Neuroscience and Karma: Prologue II - The Brain

0. The Enchanted Loom

The BRAIN'S commanding presence orders sensation, movement, thought and a lifetime of memory. The central nervous system, a maze of nerve fibres, links all areas of the body to cells in the fabric of the brain, as in a loom.

Within that "enchanted loom" romanticized the Nobel prize winning physiologist Sir Charles Sherrington, "millions of flashing shuttles weave a dissolving pattern, always a meaningful pattern, though never an abiding one". Twenty-five centuries ago, Hippocrates, legendary father of medicine, declared "Not only our pleasure, om joy and our laughter but also our sorrow, pain, grief and tears arise from the brain; with it we think and understand, see and hear, and we discriminate between the ugly and the beautiful, between what is pleasant and what is unpleasant and between good and evil". In the sixth century B.C., Greek philosophers thought that the brain served as the organ of the mind and as the temple of the soul.

Object of mystery and superstition through most of history, human brain has revealed itself only in recent centuries. Modern technology enables neuroscientists to examine brain tissue for clues to nerve-regeneration and sprouting of neural fibres. Brain-surgeon Roger Sperry concludes that "the Brain's consciousness encompassed and transcended its physical workings; in the human head, there are forces within forces within forces, as in no other cubic half-foot of the universe that we know." Through the eyes of science, let us have a glimpse of the working of the enchanted loom.

BRAINSCAPE - THE PORTRAIT OF THE BRAIN

1. Divisions and Parts of the Brain

Through the centuries, surveyors of the brain charted every cerebral hill and valley. They sprinkled Latin names across the brainscape - amygdala, corpus callosum, hippocampus etc. Some divided the brain into three sections - forebrain, midbrain and hindbrain. They determined that the skull housed not one brain but two - a matched pair - the two hemispheres which communicate through the corpus callosum deep within the cerebral divide. Though symmetrical, the hemispheres are not necessarily equal. In most persons, the left brain dominates the right side of the body, accounting for right-handedness.

At its base, juts the brainstem where nerve pathways shuttle life's impulses between brain and body. It contains the medulla oblongata with reflex-centres which control heart-beat, blood pressure and breathing, and flash signals to swallow, sneeze and laugh. It is the most vital part of the entire brain, the evolutionary core, the primitive site for survival.

Guarding the rear of the medulla is the reticular formation, the brain's alarm apparatus, monitoring the sensory signals that pass through it, and alerting the decision-making cortex to take action. From the medulla and adjacent areas radiate the twelve pairs of cranial nerves which serve the sensory and motor needs of head, neck, chest and abdomen.

The bridge - the pons - serves as a neuronal link between cerebral cortex and cerebellum, the fore and the hind-brains; nearby is the control centre that regulates breathing rhythm. Wedged between stem and cerebral hemispheres, the cerebellum governs a human's every movement. Apparently initiating nothing itself, the cerebellum monitors impulses from motor centres in the brain and from nerve endings in muscles. Modifying and coordinating commands, it smoothes a dancer's footwork or lets a hand glide a glass to lips without sloshing the contents. There is evidence that it may also play a role in a person's emotional development modulating sensations of pleasure and anger.

Filling the ventricular lakes and their tributaries, the brain's precious cerebrospinal fluid measures less than half a pint and is renewed about three times a day. It supplies nutrients to and carries away metabolic wastes from the brain.

Wondrous alchemy is produced in the hypothalamus which lies just beyond the midbrain-end. It synthesizes hormones to control growth, raise and lower temperature, regulate the body's water-balance and activate sexual behaviour. The hormones funnel into the pituitary gland below, where they are stored or released into the blood-stream. Nearby is the pineal gland - the vestige of a primitive third eye - in fact, a light activated biological clock that regulates sex-gland activity.

The thalamus, at the top of the brainstem helps to regulate consciousness. Information from nearly every area of the body is relayed by it to the cerebrum above. The limbic system, composed of various parts, is the emotional brain.

Above spreads the vaulted cerebrum, the two-thirds of the brain where human thought and creativity originate. Hundreds of millions of microscopic threads of white matter form an array of connections between the cortex's nerve centres and distant parts of the brain. The corpus caliosum knits together the two hemispheres and unites the special powers of both hemispheres, one specializing in analytical and verbal skills, the other adept in space and pattern perception. The left one which dealt in the abstract symbols of language and numbers, was logical and sequential in processing information. The right one generated mental images, grasped things as a whole, was holistic and simultaneous in its thinking. Recent studies have established that the brain divided (by cutting the corpus caliosum) can function as ably as the brain intact.

