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A BRIEF HISTORICAL SKETCH –
THE STANDARD VIEW
It is commonly understood today that cogni-
tive functions such as language and memory
are not only located in the brain, they are local-
ized in different parts of the brain substance. In
fact, determining how and where cognitive
functions are located in the brain is one of the
major research objectives of modern neuro-
science. The question addressed in this chapter
is the history of this research: what were the
early models of functional localization, what
were the misconceptions, and when was the
more modern view first proposed?
A first glance at the history of cognitive
models of brain function gives the impres-
sion that the first effort was bizarrely erro-
neous: the ventricular theory of our medieval
forebears who claimed that cognition and
memory were located in the cerebral ventri-
cles, the fluid-filled interior spaces of the
brain. The roots of this model, which may be
characterized as ‘medieval cell doctrine and
ventricular theory’, go back to Aristotle’s
(384–322 BCE) views on cognition. Aristotle
believed that the five senses came together
in the head in a place called the sensus
communis, or common sensory input,
where mental images were created. These
images were in turn analyzed and manipu-
lated by cognitive processes and eventually
stored in memory. By the fifth century CE,
the early church fathers St Augustine and
Bishop Nemesius had assigned the compo-
nents of Aristotle’s cognitive model to the
cerebral ventricles. During the early Middle
Ages (sometimes called the ‘Dark Ages’),
Greek and Roman thought passed to the Arab
world; in the work of Avicenna (eleventh
century), medieval cell doctrine (MCD)
became the standard in medical practice.
Thanks to the plundering of Arab libraries
during the Crusades, MCD reappeared in
Europe around the twelfth century, by now
sufficiently established in the medical prac-
tice of the late Middle Ages and early
Renaissance that it was illustrated in a variety
of drawings as, for example, those shown in
Figures 4.1 (dated 1503) and 4.2 (dated 1506).
In addition to furnishing the standard
model of brain function, MCD became a
practical guide for early brain surgery and
was used to explain disorders of cognitive
CHAPTER
4
Was Medieval Cell Doctrine More
Modern Than We Thought?
H. Whitaker
Consciousness and Cognition
Edited by H. Cohen & B. Stemmer
ISBN-13: 978-0-12-373734-2 Copyright © 2007 Elsevier Ltd
ISBN-10: 0-12-373734-6 All rights of reproduction in any form reserved
Ch04-P373734.qxd 10/11/06 12:02 PM Page 45
functions due to brain disease, such as mem-
ory disorders. Although the great Renaissance
anatomist Andreas Vesalius (sixteenth cen-
tury) flatly rejected ventricular theory, based
upon his anatomical dissections, which
demonstrated no connections to sensory
organs or to skeletal musculature, vestiges
of MCD may be found all the way through
the seventeenth century. The majority of
historians of neuroscience currently believe
that brain models of functional localization
that more closely approximate our current
views, originated in the eighteenth century
in, for example, the work of Georg Prochaska
and Johann Unzer.
NEW VERSION – IT WAS IN THE
BRAIN ALL ALONG
The preceding is the standard view in the
history of neuroscience; however, recent work
by Ynez O’Neill of UCLA has considerably
modified our understanding of MCD and
ventricular theory. O’Neill has shown that,
since the twelfth century, there has been a
second version of MCD that localizes brain
functions to either the meninges or the cere-
bral cortex, instead of the presumed-empty
spaces of the cerebral ventricles. This is
important because it dates modern theories
of brain function about 600 years earlier
than is currently believed. Additionally, to
recognize a cortical localization variant of
MCD leads us to reinterpret many of the cell
diagram drawings of the twelfth to sixteenth
centuries and to reanalyze certain case reports
of functional impairments following brain
damage from this epoch.
O’Neill’s primary argument was based
upon the analysis of a twelfth century draw-
ing of the brain and eye shown in Figure 4.3,
46 4 WAS MEDIEVAL CELL DOCTRINE MORE MODERN THAN WE THOUGHT?
FIGURE 4.1 This 1503 drawing by an anatomist
from Bologna is a classic medieval cell diagram; the
brain functions are represented in three circles in the
forehead area (common sensory input and imagination),
just above the ear (fantasy and estimation), and at the
back of the head (memory and motion).
FIGURE 4.2 In this drawing from a 1506 version of
Albertus Magnus’s Philosophia pauperum (A Meager
Philosophy), the three ‘ventricles’ are identified about
the surface of the head. The author assumed that the
reader knew the brain functions well enough that it
was unnecessary to identify them (they are the same as
in Figure 4.1).
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which heretofore had defied analysis; she
demonstrated that it was a sketch based upon
a dissection procedure that exposed the cover-
ings of the brain – the dura mater, meninges
and pia mater – and, more importantly, placed
cognitive functions in those structures. Her
study provides convincing evidence that
there was a competing model to the ventric-
ular doctrine, a model that placed cognitive
functions squarely in the brain substance.
