The Six Consciousnesses in Sleep

In the state of the samādhi without perception (asaṃjñi-samāpatti) and in deep sleep, the six consciousnesses do not exist. If the mental activity of the six consciousnesses arises again, it is necessary for the manas to generate attention (manaskāra) and deliberation (manasikāra) toward the objects of the six sense-objects; only when there is a desire to discern the six sense-objects does the eighth consciousness give birth to the six consciousnesses to discern them, and thus one emerges from samādhi or wakes up.