Language, thought and color: Recent developments

Abstract

The classic issue of color naming and color cognition has been re-examined in a recent series of articles. Here, we review these developments, and suggest that they move the field beyond a familiar rhetoric of 'nature versus nurture', or 'universals versus relativity', to new concepts and new questions.

Full text

Language, thought, and color:
Whorf was half right
Terry Regier
1*
and Paul Kay
2*
1
Dept. of Psychology, University of Chicago
2
Dept. of Linguistics, University of California, Berkeley
The Whorf hypothesis holds that we view the world
filtered through the semantic categories of our native
language. Over the years, consensus has oscillated be-
tween embrace and dismissal of this hypothesis. Here,
we review recent findings on the naming and perception
of color, and argue that in this semantic domain the
Whorf hypothesis is half right, in two different ways: (1)
language influences color perception primarily in half
the visual field, and (2) color naming across languages is
shaped by both universal and language-specific forces.
To the extent that these findings generalize to other
semantic domains they suggest a possible resolution
of the debate over the Whorf hypothesis.
The state of the debate
A classic debate in cognitive science concerns the relation
between language and perception. At one pole of this
debate is the relativist stance, which holds that our per-
ception of the world is shaped by the semantic categories of
our native language, and that these categories vary across
languages with little constraint - a view often associated
with Benjamin Lee Whorf. At the other pole is the uni-
versalist stance, which holds instead that there is a uni-
versal repertoire of thought and perception that leaves its
imprint on the languages of the world. Over the years,
consensus has swung back and forth between these two
poles.
The domain of color has furnished an empirical locus
classicus of the debate for the last half-century. In a 2006
review [1] we suggested that the universalist-versus-rela-
tivist debate with respect to color often conflates 2 distinct
questions:
1. Do color terms affect color perception?
2. Are color categories determined by largely arbitrary
linguistic convention?
A relativist would respond ‘yes’ to both questions,
whereas a universalist would respond ‘no’ to both. How-
ever, that review argued that empirically the answers to
the two questions do not match. Specifically, it was argued
on the basis of evidence then available that color terms do
affect color perception (yes to question 1), but that there are
also universal tendencies in color naming (no to question
2). It was argued that the universalist/relativist opposition
is unhelpful as a conceptual structuring device, since it
does not accommodate these realities.
In the years since then, new findings have arisen that
suggest a subtler view. The new evidence suggests that
Whorf was partly right with respect to each of these two
questions. With respect to question 1, color names do
influence color perception –but primarily in the right
visual field, and less so in the left. With respect to question
2, color naming across languages does reflect universal
tendencies, as shown in earlier work –but also some degree
of local linguistic convention. These findings suggest a way
in which the recently re-opened debate over language and
thought in the color domain might be resolved. And to the
extent that these findings generalize to other semantic
domains, they suggest a possible resolution of the Whorf
debate more broadly.
Language affects perception - in half the visual field
Does language affect perception? As noted above, several
studies suggest that the answer is ‘yes’, at least in connec-
tion with color. These studies have shown that there is
‘categorical perception’ (CP: faster or more accurate dis-
crimination of stimuli that straddle a category boundary)
for color, and that differences in color category boundaries
between languages predict where CP will occur [2–7].
Moreover, several of these studies, and others [e.g. 8] have
shown that color CP disappears with a concurrent verbal
interference task, confirming that color CP is language
based.
However, this straightforward Whorfian answer - and
the yes-or-no framing of the very question ‘does language
affect perception?’ - obscure an interesting possibility: that
language might affect half of perception. Specifically,
language might be expected to shape perception primarily
in the right visual field (RVF), and much less if at all in the
left visual field (LVF). This expectation follows from the
observations that the left hemisphere (LH) of the brain is
dominant for language, and that the visual fields project
contralaterally to the brain. On this view, half of our
perceptual world might be viewed through the lens of
our native language, and half viewed without such a
linguistic filter.
This proposal was first advanced and tested in a study
by Gilbert et al. [8] that probed the perceptual discrimi-
nation of colors straddling the boundary between green
and blue, a boundary present in English but absent in
many other languages. In this study, American English
speaking participants first saw a central fixation cross, and
Review
Corresponding authors: Regier, T. (terry.regier@gmail.com);
Kay, P. (paulkay@berkeley.edu)
*
The two authors contributed equally to this work..
TICS-795; No of Pages 8
1364-6613/$ –see front matter ß2009 Elsevier Ltd. All rights reserved. doi:10.1016/j.tics.2009.07.001 Available online xxxxxx 1

