A comprehensive study summarizing the scientific research on meditation is available free online from the Institute of Noetic Sciences. The publication (also for sale in book format) is titled “The Physical and Psychological Effects of Meditation” (1996) by Michael Murphy and Steven Donovan. In the helpful introduction Eugene Taylor discusses the historical roots of meditation, outlines meditation’s introduction to the modern West, and provides an overview of meditation as a subject of scientific study in the West, India, and China.

When it comes to defining meditation, Taylor writes:

As for modern developments, in trying to formulate a definition of meditation, a useful rule of thumb is to consider all meditative techniques to be culturally embedded. This means that any specific technique cannot be understood unless it is considered in the context of some particular spiritual tradition, situated in a specific historical time period, or codified in a specific text according to the philosophy of some particular individual.

Taylor is indicating that meditation doesn’t exist as we popularly conceive it — in an abstract or general form — only as distinct techniques which have emerged from specific philosophical and religious backgrounds. As an example, Taylor points out that the widespread and well-regarded Mindfulness-Based Stress Reduction (MBSR) program, founded at the University of Massachusetts Medical Center, “combines elements of Vipassana, a Theravada form of Buddhist meditation from Burma, and Zen practices from Japanese Buddhism with Hatha yoga, a tradition from the Indian subcontinent.” (An entry at TricycleBlog, the weblog of the Buddhist magazine Tricycle, offers some thoughts about the MBSR program’s secular presentation of Buddhist meditation.)

When meditation is put under the scientific microscope, Taylor refers to two points of confrontation. The first is whether a rationally-based scientific method can adequately evaluate the realm of ‘intuition and insight’:

Science, the product of Aristotelian thinking and the European rationalist enlightenment, now turns its attention to the intuitive transformation of personality through awakened consciousness (and other such Asian meanings of the term enlightenment). This means that the faculties of logic and sense perception, hallmarks of the scientific method, are now being trained on the personality correlates of intuition and insight, hallmarks of the traditional inward sciences of the East.

To grasp what meditation is has proven to be no easy task. The underlying and usually hidden philosophical assumptions of traditional, rationalist science do not value the intuitive. They do not acknowledge the reality of the transcendent or subscribe to the concept of higher states of consciousness, let alone, in the strictest sense, even admit to the possible existence of unconscious forces active in cognitive acts of perception.

Secondly, Taylor asks whether science itself will be transformed by the encounter:

The essential difficulty here is not just the reformulation of meditation techniques to fit the dictates of the scientific method, but rather what might be called a deeper, more subtle, and potentially more transformative clash of world epistemologies. It is not simply that meditation techniques have been difficult to measure but rather that, in the past, meditation has largely been an implicitly forbidden subject of scientific research. Now, however, major changes are currently underway within basic science that presage not only further evolution of the scientific method but also changes in the way science is viewed in modern culture. An unprecedented new era of interdisciplinary communication within the subfields of the natural sciences, a fundamental shift from physics to biology, and the cognitive neuroscience revolution have liberalized attitudes toward the study of meditation and related subjects. Meanwhile, the popular revolution in modern culture grounded in spirituality and consciousness is having a growing impact on traditional institutions such as medicine, religion, mental health, corporate management strategies, concepts of marriage, child rearing, and the family, and more. Increasingly, educated people want to know much more about meditation, while our traditional institutions of high culture remain unprepared as adequate interpreters.

The body of “The Physical and Psychological Effects of Meditation” is authored by Michael Murphy and Steven Donovan. Following their own overview of the scientific studies on meditation, they provide a detailed summation of the scientific research by organizing it into three categories: physiological effects, behavioral effects, and subjective reports. The research is then broken down by category as follows:

Physiological Effects

The Cardiovascular System
— Heart Rate
— Redistribution of Blood Flow
— Blood Pressure and Hypertension
— Other Cardiovascular Changes
The Cortical System
— EEG: Alpha Activity
— EEG: Theta Activity
— EEG: Beta Activity
— EEG: Hemispheric Synchronization
— EEG: Dehabituation
— Specific Cortical Control
— Other Cortical Changes
Blood Chemistry
— Adrenal Hormones
— Thyroid Hormones
— Total Protein
— Amino Acids and Phenylalanine
— Plasma Prolactin and Growth Hormone
— Lactate
— White Blood Cells
— Red Blood Cell Metabolism
— Cholesterol
The Metabolic and Respiratory Systems
Muscle Tension
Skin Resistance and Spontaneous GSR
Other Physiological Effects
— Brain Metabolism
— Salivary Changes
— Effectiveness in the Treatment of Disease
— Treatment of Cancer
— Changes in Body Temperature
— Alleviation of Pain
— Exceptional Body Control

Behavioral Effects

Perceptual and Cognitive Abilities

Perceptual Ability
— Reaction Time and Perceptual Motor Skill
— Deautomatization
— Field Independence
— Concentration and Attention
— Memory and Intelligence
Rorschach Shifts
Empathy
Regression in the Service of the Ego
Creativity and Self-Actualization
— Creativity
— Self-Actualization
Hypnotic Suggestibility
Anxiety
Psychotherapy and Addiction
— Psychiatry and Psychotherapy
— Addiction and Chemical Dependency
Sleep
Sex Role Identification

Subjective Reports

Equanimity
Detachment
Ineffability
Bliss
Energy and Excitement
Altered Body Image and Ego Boundaries
Hallucinations and Illusions
Dreams
Synesthesia
Extrasensory Experiences
Clearer Perception
Negative Experiences

Searchable Bibiliography

via Meditation Blog