|Year : 2022 | Volume
| Issue : 1 | Page : 5-11
Alochaka Pitta of Ayurved and its affiliates in modern perspective
Pritam Moharana, Rakesh Roushan
Department of Kriya Sharir, Sri Sri College of Ayurvedic Science and Research Hospital, Sri Sri University, Cuttack, Odisha, India
|Date of Submission||11-Jan-2022|
|Date of Decision||13-Apr-2022|
|Date of Acceptance||21-Apr-2022|
|Date of Web Publication||15-Jun-2022|
CH Brahm Prakash Ayurved Charak Sansthan, Delhi
Source of Support: None, Conflict of Interest: None
In Ayurved, a person is said to be healthy when Dosha, Agni, and Dhatu, all the physiological processes are in a homeostatic state and the soul, sense organ and mind are in a state of total well-being. The theory of tridosha is a unique concept to Ayurveda. In general, Pitta doshas are liquid in nature except pachaka pitta which has devoid of liquidity. Acharya Sushrut has mentioned five types of pitta. Those are Pachaka, Ranjaka, Alochaka, Bhrajaka, and Sadhaka pitta. The seat of Alochaka pitta is drishti and function of Alochaka pitta is vision. Ayurveda is the science-based on functional understandings. Hence, Alochaka pitta can be identified by understanding its physiological functions in relation to contemporary modern medical science. The functions of Alochaka pitta can be recognized as functions of photochemicals (rhodopsins and color pigments) of rod and cone and the neurotransmitter that helps in communication between neurons throughout the visual pathway between the retina and visual cortex. Few works have been mentioned on the conceptual features of Alochaka pitta in relation to modern physiology. In this article, we intended to identify liquid bio-chemicals, helpful in perception of vision, provided no lesion is present in the visual pathway. The physiological functions of these bio-chemicals may have similar physiological functions of Alochaka pitta.
Keywords: Alochaka pitta, Ayurveda, Buddhi Vaisheshika, Chakshyu Vaisheshika, neurotransmitter, photoreceptors
|How to cite this article:|
Moharana P, Roushan R. Alochaka Pitta of Ayurved and its affiliates in modern perspective. Indian J Ayurveda lntegr Med 2022;3:5-11
|How to cite this URL:|
Moharana P, Roushan R. Alochaka Pitta of Ayurved and its affiliates in modern perspective. Indian J Ayurveda lntegr Med [serial online] 2022 [cited 2022 Aug 8];3:5-11. Available from: http://www.ijaim.in/text.asp?2022/3/1/5/347496
| Introduction|| |
Theory of tridosha is a unique theory in the indigenous system of medicine. Pitta in general does the bodily functions related to digestion and metabolism. All metabolic and catabolic activities, biochemical reactions, and the process of energy exchange are due to pitta. There is always involvement of pitta dosha in every reaction or changes take place inside our body. Pitta dosha is present at all levels of organizations, i.e., cellular level, single system level, and organization level. Pitta dosha does not move in the body independently. It is circulated all over the body with the help of Vata dosha. In modern physiology, it has been mentioned that the basic theory of the body's control system allows the functional system to operate in support of one another. Vata, Pitta, and Kapha are body control systems and they regulate bodily functions in support of one another. Pitta dosha has been divided into five types on the basis of location, namely Paachak, Ranjak, Saadhak, Alochaka, and Bhrajaka pitta. All these five types of Pitta doshas have their different l0 locations and functions as well. Alochaka pitta is present in the eye responsible for normal vision. On the basis of functional understanding, the photosensitive chemicals in the eye called photopigment and the whole chemical processes involved in the photochemistry of vision, neurotransmitters involved in the visual pathway from the retina to visual cortex may be represented as Alochaka pitta.
