We appreciate the interest in our paper, and the additive comments from Drs. Tan and Li.

They have offered important points; we agree with all of them, and are grateful for their additions.

Our experience too, confirms the great benefit to patients of learning that they are not mad, and that the hallucinations can vary, or clear.

Despite the large volume of verbiage on this old (but recently fashionable) topic, the neural mechanism remains obscure. We anticipate that improved functional brain imaging will demonstrate pertinent CNS pathways and bring CBS modifying agents. Better than that of course, any improved visual function, where possible, as in this case, can be remarkably rewarding to patients and physicians.