Less than a 1/4 inch thick, the cerebral cortex^[1] forms a fissured mold snug against the skull. It is composed of six layers of cells meshed in some ten thousand miles of connecting fibres per cubic inch. Each hemisphere is further divided into four lobes:

1. Frontal lobe
2. Parietal lobe
3. Occipital lobe
   and
4. Temporal lobe.

Every voluntary movement from hand-shake to the wink of an eye is controlled by motor cortex in the frontal lobe. Sensory cells that respond to touch, heat, cold, pain and body-position cluster the parietal lobe. Visual cortex occupies a n area in occipital lobe at the back o each hemisphere. Hearing is processed in temporal lobe. In spanning parts of all lobes dwell the mysteries of thought, language and memory. Language control areas in left hemisphere, direct the smooth transfer of thought and expression into speech. But linguistic functions may be assumed by other areas including those in the right hemisphere, dormant until compelling need awakens lazy neurons. Prefrontal cortex (rather vaguely charted) is the realm of planning and foresight.

2. Important Parts and Functions

After this brief survey of the brainscape, let us have a closer look at some more important parts and functions of the brain.

A. Reflex Action

Some sensory messages require such a rapid response that they never even reach the brain. Touching a hot iron, for example, can trigger a protective circuit known as a reflex arc. When the hand touches the iron, receptor cells in the skin pick up the message and transmit it to sensory neurons which relay it directly to a motor neuron in the spinal cord. The motor nerve speeds a message back to the muscles of the arm and hand which yank the fingers away. The finger has already left the iron by the time the burn is felt. In due course, the brain, overriding lesser sensations, 'will trigger the muscular responses of frown and cry of pain.

B. Reticular Activating System

Roughly the size of a little finger, the reticular formation lies in the central core of the brainstem. It runs from the top of the spinal cord into the middle of the brain.

The ability to concentrate at a most critical moment, say at the match-point, in a tennis match, lies in the reticular formation. It operates continuously in all humans during periods of alert wakefulness.

Every second, 100 million messages bombard the brain carrying information from the body's senses. A few hundred, at most, are permitted through to brain regions above the brainstem. Of these, the conscious mind heeds a few. While a person may be partially aware of many sounds, smells or movements around him, concentration is limited to one sensation at a time. Without the reticular formation's alerting action, the cortex could not sort the significant messages from the trivial ones. The reticular formation continuously sifts and selects, forwarding only the essential, the unusual, the dangerous to the conscious mind.

Messages are sent as nerve impulses from sensory receptors in all parts of the body to the cortex through pathways that run up the spinal cord to the reticular formation. From there they are relayed to other brain regions. These pathways and the reticular formation are collectively called the reticular activating system - "RAS" for short. When stimulation of the reticular formation slackens, we sleep. Injury causes a coma, a prolonged state of unconsciousness. Reticular formation is, in essence, the physical basis of consciousness. Without this alarm apparatus, a person would be "reduced to a helpless, senseless paralyzed blob of protoplasm".^[2]

C. The Feeling Brain - Limbic System

Our passions and our drives are as much the brain's creations as are intellect and reason. The forces of fear, elation, grief, anger and lustarise from the most primitive region of the brain known as the limbic system.

The limbic system works with both the cerebrum above and the brainstem below. While connections of the limbic system with the cerebrum permit an interplay between reason and emotion, those with the brainstem help in maintaining a state of emotional balance and alertness. Generally, both of them work in harmony, but the balance can be easily upset. A highly activated limbic system can overwhelm rational thought, making a person speechless with fury or joy. Through conscious control, a person can resist the urge to eat or drink, fight back tears or suppress sexual desire.

Various parts of the limbic system encircle the brainstem, and nerve pathways, interwoven through these parts, send a continuous flow of electrochemical impulses that direct human drives and emotions. The hippocampus constantly checks information relayed to the brain by the senses and compares it to experience; the thalamus analyses and passes information from sensory and motor nerves to the brain. From hypothalamus arise feelings of pain, pleasure, punishment and rage. Above the hypothalamus is the amygdala, thought to be related to feelings of rage and aggression. The septum appears to contain yet another limbic pleasure centre.

