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


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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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The Blissful Brain: Neuroscience and proof of the power of meditation

Dr Shanida Nataraja


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Structure

  • General introduction

  • Bridging science and spirituality

  • Peering into the meditating brain

  • Health benefits of meditation


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Structure

  • General introduction

  • Bridging science and spirituality

  • Peering into the meditating brain

  • Health benefits of meditation


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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


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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


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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


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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


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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


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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


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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


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Cerebral Lobes


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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


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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)


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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


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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


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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


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Structure

  • General introduction

  • Bridging science and spirituality

  • Peering into the meditating brain

  • Health benefits of meditation


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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


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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


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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


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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


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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


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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


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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


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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


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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


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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


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Structure

  • General introduction

  • Bridging science and spirituality

  • Peering into the meditating brain

  • Health benefits of meditation


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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


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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


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Expanding or Restricting Attention


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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


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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


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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


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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


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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


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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


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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


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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


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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”


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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


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Simplified Meditation Process

Decrease in activity

Increase in activity


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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


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Simplified Meditation Process

Decrease in activity

1

1

2

1

Increase in activity

3


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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


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Simplified Meditation Process

Decrease in activity

Increase in activity


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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


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Simplified Meditation Process

Decrease in activity

5

1

2

1

Increase in activity

4

3


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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


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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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Different Brain Waves


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Wave Changes in Meditation

  • Early stages of meditation:

    • increase in alpha waves; state of relaxed alertness

    • decrease in beta waves; reduction in intrusive thoughts

  • During transcendental experiences: increase in theta waves; feelings of bliss

  • In deeper stages of meditation: some practitioners display high frequency beta or gamma waves; assembly of fragments of information into single, coordinated picture


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Maxwell Cade

  • Proposed (1978) that different levels of consciousness could be correlated with different brain wave patterns

  • Meditative pattern involves absence of the beta waves and an increase in alpha and theta wave

  • Can be differentiated from lower states of consciousness by presence of multiple frequency bands (i.e. alpha and theta) rather than just one


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Relaxation Response

  • Meditation superimposed on general relaxation response

  • Mediated by parasympathetic nervous system, this includes

    • decrease in oxygen consumption

    • reduction in the elimination of carbon dioxide

    • a reduction in heart rate, respiratory rate, blood pressure, and lactate levels in the blood, muscle tone, and blood cortisone levels

    • increase in the blood flow to the internal organs

    • increase in the temperature of the fingers

    • increase in skin resistance


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Facilitating Relaxation

  • Four different elements that facilitate the relaxation response during meditation

    • A mental device: shifts mind from logical and externally orientated, left-brained thinking to intuitive and internally orientated, right-brained thinking

    • A passive attitude: rating or judging the session can cause anxiety

    • A comfortable position: minimal muscular effort required to maintain an upright position without promoting sleep

    • Quiet environment: minimizes noises that may distract the practitioner or make them anxious


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Variable EEG Signatures

  • Not possible to give one EEG signature relevant to all types of meditation or all individuals

  • Precise changes in the EEG recording differ depending on meditative technique used

  • Fundamental differences between different techniques are reflected in different EEG signatures


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Structure

  • General introduction

  • Bridging science and spirituality

  • Peering into the meditating brain

  • Health benefits of meditation


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Psychosomatic Disorders

  • Psychosomatic disorders (i.e. those that involve physical symptoms, but have an emotional or psychological origin)

  • Psoriasis, eczema, stomach ulcers, high blood pressure, and heart disease have all be shown to be triggered and exacerbated by psychological factors, such as stress and anxiety

  • In the West, the prevalence of psychosomatic diseases continues to increase in line with stress in our social environment


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Neuroendocrine System


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Neuroendocrine System

  • Stress can trigger long-term abnormalities in the neuroendocrine system

  • Individual is in state of permanent arousal; high cortisol levels

  • Stress can

    • impair memory and damage hippocampus (as in Cushing’s syndrome)

    • cause both depression and anxiety

    • compromise the immune system


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Health Benefits of Meditation

  • Physiological effects of meditation differ

    • from one individual to the next

    • depending on the specific meditative technique used

  • Meditation has been associated with a number of important physical and mental health benefits

  • The size of benefit increases with more frequent meditative practice, and are most pronounced in experienced meditators


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Frequently Cited Criticisms

  • Few studies use the same rigorous methods routinely used in studies of investigational pharmaceuticals

  • Studies have produced highly variable, and often conflicting results


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Highly Variable Findings

  • It is difficult to accurately assess adherence to meditation program; it is impossible to provide participants a “fixed dose” of meditation

  • Meditation is an expansive term; it is therefore not valid to compare the findings of studies using different techniques

  • Subject differ psychologically, emotionally, and spiritually; it is therefore impossible to enrol a homogenous population

  • A specific meditative technique is not “for everyone”


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Mindfulness-Based Stress Reduction

  • Technique first proposed by Jon Kabat-Zinn and his colleagues in 1979

  • Possible therapeutic option for patients suffering from physical, psychosomatic, and psychiatric disorders

  • Although taught independently of any religious or esoteric tradition, it is rooted in contemplative spiritual traditions

  • Trains practitioner to develop enhanced awareness of the moment-to-moment experience of emergent mental processes


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Meditation and Stress

  • Meditation

    • decreases cortisol levels in healthy subjects and patients with cancer

    • lowers activity in the sympathetic system

    • reduces lipid peroxide content of the blood

    • reduces coronary prone behaviour


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MBSR and Stress

  • MBSR investigated in a wide range of patients (pain, cancer, heart disease, depression, and anxiety)

