"what mistaken notion about the nervous system persisted from ancient times up through the work of some renaissance thinkers? "

A common mistaken notion about the nervous system that persisted from ancient times up through the work of some renaissance thinkers was that the ventricles play a major role in the transmission of messages in the brain. In actuality the ventricles are filled with cerebrospinal fluid (CSF) which bathe and cushion the brain and spinal cord within their bony confines, thus protecting them, amongst other things.

Where is the picture at