D. The Hypothalamus

Only the size of a thumb-tip, a cluster of nerve cells, called the hypothalamus, receives one of the richest blood supply in the entire body. It nestles between the thalamus above and the brainstem below. Through its connection with the brainstem, hypothalamus maintains homeostasis, the body's internal equilibrium. It keeps body temperature constant at roughly 98.6 degrees F. Hunger, and thirst-censes in it serve as the body's appestat. Hypothalamic disorders may cause compulsive eating or loss of interest in food, with this sophisticated sensing system, the body constantly balances and replenishes itself. The hypothalamus controls growth and sexual behaviour through the pea-sized pituitary gland. When sensors detect a drop in hormones in the blood stream it commands the pituitary to step up production and the latter responds by organizing the endocrine glands' release into the blood. It is a delicate system of reciprocity. So crucial is it that injury to certain hypothalamic regions can kill the sex urge entirely.

The hypothalamus also coordinates the "fight or flight" reaction in times of emergency. It organizes a chain reaction of defenses with a single aim: to put the body in top physical condition to cope with the emergency. Under the command of the pituitary gland, adrenals spew out adrenalin And noradrenalin, the heart beats faster, blood pressure and blood sugar rises to supply maximum energy and the breathing becomes faster.

E. Centres of Pain and Pleasure - E S B

Much of our knowledge stems from electric stimulation of the brain or ESB. It was discovered that stimulation of different parts of limbic system provoked reactions ranging from anger and anxiety to euphoria, sexual interest and states of deep relaxation. For instance, while stimulation of a certain part of amygdala, above the hypothalamus, can incite fury, current applied only three millimetres away produced extreme relaxation and detachment. Cancer victims have received instant pain relief from septal stimulation.

Nobel Prize-winning Swiss physiologist, Walter Hess devised a method for penetrating deep brain structures. He stimulated thousands of brain-sites, most of them in the hypothalamus. Depending on the part stimulated, the cat, under observation, would eat, drink, curl up and sleep or become sexually aroused. He firmly believed that the true emotion could be electrically induced. Other scientists have confirmed his theory.

Reward- or pleasure-centres situated in the hypothalamus were accidentally discovered by psychologist James Olds and were later confirmed by further studies.

Transistorized radio receivers, activating cranial electrodes allowed stimulation by remote control which freed test animals from cables that had restricted their natural movements in experiments. Yale University physiologist Jose* Delgado transformed a charging bull into a docile animal by pressing a transmitter button sending radio signals through the electrodes implanted in two different parts of the limbic system.

F. Wonderful Chemistry of the Brain

In recent years, researchers have discovered nearly thirty chemicals that act as neurotransmitters, each designed to convey a different type of information. But the most exciting discoveries have led scientists to believe that the brain possesses a special chemical control system to cope with pain and stress by producing natural pain killers similar to morphine. They are called enkephalin meaning "in the head" and endorphine meaning the "morphine inside".

Enkephalins may also regulate mood. These chemicals, when heavily concentrated in the limbic system, act as the body's own 'natural high' and counteract disappointment, prevent depression, and produce euphoria.

Scientists, believe that further research into the body's natural opiates may lead to the development of non-addictive pain-killers and ultimately, to a total understanding of the complex chemistry of pain.

3. Brain and Consciousness

The desire to experience transcendence from ordinary consciousness is probably innate. Altered states of consciousness can be achieved

1. by taking perception-distorting (psychedelic) drugs and
2. through various techniques of meditation.

Practice of Meditation

All techniques of meditation share certain features: In quiet surroundings, the meditator concentrates on a single point of focus - a word, shape, idea, question or, perhaps, his own breathing. Such concentrated attention compels the mind to shift from its customary active state to one of passive receptiveness. As the mind's activity is stilled, the meditator becomes detached from thought. Some practitioners seek relaxation and a sense of well-being. Others, particularly those who practice a religion in which meditation plays a central role, aspire to mystical states.

Scientific findings showed reductions in blood pressure, heart-rate and oxygen-consumption, intensified alpha brain-waves and other signs of deep relaxation. The meditators produce a unique consciousness, a state of deep, though wakeful, relaxation. This "relaxation response", is the reverse of the 'fight-or-flight' reaction that causes blood pressure, hearth rate and oxygen consumption to soar during stress.

