How was Usher changed?

From the text:

The now ghastly pallor of the skin, and the now miraculous lustre of the eye, above all things startled and even awed me. The silken hair, too, had been suffered to grow all unheeded, and as, in its wild gossamer texture, it floated rather than fell about the face, I could not, even with effort, connect its Arabesque expression with any idea of simple humanity.