You can visualize this more readily by look-
ing at Figure 4.4, taken from Dryander’s
book of 1537; the brain coverings are marked
A, B, C, D, F, G, and the three oval-shaped
functional compartments, ‘VEN’; we shall
return to this figure in a moment.
EARLY STUDIES OF PATIENTS
WITH BRAIN DAMAGE
Even more convincing evidence that MCD
included a meningeal/cortical localization
comes from pre-Vesalian sixteenth-century
neuropsychological case reports, as these
EARLY STUDIES OF PATIENTS WITH BRAIN DAMAGE 47
FIGURE 4.3 Several figures like this one date
from the twelfth century and depict the brain and
its functions even more diagrammatically than the clas-
sic images in Figures 4.1 and 4.2. Here, the functions of
the third cell (memory and motion) are represented as
polyhedrons in the bar across the top of the picture. The
central dark vertical line represents the olfactory path-
way; the nose is at the bottom, between the two patterns
of concentric circles which represent the eyes. The optic
nerves are shown leading up toward a large chevron
shape, above which are represented structures and func-
tions such as the auditory nerve, reason, etc. The angle
of the chevron shape, the two channels leading from it
up to the bar at the top and the evident duplication of
the various polyhedrons on the left and right side of this
drawing, indicate how the functional cells in the
meninges would be displayed following standard dissec-
tion procedures of this period (O’Neill, 1993).
FIGURE 4.4 This Renaissance-style drawing is one
of the Johann Eichmann illustrations from 1537;
Eichmann was popularly known as Dryander. Sensory
input in this scheme goes not only to the first cell
(common sensory input) but also to the second, that is,
directly to fantasy and estimation. Motor control of
speech is nicely represented by lines numbered 6 and 7,
emanating from the movement part of the third cell
and going directly to the lips. Line number 4 and path-
way P represent motor control of the rest of the body.
The cross-hatching seen between the eyes is Galen’s
rete mirabile (‘wonderful net’), the point at which the
animal spirits were thought to change into the spirits
representing sensory images, memory, etc.
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translations from the Latin texts of Johannes
Schenck (1584) and Johannes Wepfer (1727)
indicate:
Hit by a terrible wound, a loss of memory
followed: one who received a severe
wound in his occipital bone and of both
meninges … which he lost together with a
part of the medullary substance and was
cured; but he completely lost his memory
(Amatus Lusitanus (1511–1561))
A wound of the brain with the cerebral sub-
stance coming out: We saw wondrous things
in patients with wounds of the brain. In one,
so much of the cerebral substance came out
from the wound, as was the size of a small
egg from a hen, but he survived … however,
he could not speak and he survived for three
years, inept and extremely stupid …
We then saw a soldier from Corsica … half
of his head had been fiercely removed by a
slash, together with the underlying part of
the brain; he recovered, but he could not
remember anything; he could not speak
and he was so much out of his mind, that
he could not understand or say anything
(Brassavola (1500–1555))
Also restored to health by my work is the
noble youth, Marcus Goro, who was
wounded by the sharp point of a halberd.
There was not only a fracture of the cranial
bone, but also a lesion of the meninges and
of the underlying brain tissue. Besides all his
other difficulties, the young man had been
speechless for eight days (Nicolas Massa
(1504–1589))
Figure 4.2 illustrates MCD in its bare-bones
(Aristotelian) outline; clearly, the model was
so well known in the late Middle Ages that it
was unnecessary to label the three ventricles.
The typical order of functions, beginning
from the front of the head (cf. Figure 4.1) was
sensus communis and variously fantasia or
imaginativa in the first compartment, cogita-
tiva and estimativa in the second, and mem-
orativa and motiva in the third. This
arrangement of the Aristotelian cognitive
functions is, of course, neutral with respect to
whether they were localized in the ventricles,
the meninges or the cerebral cortex.
A LITTLE LATIN TO HELP SORT
OUT THE PUZZLE
How modern historians of neuroscience
could have mistaken the localization question
likely hinges upon an ambiguity in the
Latin word ventriculus, as pointed out by
O’Neill. Expert translations of ventriculus in
a twelfth-century manuscript by William of
St Thierry used the term lobe, in a passage in
which William described how the animal
spirits facilitate cognitive function: (a) the
spirits pass to the rear lobe, there creating both
memory and motion and (b) each function
has its own home, a specific lobe (O’Neill,
p. 214). Thus, ventriculus, the diminutive of
venter (thus, ‘little belly, stomach or womb’)
can refer to the external ‘rounded bulge’ or
the internal ‘hollow space’.
