The anatomy of cerebral achromatopsia: A reappraisal
and comparison of two case reports.
Paolo Bartolomeo, Anne-Catherine Bachoud-Lévi, Michel Thiebaut de
Schotten

To cite this version:
Paolo Bartolomeo, Anne-Catherine Bachoud-Lévi, Michel Thiebaut de Schotten. The anatomy of
cerebral achromatopsia: A reappraisal and comparison of two case reports.: Anatomy of cerebral
achromatopsia. Cortex, 2014, 56, pp.138-44. �10.1016/j.cortex.2013.01.013�. �inserm-00803853�

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Preprint version of the paper published on Cortex, doi: 10.1016/j.cortex.2013.01.013

The anatomy of cerebral achromatopsia:
A reappraisal and comparison of two case reports

Paolo Bartolomeo1-3, Anne-Catherine Bachoud-Lévi4-7, Michel Thiebaut de Schotten1,8

1

Inserm U975; UPMC-Paris6, UMR_S 975; CNRS UMR 7225, Centre de Recherche de
l'Institut du Cerveau et de la Moelle épinière, Groupe Hospitalier Pitié-Salpêtrière, 75013
Paris, France

2

AP-HP, Groupe Hospitalier Pitié-Salpêtrière, Fédération de Neurologie, 75013 Paris,
France

3

Dipartimento di Psicologia, Università Cattolica, 20123 Milano, Italia

4

Inserm U955, Equipe 01 Neuropsychologie interventionnelle, Institut Mondor de
Recherche Biomédicale, 94000 Créteil, France

5

Ecole Normale Supérieure, Institut d‟Etudes Cognitives, 75005 Paris, France

6

Université Paris Est, Faculté de Médecine, 94000 Créteil, France

7

AP-HP, Hôpital Henri Mondor - Albert Chenevier, Centre de référence Maladie de
Huntington, 94000 Créteil, France

8

Natbrainlab, Department of Forensic and Neurodevelopmental Sciences, Institute of
Psychiatry, King‟s College London, London, UK

Acknowledgement. We acknowledge with thanks the help of Dr Laura Robotham for the
English translation of Louis Verrey‟s paper.

Anatomy of cerebral achromatopsia

2

Abstract
Brain damage can produce acquired deficits of color perception, or cerebral
achromatopsia. In these patients, lesions tend to overlap on a restricted region in the
ventral occipitotemporal cortex, close to the reported locations of the putative V4 complex
and to foci of increased BOLD activity related to color perception in normal participants.
Unilateral lesions give rise to achromatopsia in the contralateral visual field
(hemiachromatopsia). Here we present a partial English translation of the first case report
of a hemiachromatopsic patient with detailed anatomical evidence (Madame R, Verrey,
1888), and discuss these results in relation to a more recent case report (Madame D,
Bartolomeo et al., 1997) of a patient with two consecutive hemorrhagic lesions in the
occipitotemporal regions of the two hemispheres. Strikingly, Madame D developed full-field
achromatopsia after the second lesion in the right hemisphere, without having shown any
signs of hemiachromatopsia after the first lesion in the left hemisphere. Thanks to the
comparison of the reconstructed lesion patterns between the two patients and with the
putative location of color-related areas in the human brain, we offer a possible, if
speculative, account of this puzzling pattern of anatomo-clinical correlations, based on
intra- and inter-hemispheric connectivity.