then a ring of colored squares arrayed around it (Figure 1b).
All of the squares were of the same color except for one (the
target), and participants were required to identify whether
the target appearedon the left or right half of the display by
pressing a button with the corresponding hand. Critically,
the target color had either the same nameas the color of the
other squares (e.g. a green against a background of a differ-
ent green, as in stimuluspair A,B in Figure 1a), or a different
name (e.g. a green against a background of a blue, as in
stimulus pair B,C in Figure 1a).
One of Gilbert et al.’s experiments is depicted in
Figure 1. As shown in Figure 1c, cross-category targets
were identified faster than same-category targets in the
RVF only. When a concurrent task requiring verbal
resources (remembering an eight-digit number) was
added, the RVF color CP effect disappeared, in fact was
reversed, reinforcing the interpretation that when RVF
color CP is found, it has a verbal basis [4,5]. In a second
experiment (not shown in Figure 1) Gilbert et al. replicated
these findings, and also found that RVF CP was not dis-
rupted by a non-verbal interference task of difficulty com-
parable to the verbal interference task - again
strengthening the conclusion that the lateralization pat-
tern is linguistic in origin. Drivonikou et al.[9] reanalyzed
by visual field color search data that had been collected
earlier for a different study and found predominantly RVF
color CP; they ran a new experiment similar to that of
Gilbert et al. and found color CP in the RVF superior to
that in the LVF. However their finding of significant,
although weaker, color CP in the LVF diverged from the
Gilbert et al. result; the longer response time in the Dri-
vonikou data suggest that this apparent RH CP might be
the result of longer RTs permitting cross-callosal transfer
and/or scanning (for further discussion of this possibility in
these and other studies see [7,10,11]).
Gilbert et al. [8] also reported that a callosotomy (‘‘split-
brain’’) patient showed RVF color CP with no trace of LVF
color CP. A separate study [12] reported a similar result
with a second callosotomy patient in an experiment in the
same paradigm as [8] but using non-color stimuli, namely
silhouettes of dogs and cats. When this experiment was run
with normal adult participants, CP was found in both
visual fields but again more strongly in the RVF than
LVF, and again this pattern was disrupted by a verbal
but not a non-verbal interference task. These results
confirm that linguistic CP is localized to the LH and
suggest that the phenomenon is not limited to color.
Roberson, Pak & Hanley [7] examined a color boundary
in Korean that does not correspond to any English color
boundary in a setup very similar to that of [8]. Their eight
fastest subjects showed color CP in the RVF only, whereas
their eight slowest subjects showed color CP in both visual
fields. Roberson et al. infer that the slower subjects’ LVF
CP probably reflects cross-callosal transfer. The literature
so far shows a general tendency for color CP to be restricted
to the RVF for short RTs, to appear in the LVF as well but
to a lesser degree in medium length RTs, and to show up
more or less equally in both VFs with very long RTs,
Figure 1. Lexical categories influence perception in the RVF. (a) Print-rendered versions of the four colors used. (b) Sample display for the visual search task. Participants
were required to press one of two response keys, indicating the side containing the target color. (c) In the no-interference condition, category effect in the RVF only. (d)
Effect reversed with verbal interference. *,P<0.05, two-tailed ttest; df =10; ns, nonsignificant. Values are mean SEM. Source: [8].
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reinforcing the conclusion that LVF CP in adults reflects
cross-callosal transfer, and perhaps scanning in some
cases. Roberson, Pak & Hanley [7] is the only published
study at this time to have tested lateralized color CP at a
color category boundary other than those found in English.
So far, everything we have considered points to
language-driven CP originating in the LH manifesting
itself in the RVF. However, this picture is complicated
by evidence of prelinguistic - and thus non-linguistic -
CP in infants [e.g. 13,14,15] and the finding that color
term knowledge does not affect color CP in toddlers [16].
The existence of prelinguistic CP has recently been both
contested [17,18] and defended [19]. If confirmed, it raises
an important question: What relation does prelinguistic
CP bear to the language-driven RVF-lateralized color CP
universally observed in speaking adults? Prelinguistic
color CP has been observed along boundaries correspond-
ing to some of those in familiar European (and many other)
languages. Thus, a natural possibility is that prelinguistic
categories serve as a starting-point for the later elabor-
ation of linguistic categories.
Franklin et al. [20] compared infant and adult perform-