Throughout the late Middle Ages, texts
discussing MCD and in drawings represent-
ing MCD employed both ventriculus and cel-
lula. The Latin cellula, the diminutive of cella
(thus, ‘small store-room, chamber or cabinet’)
is also ambiguous in a way analogous to ven-
triculus, referring to both an empty space and
an object. As a note added in proof, Galen
(first century CE) had placed cognitive func-
tions in the brain substance, not in the ventri-
cles and Galen was the principal if not sole
medical authority up to the sixteenth century.
One must conclude that a cortical and/or
meningeal localization doctrine competed
with, if not actually dominated, the ventricu-
lar localization doctrine throughout the
Middle Ages and early Renaissance.
INFORMATION FLOW – MAKING
THE MODEL DYNAMIC
In addition to the newly recognized evi-
dence that MCD actually placed functions in
the brain substance, another parallel with
modern theories of brain function and a fea-
ture that goes to the essence of contemporary
48 4 WAS MEDIEVAL CELL DOCTRINE MORE MODERN THAN WE THOUGHT?
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cognitive models, is the question of static
versus dynamic processing. From the time
of Classical and Hellenistic Greece, philoso-
phers thought that intangible substances –
animal spirits, aether or fluid – course
through the body and brain, accounting for
functions as diverse as digestion and mental
images. For Descartes, animal spirits flowed
through hollow nerves to engorge muscles
and thereby account for muscular con-
traction. For seventeenth- and eighteenth-
century scientists, the spirits, now ‘aether’,
could explain magnetism as well as sensation
and perception. For proponents of MCD, the
animal spirits formed a mental image by
input from the five senses, sensus communis
in the first ‘compartment’, employing the
function of fantasia or imaginativa. When an
internal image passed into the third com-
partment, memorativa stored it permanently.
As explained by William of St Thierry, rea-
son, or cogitativa and estimativa, located in
the second or middle compartment, differ-
entiated us from the beasts; it was here that
images could be combined into new, hereto-
fore not-experienced images, such as a uni-
corn, and it was from here that dreams
emerged. Figure 4.5 is a crudely drawn mid-
fourteenth-century illustration that captures
the information flow from cell to cell, using
the Avicennan version of MCD. Compare the
linkages between cells shown in Figure 4.5
to the absence of a pathway for mental
images to move about in Figure 4.4.
Information input was frequently repre-
sented in dynamic MCD models of brain
function – information output, less often. As
seen in Figure 4.5, auditory, visual, olfactory,
gustatory and – oddly placed in the throat –
tactile systems provide input to that part of
the first cell designated sensus communis,
the standard Aristotelian explanation for how
unified mental images are created. In Figure
4.4, we see lines representing motor output
emanating from the third cell, motiva (though
not named in this drawing, it is named in
Figure 4.1) to the lips and tongue to account
for speaking. There are additional lines that
descend down through the neck to account
for movement of the body, and yes, there is an
unexplained descending line coming from the
second cell; no one has claimed that our
medieval cartoonists were consistent. In
Figures 4.6 (drawing dated 1525) and 4.7
(drawing dated 1310), we see alternative ver-
sions of the information flow in MCD models;
in Figure 4.7, double lines as used in the ear-
lier Avicennan model are found, along with a
diagram of a worm, which in Latin is vermis,
showing the link between the last two cells. In
Figure 4.6, the word vermis suffices to show
the link between the first and second cell. It is
INFORMATION FLOW – MAKING THE MODEL DYNAMIC 49
FIGURE 4.5 A mid-fourteenth century treatise by
the great Arab physician, Avicenna, On Embryonic
Generation (De generatione embryonis), contains this
drawing, which is labeled ‘an anatomy of the head for
physicians’. Here the cells are actually designated as cells
(cellula) and information flow from one functional cen-
ter to the next is indicated with double lines. The five
senses (tactile, taste, smell, vision and hearing) all proj-
ect to the first functional cell, conventionally the com-
mon sensory input. The remaining four cells across the top
of the head are fantasy, imagination, cognition and memory.
Motor output is not represented in this diagram.
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exceedingly curious that our medieval fore-
bears used the term ‘worm’ to describe a pas-
sage between the ventricles. It has been
speculated that someone (perhaps Galen?)
noticed the choroid plexus on the surface of the
lateral cerebral ventricles and, consistent with
the ancient practice of naming anatomical
structures for their appearance, decided
that they looked worm-like. We now know
that the choroid plexus is one of the organs that
manufactures cerebrospinal fluid. Who first
suggested that the worm-like choroid plexus
provided a passageway between the ventri-
cles is unknown but it is clear that such a view
was incorporated into MCD by the thirteenth
century. Vermis was a feature of dynamic
models of MCD throughout this epoch.