Alochaka pitta cannot be represented by a single entity at all the time. There are variations in the functions of Alochaka pitta. Based on the functions of Alochaka pitta, we can identify a variety of chemical factors based on contemporary modern medical sciences responsible for the same functions. Ayurveda is the science based on the concept of functional understanding of the body, by considering its functions, the entities representing can be assumed.
At present time, students with a background of biology, physics, and chemistry got admitted in the 1st year of Bachelor of Ayurvedic Medicine and Surgery. They face a lot of problems in understanding the basic concept of Ayurveda and its jargon because of their basic science background. They are not familiar with Ayurvedic terminology. There is no specific correlation of Alochaka pitta mentioned in Ayurvedic literature in terms of supporting modern literature. Increased demand of Ayurveda science is required to understand the depth of Ayurvedic principles on the criterion of modern medical science in an easy mode. Acharya Bhela has classified Alochaka pitta into two types, i.e., Chakshyu vaisheshika and Buddhi vaisheshika. Chakshyu vaisheshika is for the perception of vision, whereas the function of Buddhi vaisheshika is to differentiate the things from each other, to compare with previous experience or to remember it for future use. In this review article, we are trying to identify bio-chemicals in the human body based on the physiological functions of Alochaka pitta retrospectively.
| Modern Aspects|| |
All the ancient acharya have mentioned Alochaka pitta is residing in drik (eye). Commentator Indu has mentioned the site of Alochaka pitta is antah taraka (Retina) of netra. The function of Alochaka pitta is to perception of vision. The retina is the light-sensitive portion of the eye that contains rod and cone cells. Cones are responsible for color vision and rods can detect dim light and are mainly responsible for black and white vision and vision in the dark. Light and dark stimuli stimulates the cones or rods; signals are transmitted first through the successive layers of the retina and finally into optic nerve fibers and the visual area of the cerebral cortex.
The retina consists of 10 layers. After light passes through the lens system of the eye and then through the vitreous humor, it enters the retina from inside of the eye that is it passes first through the ganglion cells and then through the plexiform and nuclear layers; finally, it reaches to the layer of rods and cones located on the outer edge of the retina. The major functional segments of either a rod or cone are outer segment, inner segment, nucleus, and synaptic body. The light-sensitive photochemicals are found in the outer segment. In case of rod, this photochemical is rhodopsin, and in cones, it is usually called color pigments. Both rhodopsin and color pigments are conjugated proteins. The inner segment contains mitochondria which provide energy for the functions of the photoreceptors.
| Photochemistry of Vision|| |
Both rod and cones contain chemicals that decompose on the exposure to light. In this process, it excites the nerve fiber leading from the eye. The light-sensitive chemical in the rod is called rhodopsin and the light-sensitive pigment in cones is called color pigments. Rhodopsin is the combination of protein scotopsin and the carotenoid pigment retinal. This retinal is a type of 11 cis-retinal. This cis form of a retinal bind with scotopsin to synthesize rhodopsin.
| Decomposition of Rhodopsin by Light Energy|| |
When the light energy is absorbed by rhodopsin, the rhodopsin begins to decompose within a very small fraction of a second. The cause of this rapid decomposition is the photoactivation of electrons in the retinal portion of rhodopsin which leads to an instantaneous change of cis form of retinal to trans form of retinal.
All trans retinal is no longer fits with the orientation of reactive sites on the protein scotopsin. All trans retinal begins to pull away from the scotopsin and the immediate product is bathorhodopsin which is a combination of trans retinal and scotopsin. Bathorhodopsin decays in a nano second to lumirhodopsin. This product is then decayed in microsecond to metarhodopsin-1 then about a millisecond to metarhodopsin-2 and finally into the complete split product of scotopsin and 11 cis retinal. Metarhodopsin-2 is the activated rhodopsin that excites electrical changes in the rods and the rods then transmit the visual image to the visual cortex in the form of the action potential.
