ūrdhvaṁ gachchhanti sattva-sthā madhye tiṣhṭhanti rājasāḥ
jaghanya-guṇa-vṛitti-sthā adho gachchhanti tāmasāḥ || 18||

My Understanding : The three gunas are reflected in the human spinal cord, with each part symbolizing different qualities and aspects of life. The upper part of the spinal cord represents the microcosm of purity, peace, knowledge, and goodness—qualities associated with Satvaguna. People influenced by Satvaguna are free from attachments like love and hate. They view life from various perspectives, recognizing the inherent goodness in nature and the world around them. They embody tranquility and wisdom, seeking clarity in all situations. The portion of the spinal cord around the navel is associated with Rajoguna, which governs emotions such as love, hate, and the results of one’s actions (karma). Rajoguna individuals are often driven by the desire for outcomes, seeking rewards for their efforts. This attachment to results can lead them to face sorrow and dissatisfaction in life, as their actions are motivated by external expectations rather than inner peace. The lower part of the spinal cord is linked to the senses and represents Tamoguna. People influenced by Tamoguna are drawn to physical desires, including food and sensual pleasures, and may struggle with lust. Tamoguna individuals may also experience sluggishness or lethargy, often manifesting as excessive weight or a lack of energy. In the hierarchy of the gunas, Satvaguna occupies the highest position, representing purity and wisdom. Rajoguna is in the middle, marked by desire and attachment to outcomes, while Tamoguna is at the lowest, representing ignorance and sensual attachments.