|Year : 2010 | Volume
| Issue : 1 | Page : 111-113
Prevalence of touch sensation (Sparshanendriya-Vyapaktva)
Ajay Kumar1, Tina Singhal2, BN Upadhyay1
1 Dept. of Kayachikitsa, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
2 Dept. of Rachna Sharir, Institute of Medical Sciences, Banaras Hindu University, Varanasi, India
|Date of Web Publication||7-Aug-2010|
Dept. of Kayachikitsa, Institute of Medical Sciences, Banaras Hindu University, Varanasi
Source of Support: None, Conflict of Interest: None
| Abstract|| |
There are much more topics in our Ayurvedic classics about which we have limited knowledge. Like this an another topic is Indriya. We don't know what is indriya or what are their sites. Are the organs by which we perceive sensation called Indriya or different from them? Acharya Charaka has told five types of Indriyas, Sparshanendriya, Chakshurendriya, Ghranendriya, Rasanendriya & Shravanendriya. He also described their sites, functions, composition, and their properties. But he also told that Sparshanendriya is the main Indriya and it is present in all Indriyas. Why Charaka told that Sparshanendriya is Vyapak in all Indriyas. Is this concept wrong or right? The answer is right & this concept can be proved by following means as described in this paper.
Keywords: Vyapaktva, Sparshanendriya, Touch, Charaka.
|How to cite this article:|
Kumar A, Singhal T, Upadhyay B N. Prevalence of touch sensation (Sparshanendriya-Vyapaktva). AYU 2010;31:111-3
| Introduction|| |
Indriyas are the organ of sensation. According to Charaka indriyas are formed from panchamahabhutas  & according to Sushruta these are originated from ahamkβr. When indriya, mana and indriyartha communicate with each other they cause acquaintance of knowledge  . Generally indriyas are of two types -
- Gyanendriya: Involved in the acquaintance of knowledge.
- Karmendriya: Involve in daily routine work.
Further Gyanendriya are of five types  :
The site of Sparshanendriya is the skin. Although Sparshanendriya is Panchabhautik, yet there is predominance of Vata in Sparshanendriya. According to Charaka, among all Indriya, Sparshanendriya is the main and present in all indriyas. There are various references present in texts showing the Vyapaktva of Sparshanendriya in all Indriyas  .
This concept of Charaka is very true and scientific. In fact, all indriyas communicate with their own indriyartha via touch. In absence of contact or touch with own indriyartha, no any indriya could do their normal functions. In this paper it has been tried to explain this concept on modern criteria.
1. Touch Sensation (Sparshanendriya)
Skin is considered as the largest sense organ in the body. It has many nerve endings which are specialized to form cutaneous receptor  . The dermis of the skin and the subcutaneous tissue contain receptors for the sensations of touch, pressure, heat, cold, and pain. The receptors for pain, heat, and cold are free nerve endings, which also respond to any intense stimulus, intense pressure, for example, may be felt as pain. The receptors for touch and pressure are encapsulated nerve endings, meaning that there is a cellular structure around the nerve ending. These receptors are stimulated by sensation of touch, pain, pressure and temperature and convey these sensations through the afferent nerve to brain  . At various levels of impulse conduction one nerve touches to other and transmit its message.
2. Visual Sensation (Chakshurendriya)
The eye contains the receptors for vision and a refracting system that focuses light rays on the receptors in the retina. When the light rays fall on and touch the visual receptors (rods & cones) various changes occur in this receptor resulting in viewing of an object. When light rays strike the retina, they stimulate chemical reactions in the rods and cones. In rods, the chemical rhodopsin breaks down to form scotopsin and retinal (a derivative of vitamin A). This chemical reaction generates an electrical impulse, and rhodopsin is then resynthesized. The impulses from the rods and cones are transmitted to ganglion neurons ; these converge at the optic disc and become the optic nerve,which passes posteriorly through the wall of the eyeball  . Here light rays touch the receptors and then a series of events occur. If this contact will not happen then vision could not be possible. So touch is necessary for the complete pathway of visual sensation.
3. Sensation of Smell (Ghranendriya)
The receptor cells for the smell sensation are the olfactory cells, which are actually bipolar nerve cells derived originally from the central nervous system itself  . The olfactory receptors are chemoreceptors that detect vaporized chemicals that have been sniffed into the upper nasal cavities. Just as there are specific taste receptors, there are also specific scent receptors, and research indicates that humans have several hundred different receptors  . When stimulated by vapor molecules, The molecules get dissolved in the mucus and it comes in contact with intra-membranous particle contained within the cilia of the receptor cells and combine with these particles & then olfactory receptors generate impulses carried by the olfactory nerves (1 st cranial) through the ethmoid bone to the olfactory bulbs  . The pathway for these impulses ends in the olfactory areas of the temporal lobes of brain causing perception of smell.