Key words: Color processing; occipital lobe; temporal lobe; brain damage; achromatopsia

Anatomy of cerebral achromatopsia

3

1. Introduction
The question of the neural mechanisms of color processing in the brain has been the
source of intense debate during the last century and it is not yet completely settled. The
core question of the debate was: is color processed in V1 along with other visual features,
or does it require a specialized color center (Zeki, 1990)? Crucial evidence for the
existence of brain regions devoted to color processing came from the study of patients
who acquired color processing deficits (so-called cerebral achromatopsia), in the context
of reasonably preserved other visual abilities such as form vision (although many
achromatopsic patients do seem to show at least subtle deficits of form vision, see Bouvier
and Engel, 2006). As noted by Zeki (1993), a turning point in the history of cerebral
achromatopsia was made by a case report made in 1888 by a Swiss ophthalmologist,
Louis Verrey. Verrey described the case of Madame R, who lost her ability to perceive
colors (but not shapes) in her right hemifield after a lesion involving the left fusiform and
lingual gyri (Verrey, 1888).
Verrey‟s demonstration of a visual impairment specific to color, with possible
sparing of other visual attributes such as form, should have prompted the search for a
“color center” in the brain. It generated instead a fierce debate (reviewed by Zeki, 1990,
1993) about the very possibility that such center could exist, contrasted with the alternative
hypothesis that color vision could simply be achieved by the striate cortex.
Major contributions to this debate came in the „70s, by the demonstration of color
and wavelength selectivity in monkey V4 area (Zeki, 1973), immediately followed by the
influential review by Meadows (1974) of 14 human patients with cerebral achromatopsia.
Meadows stressed that these patients had a perceptual color deficit, as shown by their
failure in tests such as those devised by Farnsworth (1947) or Ishihara (1974).
Achromatopsia had thus to be distinguished from color agnosia (e.g. Beauvois and
Saillant, 1985; Miceli et al., 2001). Patients with color agnosia can perform normally on
these perceptual tests, but have impaired knowledge of colors. As a consequence, they
are unable to attribute the correct color to objects presented in black and white, or to
select the correct crayon to color them. Meadows (1974) also noted that in all the cases he
reviewed the lesions involved the fusiform gyrus, the lingual gyrus, or both, and stated that
the rarity of the condition may be due to the fact that there must be involvement of areas
lying close to the striate cortex; as a consequence, large lesions would destroy the striate
cortex and produce homonymous hemianopia or cerebral blindness. Since the publication
of Meadows‟s review, there have been several other reports of acquired color processing
deficits, both full-field and concerning a visual hemifield (reviews in Bouvier and Engel,
2006; Damasio et al., 1980; Short and Graff-Radford, 2001; Zeki, 1990).
Of note, the patient described by Short and Graff-Radford (2001) developed right
hemiachromatopsia (of which she was not aware) after ischemic damage to nearly all the
fusiform gyrus and the lingual gyrus and smaller portions of the parahippocampus and
hippocampus in the left hemisphere. The authors summarized 11 other cases of cerebral
achromatopsia with neuroimaging, five of whom had bilateral achromatopsia, one rightsided and five left-sided hemiachromatopsia. Thus, although the numbers are necessarily
small due to the rarity of the condition, it does not seem to exist any preferential pattern of
laterality for the occurrence of hemiachromatopsia.
Even if the existence of areas important for color processing in the fusiform gyrus is
now accepted, their location and precise functions are still debated. Neurophysiological
and brain imaging studies in the monkey suggest that, after V1, color is handled by several
regions located from V4 to the inferotemporal cortex (areas TE and TEO, which includes
PIT whose posterior boundary adjoins area V4), rather than by a single entire extrastriate
visual area (Conway et al., 2010). Moreover, the relationships between these regions and
their putative human homologues remain controversial (Hadjikhani et al., 1998; Zeki,
2003). The collective term V4 complex (Zeki and Bartels, 1999) includes a posterior V4

