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The Blissful Brain: Neuroscience and proof of the power of meditation Dr Shanida Nataraja

The Blissful Brain: Neuroscience and proof of the power of meditation Dr Shanida Nataraja. Structure . General introduction Bridging science and spirituality Peering into the meditating brain Health benefits of meditation. Structure . General introduction

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The Blissful Brain: Neuroscience and proof of the power of meditation Dr Shanida Nataraja

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  1. The Blissful Brain: Neuroscience and proof of the power of meditation Dr Shanida Nataraja

  2. Structure • General introduction • Bridging science and spirituality • Peering into the meditating brain • Health benefits of meditation

  3. Structure • General introduction • Bridging science and spirituality • Peering into the meditating brain • Health benefits of meditation

  4. The Human Brain • First mentioned in Edwin Smith Surgical Papyrus 1700 BC • Largely disregarded by the Egyptians • Aristotle proposed brain was cooling unit to lower blood temperature

  5. Site of Human Intellect • Importance first noted by Hippocrates in 5th Century BC • Supported by Galen of Pergamum: dissections and surgeries on Roman gladiators • Confirmed by Thomas Willis (1621-1673): founding father of modern brain science

  6. The Brain as a Black Box • The brain efficiently controls behavior so we can run on “auto-pilot” • The brain possesses astounding and unrivalled range of abilities • The brain • weighs about 1 ½ bags of sugar • has the consistency of blancmange • contains 100 billion neurons • is highly interconnected

  7. A Dynamic Network • Each neuron is miniature processing unit • receiving information from other cells • processing information • relaying resulting data to other cells • Every person has unique configuration • Precise wiring of all the connections in the brain is continually changing, adapting with experience

  8. Brain Complexity • When examined under microscope, brain tissue appears as tangled mess • Closer examination reveals it to be highly ordered • Cells with similar structure and function arranged in layers with common orientation

  9. Hierarchal Structure of Brain • Hindbrain, midbrain, and forebrain • Newer brain regions laid on top of older regions • Older useful circuitry incorporated into newer, more advanced circuitry

  10. The Cerebral Cortex • Particularly predominant in humans • Highly folded external appearance • Mediate all of the cognitive skills associated with being human • Can be divided into four lobes: frontal; temporal; parietal; and occipital

  11. Cerebral Lobes

  12. Left Brain vs. Right Brain • Both hemisphere have similar functions with respect to sensory processing and motor function • In other respects, the function of the two hemispheres is asymmetrical • The left hemisphere is associated with analytical, rational, and logical processing • The right hemisphere is associated with abstract thought, nonverbal awareness, visual–spatial perception, and emotions

  13. Reality or Fantasy? • Right hemisphere: • more realistic impression of particular sensory experience • intuitively examines experience and stores it as images and emotions • Left hemisphere: • filters and rationally analyses the experience • stores it as a mental map • influenced by the individual’s experiences in the past (i.e. their conditioning)

  14. Thalamus and the Senses • Gateway for sensory information flowing into cortex • Where sensations are first consciously experienced • Important role in attention • Gateway for motor information flowing into cortex • Important role in motor intention

  15. Hypothalamus • Maintains constant internal environment • Modulates emotional responses with other limbic structures • Regulates arousal through action on autonomic nervous system Hypothalamus Pituitary Gland Autonomic NervousSystem

  16. Autonomic Nervous System • Sympathetic (“fight or flight” responses): increases heart rate and breathing rate; slows digestion; dilates pupils • Parasympathetic (“rest and digest” responses) nervous systems: decreases heart rate and breathing rate; stimulates digestion

  17. Structure • General introduction • Bridging science and spirituality • Peering into the meditating brain • Health benefits of meditation

  18. Religion versus Science • Assumed that reality could be given a single, complete, and unambiguous description in human language • Neither Science nor Religion alone can provide a complete description

  19. Science and Spirituality • 1997 survey of US scientists revealed 40% believed in a personal God • Quantum pioneers, including Einstein and Bohr, have been described as mystics • Importance of the integration of scientific and spiritual knowledge • Complementary aspects of a greater whole, each capturing a differing and partial representation of a greater reality

  20. Neurotheology • Patients with temporal lobe epilepsy • Have hallucinations with a religious content • Have seizure-induced feelings of religious ecstasy • Report spontaneous religious conversions • There is even evidence that some mystics may have had temporal lobe epilepsy

  21. The “God Module” • Ramachandran (1997) proposed that the temporal lobe played an important role in mystical and religious experiences • Media and scientists alike declared that “God module” had been found in the human brain

  22. Persinger’s Helmet • Persinger proposes mystical experiences are result of microseizures in the deep structures of the temporal lobe • These are provoked by personal life crises and near-death experiences • An individual’s susceptibility to these microseizures depends on excitability of the temporal lobe • Healthy individuals, as well as epileptic patients, can also display these microseizures

  23. Transcranial Magnetic Stimulation • Subjects stimulated by a weak magnetic field over the right hemisphere • Using a specially designed helmet of magnets • 80% of subjects reported the sense of a presence

  24. Artefacts of Brain Function • Persinger proposed “religion is a property of the brain, only the brain, and has little to do with what’s out there” • Taken as proof that God doesn’t exist; God and all religious thought are artefacts of brain function • Inherent limitations of scientific method ensure that we will never be able to definitively prove or disprove the existence of God

  25. Mystically Hard-Wired • Stimulation of certain areas of the brain to evoke certain experiences is not best way of investigating these experiences • These artificial experiences can rightly be viewed as being artefacts of brain function • The artificial stimulation experiments merely reinforce belief that humans are hard-wired to be receptive to mystical or religious experiences