| Reformation of Rhodopsin|| |
Light-sensitive chemical is called as rhodopsin. This rhodospin is formed in the absence of light and helps in night or dark vision. The first stage in the reformation of rhodopsin is to reconvert all trans retinal into 11 cis retinal. This process requires metabolic energy and is catalyzed by the enzyme retinal isomerse. Once 11 cis retinal is formed it recombines with scotopsin to reform rhodopsin. There is a second chemical route by which all trans retinal can be converted into 11 cis retinal. First all trans retinal is converted into all trans retinol which is a one form of vitamin A, then all trans retinol is converted into 11 cis retinol under the influence of the enzyme isomerase. Finally, 11 cis retinol is converted into 11 cis retinal which combines with scotopsin to form rhodopsin. In [Figure 1], rhodopsin retinal cycle in rod is mentioned.
| Excitation of Rod When Rhodopsin Is Activated by Light|| |
When rhodopsin is formed and excites the rod. When the rod is exposed to light, there is the excitation of the rod that causes hyperpolarization. When rhodopsin decomposes, it decreases the rod membrane conductance for sodium ions in the outer segment of the rod. The inner segment of the rod continuously pumps sodium ions from inside the rod to the outside and potassium ion to the inside of the cell. Potassium ions are leaked out of the cell through nongated potassium channels. However, the outer segment of the rod where the photoreceptor discs are located is entirely different. Here the rod membrane in the dark state is leaky to sodium ions that flow through cyclic guanosine monophosphate (cGMP)-gated channels. In the dark state, cGMP levels are high permitting positively charges sodium ions to continually leak back to the inside of the rod and thereby neutralizing negativity on the inside of the entire cell. Under normal dark conditions when the rod is not excited, there is reduced electronegativity inside the membrane of the rod. When rhodopsin in the outer segment of the rod is exposed to light, it is activated and begins to decompose. The c-GMP-gated sodium channels are then closed and the outer segment membrane conductance of sodium to the interior of the rod is reduced by three processes.
- Light is absorbed by the rhodopsin causing photoactivation of the electrons in the retinal portion
- The activated protein stimulates a G-protein called transducin which then activates c-GMP phosphodiesterase (an enzyme that catalyzes the breakdown of c-GMP to 5' c-GMP)
- The reduction in c-GMP closes the c-GMP-gated sodium channels and reduces the inward sodium current.
Thus more sodium ions now leave the rod and then leak back in. It causes hyperpolarization.
| Photochemistry of Color Vision|| |
Photochemicals in the cones are responsible for color vision. It is almost exactly the same chemical composition as that of rhodopsin in the rod. The protein portion of the photochemicals in the cones is called photopsin. Blue, green, and red are the three color pigments present in the cone.
| Optic Pathway|| |
The first light passes through the lens system of the eye and then through the humor, it enters the retina from inside of the eye. The different neuronal cell types in the retina are photoreceptors, horizontal cells, bipolar cells, amacrine cells, and ganglion cells. Photoreceptors like rod and cones which transmit signals to the outer plexiform layer where they synapse with bipolar cells and horizontal cells. Horizontal cells transmit signals horizontally in the outer plexiform layer from the rods and cones to bipolar cells. The bipolar cells transmit signals vertically from the rods and cones and horizontal cells to the inner plexiform layers where they synapse with ganglion cells and amacrine cells. Amacrine cell transmits signal in two directions either directly from bipolar cells to ganglion cells or horizontally within the inner plexiform layer from axons of the bipolar cells to dendrites of the ganglion cells or other amacrine cells. The ganglion cell transmits the output signal from the retina through the optic nerve into the brain.
The first-order sensory neurons carrying visual sensation are the bipolar cells of the retina. Their dendrite synapse with rods and cones and their axons with dendrites of ganglion cells. The second-order sensory neurons are the ganglion cells. Axons arising from the ganglion cells form the fibers of the optic nerve. The right and left optic nerve join to form optic chaisma, where fibers from nasal of the retina cross to the opposite side and travel through the opposite optic tract to terminate in the opposite lateral geniculate body. The fibers from the temporal half of each retina enter the optic tract of the same side to terminate in the ipsilateral geniculate body. The cell bodies of the third-order sensory neurons are located in the lateral geniculate body. Their axons form the optic radiations project to the visual cortex.
