1) Default Mode Network / Monkey Mind
 
Default Mode Network is what your brain "defaults" to when you aren't doing any specific "task" with it (which is called the Task Positive Network).
Tools for the investigations of the brain with tools such as:
  • Functional Magnetic Resonance Imaging (fMRI)
  • Positron emission tomography (PET)
  • Electroencephalography (EEG) is an electrophysiological monitoring method to record electrical activity of the brain. It is typically noninvasive, with the electrodes placed along the scalp, although invasive electrodes are sometimes used in specific applications. EEG measures voltage fluctuations resulting from ionic current within the neurons of the brain
  • Blood-oxygen level-dependent (BOLD) fMRI technology
  • Arterial spin labeling (ASL) perfusion
  • Single Proton Emission Computed Tomography (SPECT), which involves an IV injection of radioactive tracer at the “critical” moment. The tracer is specific for certain tissues and goes to, and remains there, until later scanning gives a 3-D image.

The best paper was done by Andrews-Hannah, et. al @ Harvard which was published in Neuron in 2010. This paper found 11 different "selfing" centers that constitute most of the DMN activity. They found that these 11 centers were divided into two "core" centers, and two "subnetworks" which the core communicates heavily with.


​​Sagittal MRI slice with highlighting indicating location of the posterior cingulate.
The "core centers" are those shown in yellow; the two subnetworks are shown in blue and green:
  • The two core centers, the Posterior Cingulate Cortex (PCC) and the medial PreFrontal Cortex (mPFC) are in yellow.
  • The blue subnetwork is involved in "self and other", i.e you and your chair, you and your computer, you and your partner, etc.
  • The green subnetwork is responsible for "you in time", i.e. you in the future, you in the past, etc.
If there is no "tasking", the DMN is active, and the core network is functioning and whatever other subnetwork is required, perhaps both.





​​MRI scan showing regions of the default mode network
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​Default mode network connectivity. This image shows main regions of the default mode network (yellow) and connectivity between the regions color-coded by structural traversing direction (xyz -> rgb).
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​The DMN is widely-accepted as producing selfing/I-ing, "self-in-time" and "self-and-other".  If either of the two (yellow) core centers, the posterior cingulate cortex/PCC and amPFC, are deactivated, then the whole network deactivates, selfing stops, and "All is One" and "now, now, now" manifest.
​For most folk, their DMN is a randomly wandering self-narrative, of I, me, my thoughts. That self-narrative of "I/me/my" thoughts is what causes most of our (imagined) problems, fears, craving, suffering and unhappiness.
 
we have found in the on-going Yale study that experienced meditators can permanently change their DMN to one that does not have the randomly wandering self-narrative, as mine has done, to one of stillness.
 
The thickness of the lines between centers indicates how often their activity is correlated, and presumably connected. If the core PCC for example, is deactivated, then presumably both subsidiary networks would be shut down.


​​Novice Meditator rt-fMRI
Blue - PCC deactivated
Red - PCC activated






​"Gary" rt-fMRI
Blue - PCC deactivated
Red - PCC activated    
The DMN typically is activated when folk are not doing a task.  Deenergizing the DMN with either long-term meditation or with psychedelics (esp. psilocybin) has been demonstrated in studies in leading journals to produce the classical mystical experiences of "all is One" and living "now, now, now".
 
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