ANVESHANA ALOCHAKA PITTA PHYSIOLOGICAL UNDERSTANDING

Transcription

1 ANVESHANA Review Article AYURVEDA MEDICAL JOURNAL ISSN: ALOCHAKA PITTA PHYSIOLOGICAL UNDERSTANDING Sreelekshmi G 1, Kulkarni Pratibha 2 1 PG Scholar, 2 HOD, Dept. of Kriya Sharira, Sri Dharmasthala Manjunatheswara College of Ayurveda & Hospital, Hassan, Karnataka, India Corresponding Author: lekshmi.bams@gmail.com ABSTRACT Among the subtypes of Pitta, Alochaka pitta is very important since its sthana is in one among the jnanendriya. It helps in Roopa grahana and Roopa alochana (Visual perception and analysis). The presence of various gunas of pitta and Agni mahabhoota predominance, make Chakshurindriya to perform all its karmas. Acharya mentioned two types of Alochaka pitta - Chakshurvaiseshika and Budhi vaiseshika. Both play an important role in Jnanotpatti. Manas also play a major role in Jnanotpattti. The functions of Alochaka pitta are possible only in the presence of mind. The support of Vata, makes Alochaka pitta to perform all its functions. With the help of contemporary science, the functions of both Alochaka pitta can be explained to understand the concept more clearly. The same efforts are made in this paper. Key words: Alochaka pitta, Chakshurindriya, Manas, Jnanotpatti INTRODUCTION Among the Tridoshas Vata, pitta and kapha, have 5 subtypes and they involved in different organs for performing different functions in our body. The subtypes of Pitta are Pachaka, Ranchaka, Sadhaka, Alochaka and Brajaka. The Alochaka pitta, which is associated with Chakshu (eyes) perform the functions Roopa grahana and Roopa Alochana (perception and analysis of image). The word Alochana itself means- Darsana and Vivechana (seeing and perceiving) in Sabdakalpadrumam. These functions are inevitable because without these, the whole world will be blind. So the presence of Alochaka pitta in Chakshurindriya is very important. The Presence of Agni mahabhoota in Chakshu also plays an important role in performing the function Roopa grahana. All the gunas of pitta make Chakshu more functional. The main aim of this article is to understand the functions of Alochaka pitta with its types and Gunas with the help of Manas and applying them to the Modern Science for clearing the concept. Sthanas and functions of Alochaka pitta All Acharya have the same opinion about the Sthana of Alochaka pitta it is Drishtistham, which is present in eyes 1. The word Drushti means Lochana, Nayana, Netra, Akshi, Chakshus. 2 The function of Drishti is Drik (helps in vision). The word Alochaka means Darsana 3.The pitta which is responsible for performing the function Darsana or Drik is the Alochaka pitta. It is situated in the innermost part of the eye known as Anthataaraka 4 as per one view. Acharya mentioned the term Darsana 5 (vision) while explaining the general functions of Pitta. In some references the word Tejo 6 is mentioned as the function.

2 Charaka did not mention the subtypes of Tridosha, but he was aware about their different functions and Sthanas. In Chakrapani commentary, it is mentioned that the word Darsana and Adarsana is mainly associated with Netra.Thetwo different terms mainly used for mentioning the function of Netra are Darsana and drik. Vata dosha helps in Aksha patavam. Aksha-means drik and Patavam means clarity. Pitta helps in darsana (vision) ie. Alochaka pitta. Vata is an inevitable factor for each and every processes of Darsana and make Pitta to perform its karma. Netra does the function of Darsana due to the presence of Alochaka pitta along with other Doshas. The two kinds of Alochaka pitta 7 mentioned are Chakshurvaiseshika Alochaka pitta and Budhivaiseshika Alochaka pitta. According to him Chakshurvaisesikais situated in Chakshurindriya (sense organ-eye) and it functions in co-relation with Atma and Manas. Mana is an important tool in the process of learning and it gain knowledge through Indriyas only. Here Alochaka pitta in the Netra helps in the identification of objects and its perception such as the knowledge of colour, size, and shape etc, Budhivaisesika situated in Sringataka (area between the two eyebrows) enables concentration, recognition and response. It is also responsible for memory associated with experience through vision 7. The gunas of pitta and its significance Sneha, Teekshna, Ushna, Laghu, Visram, Saram, Dravamare the Gunas of Pitta 8. These gunas together helps in Roopagrahanam and Roopa Alochanam. The presence of Snehaguna, provide Snigdatva (lubrication or moistening) to the eyes by the production of various fluids. Teekshna Ushnaguna due to the predominance of Tejo mahabhoota which also has the same gunas, helps to absorb Prakasa (light energy) as well as in the Parinama or Paka of that light, that is the conversion of light energy into electrical energy or Impuses 9 Laghuguna helps in the movement of eyeball, easy movement of fluids such as tears, Acous humor and Vitreous humor and in the transmission of impulses. Visra and Sara guna helps in the unidirectional flow of fluids and impulses and the presence of Drava guna helps in the protection of eyes by the secretion of tears. Altogether Alochaka pitta helps in Roopa Alochana and finally Jnanolpatti. With the help of these gunas some diseases can be interpreted, such as Vitamin A deficiency, Black outs etc 9 : People who fast for a longer period may be affected with blackouts. Normally Ahara is converted into Rasa dhatu by the action of Agni. If it is improper, Rasa dhatu formation is decreased. The Rasa kshaya can results in delayed Photo transduction process and results in Black outs. Similarly in Vitamin A deficiency, some features such as Dryness of conjunctiva, dryness of Skin, softening of Cornea etc: occurs. They are mainly due to the decreased Snehaguna. Hence Rookshatva (dryness) and Balahani (decreased strength) increases and Vyadhikshamatva decreases 9. Various steps involved in obtaining jnana through Alochaka pitta Indriyartha Sannikarsha, Roopagrahana and Roopalochana (Visual perception &visual acquity or analysis of objects) Parinama (transformation and transportation of light energy into nerve impulses towards the Visual centre) results in Jnanotpatti 10. For Indriyarthasannikarsham the image or Roopa travels in the light medium towards the Indriya adhishtaanam which is the Akshi (eye).this perception of Indriyardha by Indriya takes place in through 3 stages. Conduction of light rays reflected from the object to the eyes, Refraction of light rays inside the eye and Convergence inside the eyes on Drishtipatalam (Retina). AAMJ / Vol. 1 / Issue 3 / May June