Similar feats of mind over body have been credited to the hypnotic trance. Hypnotic suggestions can bring about changes in heart-rate, stop bleeding, increase muscular strength, or lower one's sensitivity to pain. Hypnosis has cured phobias and caused warts to disappear spontaneously. Researches suggest that self-hypnosis or auto-suggestion allows practitioner to gain control over heartbeat, breathing, digestion and glandular activity - involuntary processes not normally subject to conscious control. Like meditation, it couples physical relaxation with mental concentration.

Self-hypnosis has been used as a psychoanalytic device to delve into the unconscious. Medical and psychiatric associations have approved its practice, and dental and medical schools now teach it.

A newer technique for consciously regulating physical processes is biofeedback. Sophisticated electronic equipment monitors a persons' brain-waves, blood pressure and other involuntary activities, displaying information, or feedback, about them. The biofeedback subject learns to control these activities through passive concentration, a relaxed mental state allowing the mind to respond to the audiovisual display and modify the particular physical process. It seems relaxation, rather than conscious effort, is the key to successful biofeedback.

4. Brain in Health and Disease

A. Advances in Neuroscience / CAT Scanner

In research in diagnosis and treatment, the neurosciences arc advancing with unprecedented speed. Before the advent of the brain scanner, in the early 1970's, many brain-disorders were difficult or impossible to detect by conventional X-ray techniques because these could not distinguish between a tumor and a healthy tissue, both being nearly the same density. The development of computerized axial tomography or CAT scanner has revolutionized the diagnosis of brain disorders. Doctors can now see into the deepest recesses and layer after layer of their patients' brains. The scanner's high speed computer projects a sharply focused, highly detailed tomogram, or cross section, of the patient's brain on to a television screen. A suspected tumor, blood clot or hemorrhage can be diagnosed quickly and accurately. The CAT scanner not only finds and determines the size of the tumor but a series of scans can distinguish a spreading from a non-spreading tumor and between old and new strokes.

B. Beyond CAT - NMR or MRI

A new method of scanning promises to take the place of CAT in the near future. Nuclear magnetic resonance imaging, shortened to NMR or MRI, is the technique in question. The single proton in the atomic nuclei of hydrogen-1 has an intrinsic magnetism which makes it, in essence, a bar magnet and most MRI (magnetic resonance imaging) has been generated using hydrogen-1 resonance. By the mid 1980s, MRI of hydrogen-1 nuclei was being used to locate tumors, strokes, multiple sclerosis, scars and other lesions. The clinical usefulness of MRI is that no X-radiation is delivered to the body. This means that MRI can be used safely in infants, children and pregnant women. MRI will probably replace CAT and other forms of X-ray imaging in diagnostic radiology.

C. PETT

New computer imaging techniques have made possible a sophisticated version of radioisotope scanning called PETT, or positron emission transaxial tomography. An injected radioactive isotope moving through the body emits positrons which collide with electrons in body cells resulting in mutual annihilation and release of gamma rays. A computer turns the information into a coloured map of the body's metabolism. The PETT scan could eventually become a routine part of psychiatric diagnosis of more than one kind of mental illnesses.^[3]

D. Evoked Potential Testing

Measuring the electrical activity of the brain is another way of finding disorders and exploring brain function. Minute changes (evoked potential) in electrical voltage, are the brain's response to sensory stimuli and the computer can identify the specific brain-waves created by the stimulus. Evoked-potential testing is ideal for detecting vision and hearing defects in new-born infants and can prevent life-long impairment. It can also be used to determine the cause of a child's poor scholastic performance, to assess brain damage, to diagnose brain tumors and multiple sclerosis.

E. Neurosurgery / microsurgery

Important progress in the treatment of brain disorders has also been achieved through drug research and advances in neuro-surgical techniques have kept stride with drug research. Development of ara-A, a drug used to combat the deadly virus herpes encephalitis marks a medical milestone. Similarly, microsurgery is saving the lives of many potential victims of stroke, the most common brain injury. Using fine tools and a microscope, surgeons divert an artery from scalp to brain in hopes of increasing blood supply and preventing stroke. It has also boosted the success rate for operations to remove weaknesses in the walls of brain arteries.

The most radical form of neurosurgery, the brain transplant, has already been performed with surprising success on Rhesus monkeys. Less awesome than the total brain transplant is the grafting of selected areas of the brain. Researchers believe brain grafts might relieve Parkinson's disease and other human neurological disorders as well.

F. Psycho-Neuro-Immunology

The mind itself may play a role in curing disease. It is now well established that negative emotions can upset body chemistry and bring on disease. Positive emotions have the opposite effect. A recent new research discipline, psycho-neuro-immunology shows that systematic pursuit of salutary emotions and technique of auto-suggestion alleviates chronic pain and retard degenerative diseases.