Anatomy of cerebral achromatopsia

4

and a more anterior V4, which according to Zeki and Bartels (1999) corresponds to area
V8 described by Hadjikhani et al (1998). More recently, Murphey et al (2008) studied an
epileptic patient with an electrode implanted in a more rostral area in the fusiform gyrus
(midway between the occipital and temporal poles, see Fig. 1A) in the right hemisphere,
using electrical recording and electrical stimulation. The activity recorded in this area was
larger for chromatic than for achromatic stimuli, and also depended on the specific hues
presented. Electrical stimulation via the electrode evoked artificial colored percept in the
absence of visual stimuli. Thus, activity in this midfusiform area seemed directly related to
the conscious experience of color in this patient (Murphey et al., 2008). The region
examined by Murphey et al (2008) is referred to as midfusiform color center in Fig. 1A.
2. The case of Madame R (Verrey, 1888)
Although a few cases of full-field cerebral achromatopsia had been described earlier (see
Zeki, 1990, for review), to the best of our knowledge Verrey‟s paper is the first detailed
report of achromatopsia confined to one visual hemifield, with detailed anatomical
localization of the lesion. Given the importance of this case report, which is not currently
available outside historical libraries, here we report an English translation of some of the
most important passages of Verrey‟s article.
“Very few cases of hemiachromatopsia have been published to date. From the case
of the loss of the two homonymous halves of the visual field of colors, we have arrived at
the conclusion of the probable existence, in a region of the cerebral cortex, of a special
center dedicated to the chromatic sense. However, a case in which autopsy would confirm
this hypothesis was still missing until now. Furthermore, many cases of
hemiachromatopsia observed were accompanied by difficulties with reading, ranging from
simple dyslexia to a complete word blindness. The case that I describe here and that I
have been able to follow for a year has the advantage of being an unambiguous case of
hemiachromatopsia. Apart from sight dysfunctions, there was no symptom indicating brain
involvement; no aphasia symptoms, no word blindness in its proper sense, no paresis or
paralysis of the extremities. Finally, the necroscopic examination of the brain confirmed the
generally accepted hypothesis, that of the existence of a cortical center of the chromatic
sense, a hypothesis that was however disputed by several authors, and in particular
Schneller, who sought to explain these symptoms by a lesion of the chiasma or of the optic
tracts. This brain examination led us to discover a pre-existing lesion of the inferior part of
the left occipital lobe that was very precisely localized” (page 289).
Verrey then describes the clinical presentation of his patient. “Madame R, 60 years
old, from Neufchatel, came to my office for a consultation on the 4th of October in 1887.
She complained of no longer being able to read easily, a difficulty she first noticed several
weeks ago. After reading several lines, she felt tired and needed to put her book aside;
she believed that it would come to be that she would receive a stronger glasses
prescription. She associated this weakness of sight with a gastric discomfort that she had
experienced near the end of July that same year” (page 290).
In July 1887, Madame R had indeed suffered an episode of acute vertigo with
headache and vomiting. On examination, Verrey noted that reading was possible but
slowed, especially for the right part of long words. Visual fields were normal, except for a
concentric restriction to 15-20° in all directions and a slightly decreased acuity in the right
visual field. Form perception was apparently normal. However, colored paper patches of
0.5 cm in diameter, presented along a Foerster perimeter, were systematically perceived
as being grey in color in the whole right visual field, whereas they were normally perceived
in the left hemifield. The patient‟s status remained stable from July 1887 until March 1888,
when Madame R died as a consequence of a second stroke. Two weeks before the fatal
stroke, Verrey was able to re-examine Madame R and confirm the stability of her