  • Overall, studies indicate MBSR is effective method of stress reduction associated with benefits in terms of

    • overall health and

    • the ability of these patients to cope with their condition


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MBSR and Stress

  • Carlson et al: improved overall QoL, stress symptoms, and sleep quality in breast and prostate cancer outpatients

  • Shapiro et al: reduced anxiety and psychological distress, including depression in med students

  • Roth et al: decreases need for primary care consultations

  • Kabat-Zinn et al: improves clearance of skin lesions in patients with psoriasis


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Meditation and the GSR

  • Effects of meditation on arousal system can be detected as changes in the Galvanized Skin Response (GSR)

  • Measure of skin resistance related to cortical arousal

    • High arousal = decreased resistance and GSR

    • Low arousal = increased resistance and GSR

  • Meditation triggers increase in GSR that stabilizes in 5–10 min; mean increase was 17.5% in one study of 50 meditators


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Meditation and Immune System

  • Cortisol suppresses immune system

  • Meditation

    • Davidson et al: boosts immune response to a vaccine

    • Solberg et al: reduces immune response to stress

    • Antoni et al: increases immune activity after 10 weeks in patients with HIV; the result of meditation on reducing stress levels and depression


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Subjective Psychological Effects

  • Boost in energy levels

  • Increased self-acceptance

  • Release from tendency to self-blame

  • Increased acceptance of others

  • Increase ability to express emotions, both positive and negative

  • Less prone to bouts of irritability, impatience, and emotional or behavioural outbursts

  • Improved and expanded sense of identity


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Meditation and Anxiety

  • Meditators tend to be slightly more neurotic and anxious than the general population

  • Long-term meditators less anxious than novice meditators and non-meditators

  • Novice meditators show significant decreases in anxiety after training

  • Meditators also report reduce levels of neuroticism; reduction is related to frequency of meditative practice


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Meditation and Addiction

  • Meditation plays important role in treatment of addictive behaviour

  • Meditation reduces alcohol and nicotine consumption and use of illegal substances, tranquillizers, prescribed medications, and even caffeine

  • These reductions

    • suggest decreased reliance on external means of altering the physical and mental state

    • reflects reduction in attention given to the intrusive thoughts that elicits desire to consume addictive substance


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Meditation and Coping Strategies

  • Promising supportive intervention for patients who need to learn coping mechanisms for chronic pain

  • Mindfulness of movement produced improvements in symptoms in patients with multiple sclerosis

  • Reduces psychological distress in patients with variety of chronic physical or psychosomatic disorders, including chronic fibromyalgia


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Possible Adverse Effects of Meditation

  • Shapiro et al: possible adverse effects of meditation in 27 long-term meditators

  • About 2/3 of subjects reported at least one adverse effect, including

    • relaxation-induced anxiety and panic

    • decreased motivation

    • confusion and disorientation

    • Depression and feeling “spaced out”

  • The positive effects of meditation outweighed the negative effects


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Increasing Awareness of Unconscious Behaviour

  • Galvanized Skin Response (GSR)

  • Psychophysiological response measured in skin containing sweat glands

  • GSR can be

    • visualised as a moving trace on a computer monitor

    • translated into an auditory tone

    • encoded in changes in the frequency of a flashing light or indeed the colour of that light

    • combined with computer gaming wizardry to allow the subject to play a video game


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Interpreting the GSR

  • High level of arousal is indicated by a fall in skin resistance (and a drop in the GSR reading)

  • Low level of arousal or relaxation is reflected in an increase in skin resistance (and a rise in the GSR reading)

  • Neural processes remain undefined, but sympathetic nervous system is involved; opening of sweat glands in a state of “fight or flight” leads to fall in skin resistance, and thus drop in GSR meter reading


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GSR Trace


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Biofeedback and the ACC

  • The anterior cingulate cortex (ACC) is a small structure tucked in between the hemispheres

  • The ACC

    • is involved in decision-making and evaluating “how well things are going” after we make a particular decision

    • becomes activated during biofeedback

    • is intimately related to the sympathetic arousal system, playing a role in the intentional modulation of bodily arousal


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Using Biofeedback

  • Primary interest has revolved around its ability to increase an individual’s awareness of unconscious, automated behaviour

  • Often individuals are unaware that they are in a constant state of arousal

  • Constant state of arousal gives rise to elevated stress levels, and thus a wide range of different stress-related diseases


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Visualizing Physiological Changes

  • Individual can visualise physiological changes occurring to different stimuli, both external and internal

  • By visualising the effects of these stimuli on the level of arousal, the individual becomes consciously aware of these physiological responses

  • Conscious awareness of these responses permits the individual to bring arousal under voluntary control


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How Does it Work?

  • The GSR displays information about physiological processes as a visual cue

  • The practitioner uses this cue to keep their arousal at a steady level and to change it at will

  • The individual learns to modify their behaviour to elicit a pre-defined goal

  • Control over the biofeedback instrument translates into control over arousal

  • With time, the individual can control arousal without the need for the visual cue


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Using the GSR in Meditation

  • Relaxation plays an important role in the preparatory stages of meditation

  • Practice should begin with

    • a gradual and progression relaxation of the muscles of the body

    • an unforced and progressive quietening of the mind

  • Both physical and psychological elements lead to a reduction in arousal

  • The effects of different strategies on arousal can be quantified and compared


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Using the GSR in Meditation

  • By recording arousal during meditation, the individual can examine how changes to arousal correlate with their subjective experiences

  • The GSR recording can also be examined by the meditator’s guide who can then offer the practitioner additional feedback


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