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The role of neuroscience in building a CBS conceptualization of mindfulness. Lindsay Fletcher, M.A. June 22, 2010.
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The role of neuroscience in building a CBS conceptualization of mindfulness Lindsay Fletcher, M.A. June 22, 2010
One of the last remaining problems in science is the riddle of consciousness. The human brain—a mere lump of jelly inside your cranial vault—can contemplate the vastness of interstellar space and grapple with concepts such as zero and infinity. Even more remarkably it can ask disquieting questions about the meaning of its own existence. "Who am I" is arguably the most fundamental of all questions. - V.S. Ramachandran
The case of bird song • Baby birds learn to sing by hearing and then practicing • There are specific neural pathways that are necessary for song acquisition and production • Adult neurogenesis discovered in canaries • Does this mean that song learning takes place in the brain?
Definitions of Mindfulness Bishop et al. 2004: • “Self-regulation of attention so that it is maintained on immediate experience, thereby allowing for increased recognition of mental events in the present moment” and • “A particular orientation toward one’s experiences in the present moment, an orientation that is characterized by curiosity, openness, and acceptance.”
Definitions of Mindfulness Kabat-Zinn 1994: “Paying attention in a particular way: on purpose, in the present moment, and nonjudgmentally” DBT: “The intentional process of observing, describing, and participating in reality nonjudgmentally, in the moment, and with effectiveness”
Self-as-Content • A process whereby an individual experiences the self as defined by verbal descriptors and ongoing evaluation. • This persistent commentary creates a cohesive sense of self based on the “story” of who we are. • New and old information are filtered through this view of self in order to create a cohesive content-based story that reflects a verbal knowing of self that is based on continual evaluation and comparison.
The Default Mode Network • Corresponds with activity in mPFC and other midline regions • Tonic activity at rest • Abnormal activity in the DMN correlates with many psychological problems • Decreased activity in this network in experienced meditators (Brefczynski-Lewis et al., 2009)
Self-as-Context • The experience of self as an observer of thoughts, feelings, and bodily sensations as passing events occurring in the present moment rather than solid entities that define self. • Self-as-context transcends static conceptual verbal descriptors of self, such as “I am smart” or “I am lazy” • The perspective of I-Here-Now
Meditation and Self-as-Context • Meditative traditions refer to a transcendent self that is not separate from the rest of humanity • Non-separateness • Functional contextual approach = “one world”
Meditation and mPFC • Meditation results in increased cortical thickness in mPFC (and other areas) (Lazar et al. 2005) • Greater activity in mPFC in meditators practicing mindfulness of breathing than in non-meditators (Holzel et al. 2007)
A Hypothesis • Two pathways including mPFC correspond to different aspects of self? (Gusnard and Raichle 2001; • Schmitz and Johnson 2007) • Activity in a dorsal network corresponds to self-referential processing, both task-related and introspective • Activity in a ventral network corresponds the integration of sensory and motor information from the external and internal environments or orienting to salient sensory information that is determined to be self-relevant
Neural correlates of “narrative self-focus” and “experiential focus” investigated in meditators and non-meditators using fMRI • Only meditators displayed a neural signature that was different depending on the mode of self • These results may indicate that meditation trains the ability to shift from self-as-content to self-as-context Farb, N. A. S., Segal, Z. V., Mayberg, H., Bean, J., McKeon, D., Fatima, Z., et al. (2007). Attending to the present: Mindfulness meditation reveals distinct neural modes of self-reference. Social Cognitive and Affective Neuroscience, 2, 313–322.
The mPFC and Empathy • There is overlap in areas of mPFC that correspond to self-relevant tasks and tasks identifying the internal states of others • This may point to neural correlates of empathy and is consistent with our model if those areas involved also correlate to the observer self
There are some conflicting data about the role of mPFC and self processes • Data such as Farb et al 2007 add depth to a psychological analysis of the potent processes targeted during meditation that lead to beneficial effects • Neural correlates of self-as-context and self-as-content lend validity to how we parse these processes and that they are differentially impacted by meditation practices
Data such as these do not confirm that these processes are “real”, or that the effects of meditation are “real”, they simply provide additional support for our theories or may encourage us to adjust our theories • From a contextual perspective, the “self” cannot be found in the brain • The “answer” to suffering and key to psychological health do not exist in the brain, yet neuroscience can help our cause
There are some conflicting data about the role of mPFC and self processes • Perhaps more important than activity in specific areas is the “global dynamic cerebral state”