Anatomy of cerebral achromatopsia

5

condition, except for a possible slight worsening of her visual sensitivity in the right
hemifield.
“The 20th of March at 5 in the evening, Madame R suddenly fell and lost
consciousness in a store in town where she was doing some errands. She was carried
home and her doctor, called in urgency, noted a total left hemiplegia, whole-body
anesthesia, violent vomiting, clonic and tonic convulsions of the face and on the right side.
After the 21st of March, the convulsions ceased and in the following days the coma
became deeper, her respiration stertorous; death in the morning of the 28th” (page 293f).
Autopsy discovered a large, recent hematoma in the right hemisphere, and a
smaller, more ancient lesion between the basal portion of the left occipital lobe and the
floor of the occipital horn of the left lateral ventricle. The lesion occupied the white matter
of the third occipital gyrus and destroyed more or less completely the white matter of the
occipital end of the lingual and fusiform gyri (see Fig. 1B), as well as that of the caudalventral tip of the cuneus. Ventrally, the lesion approaches the medial surface of the
occipital lobe, destroying its deep cortical layers but not reaching the superficial ones. The
lesion was an intracerebral hematoma, with a sagittal length of 3.5 cm, 1-cm wide and
1.75-cm high. Verrey concluded that “the center of the chromatic sense would lie in the
most inferior part of the occipital lobe, probably in the caudal part of the lingual and
fusiform gyri” (p. 298).
3. The case of Madame D (Bartolomeo et al., 1997)
In 1997, Bartolomeo, Bachoud-Lévi and Denes published on Cortex the case study of a
patient that did not seem to conform to the picture suggested from these cases of
hemiachromatopsia, i.e. the existence of bilateral color centers, each competent for color
processing in the contralateral hemifield (Bartolomeo et al., 1997). Madame D had two
consecutive hemorrhagic lesions in the occipitotemporal cortex and underlying white
matter, in roughly mirror-image locations. The patient was a 74-year-old, right-handed
retired secretary. She was hospitalized in May 1995 after the sudden occurrence of
headaches and visual disturbances. On admission, Madame D presented a right
homonymous hemianopia. Her reading was slow and letter-by-letter, with occasional
confusion among letters. Writing was preserved. She showed a mild anomia, without any
comprehension or repetition deficits, which subsided a few weeks later. CT scan revealed
a left occipitotemporal hematoma. An MRI performed in Sep. 1995 showed a reduction in
the size of the hematoma, which involved Brodmann‟s areas 18,19 and 37 (see Fig. 1C).
Two months after lesion occurrence, visual fields appeared normal on clinical
examinations. Goldman perimetry, however, showed the persistence of a mild paracentral
scotoma. This deficit, situated between 38 and 158 for the left eye and 28 and 258 for the
right eye (see Fig. 2 in Bartolomeo et al., 1998a), was apparent only with the II test, and
thus allowed some residual visual processing. In particular, on clinical testing color naming
was entirely normal in the right hemifield. Thus, after the first lesion in the left hemisphere,
Madame D had no signs of right hemiachromatopsia on clinical examination; she had a
moderate alexia (see Bachoud-Lévi and Bartolomeo, 2003), but kept enjoying painting and
remained able to accurately name color patches in either hemifield. Seven months later,
while Madame D was recovering from pure alexia, she unfortunately suffered from a
second stroke, in an approximately symmetrical location in the right hemisphere (see Fig.
1C). Upon occurrence of the second stroke, Madame D suddenly found herself unable to
identify faces, objects and letters, despite reasonably well preserved elementary visual
abilities (Bartolomeo et al., 1998a; Bartolomeo et al., 1998b, 2003); importantly, she had
also become full-field achromatopsic, and complained to see the world in shades of grey
or, later on, in reddish-brown nuances.
Thus, Madame D developed full-field, clinically evident achromatopsia after the
second lesion in the right hemisphere, without any clinical signs of right

Anatomy of cerebral achromatopsia

6

hemiachromatopsia after the first lesion in the left hemisphere. The 1997 Cortex study did
not offer a complete account of this “puzzling sequence of events”. The authors noted that
their results supported the hypothesis of a critical role of the right hemisphere in color
processing, but this putative pattern of hemispheric laterality has not been confirmed by
subsequent neuroimaging studies. It is, moreover, inconsistent with the case of Madame R
(Verrey, 1888), who had right hemiachromatopsia after a left occipitotemporal lesion.
4. How can similar
hemiachromatopsia?

