In Miguel de Cervantes' "Don Quixote," the protagonist becomes a victim of excessive reading and insufficient sleep. His mind, overwhelmed by the countless tales of chivalry he consumes, begins to deteriorate. The impact of his obsession leads to a significant decline in his mental health, ultimately results in him losing his grip on reality.

This transformation highlights the dangers of losing oneself in fiction to the extent that it blurs the lines with reality. The story serves as a cautionary tale about the balance between imagination and sanity, emphasizing how escapism can lead to unforeseen consequences.