The medieval cell doctrine: Foundations, development, evolution, and graphic representations in printed books from 1490 to 1630.

The medieval cell doctrine was a series of related psychological models based on ancient Greco-Roman ideas in which cognitive faculties were assigned to "cells," typically corresponding to the cerebral ventricles. During Late Antiquity and continuing during the Early Middle Ages, Christian philosophers attempted to reinterpret Aristotle's , along with later modifications by Herophilos and Galen, in a manner consistent with religious doctrine. The resulting medieval cell doctrine was formulated by the fathers of the early Christian Church in the fourth and fifth centuries. Printed images of the doctrine that appeared in medical, philosophical, and religious works, beginning with "graphic incunabula" at the end of the fifteenth century, extended and evolved a manuscript tradition that had been in place since at least the eleventh century. Some of these early psychological models just pigeonholed the various cognitive faculties in different non-overlapping bins within the brain (albeit without any clinicopathologic evidence supporting such localizations), while others specifically promoted or implied a linear sequence of events, resembling the process of digestion. By the sixteenth century, printed images of the doctrine were usually linear three-cell versions with few exceptions having four or five cells. Despite direct challenges by Massa and Vesalius in the sixteenth century, and Willis in the seventeenth century, the doctrine saw its most elaborate formulations in the late-sixteenth and early-seventeenth centuries with illustrations by the Paracelsan physicians Bacci and Fludd. Overthrow of the doctrine had to await abandonment of Galenic cardiovascular physiology from the late-seventeenth to early-eighteenth centuries.