left

hemisphere

lesions

give

rise

or

not

to

right

There is, thus, a stark contrast between Madame R‟s right hemiachromatopsia and
Madame D‟s preserved full-field color vision after lesions in the ventral posterior regions of
their left hemisphere. Why should a left hemispheric lesion give such different outcomes in
these patients?
A first account might rest on the possibility of individual differences in the
hemispheric laterality of the color centers in the brain. According to this hypothesis, the
right hemisphere color centers could have been responsible for full-field color processing
in Madame D, but not in Madame R. A case report of full-field achromatopsia after an
apparently unilateral right hemisphere lesion (Setälä and Vesti, 1994) may indeed suggest
that in some individuals color-related areas in the right hemisphere have bilateral
competence. This might indeed have been the case for Madame D. As the authors
themselves acknowledge, however, “the CT and MRI findings do not totally rule out the
existence of bilateral lesions; there may also be an incipient lesion in the left angular or
fusiform gyrus, not visible in CT and MRI” (Setälä and Vesti, 1994, p. 35). Furthermore,
this possibility does not seem consistent with the remaining available evidence from braindamaged patients, which suggest that unilateral brain damage can give rise to
hemiachromatopsia for the opposite hemifield, without appreciable differences between
right and left hemisphere lesions (Short and Graff-Radford, 2001). Moreover, the available
data do not suggest the possibility of an atypical pattern of hemispheric laterality for either
Madame R or Madame D (who was right-handed).
A second possibility is that the left hemisphere lesions damaged different
anatomical systems in the two patients. A precise test of this hypothesis would require
state-of-art images of the lesions of Madame R and Madame D, which are unfortunately
not available. However, based on the autopsy report and figure provided by Verrey (1888)
for Madame R, and on CT and clinical MRI scans obtained for Madame D, we
reconstructed their lesions on standardized brain slices, shown in Figure 1 together with
the location of areas crucial for color processing.
5. Methods
Mapping
of
the
lesions
was
performed
by
using
MRIcron
(http://www.mccauslandcenter.sc.edu/mricro/mricron). For each patient, we rotated the
Colin27 template (Holmes et al., 1998) provided in MRIcron from the MNI space to the
orientation of sectional drawings for Madame R (Verrey, 1888), and of individual clinical
MRI scans for Madame D (Bartolomeo et al., 1998a; Bartolomeo et al., 1997). The lesion
was then drawn on the reoriented template and subsequently taken back to the MNI space
using the inverse rotation (see Doricchi and Tomaiuolo, 2003).
The ventral part of V4 (hOC4v, Rottschy et al., 2007) and the subdivisions of the
fusiform gyrus (FG1 and FG2, Caspers et al., 2012) were obtained from recent postmortem cytoarchitectonic atlases (SPM Anatomy Toolbox V2, http://www.fz-juelich.de) and
overlapped on the Colin 27 template. These maps were thresholded in order to only show
voxels with a probability superior to 50% (above the chance level of being in the given
area for a given voxel).

Anatomy of cerebral achromatopsia

7

MNI coordinates for area V8 and the midfusiform color area were respectively
extracted from previous functional MRI study (Hadjikhani et al., 1998) and direct electrical
recording and stimulation in an epileptic patient (Murphey et al., 2008), and plotted in the
Colin27 template. Note that when areas were reported in Talairach coordinates we used
the
Yale
non-linear
MNI
2
Talairach
conversion
(http://www.bioimagesuite.org/Mni2Tal/index.html) in order to obtain MNI coordinates.

Anatomy of cerebral achromatopsia

8

Figure 1: A. Color-related areas in the human brain. Cytoarchitectonic areas hOC4v
(Rottschy et al., 2007), FG1, FG2 (Caspers et al., 2012), the functionally activated area V8
(Hadjikhani et al., 1998) and the midfusiform color center explored in the right hemisphere
of an epileptic patient by Murphey et al (2008). B. Reconstruction of Madame R‟s lesion.
C. Reconstruction of Madame D‟s lesion.
6. Results
The results of the anatomical analysis are displayed in Figure 1. Inspection of the figure
suggests that Madame R‟s lesion encroached directly upon areas crucial for color
processing (V4/V8). This provides a straightforward explanation for her
hemiachromatopsia, precisely along the lines suggested by Verrey in the original case
report (Verrey, 1888). On the other hand, Fig. 1 also indicates that Madame D‟s first, lefthemisphere lesion did not damage directly the color processing regions. However, as
suggested by the predominant involvement of the white matter nearby these regions,
Madame D‟s first lesion could have disconnected these posterior color-processing areas
from more anterior color-related regions, such as the midfusiform color center putatively
implicated in conscious color experience (Murphey et al., 2008). Nevertheless, the callosal
connections of V4 might have prevented Madame D‟s first lesion from producing
hemiachromatopsia. It is well known that the callosal connections of V4 (Fig. 2) are much
more widespread than those of V1 and V2, which are limited to the representation of the
vertical meridian (Clarke and Miklossy, 1990; Zeki, 1990).