  26. Subjectivity • Humankind has created a rigid conceptual map of our World that • acts as a framework to communicate details of our experiences to others • limits our ability to describe and understand our experiences • This mental map is • formed by the cumulative experience of a person’s lifetime • an imprint of all of our personal, societal, and cultural conditioning

  27. Conceptual Map • Our conceptual map • Defines our goals and expectations • Dictates the way in which we perceive the world and our relationship to it • Provides an explanation for our experiences • Everyone’s conceptual map is slightly different

  28. Structure • General introduction • Bridging science and spirituality • Peering into the meditating brain • Health benefits of meditation

  29. Definition of Meditation • Countless different meditative techniques • Meditation • involves a specific technique that is both clearly defined and taught to the practitioner • involves, at some stage, progressive muscle relaxation • involves, at some stage, a reduction in logical processing • is self-induced • involves a skill, referred to as an anchor, that allows the practitioner to effectively focus their attention

  30. Types of Meditation • Can be passive and active • Passive meditation • empties mind of thought and is attentive on entire experience, usually by using an anchor, such as the breath • involves a widening of attention and includes techniques such as mindfulness • Active meditation • focuses attention on a specific mantra or image • involves a narrowing of attention and includes techniques such as TM and Zen meditation

  31. Expanding or Restricting Attention

  32. Newberg and d’Aquili • Observed meditators in controlled conditions • Release of a radioactive tracer into the blood system triggered by meditator pulling on string • SPECT (single photon emission computed tomography): blood flow in different regions of the brain can be visualized

  33. Transcendental Experiences • Associated with specific patterns of brain activity, in specific regions of the cerebral cortex • Key features • Increase in activity in frontal cortex: attention • Decrease in activity in parietal cortex: dissolving of self/non-self boundary

  34. Frontal Cortex: Attention • Meditation begins with the intent to practice followed by a re-focusing of the attention • The intention of the practitioner to sit “meditate” triggers thalamus to re-focus the the attention either inwards or outwards • Focused attention acts to “clear the mind” through redundancy • Reflected in increase in activity in frontal cortex

  35. Parietal Cortex: Orientation • Meditative practice associated with dissolving of self/non-self boundary • Meditation involves decrease in activity in region of brain that constructs our self/non-self boundary, in both the left and right hemisphere • This decrease can partially explain the expansion of awareness that can be experienced during meditation

  36. Shift From Left to Right Brain • Effect on self/non-self boundary can also be understood in terms of initial shift in meditation from left to right brain activity • Left brain: ego-centered thinking • Right brain: holistic, non-ego thinking • Attention is a right brain function; focused attention thus involves shift from left to right brained thinking

  37. Passive Meditation • Practitioner begins with intent to clear mind of thoughts • Then attention is focused on gap between thoughts or on the breath • Attention • triggers shift to right brained activity • makes practitioner less aware of redundant sensory information and thoughts

  38. Switch From Left to Right • Fundamental to the shift in thinking that accompanies contemplative practice • It also underlies the power of myths • All myths have a common framework • Existential question is posed: e.g. “How was the Universe created” • The issue raised is presented in terms of conflict between two apparently irreconcilable opposites: e.g. good–evil, life–death • A possible resolution is presented, usually in terms of the reconciliation of polar opposites

  39. Myths and Brain Function • The first stage triggers activity in the left hemisphere; comprehension of language and the comparison of concepts are left-brained activities • The second stage triggers activity in the right hemisphere; comprehension of unity and reconciliation of polar opposites requires right-brained activity • The progression from first to second stage involves a switch between left- and right-brained thinking

  40. A Quest for Meaning • Activity in the left hemisphere drives activity in the right hemisphere • The quest for meaning to our experiences triggers a shift in brain function that allows us to perceive the “big picture”

  41. Passive Meditation • Practitioner thus becomes less aware of their orientation in the spatial dimensions and in time • Decrease sense of orientation is reflected in decreased activity in parietal lobe that leads to • a sense of no or infinite space and/or time • an inability to convey the experience efficiently through language

  42. Simplified Meditation Process Decrease in activity Increase in activity

  43. Activation of Limbic System • Activation of hippocampus • confers emotional value to experience • triggers the autonomic nervous system • Maximal activation of autonomic nervous system lead to • a blissful, peaceful state via parasympathetic system • and then a mentally clear and alert state via sympathetic system

  44. Simplified Meditation Process Decrease in activity 1 1 2 1 Increase in activity 3

  45. Active Meditation • Practitioner begins with intent to clear mind of thoughts • Then attention is focused on single object, image, or mantra • Attention filters out redundant sensory information and thoughts • Activity in occipital and frontal lobes fixes object in practitioner’s mind

  46. Simplified Meditation Process Decrease in activity Increase in activity

  47. Active Meditation • Activation of hippocampus and autonomic nervous system • Peak response prompts hippocampus to dampen activity • This results in decrease in activity in parietal lobes and thus • sense of no or infinite space and/or time • a loss of the ability to comprehend the experience in rational terms • an inability to describe the experience using language

  48. Simplified Meditation Process Decrease in activity 5 1 2 1 Increase in activity 4 3

  49. Important Features • Crucial role of intention • Role of thalamus in re-focusing attention • Role of attention in “clearing the mind” • Shift from left to right brain activity through sustained attention • Dependence of self/non-self boundary on activity predominantly in left parietal cortex • Widening of awareness and holistic thinking stemming from right-brained activity • Impact of meditation on body through activation of the arousal/relaxation systems

  50. Electrical Brain Recordings • Electroencephalogram (EEG) is a non-invasive technique • Records combined electricity activity of large groups of neurons within the brain • In clinical practice, 19 electrodes are positioned on head

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