States of consciousness occurring between wakefulness and sleep—such as lucid dreaming, hypnagogic hallucinations, and sleep paralysis—are formally recognized and classified in scientific literature as distinct experiential and physiological phenomena.
The retrieved papers consistently discuss intermediate states between waking and sleeping (such as lucid dreaming, hypnagogic hallucinations, and sleep paralysis) as recognized, distinct physiological and phenomenological phenomena studied in cognitive neuroscience and sleep medicine. Therefore, the claim is well-supported by the literature.