Anatomy of cerebral achromatopsia

9

Figure 2: Coronal view of the callosal connections (in red) of V4 (modified from Clarke and
Miklossy, 1990). Post-mortem studies localized V4 in the collateral sulcus overlapping with
the occipital portion of the fusiform gyrus in humans (Rottschy et al., 2007). Following
degenerating axons from occipital lobes of six human brains with unilateral occipital
infarctions, Clarke and Miklossy (1990) were able to describe the projections of the corpus

Anatomy of cerebral achromatopsia

10

callosum on a region of the fusiform gyrus which presumably contains the human
analogue of the V4 complex.
Color-related information might thus have traveled from V1 to V4 in the left hemisphere
and then crossed to the right hemisphere thanks to V4 callosal connections, with
consequent full-field conscious color experience. Madame D‟s second lesion appears,
instead, to have damaged at least partially the right hemisphere V4 (Fig. 1C), thus
impairing this pathway, with consequent full-field achromatopsia.
7. Discussion
Color processing in the brain proceeds along multiple stages, starting from the activity of L,
M, and S cones in the retina to color-opponent neurons in the lateral geniculate nucleus
and V1 (Conway et al., 2010), to hue maps with color constancy in V2 and V4 (Roe et al.,
2012) and finally more “cognitive” aspects in more anterior areas in the temporal cortex.
These high-level, cognitive aspects include elements of color knowledge (i.e., knowledge
about prototypical object colors, Miceli et al., 2001) and perhaps the possibility of full
conscious experience of color (Murphey et al., 2008).
The present reappraisal of two published cases of acquired color deficits
contributes to our understanding of the role of the human homologue of V4 to color
perception, by showing that direct damage to the putative human localization of the V4
complex is correlated to a perceptual color processing deficit in the contralateral hemifield
(Verrey, 1888), and resolves the apparently contradictory findings, obtained in another
patient (Bartolomeo et al., 1997), that occipitotemporal damage in the left hemisphere did
not produce hemiachromatopsia, whereas subsequent damage to the right hemisphere
was able to determine full-field achromatopsia.
Note, however, that experimental evidence from intra-operative stimulation (Lee et
al., 2000) and studies of visual hallucinations (ffytche et al., 1998) suggest that V4 might
have in itself a role in conscious processing of color (Zeki, 2005). If so, then the reason
why Madame D did not develop hemi-achromatopsia after her left hemisphere lesion is
because V4 was not affected. It remains, however, difficult to explain why Madame D
developed full field achromatopsia after her second lesion to right V4, given that left V4
was unaffected throughout. In addition to the above-mentioned possibility of an individual
right-hemisphere dominance for color processing, one might posit changes in input to left
V4 at initial presentation, as implied by the transient hemianopia. Perhaps during the
seven months prior to the second lesion Madame D was relying on callosal connections
from right V4 to left V4 for full field colour vision. If, however, conscious color experience
does not require solely the activity of V4, but also its integration with more rostral regions
such as the midfusiform color area, then our present hypothesis seems to account for
most of the available evidence.
Two limits of the present study must be acknowledged. First, it is difficult to
precisely estimate the location and extent of the brain lesions of these patients in the
absence of high-resolution neuroimaging data. Second, there are still many uncertainties
concerning the homologies between monkey and human brain in these occipitotemporal
regions. Despite these problems, the present results contribute to confirm the importance
of the human homologue of V4 in color processing, as well as the putative role of interhemispheric interactions between these regions. It is likely from the present data that a
lesion of V4 can profoundly impair the visual experience of color, perhaps by depriving
more anterior areas of crucial input. Thus, rather than a single “special center dedicated to
the chromatic sense” (Verrey, 1888), a complex network of processing streams in the
occipitotemporal cortex seems to be essential to several aspects of color-related cognition.
Reviewing the history of cerebral achromatopsia, Semir Zeki noted that “the optic
radiations and the white matter in general were to come to the rescue of many a faltering

