ekkentros free thoughts - pain

Dr.Thomas: Dalai Lama was once invited to a Psychiatric conference. In the course of the discussions he was asked to comment on the observation of some of the participants that the ‘God feeling’ that some ‘godmen’ claim to experience is a sort of a disease of the mind like epilepsy. The Lama replied that with all the modern scientific advancement and technology available to them if the scientists are able to produce a similar condition of ‘god feeling’, or the divine state of the mind, he would be only too happy. It would hardly matter whether it is achieved through stimulation of the brain by instrumental probes or by some other means.
The divinity in great saints like Ramakrishna Paramahans or Ramana Maharshi appear like madness or epileptic attack to people who do not understand.

The conversation before the start of the main discussion slowly veered around the question where exactly the perception of the PAIN starts and who is the perceiver, sufferer or the feeler? The pain may be localized, say, in the toe. The person feels the pain in the toe. The pain receptors take the signals, and through a network of nerves carry them to the brain. Does only the brain ‘feel’ the pain. Or the nerves all through also feel the pain, or the whole body, every cell, feels it? In anesthesia or when a person is unconscious, he does not feel the pain although he is fully alive and all normal bodily functions are active. That would indicate/suggest that consciousness is the perceiver or feeler of the pain. But if the communicating nerves are numbed or cut then also the consciousness cannot feel the pain. The mind of course feels the pain in another way. When it is anxious it can panic, and the panic magnifies the nagging pain. But the main question remains as to who is the direct sufferer of the pain. Mind is part of consciousness. Is the mind the feeler as well as the sufferer? The whole question is intriguing and requires unraveling.
Professor Sankarankutty remarked that there arises the age-old question of the observer and the observed. Who is the observer of the pain? The pain is objectified here, and there is always a distance between the observer and the pain that is being observed. Here, it is not a detached observation. The space between the pain and the feeler of pain is much reduced. Is the pain itself then the feeler of pain and also the consciousness at the moment of pain? There is also the question what is consciousness? Is it synonymous with awareness? And is not consciousness or awareness of something different from pure awareness/ pure consciousness without an object?
All these questions are left for deeper thought and later discussion.



After the Forum’s invocation, the discussion was continued by Dr. Babu Ravindran.

