Majja Dhatu: Bone Marrow, Nervous Tissue
Something I was listening to recently mentioned the Ayurvedic understanding of the nervous system, or nervous tissue, being connected to bone marrow (Majja Dhatu). This reminded me of the Ayurvedic understanding of the seven systems, refined layers of fluid and matter, the substance that constitutes the human body, and got me curious to find out more about the Ayurvedic understanding of the nervous system.
Most of what I have learned about the nervous system over the past few years has been from modern Western psychology, psychotherapy and science. It was nice to be reminded of the wisdom of Ayurveda, and to research the history of our understanding of the nervous system.
Ayurveda dates back to the Vedic period over 3,000 years ago and is a holistic system of medicine focused on creating harmony in the body to prevent disease.
The origin of Ayurveda is considered to be divine, from the Hindu God, Brahma, who is called the creator of the universe. It is believed that the creator of the universe passed on this holistic knowledge of healing onto the sages for the well-being of mankind (Jaiswal YS, Williams LL, 2016)
Ayurveda is officially classified as an Upaveda, something like a supplementary Veda. The oral traditions of the Vedic period were eventually codified into medical texts, the most important being the Charaka Samhita and Sushruta Samhita, which were compiled between 1500 BCE and 500 CE.
In Ayurveda, the nervous tissue is one layer of the system of seven layers of increasingly refined tissue, the Saptadhatus. The word sapta means seven, and dhatu means ‘that which holds,’ ‘building block,’ or root. In Sanskrit grammar, a dhatu is the fundamental verbal root of the language. It is the core, unchanging syllable or word from which nouns, verbs, and adjectives are derived. In Ayurveda, dhatus refer to the seven fundamental layers of tissue that sustain and physically hold the human body together. They are the pillars of the body, providing nourishment, growth and structure, and are understood as a sequence. Each dhatu receives nourishment from the one before, each one arising from the transformation of the last as the source of vitality moves deeper and deeper into the interior of the living system. Therefore, when one dhatu is imbalanced, it will have a knock-on effect deeper into the body.
The Saptadhatus:
1. Rasa Dhatu Plasma / Lymph: Rasa corresponds to the lymphatic and circulatory plasma systems, the most fluid, mobile layer of the body.
2. Rakta Dhatu - Blood: Rakta carries oxygen, nutrients, and hormones throughout the body and is considered jeevan, life itself. It corresponds broadly to the blood and its oxygen-carrying function.
3. Mamsa Dhatu - Muscle Tissue: Mamsa represents muscle tissue, providing strength and movement, everything that gives the body its capacity to act in the world.
4. Meda Dhatu - Fat / Adipose Tissue: Meda corresponds to fatty tissues, thermal insulation, organ protection, tissue lubrication, the joints and the moisture held within them. Psychologically, Meda is associated with softness, groundedness, and the capacity to feel held and resourced.
5. Asthi Dhatu - Bone & Cartilage: Asthi represents the bones, structure and support, the teeth, nails, and hair. Persistent fear is said to weaken Asthi, in alignment with modern research on the relationship between chronic stress, cortisol, and bone density.
6. Majja Dhatu - Bone Marrow & Nervous Tissue: Majja is associated with the nervous system, brain, and spinal cord. The nervous system and bone marrow are treated as homologous structures in Ayurveda. It governs the central and peripheral nervous systems, the transmission of impulse and sensation, memory, and the deep interior life of the body. Chronic stress is said to impact Majja directly.
7. Shukra Dhatu - Reproductive Tissue / Creative Essence: Shukra is the most refined essence of all seven dhatus, responsible for reproduction, creativity, and vitality. In women it is sometimes referred to as artava and is associated with the ovum and reproductive fluids. Shukra is understood as the distillation of all the other six dhatus, the most subtle and precious expression of the whole system.
This seven-layer system works in a movement direction of refinement from gross to subtle. From the peripheral boundaries and fluids, nourishment moves inward through the layers to the reproductive creative essence.
There is a beautiful psychological dimension layered through each dhatu. In Ayurveda, chronic fear is understood to disturb Vata and enter the bones; grief affects digestion and depletes the body’s most fluid layers; and chronic stress reaches all the way into Majja, effectively drying out the nervous system and withdrawing nourishment from deep within the body. The body is understood as a living record of everything we have experienced and felt. There are many references in the classical texts to the psychological dimensions of the dhatus, and depletion of these layers.