THE BRAIN’S CONTROL OF
MOVEMENT
How did motor output come to be associ-
ated with the same cell in which memory was
located? Areasonable argument is the follow-
ing: Greek and Roman authors had sug-
gested that storing mental images was
literally like making an impression in wax,
which therefore required a softer brain sub-
stance. In contrast, a harder brain substance
would be the natural substrate to control
movement. Yes, the logic here is questionable.
As it happens, the cerebellum feels firmer to
the touch than other parts of the brain,
50 4 WAS MEDIEVAL CELL DOCTRINE MORE MODERN THAN WE THOUGHT?
FIGURE 4.6 The Reisch-Brunschwig diagram of
medieval cell doctrine was one of the most frequently
copied throughout this period; this one is from a book
printed in 1525. In these, fantasy and imagination are in
the first cell right behind the common sensory input, to
which three senses project. The cells are connected to
each other by the vermis (‘worm’), thought to be the
passageway by which images moved through the sys-
tem from their formation (first cell) to their being
evaluated and understood (second cell) to their being
eventually stored in memory (third cell).
FIGURE 4.7 This early fourteenth century drawing
is interesting for several reasons. First, the partitions of
the brain are labeled the anterior, middle and posterior
parts of the brain, making reference to ventricular space
even more tenuous. Second, the second cell is labeled
imagination or forms, which clearly implicates a formal
sensory image. Third, the connection between the
cells, typically labeled vermis (‘worm’) when shown in
a diagram, is here actually drawn as a worm, complete
with a little eye.
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because of its fiber structure; hence, that part
of the brain became associated with motor
functions. Since the memory cell was already
at the back of the head, following the applica-
tion of the Aristotelian cognitive model to the
ventricles and perhaps influenced by the fact
that the eyes are in the front of the head, mem-
orativa and motiva came to occupy the same
posterior cell or ventricle. One of the more
interesting consequences of this view is that
speech and memory, identified with each
other as seen in the quotations above from
Schenck and Wepfer, were associated with
the cerebellum; note again lines 6 and 7, rep-
resenting motor control of the lips in Figure
4.4. A disturbance of language, what we now
call aphasia, was for centuries referred to as a
disturbance of memory; the two weren’t the-
oretically separated until the latter part of the
nineteenth century. One might find it inter-
esting to note that some researchers today
believe that a memory impairment is at the
core of aphasia.
A SUMMARY AND OUTLINE
What have we learned? An analysis of the
first (Western) model of brain functions,
MCD, has revealed a probable continuity
with later models, rather than an aberrant
blind alley. From the twelfth century on, it is
clear that many scientists placed cognitive
functions in brain substance, meninges, and
cortex, as did virtually everyone from the
eighteenth century on. Furthermore, it is clear
that MCD models were often process models,
attempting to characterize the flow of infor-
mation from the senses to mental images (per-
ception) to memory storage and, on occasion,
to the motor control of speech and movement.
These ideas can be summarized thus:
The components of medieval cell doctrine
(a) Formation of the mental image
(i) sensation to perception
(b) Cognitive operations on the mental image
(i) some were unique to human beings
(ii) reason, judgment, creativity
(c) Storing the mental image in memory
(i) product of (b)
(ii) available for recall, recollection
(iii) basis for action
(d) Information transfer (movement)
(i) input from five senses to sensus
communis
(ii) output from last cell, motiva, to
motor system, particularly to the
tongue (speech)
(e) Localization in brain
(i) cerebral ventricles
(ii) meninges
(iii) cortex.
ACKNOWLEDGMENTS
I am grateful to Jeremy Norman for per-
mission to use the illustrations of medieval
cell doctrine from Chapter 3, ‘Medieval
period: The cell doctrine of brain function’ in
Edwin Clarke and Kenneth Dewhurst (eds)
An Illustrated History of Brain Function. Imaging
the Brain from Antiquity to the Present, Second
Edition, revised and enlarged, San Francisco:
Norman Publishing, 1996.
MORE TO EXPLORE
Green, C. D. (2003). Where did the ventricular
localization of mental faculties come from?
Journal of History of the Behavioral Sciences,39,
131–142.
Gross, C. G. (1998). Brain, vision, memory: tales in
the history of neuroscience. Cambridge, MA:
MIT Press.
Kemp, S. (1990). Medieval psychology. Westport,
CT: Greenwood Press.
Kemp, S. (1996). Cognitive psychology in the Middle
Ages. Westport, CT: Greenwood Press.
O’Neill, Y. V. (1993). Meningeal localization: a
new key to some medical texts, diagrams and
practices of the Middle Ages. Mediaevistik,6,
211–238.
MORE TO EXPLORE 51
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