Dr. Babu Ravindran: Generally speaking, pain is an unpleasant sensation located in a part of the body. It’s positive aspect is that it is a protective mechanism meant for preservation of life.
There are two types of pain in general, described as penetrating or emotional. The penetrating type is tissue destructive and can be variously described as stabbing, burning, twisting, tearing, or squeezing. The emotional type is felt as extreme discomfort or uneasiness. Some pain of higher intensity is accompanied by anxiety, and an urge to escape or to terminate the feeling. The duality of Pain is that it involves both sensation and emotion.
When pain is acute it is characteristically associated with behavioral arousal and stress response like Increased Blood Pressure and heart rate, and Cortisol Release. In addition, local muscle contraction, viz., limb flexion and muscle rigidity are present. These responses are necessary for immobilization and protection of the affected part of the body.
How is the pain perceived? There are specialized nerve cells or neurons called receptors throughout the body. Pain receptors are part of the peripheral nervous system consisting of sensory nerves, motor nerves and sympathetic nerves. The receptors sense the pain impulses and pass them on to the sensory nerves. The sensory nerves pass on the impulses to the spinal chord or the brain. After processing by the network of nerves in the brain or spinal chord the instructions for action are passed on through the motor nerves to the various parts of the body. When there is very sudden detection of pain the impulses do not go all the way to the brain. Quick and immediate instructions for reaction go from the spinal chord itself. This results in what is called Reflex Action. It is a reflex arc from receptors to the sensory nerves to spine to motor nerve and the executing tissues. An example can be seen in the functioning of bladder muscles when it is full. The immediacy of the sensation to pass urine goes as impulses to the spinal chord and if the pathways to the brain are blocked or injured, reflex action works, and immediate instruction to hold the urine goes to the bladder muscles at once from the spinal cord itself.
Peripheral nerves are of three different types. 1. Sensory afferent 2. Motor efferent, and, 3. Sympathetic. The sensory nerves are afferent in the sense that impulses are directed towards the spinal cord. The cell body of the sensory nerve is the dorsal root ganglia. Axon of the nerve bifurcates into two, one going to spinal cord and the other to the tissue. Impulses from the organs of the body are passed on to the central nervous system by these nerves. The motor neurons on the other hand pass on impulses of instructions from the central nervous system to parts of the body. The sympathetic nerves help carry out the involuntary functions.
The vertebra protects the spinal cord. The sensory nerves are in the posterior of the spinal cord, and the motor nerves in the anterior. Similarly the sensory cortex is in the posterior part of the cortex of each hemisphere of the brain, and the motor cortex is in the anterior part. The main nerves go out from the spinal cord towards various parts of the body through the gaps in the vertebra called the Intervertebral foramen.
Nerves in general are of three different types, viz. A beta, A delta, and C.
Ab type of nerves is of large diameter, and carries the light touch. It is not associated with deeper pain but is present in superficial pain (minimal pain) and skin numbness.
Ad type is myelinated (i.e. sheathed), of small diameter, fastest and very sensitive. Pain is felt by this nerve much more than by other types.
C type is unmyelinated. It is also pain sensitive but to a lesser degree than type Ad. It has pain receptors called noceceptors
If the Ad type and C type are blocked, the ability to detect pain is abolished. But if Ab is blocked the pain will still be there unless the nerve itself is damaged.
When there is tissue injury, what are called inflammatory mediators like prostaglandins, bradykinins, and leukotrines are released. The presence of these creates more pain. This process is called sensitization. The affected area becomes more sensitive. Histamines are also produced. contributing to the increased pain. A typical example is the sunburned skin.
The sensory receptors called Noceceptors contain mediator polypeptides, like for example, a neuro transmitter called Substance P, which is also a vasodilator, contributing to increased pain. If substance p is blocked pain is decreased
Pain is not felt alike in all parts of the body. Intestines feel a pain only when it is stretched, not when it is cut. Although the brain perceives all pain, the brain material itself has no pain. Only the meninges, the outer covering membrane feels the pain.
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Then there is what is called Referred Pain. Sometimes when there is some visceral damage at or near the diaphragm, pain is felt at the shoulder skin. This is because the skin over the shoulder, and the diaphragm, has the same nerve supply. Their common blood supply is through cervical nerves C3 and C4.
We have all noticed that often fear and agony arise when a person is in pain. A reason for this can be found in the pattern of the nerve supply to the brain. Pain signals pass through the spinal tract called the Dorsal Spino-thalamus Tract and reach the Thalami. From the Thalamus the impulses go to the Sensory Cortex through the third order nerves. Now, the sensory cortex that senses the pain is pure sensation, and not emotion. But from the Thalamus the pain signals not only go to the sensory cortex but also go simultaneously to the area in the brain called the Cingulate Gyrum linked to emotional receptors. Emotions like fear are thus triggered when pain is felt.

Pain Modulation: BEECHER’S World War II Survey found on investigation that some of the injured soldiers felt no pain in war although they had been feeling even minor pain in their house in peacetime. Actually it is the expectation of pain that induced pain without any noxious stimuli that is normally responsible for the sensation of pain. The brain does this by a sort of selective control of the pain transmitting nerves. When the brain expect pain the circuits starts the operation of modulation of the transmitting pathways that have links to hypothalami, mid-brain, and medulla The brain circuits have thus control over the pain transmitting neurons. In war the brain utilizes this facility for relieving of pain. The brain circuits cause the release of pain relieving chemicals like. bEndorphin and Enkephalin. These chemicals are absorbed by the ‘opioid receptors’, so called because the chemicals Endorphin and Enkephalin are similar to natural Opioids.
Neuropathic pain: Damage or dysfunction of a portion of a nerve produce pain. This is called neuropathic pain. An example is the pain due to the disease called Herpes Zoster. A person who is healed of Chicken Pox is not always free of the pox virus. Some of the virus get into the Ganglia of the patient and lies there dormant till the system becomes weak and vulnerable. Then the disease comes out erupting along the path of a particular nerve affected by the virus. There are thus painful eruptions of a particular nature and pattern along the path of the nerve. This is only one of the examples of neuropathic pain.
Ischaemic Pain: When the required blood supply does not reach a part of the body derangement of metabolism happens to that part, and the neurons in the area are affected thus producing pain. An example of ischaemic pain is Angina Pectoris. Lactate and Pyroate, which are pain-producing chemicals, accumulate in the affected part of the body causing pain.