I think there's probably always been visions and voices, and these were variously ascribed to the divine or demonic or the muses. I think many poets still feel they depend on an inner voice, or a voice which tells them what to do.
Oliver SacksThe brain is more than an assemblage of autonomous modules, each crucial for a specific mental function. Every one of these functionally specialized areas must interact with dozens or hundreds of others, their total integration creating something like a vastly complicated orchestra with thousands of instruments, an orchestra that conducts itself, with an ever-changing score and repertoire.
Oliver SacksDangerously wellโโ what an irony is this: it expresses precisely the doubleness, the paradox, of feeling โtoo well
Oliver Sacks