What object does Tokarczuk use in a metaphor characterizing the nocturnal brain and why?

In describing and analyzing the nocturnal brain, Tokarczuk uses vivid imagery and literary devices to make her point. In one passage, she states that the nocturnal brain is the "barcode of the world" (227). All day we receive information in the form of sensory input and at night, our brains read the gleaned information and process it like a computer.