By John M. de Castro, Ph.D.
“The nature of brain vs. mind vs. consciousness is a question that may remain unanswerable but the important thing to remember is to live in awareness of how interconnected each of these aspects of yourself really are. Using these tips, you will grow in self-awareness and strengthen your connections with the deepest parts of your consciousness.” – Operation-Meditation
We spend a tremendous amount of our time with our minds wandering and not on the task or the environment at hand. We daydream, plan for the future, review the past, ruminate on our failures, exalt in our successes. In fact, we spend almost half of our waking hours off task with our mind wandering. You’d think that if we spend so much time doing this it must be enjoyable. But, in fact research has shown that when our mind is wandering we are actually unhappy compared to when we are paying attention to what is at hand.
A system of the brain known as the Default Mode Network (DMN) becomes active during wind wandering and relatively quiet during focused on task behavior. It is involved when we are engaged in internally focused tasks such as recalling deeply personal memories, daydreaming, sleeping, imagining the future and trying to take the perspective of others. The DMN involves neural structures including the medial prefrontal cortex, anterior and posterior cingulate cortices, precuneus, inferior parietal cortex, and lateral temporal cortex. These areas of the DMN are functionally connected, such that they are simultaneously active during mind wandering.
Meditation is known to reduce the size and activity of the Default Mode Network (DMN) through a process known as neuroplasticity where the size and connectivity of neural structures are modified by experience. In today’s Research News article “Temporal Dynamics of the Default Mode Network Characterize Meditation-Induced Alterations in Consciousness.” See:
or see summary below or view the full text of the study at:
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4956663/
Panda and colleagues further investigate the effects of meditation on the DMN. They recruited male experienced meditators with over 20 years of daily meditation experience and a matched group of non-meditators. They then simultaneously measured brain activity with both functional Magnetic Resonance Imaging (f-MRI) and with electroencephalography (EEG) both while the participants were at rest and during meditation.
They found that the meditators in comparison to the non-meditators had reduced connectivity of the posterior cingulate cortex that was further reduced during meditation. The posterior cingulate cortex is a key structure of the DMN. This suggests that meditation reduces the ability of the DMN to produce mind wandering. They also found increased connectivity in the middle frontal and middle temporal gyri that increased further during meditation. These are both structures associated with focused attention. These effects suggest that meditation experience increases the activity of the attentional system while decreasing the activity of the mind wandering system.
Panda and colleagues analyzed the electroencephalography (EEG) signals recorded simultaneously with the functional Magnetic Resonance Imaging (f-MRI) characterizing periods of stable activity over brief periods of time called microstates. They found that meditators had these stable states more often and for longer periods of time both at rest and during meditation. The more years of meditation practice the greater the increased stability in the DMN. With the non-meditators these stable states in the DMN occurred more frequently and for longer periods during meditation. These findings suggest that meditation increases stability of the DMN and extensive meditation experience permanently alters the DMN to be more stable all of the time.
These findings suggest that meditation reduced the activity of the Default Mode Network (DMN) briefly during meditation or permanently with experience with meditation. This further suggests that meditation experience permanently alters the tendency for the mind to wander both during meditation and also at rest. The studies of the alterations of the nervous system with meditation suggest that the changes in the states of consciousness seen with meditation are reflected in changes in the underlying neural systems, producing great focus and less mind wandering.
So, permanently improve brain dynamics with meditation practice.
“we do know that meditation is a tool that can change brain activity to bring it closer to this optimal, high-performance brain wave pattern. Subjective experiences of meditators with this optimal brain wave pattern reveal that they experience bliss in this state.” – Shanida Nataraja
CMCS – Center for Mindfulness and Contemplative Studies
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Study Summary
Panda, R., Bharath, R. D., Upadhyay, N., Mangalore, S., Chennu, S., & Rao, S. L. (2016). Temporal Dynamics of the Default Mode Network Characterize Meditation-Induced Alterations in Consciousness. Frontiers in Human Neuroscience, 10, 372. http://doi.org/10.3389/fnhum.2016.00372
Abstract
Current research suggests that human consciousness is associated with complex, synchronous interactions between multiple cortical networks. In particular, the default mode network (DMN) of the resting brain is thought to be altered by changes in consciousness, including the meditative state. However, it remains unclear how meditation alters the fast and ever-changing dynamics of brain activity within this network. Here we addressed this question using simultaneous electroencephalography (EEG) and functional magnetic resonance imaging (fMRI) to compare the spatial extents and temporal dynamics of the DMN during rest and meditation. Using fMRI, we identified key reductions in the posterior cingulate hub of the DMN, along with increases in right frontal and left temporal areas, in experienced meditators during rest and during meditation, in comparison to healthy controls (HCs). We employed the simultaneously recorded EEG data to identify the topographical microstate corresponding to activation of the DMN. Analysis of the temporal dynamics of this microstate revealed that the average duration and frequency of occurrence of DMN microstate was higher in meditators compared to HCs. Both these temporal parameters increased during meditation, reflecting the state effect of meditation. In particular, we found that the alteration in the duration of the DMN microstate when meditators entered the meditative state correlated negatively with their years of meditation experience. This reflected a trait effect of meditation, highlighting its role in producing durable changes in temporal dynamics of the DMN. Taken together, these findings shed new light on short and long-term consequences of meditation practice on this key brain network.