Based on the functions of Alochaka pitta, we can identify a variety of chemical factors based on contemporary modern medical sciences responsible for the same functions. The chemical factors are none other than the neurotransmitters responsible in the optic nerve pathway. Rhodopsin, iodopsin, bathorhodopsin, lumirhodopsin, metarhodopsin-1, Metarhodopsin-2, isomerase enzyme, and the neurotransmitter responsible for the communication in optic pathway may be represented as Alochaka pitta.
| Types of Alochaka Pitta|| |
Sthan (Location) and Karma (Function) of Alochaka pitta has been described by different Acharya mentioned in [Table 1]. Acharya Bhela has classified Alochaka pitta into two types: Chakshyu vaisheshika and Buddhi vaishehsika. Chakshyu vaisheshika is present in chakshyu of all type of living beings in all ages. It helps in perception of vision of all symptoms of bhootagrama such as sthan, roopa, varna, swara, pushpa, patra, phala, etc., by the combined effect of atma (soul) and mana (mind). Buddhi vaisheshika which is situated in shringataka located between the eyebrows helps to perceive adhyatmik knowledge from the very minute level, differentiate things from each other to compare with previous experience or to remember it for future use and to see the things without opening the eyes. Chakshyu vaisheshika pitta helps in the perception of visual images obtained from the present surroundings, whereas Buddhi vaisheshika pitta helps in analyzing the received information, generating thoughts, create ambition, and determining reaction.
The pathway from photoreceptors (rods and cones)-retina-optic nerve-optic chaisma-dorsal lateral geniculate nucleus of the thalamus-geniculocalcarine tract to the primary visual cortex is called as an optic pathway. The communication in this pathway is carried out by neurotransmitters which may be represented as Chakshyu vaisheshika pitta.
Visual perception of the language through reading develops the visual image in the cortex, information goes to Wernicke area through the angular gyrus area for proper knowledge regarding that object. Angular gyrus area is needed to make meaning out of the visual perceived word. Wernicke area is the region of the entire brain for higher intellectual process. Then, the transmissions of signal pass from Wernicke area to Broca area by the way of Arcuate fasciculus. Then, there is the activation of skilled motor programs in broca area to control word formation and transmission of appropriate signals to motor cortex to control speech muscle. This pathway is carried out by the neurotransmitters involved in this current communication. These neurotransmitters may be represented as buddhi vaisheshika pitta. The pathway for chakshyu vaisheshika pitta and buddhi vaisheshika pitta is explained in [Figure 2].
The primary visual area (Area 17) detects the specific sensation of vision. After that the information passes to the secondary visual area to analyze the meaning of specific sensory signal such as interpretation of color, light intensity, direction of lines and angles, and other aspects of vision. The association area receives and analyzes the signal from sensory cortices, motor cortices as well as subcortical structures for change in behavior, higher intellect as well as desired motor action.
Buddhi vaisheshika pitta, a type of Alochaka pitta, provides knowledge regarding past experience and differentiate the things from each other to compare with previous experience. It also stores the information for future use. Buddhi vaisheshika pitta acts at the molecular level to communicate between the cortical and subcortical structure of the brain for which there is happening of differentiation, comparison, or remembrance of knowledge. Buddhi visheshika pitta performs its function even after the formation of buddhi and smriti. The lower brain center initiates the wakefulness in the cerebral cortex and open its bank of memory for the generation of buddhi. Buddhi and smriti are required for the high level of interpretative meaning of the sensory information.