According to the Charaka Samhita (Vimana Sthana 2/9), food taken in proper quantities and even foods that are compatible do not get digested due to emotions like worry (Chinta), grief (Shoka), fear (Bhaya), and anger (Krodha). (Sharma & Dash, 1977) This is important because in Ayurveda, if food cannot be digested, the dhatus cannot be nourished. This means that emotion, in the classical understanding, directly interrupts the chain of tissue formation. Undigested experience becomes Ama, which is accumulated toxic residue in the tissues.
We find in the Charaka Samhita (Chikitsa Sthana 28) a reference to Chinta Shoka karshana (a weakening of the body tissues due to excessive stress, grief, and worry) as a direct cause of dhatu depletion (Sharma & Dash, 1977). In the Charaka Samhita (Sutra Sthana 17), Shoka or grief, is listed as a direct cause of Vata-type heart disease, producing symptoms like trembling, stiffness, and darkness (Sharma & Dash, 1977). In Ayurveda, the heart is regarded as the seat of Ojas and Rasa, the most fluid and nourishing layer of the body. When we are affected by grief, it is understood to be entering the Rasa Dhatu directly. Ojas is viewed as being the refined essence of all seven dhatus. When grief depletes Ojas, it is effectively grief reaching into every layer of the body simultaneously.
The Ashtanga Hridayam (Sutra Sthana 11/26) states that Vata dosha ‘lives in’ and is connected to the bones (Asthi Dhatu). Fear and anxiety are understood as the psychological expressions of aggravated Vata, which explains the classical understanding that chronic fear enters and disturbs the bone tissue.
My particular interest at the moment is Majja, the sixth layer of the seven-layer system. In the Ayurvedic understanding, bone marrow, the brain, the spinal cord, and the nervous system are not separate systems but homologous structures all gathered under the dhatu of Majja, all expressions of the same deep, nourishing intelligence of the interior body. We now know from the study of embryology that the nervous system develops from the ectoderm and that bone marrow develops from the mesoderm.
The Ayurvedic perspective views Majja dhatu as the soft, deeply nourishing tissue that includes both bone marrow and the nervous system (brain, spinal cord, and nerve tissue). Just as bone marrow is protected within the hard casing of bone, the delicate nervous tissue is safeguarded by the vertebrae and skull. The understanding is that Majja dhatu is a comprehensive tissue responsible for various physiological processes, structural support, and the transmission of messages through the nervous system.
One of the functions of Majja is snehana, which comes from the Sanskrit root snih, meaning "to be sticky" or "to bind." Figuratively, snehana denotes the emotional "stickiness" or binding nature of love and strong attachment. Sneha also refers to oil, grease, or unctuousness and is used to describe substances such as medicinal oils and ghee used in Ayurvedic therapeutic treatments. The function of snehana in relation to Majja is that it provides lubrication and unctuousness to the bone marrow and the nervous system, as well as physical strength and nourishment (bala) to the reproductive tissues. It brings warmth, smoothness, and stability to the subtle channels that carry sensation, memory, and intelligence. Through the unctuous quality of sneha, Majja dhatu supports the connection between body, mind, and emotional experience.
When Majja dhatu is healthy, it fosters a sense of fullness and completion, whereas a deficiency creates feelings of emptiness. This resonates with the somatic understanding of nervous system depletion and burnout, or scattered, ungrounded nervous system energy, which can be understood in Ayurveda as a depletion in Majja, often driven by excess Vata in the deep tissues. (one of the three doshas in Ayurveda)
The practices that restore Majja go deep to nourish the interior. Warm oil massage (abhyanga), deep nourishing foods, rest, reduction of sensory overload, and practices like Yoga Nidra. Yoga nidra is a practice of pratyahara, or sensory withdrawal, drawing awareness inwards to the deepest layers of our interior. The rotation of consciousness in Yoga Nidra, moving through the body limb by limb, part by part, could be seen as a form of snehana, a loving, oiling of the nervous web from within.
I was curious to find out how different systems of traditional medicine understood the nervous system, and there seems to be a common understanding of a living transmission network running through the body, subtler than blood, and that the health of the whole organism relies on this network being open and nourished.
The West
The ancient Egyptians regarded the heart as the centre of intelligence; the brain was considered unimportant. The heart was carefully preserved during mummification, whereas the brain was removed. However, there is a very thorough systematic study of injuries from the head down to the spine recorded in the Edwin Smith Papyrus, which contains descriptions of the meninges, the external surface of the brain, the cerebrospinal fluid, and intracranial pulsations. They accurately observed the nervous system in trauma without theorising about it as a system.