Anatomy of cerebral achromatopsia

11

argument” (Zeki, 1993, page 47) during the debate about the color centers in the brain. In
the present comparison between the cases of Madame R and Madame D, however,
simple consideration of cortical lesion location did not permit to reach a satisfactory
account of the dramatic differences between the consequences of their brain lesions. On
the other hand, by taking into account white matter pathways, an approach sometimes
defined as hodotopic (see Catani and ffytche, 2005), it was possible to articulate a more
plausible, if speculative, explanation of an otherwise mysterious pattern of lesion-symptom
mapping.

Anatomy of cerebral achromatopsia

12

8. References
Bachoud-Lévi AC, and Bartolomeo P. Mechanisms of pure alexia: Spatially-based
impairment, letter identification deficit, or both? Neurocase 9 (2): 164-176, 2003.
Bartolomeo P, Bachoud-Lévi AC, de Gelder B, Denes G, Dalla Barba G, Brugières P, and
Degos JD. Multiple-domain dissociation between impaired visual perception and
preserved mental imagery in a patient with bilateral extrastriate lesions.
Neuropsychologia 36 (3): 239-249, 1998a.
Bartolomeo P, Bachoud-Lévi AC, Degos JD, and Boller F. Disruption of residual reading
capacity in a pure alexic patient after a mirror-image right hemispheric lesion. Neurology
50 (1): 286-288, 1998b.
Bartolomeo P, Bachoud-Lévi AC, Degos JD, and Boller F. Right hemisphere contributions
to residual reading in pure alexia: Evidence from a patient with subsequent bilateral
strokes. In: Zaidel E, and Iacoboni M (Eds.), The Parallel Brain: The Cognitive
Neuroscience of the Corpus Callosum. The MIT Press: Cambridge, MA, 2003. pp. 500506.
Bartolomeo P, Bachoud-Lévi AC, and Denes G. Preserved imagery for colours in a patient
with cerebral achromatopsia. Cortex 33 (2): 369-378, 1997.
Beauvois MF, and Saillant B. Optic aphasia for colours and colour agnosia: A distinction
between visual and visuo-verbal impairments in the processing of colours. Cognitive
Neuropsychology 2 (1): 1-48, 1985.
Bouvier SE, and Engel SA. Behavioral deficits and cortical damage loci in cerebral
achromatopsia. Cerebral Cortex 16 (2): 183-191, 2006.
Caspers J, Zilles K, Eickhoff SB, Schleicher A, Mohlberg H, and Amunts K.
Cytoarchitectonical analysis and probabilistic mapping of two extrastriate areas of the
human posterior fusiform gyrus. Brain Structure and Function, 2012.
Catani M, and ffytche DH. The rises and falls of disconnection syndromes. Brain 128 (Pt
10): 2224-2239, 2005.
Clarke S, and Miklossy J. Occipital cortex in man: organization of callosal connections,
related myelo- and cytoarchitecture, and putative boundaries of functional visual areas.
The Journal of comparative neurology 298 (2): 188-214, 1990.
Conway BR, Chatterjee S, Field GD, Horwitz GD, Johnson EN, Koida K, and Mancuso K.
Advances in Color Science: From Retina to Behavior. Journal of Neuroscience 30 (45):
14955-14963, 2010.
Damasio A, Yamada T, Damasio H, Corbett J, and McKee J. Central achromatopsia:
Behavioral, anatomic, and physiologic aspects. Neurology 30: 1064-1071, 1980.
Doricchi F, and Tomaiuolo F. The anatomy of neglect without hemianopia: a key role for
parietal-frontal disconnection? NeuroReport 14 (17): 2239-2243, 2003.
Farnsworth D. Farnsworth dichotomous test for colour-blindness - panel D-15. The
Psychological Corporation: New York, 1947.
ffytche DH, Howard RJ, Brammer MJ, David A, Woodruff P, and Williams S. The anatomy
of conscious vision: an fMRI study of visual hallucinations. Nat Neurosci 1 (8): 738-742,
1998.
Hadjikhani N, Liu AK, Dale AM, Cavanagh P, and Tootell RB. Retinotopy and color
sensitivity in human visual cortical area V8. Nat Neurosci 1 (3): 235-241, 1998.
Holmes CJ, Hoge R, Collins L, Woods R, Toga AW, and Evans AC. Enhancement of MR
images using registration for signal averaging. J Comput Assist Tomogr 22 (2): 324333, 1998.
Ishihara S. Tests for colour-blindness. Kanehara Shup: Tokio, 1974.
Lee HW, Hong SB, Seo DW, Tae WS, and Hong SC. Mapping of functional organization in
human visual cortex: electrical cortical stimulation. Neurology 54 (4): 849-854, 2000.

