The Dec 2007 issue of *Social Cognitive and Affective Neuroscience* (vol. 2,
#4) includes a study: “Attending to the present: mindfulness meditation
reveals distinct neural modes of self-reference.”

The article is by Norman A. S. Farb, Zindel V. Segal, Helen Mayberg, Jim
Bean, Deborah McKeon, Zainab Fatima, & Adam K. Anderson.

Here’s the abstract: “It has long been theorised that there are two
temporally distinct forms of self-reference: extended self-reference
linking experiences across time, and momentary self-reference centred on
the present. To characterise these two aspects of awareness, we used
functional magnetic resonance imaging (fMRI) to examine monitoring of
enduring traits (‘narrative’ focus, NF) or momentary experience
(‘experiential’ focus, EF) in both novice participants and those having
attended an 8 week course in mindfulness meditation, a program that
trains individuals to develop focused attention on the present. In
novices, EF yielded focal reductions in self-referential cortical
midline regions (medial prefrontal cortex, mPFC) associated with NF. In
trained participants, EF resulted in more marked and pervasive
reductions in the mPFC, and increased engagement of a right lateralised
network, comprising the lateral PFC and viscerosomatic areas such as the
insula, secondary somatosensory cortex and inferior parietal lobule.
Functional connectivity analyses further demonstrated a strong coupling
between the right insula and the mPFC in novices that was uncoupled in
the mindfulness group. These results suggest a fundamental neural
dissociation between two distinct forms of self-awareness that are
habitually integrated but can be dissociated through attentional
training: the self across time and in the present moment.