In dreams, is there discrimination by the five consciousnesses?

The realms experienced in dreams are all subjectively imagined realms, all mental sense-object (dharma-viṣaya) realms; there are no relatively more real real-form five sense-objects. Because the five sense-objects are lacking, the subjectively imagined realm is incomplete and deficient, and the mental objects discriminated by the solitary consciousness (mano-vijñāna-eka-citta) alone are not very clear—they are approximate, extremely illusory and unreal. Therefore the mind consciousness and the manas cannot discriminate very clearly, and mistakes are inevitable; sometimes there are especially many and especially great errors, often mistaking one thing for another. In dreams, discrimination by the manas is dominant; the manas has weak discriminating wisdom toward unfamiliar realms and lacks accurate judgment, so what it discriminates is unclear and indistinct.

If there were five sense-object realms in a dream, the five consciousnesses would participate in the discrimination, and then it would be no different from being awake—there would be no dream state and no sleep.