STRUCTURAL ASPECT OF FIVE SENSORY ORGANS

STRUCTURAL ASPECT OF FIVE SENSORY ORGANS

The five Jnana Indriyas or sensory organs—Chakshu (Eye), Shrotra (Ear), Ghrana (Nose), Rasana (Tongue), and Sparshana (Skin)—are responsible for perception of respective stimuli. Their anatomical structure is detailed both in classical Ayurvedic texts and modern human anatomy. In Rachana Shareera, these are understood as Indriya Adhisthana or structural bases of perception.

CLASSICAL CONCEPT OF INDRIYA STHANA
According to Ayurveda, each sensory organ (Jnana Indriya) has a specific Indriya Sthana, where the function of perception manifests.

🔸 चक्षुर्बुद्धेः प्रवृत्तिस्थानं नेत्रं स्याच्चाक्षुषं च तत्।
श्रोत्रं श्रोत्रेन्द्रियस्योक्तं नासिका घ्राणगोचरम्॥
(Charaka Samhita)

🔸 रसना रसनस्योक्ता त्वक्च स्पर्शेन्द्रियं स्मृतम्।
तेषां प्रवृत्तिस्थानानि स्थानभूतानि चोच्यते॥
(Charaka Samhita)

CHAKSHUR INDRIYA (EYE)

AYURVEDIC VIEW

• Sthana: Akshi (Netra)

• Indriya Dravya: Tejomahabhuta predominant

• Adhisthana: Netra, Alochaka Pitta

• Upadhatu involved: Raktadhatu

• Chakshu functions through the Tejas principle.

MODERN ANATOMY CORRELATION

• Eyeball is the main organ; it lies in the orbit, protected by eyelids and cushioned by orbital fat.

• Three layers of eyeball:

  • Fibrous coat: Sclera and Cornea

  • Vascular coat: Choroid, Ciliary body, Iris

  • Nervous coat: Retina (contains rods and cones)

• Lens: Transparent biconvex structure focusing light on retina

• Accessory structures: Lacrimal apparatus, extraocular muscles

• Nerve supply: Optic nerve (cranial nerve II)

SHROTRA INDRIYA (EAR)

AYURVEDIC VIEW

• Sthana: Karnayugala

• Indriya Dravya: Akasha Mahabhuta predominant

• Adhisthana: Shrotra and associated structures

• Pravritti: Perception of sound through Shabda Guna

MODERN ANATOMY CORRELATION

• Divided into External ear, Middle ear, and Inner ear

• External ear: Pinna and external auditory canal

• Middle ear: Tympanic membrane and auditory ossicles (malleus, incus, stapes)

• Inner ear: Bony and membranous labyrinth

  • Cochlea: For hearing

  • Vestibular apparatus: For balance

• Eustachian tube: Maintains pressure

• Nerve supply: Vestibulocochlear nerve (cranial nerve VIII)

GHRAANA INDRIYA (NOSE)

AYURVEDIC VIEW

• Sthana: Nasa

• Indriya Dravya: Prithvi Mahabhuta predominant

• Adhisthana: Nasa, Olfactory structures

• Pravritti: Perception of Gandha (smell)

MODERN ANATOMY CORRELATION

• External nose: Formed by bones and cartilage

• Nasal cavity: Divided by nasal septum

• Conchae and Meatuses: Create turbulence in air

• Olfactory region: Located in upper part of nasal cavity

• Olfactory epithelium: Contains olfactory receptor cells

• Paranasal sinuses: Help in resonance and mucus drainage

• Nerve supply: Olfactory nerve (cranial nerve I)

RASANA INDRIYA (TONGUE)

AYURVEDIC VIEW

• Sthana: Jihva

• Indriya Dravya: Jala Mahabhuta predominant

• Adhisthana: Rasana, Jihva

• Pravritti: Perception of Rasa (taste)

MODERN ANATOMY CORRELATION

• Tongue: Muscular organ occupying floor of mouth

• Parts: Root, body, apex

• Papillae:

  • Fungiform, Circumvallate, Foliate, Filiform

  • Taste buds mostly in fungiform and circumvallate

• Five basic tastes: Sweet, salty, sour, bitter, umami

• Nerve supply:

  • Anterior 2/3: Chorda tympani (branch of facial nerve VII)

  • Posterior 1/3: Glossopharyngeal nerve (IX)

  • Root: Vagus nerve (X)

SPARSHANA INDRIYA (SKIN)

AYURVEDIC VIEW

• Sthana: Tvak

• Indriya Dravya: Vayu Mahabhuta predominant

• Adhisthana: Entire skin

• Pravritti: Perception of Sparsha (touch), also related to Vata dosha

MODERN ANATOMY CORRELATION

• Skin layers:

  • Epidermis: Outer, non-vascular

  • Dermis: Contains nerve endings, vessels, glands

  • Hypodermis: Fat and connective tissue

• Receptors for touch:

  • Meissner’s corpuscles: Light touch

  • Pacinian corpuscles: Pressure and vibration

  • Merkel’s discs: Texture

  • Free nerve endings: Pain and temperature

• Widespread distribution across the body

• Nerve supply: Various peripheral nerves (from spinal and cranial nerves)