-based interventions in both non-clinical and clinical populations.
About 45% of people from three international communities—UK online panelists, US-based MTurk workers, and readers of a rationalist blog—report having had at least one sudden unusual mental or somatic experience, not caused by drugs, that is often interpreted as spiritual or mystical. The most common experiences include derealization (17%), unitive experiences (15%), and ecstatic thrills (15%). Following such experiences, respondents reported a mix of positive and negative well-being outcomes; 13% reported moderate or greater suffering and 1.1% reported life-threatening suffering. Of those who suffered, 63% did not seek help. These emergent phenomena appear widespread and can lead to both benefits and harms that are not adequately addressed by clinical practice.
In both novice and experienced meditators, decreased activity in the posterior cingulate cortex (PCC) corresponded with the subjective experience of effortless awareness during meditation. Participants could volitionally control the PCC signal in the direction associated with that state. Novice meditators achieved the target state a median of 77.97% of the time, and experienced meditators a median of 89.83% of the time. Median confidence ratings linking PCC activity to effortless awareness were 8 out of 10 for novices and 9 for experienced meditators. The findings suggest EEG neurofeedback from the PCC could serve as a tool for meditation training.