Differentiation, comparison, or remembrance of knowledge requires a possible mechanism of thought and memory. All the sensory information passes to the sensory cortex through three pathways. There are three major primary sensory areas in the cerebral cortex. Those are primary somatic area, primary visual area, and primary auditory area which detects the specific sensory information from the peripheral sensory organ. Then, the information goes to the secondary sensory areas which make sense out of the signal. The secondary sensory areas analyze the meaning of the sensory signal. The secondary somatic area helps in interpretation of the shape or texture of an object in one's hand. The secondary visual area helps in interpretation of color, light intensity, directions of lines and angles, and other aspects of vision. The secondary auditory area helps in the interpretation of the meaning of sound tone and sequence of tones in the auditory signals.
There are three association areas present in the cerebral cortex that receive and analyze the signals simultaneously from the multiple regions of both the motor and sensory cortices as well as subcortical structures. The important association areas include
- Parieto-occipito-temporal association areas
- Prefrontal association area
- Limbic association area.
- Parieto-occipito-temporal association areas provide a high level of interpretative meaning for signals from all the surrounding sensory areas. It has some functional subarea.
- Analysis of spatial coordinates of the body-this area receives visual sensory information from the posterior occipital cortex and simultaneous somatosensory information from the anterior parietal cortex. From all this information, it computes the coordinates of the visual, auditory, and body surroundings
- Wernicke area is important for language comprehension. It is the most important region of the entire brain for higher intellectual function
- Angular gyrus area is needed for initial processing of visual language (reading). It is needed to make meaning out of the visually perceived words
- Area for naming objects: the names are learned through the auditory input, whereas physical natures of the object are learned mainly through the visual input.
Prefrontal association area receives much preanalyzed sensory information especially information from the spatial coordinates of the body through subcortical bundle of nerve fibers. The prefrontal association area is essential to carrying out thought process. It also stores working memories that are used to combine new thoughts while they are entering the brain. That's why the prefrontal cortex is called as the locus of higher intellect in the human beingLimbic association area is concerned primarily with behavior, emotion, and motivation. It provides emotional drives for activating other areas of the brain and motivational drives for the process of learning itself.
The mechanism explained above is the production of buddhi, smriti. Only a small fraction of sensory information causes immediate motor response, but most of the information is stored for the future control of motor activities and for use in the thinking process. All the information is stored in the cerebral cortex, basal region of the brain, and spinal cord. The storage of information is a process called memory. Once memories have been stored in the nervous system, they become the part of brain processing mechanism for future thinking.
Buddhi vaisheshika pitta provides knowledge regarding past experience and differentiate the things from each other to compare with previous experience. It also stores the information for future use. Without the generation of buddhi and smriti, thought process is impossible. Buddhi vaisheshika pitta cannot perform its own functions. Hence, the neurotransmitter responsible for the mechanism of buddhi and smriti may be recognized as buddhi vaisheshika pitta at the molecular level. Buddhi vaisheshika pitta helps in generation of buddhi. The pathway for buddhi generation by buddhi vaisheshika pitta is mentioned in [Figure 3].
|Figure 3: Generation of buddhi for the function of buddhi vaisheshika pitta|
Click here to view
There are multiple neurohormonal systems present in the brain. Activation of each of the systems plays its own role in controlling the different quality of brain function. Some of the important neurohormonal systems are given below.
- Locus ceruleus and the norpeinephrine system
- The substantia nigra and dopamine system
- The raphe nuclei and serotonin system
- The gigantocellular neurons of the reticular excitatory area and acetylcholine system.