The heart vs. the brain as the centre of intelligence was argued by the Greeks. Alcmaeon of Croton (c. 500 BCE) was one of the first people to believe that the brain was the seat of intelligence and sensation, developing the idea that nerves (poroi) connected the brain to the body. Plato was a supporter of the encephalocentric model developed by Herophilus and Erasistratus of the Alexandrian school, who performed dissections and distinguished sensory from motor nerves. This model was rejected by Aristotle, who believed that the heart was the seat of sensation and that the brain was merely a cooling organ for the blood.
In the Roman era, Galen, an influential physician who dissected many cadavers, developed the idea that the brain and nerves were central to thought and movement. He concluded that the soft cerebrum stores memories, and the hard muscle of the cerebellum controls muscles. He also believed the ventricles of the brain were reservoirs for the bodily humours. Galen described the nerves as hollow tubes carrying "psychic pneuma" (a subtle life spirit) from the brain to the body. His work is an early precursor to the understanding of neural transmission.
The cardiocentric view in Europe persisted through medieval times and we still hear it today in phrases like "heartfelt," "heart and soul," and "with all my heart", all of which have their origin in the understanding that the heart was the seat of feeling and consciousness.
The East
The Indian traditions of understanding were founded on meditative inquiry into the body’s felt experience from within. According to their systems, pranic energy circulates through every living being through subtle channels called nadis, which follow a similar, but far more extensive path as the central nervous system. The three main nadis correlate to modern neuroanatomy, where we can align Ida and Pingala nadis to the left and right hemispheres of the brain, and Sushumna, the central channel, with the spinal cord and central channel of cerebrospinal fluid.
The unique insight of the yogic tradition is that the nervous system is both a carrier of information and a vehicle for consciousness itself. It follows that, through specific practices such as pranayama, asana, meditation, and Yoga Nidra, the quality and flow of awareness within this network can be intentionally refined.
Chinese medicine also developed extraordinarily detailed maps of the body's transmission network, identifying twelve primary meridian pathways through which qi, the vital life force, circulates. Each meridian line is associated with a specific organ system, and any disruption or blockage in the flow of qi can lead to illness. Modern research shows a relationship between the afferent nerve fibres activated during acupuncture and an integrated response across different levels of the central nervous system.
The Tibetan system of medicine combines elements of both Ayurveda and the Chinese system, and describes the five winds, or ‘lung’, similar to the prana vayus in Ayurveda, which govern different aspects of nervous function. Imbalanced lung, particularly the life-sustaining and all-pervading winds, produces precisely what we would now recognise as nervous system dysregulation: anxiety, insomnia, disconnection, and hypersensitivity.
What has changed over the years of this study is what we have believed the transmission to be. Humanity has long explored concepts of the animating force, life energy, consciousness, or spirit that enlivens living beings. These ideas map the same territory that modern neuroscience now describes as the vast, intricate web of electrochemical signals travelling through the axons of the nervous system.
Like the underground web of mycelium, a theme of a recent yoga nidra I recorded, the nervous system lives below the surface and both are systems of transmission, carrying nourishment, impulse, and intelligence through a living network. The traditional rotation of conciousness in yoga nidra lends itself well to the overlay of mycelium threads connecting up the whole body. Both the nervous system and mycelium require moisture, softness, and the absence of harsh conditions to function well. And both, when healthy, generate a felt sense of connection, fullness, and coherence, the quiet hum of a system that knows itself to be whole.
Jaiswal YS, Williams LL. A glimpse of Ayurveda - The forgotten history and principles of Indian traditional medicine. J Tradit Complement Med. 2016 Feb 28;7(1):50-53. doi: 10.1016/j.jtcme.2016.02.002. PMID: 28053888; PMCID: PMC5198827.
Murthy, K. R. S. (2012). Ashtanga hridayam: Text, English translation, notes, appendix and index (Vol. 1, 9th ed.). Krishnadas Academy.
Sharma, R. K., & Dash, B. (1977a). Charaka Samhita: Text with English translation and critical exposition based on Chakrapani Datta's Ayurveda Dipika: Vol. 2. Vimana Sthana (2nd ed.). Chowkhamba Sanskrit Series Office.