The Brain Determines the Strength of Consciousness Function

What is the difference between isolated mental consciousness in dreams and that outside of dreams? During sleep, the circulation of qi and blood weakens, and consequently, the circulation in the brain also diminishes. The six consciousnesses rely on the subtle sense faculties within the brain to arise and function. After isolated mental consciousness arises in a dream, due to issues with the subtle sense faculties, the functions of mental consciousness become relatively weak. As a result, the discernment of mental consciousness within the dream is not clear or detailed, and memories formed are not solid. If the mental faculty deems the dream particularly important or highly stimulating, the impression becomes profound, causing the isolated mental consciousness to deepen its imprint. Upon awakening, mental consciousness can then recall the dream vividly and clearly.

Due to external factors causing brain injury that results in coma, the six consciousnesses vanish. After regaining consciousness, some individuals may experience amnesia. This occurs because the brain damage obstructs the functioning of mental consciousness, leading to disruption or weakening of its ability to integrate information. Consequently, it becomes impossible to recall people or events from a certain period. However, if the brain is subjected to strong stimulation, mental consciousness may recover those memories, bringing back past people and events. Memories from childhood and infancy are often unstable precisely because the brain is not fully developed, resulting in weaker mental consciousness function and less solid memories. In the elderly, mental consciousness generally functions less effectively than in youth, leading to less detailed discernment, coarser mental processing, and what is commonly referred to as senility.

Impaired circulation of qi and blood can damage the brain, causing a person to become foolish, dull, or mentally impaired. Therefore, the six consciousnesses are dependently originated phenomena, conditioned dharmas, utterly illusory and unreliable. They are neither the self nor belonging to the self. In the intermediate state (bardo), the functional capacity of mental consciousness is even weaker because the bardo body is temporarily arisen, composed of coarse and inferior four elements, far inferior to a human body, severely hindering the functioning of mental consciousness. Consequently, within the bardo, mental activities are primarily governed by the mental faculty, and mental consciousness cannot effectively regulate the mental faculty. The inherent nature of the mental faculty then determines the direction of future rebirth. Therefore, attainments realized solely by mental consciousness are like paper-made fruition. Only when the mental faculty simultaneously attains the fruition will the realization be solid and unretreatable, carried forward into future lives.