Anatomy of cerebral achromatopsia

13

Meadows JC. Disturbed perception of colours associated with localized cerebral lesions.
Brain 97: 615-632, 1974.
Miceli G, Fouch E, Capasso R, Shelton JR, Tomaiuolo F, and Caramazza A. The
dissociation of color from form and function knowledge. Nature Neuroscience 4 (6):
662-667, 2001.
Murphey DK, Yoshor D, and Beauchamp MS. Perception matches selectivity in the human
anterior color center. Current Biology 18 (3): 216-220, 2008.
Roe AW, Chelazzi L, Connor CE, Conway BR, Fujita I, Gallant JL, Lu H, and Vanduffel W.
Toward a unified theory of visual area V4. Neuron 74 (1): 12-29, 2012.
Rottschy C, Eickhoff SB, Schleicher A, Mohlberg H, Kujovic M, Zilles K, and Amunts K.
Ventral visual cortex in humans: Cytoarchitectonic mapping of two extrastriate areas.
Human Brain Mapping 28 (10): 1045-1059, 2007.
Setälä K, and Vesti E. Acquired cerebral achromatopsia: A case report. Neuroophtalmology 14 (1): 31-36, 1994.
Short RA, and Graff-Radford NR. Localization of hemiachromatopsia. Neurocase 7 (4):
331-337, 2001.
Verrey L. Hémiachromatopsie droite absolue. Conservation partielle de la perception
lumineuse et des formes. Ancien kyste hémorrhagique de la partie inférieure du lobe
occipital gauche. Arch. Ophtalmol. (Paris) 8: 289-300, 1888.
Zeki S. Colour coding in rhesus monkey prestriate cortex. Brain Res 53 (2): 422-427,
1973.
Zeki S. A century of cerebral achromatopsia. Brain 113: 1721-1777, 1990.
Zeki S. A Vision of the Brain. Blackwell Scientific Publications: Oxford, 1993.
Zeki S. Improbable areas in the visual brain. Trends Neurosci 26 (1): 23-26, 2003.
Zeki S. The Ferrier Lecture 1995 behind the seen: the functional specialization of the brain
in space and time. Philos Trans R Soc Lond B Biol Sci 360 (1458): 1145-1183, 2005.
Zeki S, and Bartels A. The clinical and functional measurement of cortical (in)activity in the
visual brain, with special reference to the two subdivisions (V4 and V4 alpha) of the
human colour centre. Philosophical Transactions of the Royal Society B: Biological
Sciences 354 (1387): 1371-1382, 1999.