Could it not be a pattern? Either a geometric pattern or a sequence pattern, like Morse code...? An image is the same image on a different screen; a code stays

Could it not be a pattern? Either a geometric pattern or a sequence pattern, like Morse code...? An image is the same image on a different screen; a code stays the same even if produced by different devices. In the article it seems the word "pattern" is used not in the sense of an actual pattern, ie a shape or design, independent of what produces it, but to indicate a specific group of neurons. For me (without knowing anything about it), I would think new sensory stimuli are encoded by "smart" neurons, and that gradually, as the stimuli is experienced again and again, less and less "smart" (or versatile, or performant) neurons are tasked with encoding it.