As scientists penetrate the substance of the brain with grafts and transplants, pacemaker machines and drugs for controlling brain functions, a fundamental question arises: To what extent can we manipulate the brain - precious sustainer of life, physical basis of mind - before the very essence of life itself is transformed?

The challenge of unfolding the brain's mysteries is a compelling one - can man discover the mechanism of thinking, and whether, by so doing, can he achieve new orders of understanding the dimensions of his own nature?

PRECAUTIONARY NOTE

Difficulties of Language regarding Terminology

In the chapters which follow, we have tried to discuss human attitude and behaviour from two different lines of thought. Since we are obliged to use the same language for expressing both lines of thought, it is prudent to explain the concepts of a few fundamental terms in each line of thought to avoid serious difficulties in specifying the use of these words in the text.

1. Consciousness and Soul

1. The term 'Consciousness' is considered a misleading term and is very much disliked by some Metaphysicians. They consider "self-consciousness" as a psychological impossibility and strongly object to the use of the expression.^[4]
   
   
   Neuroscientists also use the term consciousness in a very limited sense to specify the state of a person in which the activating programs of brain allow experiencing and thinking, that is, the state which is diametrically opposite to unconsciousness. In saying that one is conscious, we mean that one is awake and aware and open to receive and give out information and the capacity to do this depends upon the operation of a system in the head, called brain. Thus conscious experience is entirely dependent on the activity of the brain. Sleep, drugs and brain-damage alter the condition of consciousness. Consciousness, therefore, is the name that is applied to the condition that is experienced. Unfortunately, our language is capable of describing our knowledge and our experience, but we get into serious difficulties when we try to use the language to describe the knower. And the difficulty becomes unsurmountable because the 'knower' is not accepted by neuroscience as an eternal non-physical entity.
   
   
2. According to the doctrine of karman, the soul - the eternal, non-physical conscious substance - is the ultimate 'knower'. Knowing and experiencing are inherent in the soul. Knowledge can be born or rather emerge with or without the help of sense-organs and mind which are, however, only external instruments, the different states of the soul being their spiritual counterparts. The soul could never be bereft of consciousness. Even one-sensed organisms, such as plants, do possess the feeling of touch and can experience pain. These organisms are asaṁjñī i.e., they do not possess a brain or mind. But by suitable electronic apparatus, not only the pain but their awareness and expression of the pain can be recorded and studied.^[5]

2. Soul and Mind

Many psychologists, metaphysicians and others use the terms 'mind' and 'soul' as virtually interchangeable names of the object studied by psychologists. So far as there is any definite distinction of meaning between the terms as currently used by English writers, 'soul' seems to carry with it more of the implication of substantiality and relative independence than 'mind'. Some writers prefer to use the term 'spirit' for soul in the sense here suggested.

Those who do not believe in the ultimately real dualism i.e., separate existence of the two systems - the (mechanical) physical system i.e. the body and psychical entity or system i.e. the soul - cannot find the connection which subsists, as an actual fact, between body and soul but are forced to invent a connection in keeping with the general scheme of physical and psychological hypotheses.^[6]

3. Mind and Brain

1. Neuroscientists (and others) commonly refer to mind as an entity comprising the operations of the brain during the periods of awareness. No one has any direct perception of this as an entity and, in some senses, we know even less about it than about the brain. It clearly has no physical attributes and one cannot see or hear or touch it. It, however, is useful as a description of the general mode of operation of the brain and is sometimes described as the functional organization of the brain. But the brain performs many functions of which we are not aware and, therefore, the mind is perhaps that part of the brain's functional organization of which we are conscious. But even at best, it is really a vague concept.
   
   
2. In Jain philosophy, mental activity is differentiated from physical or muscular entity (which includes vocal activity or speech). All the three are controlled by the non-physical entity 'citta' which is the psychic component of the soul animating the physical body including brain. The term manaḥ is the closest translation of the term mind and is commonly used to distinguish it from the body (śarīra). Manaḥ has two functions - conceiving and perceiving. It is associated with sense-organs in the process of perception and is associated with memory and planning etc. in the process of conception. Thus, in reality, manaḥ is activated only when it functions and becomes amanaḥ (non-mind) during the periods of non-functioning. Thus it is to be regarded as an external instrument of mental functions, while citta is its activator and psychic master.