Reply to: Rethink the classical view of cerebrospinal fluid production.

The choroid plexus is generally agreed to be a key site of CSF production[4], although the relative contributions of choroid plexus in the lateral ventricle versus that in the fourth ventricle are uncertain and may differ between species. We agree that the questions of how much cerebrospinal fluid (CSF) is produced and from which structures remain unanswered. [Extracted from the article]