3 For Roopa alochanam This is considered to be the most complicated stage. Receiving and analysing the images occurs in this stage. The role of Alochakapitta is very important in this stage. When light rays falls on drishtipatalam, a series of reactions takes place. They are photochemical changes, Electrical changes and Nervous stimulation. These phenomenons can be explained under the headings such as Visual pathway, Visual process and Visual transduction. Visual pathway It is the nervous pathway that transmits impulses from retina into visual centre in cerebral cortex. In binocular vision, the light rays from temporal half of visual field fall upon the nasal part of corresponding retina. The rays from nasal half of visual field fall upon the temporal part of retina. Thus the Nasal fibres of Optic nerve carry temporal images and temporal fibres carry nasal images. Nasal or medial fibres form Optic Chiasm crossing over takes place. Finally these fibres along with the uncrossed temporal fibres form the Optic tract. They terminate at the Lateral geniculate body of Thalamus, from which Optic radiations arises, which finally terminates in the Visual centres of Visual Cortex 11. Visual process Visual process is a series of actions that takes place during Visual perception. During Visual process image of an object seen by the eyes is focused on retina resulting in the production of Visual perception of that object. Energy in visual spectrum is converted into electrical potentials/impulses by Visual receptors through some chemical reactions. Impulses from Visual receptors reach cerebral cortex through Optic nerve and sensation of vision is produced there. This process of visual sensation is explained on the basis of Image forming mechanism, neural phenomenon, Chemical phenomenon and electrical phenomenon 11. Image forming mechanism While looking at an object, light rays from that object are refracted and brought to focus upon retina. Image of the object falls on the retina is in an inverted position and reversed side to side. Inspite of this, the object is seen in an upright position. It is because of the role played by cerebral cortex 11. Neural phenomenon Presence of Rods and Cones is responsible for the visual processes. Rods have low threshold for light stimulus so sensitive to dim light vision or night vision. Cones have high threshold- So sensitive to bright light. Cones are responsible for Acquity of vision and Colour vision. The synaptic vesicles present in the synaptic terminal of both Rods and Cones contain the neurotransmitter, Glutamate. The decrease in the amount of Glutamate makes response in the bipolar cells and Ganglionic cells that produces an impulse which will be transmitted through the Optic nerve 11. Chemical basis of Visual Process Photosensitive pigments present in rods and cones are concerned with chemical basis of visual process. These Chemical reactions lead to the development of electrical activity in retina and generation of impulses (action potentials) and transmit through optic nerve. The impulses reach occipital cortex at a speed of 124 millisec after retinal stimulation. When light from an object is reflected and falls on retina, the Rhodopsin is decomposed into Metarhodopsin 11 which again undergo several decomposition. When dim light comes, the protein part called Scotopsin and the Chromophore part Retinal finally join together to form the Rhodopsin. In this way AAMJ / Vol. 1 / Issue 3 / May June