4. Taste Sensation (Rasanendriya)
Taste is mainly a function of the taste buds in the mouth, but it is common experience that one's sense of smell also contributes strongly to taste perception. In addition, the texture of food, as detected by tactual senses of the mouth, and the presence of substances in the food that stimulate pain endings, such as pepper, greatly alter the taste experience  . The taste receptors are found in taste buds, most of which are in papillae on the tongue. These are chemoreceptors which are stimulated by substances dissolved in mouth by saliva. The chemicals are foods and the solvent is saliva (if the mouth is very dry, taste is very indistinct). The dissolved substances acts on microvillus of taste receptor exposed in the taste pore. This causes development of receptor potential in receptor cells. This in turn is responsible for the generation of an impulse going to appropriate part of brain resulting in sensation of taste. The impulses from taste buds are transmitted by the facial and glossopharyngeal (7 th and 9 th cranial) nerves to the taste areas in the parietal-temporal cortex  . In the whole pathway of taste sensation, touch is required at different levels of nerve conduction. If touch not takes place at any level then we could not perceive taste.
5. Hearing Sensation (Shravenendriya)
The process of hearing involves the transmission of vibrations and the generation of nerve impulses. When sound waves enter the ear canal,vibrations are transmitted by the following sequence of structures: eardrum, malleus, incus, stapes, oval window of the inner ear, and perilymph and endolymph within the cochlea.The sound waves which are transmitted by the tympanic membrane, malleus and incus cause the movement of stapes . This leads to the origin of vibrations in the fluid of cochlea. The vibrations now stimulate the hair cells in organ of corti. The basilar membrane ripples and pushes the hair cells of the organ of Corti against the tectorial membrane. When the hair cells bend, they generate impulses that are carried by the 8th cranial nerve to the brain  . This in turn causes generation of action potential in auditory nerve fibers. When the auditory impulse reaches the cerebral cortex the perception of hearing occurs.
| Discussion|| |
'Shravendriyanam vyapaka Sparshakrito'  this quotation of Charaka is very scientific & this shows that our Acharyas have high level of scientific thinking. In present era, we really not try to understand the main theme of our classical texts but only think its superficial aspects & tell that old texts are unscientific. In above lines it has been tried to explain this small quotation on modern backgrounds & it proves that sparshanendriya is present in all indriyas.
| Conclusion|| |
Even though there are five sense organs with the coreesponding five objects of theirs,but as matter of fact there is only one sense faculty which pervades all the sense organs. No sensation can occur without a sense of touch. So it is the tactile senasation which predominates all the sensation  .
| References|| |
|1.||Shastri K N & Chaturvedi G N, 1984, Charak Samhita with Vidyotini Hindi Commentary, Chaukhambha Bharti Academy, Varanasi, 12th ed, Chapter 8, Shloka 8, p. 176. |
|2.||Ibid. Chapter 8, Shloka 7, p. 176. |
|3.||Ibid. Chapter 28, Shloka 31, p. 782. |
|4.||Ibid. Chapter 11, Shloka 38, p. 230. |
|5.||Sembulingam K, 2001, Essential of Medical Physiology, Jaypee Brothers Medical Publication, New Delhi, India, 2nd ed, Chapter 61, p. 259. |
|6.||Chaudhari S K, 2001, Concise medical Physiology, New Central Book Agency Pvt. Ltd., Calcutta, India, 3rd ed, Chapter VIII. 6, p. 384. |
|7.||Arthur C. Guyton, John E. Hall, 2006, Textbook of medical physiology, Elsevier Inc, Philadelphia, Pennsylvania, 11th ed, Chapter 50, p. 628. |
|8.||Ibid. (6), Chapter XB 2.5, p. 477. |
|9.||Ibid. (5), Chapter 177, p. 807. |
|10.||Ibid. (7), Chapter 53, p. 663. |
|11.||Ibid. (6), Chapter XB 2.5, p. 481. |
|12.||Ibid. (7), Chapter 52, p. 657. |
|13.||Ibid. (1), Chapter 11, Shloka 38, p. 230. |
|14.||Sharma R K and Dash B, 2007, Charak Samhita, Chaukhambha Sanskrit Series Office, Varanasi, Vol. 1, Chapter 11, Shloka 38, p. 223. |