From time immemorial artistic insights have been revealed to artists in their sleep and in dreams, so that at all times they ardently desired them. Then their imagination could work wonders upon wonders and invoke the shades of the philosophers, who would instruct them in their art. Today this still happens again and again, but most of what transpires is forgotten.. How often does a man say as he wakes in the morning, "I had a wonderful dream last night," and relate how Mercury or this or that philosopher appeared to him in person and taught him this or that art. But then the dream escapes him and he cannot remember it. However, anyone to whom this happens should not leave his room upon awakening, should speak to no-one, but remain alone and sober until everything comes back to him, and he recalls the dream.-Paracelsus, "Spagyrical Writings"
Dreaming has been characterized as “single-minded” . In waking consciousness, we usually are able to reflect on, compare, or recall experiences, or thoughts, apart from the current one we are experiencing. It is not that these processes are completely excluded during dreaming - a counter-example is lucid-dreaming. It is rather that they are massively attenuated so that dreaming is “isolated” from other capacities or functions of consciousness. One finds a similar inability to transcend one’s current perspective, to reflect on, monitor or consider alternative views in acute psychosis of schizophrenia. As in dreaming, one is trapped in the “now” [2,18,19]. Kafka’s stories and novels often depict this sort of single mindedness which we find in dreaming. For example, the sudden appearance of the unexpected or bizarre is met with the protagonist’s blasé acceptance as matter of course. In his novel, The Castle, Kafka describes his protagonist, K., as taking the unexpected as matter of course: “The particular instance surprised K., but on the whole he had really expected it” , p. 5.- Mishara, "Philosophy, Ethics, and Humanities in Medicine<"
Kafka deliberately scheduled his writing during the night in a sleep-deprived state. It is also known that he drew from hypnagogic imagery in his stories . In his Diaries, Kafka describes his nocturnal writing as conducted “entirely in darkness, deep in his workshop” , p. 518; see also . As Kafka reports, writing without sleep enables access to unusual thoughts and associations which otherwise would be inaccessible: “How easily everything can be said as if a great fire had been prepared for all these things in which the strangest thoughts emerge and again disappear” , pp. 293-4, my translation). With regard to this transformed state of consciousness, he writes, “all I possess are certain powers which, at a depth almost inaccessible at normal conditions, shape themselves into literature...” , p. 270.” Similarly, Kafka writes in his Diaries, “Again it was the power of my dreams, shining forth into wakefulness even before I fall asleep, which did not let me sleep... I feel shaken to the core of my being and can get out of myself whatever I desire. It is a matter of ... mysterious powers...” (cited by Corngold, , p. 23). Sleep deprivation may serve as a non-drug “psychotomimetic” model (i.e., producing a psychotic like state in healthy individuals) with attendant changes in dopamine in the striatum and NMDA and AMPA ionotropic glutamate receptorfunction in pre-frontal cortex . Indirectly, this suggests a possible relationship between intrusive hypnagogic imagery (which is increased with sleep deprivation) and the experiences of beginning psychosis , and below.
Kafka’s “great fire” suggests a creative process which provides its own illumination even in darkness. It also suggests a state of cortical excitability (and resulting hypnagogic hallucinations) following Kafka’s withdrawal from sensory/social stimuli coupled with sleep deprivation. Kafka longs for “complete stillness” (as Gregor in The Metamorphosis) eager to separate himself, while writing, from his argumentative family with whom he lived for a good part of his life.xix The Hunger Artist “withdraws deep within himself paying no attention to anyone or anything” , p. 268. Kafka is avoidant of unnecessary stimulation, which may also be prompted by his severe headaches , and sleeplessness , p. 231. However, the withdrawal from photic and social stimulation is also prerequisite for the self-induction of hypnagogic-like trances.
Kafka marveled at the automaticity of his own writing. In a letter to his future betrothed, Felice Bauer - whom he persistently tries to discourage, as evidenced by this letter, from wanting to marry him - Kafka writes: “I have often thought that the best mode of life for me would be to sit in the innermost room of a spacious locked cellar with my writing things and a lamp. Food would be brought and always put down ... outside the cellar’s outermost door. ... And how I would write! From the depths I would drag it up! Without effort! For extreme concentration knows no effort” , p. 156). Here we find solitude, the reduction of sensory stimulation in the cell’s darkness, and the automaticity (effortlessness) of the writing process. According to Kafka’s own reports, he experienced writing (at least in its initial phases) as automatic, effortless and informed by hypnagogic imagery.xxx When writing is effortless, it is the product of a trance-state called “flow” shown to facilitate optimal mental functioning (Csikszentmihalyi, ). Kafka writes, “All I possess are certain powers which, at a depth inaccessible under normal conditions, shape themselves into literature...” , p. 270). In a letter to Max Brod, Kafka  writes that it is “not alertness but self-oblivion [that] is the precondition of writing” (p. 385).