In addition to these neurotransmitters, other neurohormaonal substances that are secreted in the brain are enkephalins, gamma-aminobutyric acid, glutamate, vasopressin, adrenocorticotropic hormone, alpha-melanocyte-stimulating hormone, neuropeptide-Y, epinephrine, histamine, endorphins, angiotensin-2, and neurotensin. Activation of all these multiple neurohormonal systems in the brain plays an important role in controlling the different quality of the brain. All these neurotransmitters that help in communication between the cortical and subcortical parts of the brain responsible for thoughts and memory may be represented as buddhi vaisheshika pitta. Chemicals having same functions of Chakshyu vaisheshika pitta and buddhi vaisheshika pitta is explained in [Table 2].
| Discussion|| |
In previous studies, the only conceptual study of Alochaka pitta in Ayurved is mentioned. There are no studies done regarding the correlation between the functions of Alochaka pitta and modern perspective. Vata, pitta, and kapha dosha are responsible for homeostasis of the human body. Pitta doshas are liquid in nature, may be represented as enzyme, hormone, and neurotransmitter. Energy-producing substances also mediate chemical reactions. Pitta dosha also plays a major role in neurotransmission. It is due to the properties of and pitta such as teekshna, ushma, drava, and sara. Pitta dosha is of five types, namely Pachaka, Ranjaka, Alochaka, Sadhaka, and Bhrajaka. The site of Alochaka pitta is netra (eye) and its only function is visual perception without interpretation. In modern science, the pathway between rods and cones to the visual cortex is called as the optic pathway.
Based on the functions of Alochaka pitta, we can identify a variety of chemical factors, based on contemporary modern medical sciences responsible for the same functions. The chemical factors are none other than the photochemicals, enzymes, and neurotransmitters in the optic nerve pathway for vision. Rhodopsin, iodopsin, bathorhodopsin, lumirhodopsin, metarhodopsin-1, Metarhodopsin-2, isomerase enzyme, and the neurotransmitter responsible for communication in the optic pathway may be represented as Alochaka pitta.
Acharya Bhela has classified Alochaka pitta into two types. Chakshyu vaisheshika and buddhi vaishehsika. Chakshyu vaisheshika pitta helps in the perception of visual images obtained from the present surroundings, whereas Buddhi vaisheshika pitta helps in analyzing the received information, generating thoughts, create ambition, and determining reaction.
Chakshyu vaisheshika pitta may be considered as the neurotransmitters involved in the optic pathway, represent alochaka pitta. Buddhi vaisheshika pitta may be represented as the neurotransmitter responsible for communication between the visual cortex association area, motor cortex, and subcortical region. Again the neurotransmitter that is responsible for communication between the association area of cerebral cortex, sensory cortices, motor cortices and subcortical part such as thalamus, limbic system, reticular formation of the brain for generation of thoughts, memory, and knowledge.
| Inadequacy|| |
Across all Ayurvedic textbooks, the following inadequacy is found in relation to Alochaka pitta.
Scholars of Ayurveda have mentioned the site of Alochaka pitta as antah taraka (Retina). It seems visual image is perceived in the visual cortex. If there is any lesion in the visual pathway in spite of intact retina, there may be loss of vision. Hence, on the basis of functions of Alochaka pitta, it is more appropriate to consider the site of Alochaka pitta in the visual pathway including the retina.
| Conclusion|| |
In this literary study, we collected various data from the Ayurvedic classics with the available commentaries, as well as the textbooks of modern medical sciences, various articles for better understanding of the concept of Alochaka pitta and its comparison with contemporary science. Ayurveda is a science based on functional understandings. In general, pitta is drava (liquid) in nature and involved in digestion, metabolism, biochemical reactions, chemical messengers at every level in the human body. It is due to its teekshna, ushma, and sara properties. Alochaka pitta is situated in netra. It is responsible for roopalochana (perception of vision). On the basis of functional understanding, the photosensitive chemicals in the eye called photopigment and the whole chemical processes involved in the photochemistry of vision, neurotransmitters involved in visual pathway from the retina to the visual cortex may be represented as Alochaka pitta. There is a need of further research to evaluate in detail all other doshas. Hence, that student of BAMS can understand easily the basic concepts of doshas.
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[Figure 1], [Figure 2], [Figure 3]
[Table 1], [Table 2]