4 Rhodopsin helps in dim light vision or Night vision 11. Photo Transduction The process by which light energy is converted into Receptor potential in visual receptors is called Visual Transduction or Photo transduction. Here the Metarodopsin 11 activates a G protein called Transducin, which again activates an enzyme cgmpphosphodiesterase. This enzyme hydrolyses cgmp into 5-cGMP, that means there is a marked decrease in the level of cgmp concentration. This leads to the closure of Sodium channels in the Rod cells, as a result the negativity inside the cell increases. This hyperpolarisation leads to decrease in the secretion of the neurotransmitter-glutamate. This creates a response in the Bipolar cells and Ganglionic cells so that, the Action potentials are transmitted to cerebral cortex via optic pathway 11. Involvement of manas in jnanotpatti The function of Alochakapitta is possible only in the presence of mind. So it can be considered as the basement factor. We cannot identify an object in the absence of mind. So mentally retarded patients cannot identify or differentiate objects clearly 10. DISCUSSION The photosensitive chemicals in the eye and the whole process in the photochemistry of vision can be explained by the function of Alochakapitta. Neurotransmitters involved in the visual pathway can also be included under this pitta. By applying Nyayas (laws) such as Peelupaka and Pithara paka of Viseshika darshana, the above Photo chemical changes will be understood more, where they mentioned various physical and chemical changes of dravyas. In the process of Jnanotpatti, the Visual impulses formed in the inner part of eye, is first converted into actual Visual sense ie. Pratyakshajnaanam of the Roopam is developed first. The Visual impulses, collected by Alochakapitta are brought to the Budhi where it is stored, confirmed and reproduced. The fraction of this Alochakapitta which functions in Budhi is the Budhivaiseshika Alochakapitta. It is not inside the eyes; structurally it is the Visual centres in Occipital lobe, where the Visual sense or the Prathyakshajnanam develops. Any vitiation in the function of Alochakapitta brings out visual defects. In such cases, details of objects such as colour, shape, size etc: cannot be identified. Eg: Nakulandham, Hraswa etc: The Pancha mahabhoota predominance in various Bhaga of Netra 12 plays an important role in performing various functions. Presence of Prithvi Mahabhoota in Mamsa bhaga (muscles) helps to keep the Netra intact within the Netra guha (eye orbit). They also helps in several movements of Netra. Agni mahabhoota in the Rakta bhaga, provide Teekshna Ushna Guna that helps in the Paka or Parinama of Prakasha which is absorbed. Jala mahabhoota in Sweta mandala provide Drava, Sara guna and helps in lubrication and protection. Asru mandala which is Akasa mahabhoota predominant provides Laghu guna, which helps in the easy passage of fluids such as Ashru. Vayu mahabhoota in Krishna mandala helps in the absorption of Prakasha by the Sankocha and Vikasa karma of Mamsa. It also provides laghutva for the easy transmission of Roopa towards the center and makes Alochaka pitta more active. CONCLUSION Thus the presence of 2 types of Alocakapitta - Chakshurvaisesika and Budhivaisesika, with the support of Vata and Manas perform the major functions like Roopa grahanam and Jnanotpatti. Chakshurvaisesika, helps in perceiving the AAMJ / Vol. 1 / Issue 3 / May June

5 light and conversion of light energy into electrical energy. Budhivaisesika-transmits that electrical energy in the form of impulses or action potentials into the region of Budhi or Visual cortex for the purpose of Jnanotpatti. REFERENCES 1. R. B. Rama. Ashtanga sangraha of Vagbhata. Sootra sthana; Doshbhedeeyam: 20, 2. Varanasi: Chowkambha Vishwabharati oriental publishers, 2006: p Pt. Harigovinda Sastri. Amarakosha (Namalinganusasana of AmaraSimha); 5. Varanasi: Krishnadas Academy; Sabdakalpadrumam 4. R. B. Rama. Ashtanga sangraha of Vagbhata. Sootra sthana; Doshabhedeeyam: 20, 7. Varanasi: Chowkambha Vishwabharati oriental publishers, 2006: p R. B. Rama. Ashtanga sangraha of Vagbhata. Sootra sthana; Doshadivinjaneeyam: 19, 3. Varanasi: Chowkambha Vishwabharati oriental publishers, 2006: p M. K. R. Srikantha. Susruta Samhita of Susruta. Sootra sthana; Doshadhatu mala kshaya vridhi vijanam: 15,4.Varanasi: Chowkambha Orientalia, 2012: p K. H. Krishnamurthy, P.V.Sharma. Bhela Samhita of Bhela. Shareera sthana; Purushanicayam saareeram:4, 4-5.Varanasi: Chowkambha Vishvabharati publishers, 2008: p R. B. Rama. Ashtanga sangrah of Vagbhata. Sootra sthana; Ayushkameeyam: 1, 28.Varanasi: Chowkambha Vishwabharati oriental publishers, 2006: p 9 9. Balakrishnan P, Ashwini M. J. Conceptual analysis of Physiology of Vision in Ayurveda. J-AIM. 2014; 5(3): p P. K. Santakumari, Textbook of Ophtalmology in Ayurveda. Thiruvanandapuram: Minerva offset; 2002: p K. Sebulingam, Prema Sebulingam, Essentials of Medical physiology. NewDelhi: Jaypee brothers Medical publishers; 2010: p M. K. R. Srikantha. Susruta Samhita of Susruta. Uttara sthana; Oupadravikamadyayam: 1, 11. Varanasi: Chowkambha Orientalia, 2012: p 4 How to cite this article: Sreelekshmi & Pratibha. Alochaka Pitta Physiological understanding, AAMJ 2015; 1: Source of Support: Nil. Conflict of Interest: None declared AAMJ / Vol. 1 / Issue 3 / May June