ance on a visual search task much like that of [8]. Since
infants cannot reliably respond through a button press, a
different response measure was used: the time it took to
initiate an eye movement from central fixation to a target
dot, displayed in one color against a uniform background of
a different color. As in previous experiments the target and
background were either of the same category (e.g. two
blues) or of different categories (one green, the other blue).
This method was used with adults (with less easily dis-
criminable colors) and showed the expected RVF-dominant
CP of color. In contrast, prelinguistic infants showed no CP
in the RVF, and clear CP in the LVF.
Is the migration of the category effect - from the RH/LVF
in infants to the LH/RVF in adults - caused by the acqui-
sition of color terms? To pursue this question more precisely,
Franklin et al. [10] tested toddlers aged two to five with the
same procedure. The children’s grasp of the relevant color
terms blue and green was assessed and the toddler subjects
sorted readily into two groups: ‘‘learners’’, who had not yet
acquired these color terms, and ‘‘namers’’, who had. In the
visual search task the learners patterned like infants: they
displayed color CPin the LVF but not theRVF; whereas the
namers patterned like adults: CP in the RVF but not the
LVF. These results remain when age is added as a covariate
to the analysis, as shown in Figure 2.
This study suggests strongly that it is acquisition of
color terms per se that causes the shift of color CP from RH
to LH, a conclusion that raises several questions. What is
the nature of this shift? Are the RH prelinguistic categories
transported to the LH, where they serve as a starting-point
for the elaboration of LH linguistic categories? Or are LH
linguistic categories constructed de novo by language,
without reference to the RH prelinguistic categories? In
either case, why is there no trace left of the RH prelinguis-
tic categories once color terms have been learned - are they
permanently erased [21], or merely suppressed on-line by
language?
We can presently answer only one of these questions,
and only tentatively. It seems likely that RH prelinguistic
categories are indeed permanently erased by language,
rather than merely temporarily suppressed by it. Tellingly,
split-brain patients, in whom the hypothetical channel of
suppression has been severed, show no evidence of LVF/
RH CP [8,12]. Further research is needed to settle this
question, along with the other questions opened by these
hemisphere-switching findings from infants and toddlers.
So far, our discussion of the brain bases of color CP, and
its lateralization, has been based on inference from beha-
vioral experiments. Recently however a number of ERP
and fMRI studies have probed this issue more directly.
Three studies deal with lateralization per se. Liu et al. [22]
performed a lateralized visual search experiment using the
procedure of [8], while recording brain activity by EEG.
They focused on a specific ERP (event-related potential)
component that is typically evoked in visual search for a
perceptually unique target among distractors. They found
that this component was present in the contralateral hemi-
sphere for both within- and cross-category targets - but
only in the left hemisphere did the amplitude of this
component for cross-category targets exceed that for
within-category targets, providing electrophysiological
confirmation of the (behaviorally established) lateraliza-
tion of the categorical perception of color. In a lateralized
event related fMRI study, Siok et al. [23] found that
discriminating colors of different lexical categories (versus
the same category) elicited faster and stronger response in
the left hemisphere language regions, especially when the
colors were presented in the right visual field. They found
further that only for these same stimuli was activation
significantly enhanced in the visual areas responsible for
color perception, suggesting that the language areas might
act as a top-down control source on the visual areas in color
perception. Another fMRI study [24] found that speeded
perceptual discrimination of colors which are easy to name,
relative to colors that are harder to name, activates left
hemisphere regions that mediate language processes:
these same regions were independently shown to be acti-
vated when subjects named colors aloud.
Figure 2. Category effect in the LVF for toddlers who have not yet learned the
words blue and green, and in the RVF for those who have. The dependent measure
is the estimated mean of the log transformation of initiation time (ms), estimated
for when variance due to age is accounted for. Error bars are within-subjects 95%
confidence intervals calculated by using the error term from the three-way
interaction. Source: [10].
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Three other recent ERP studies examine neural corre-
lates of color CP more generally, in the context of beha-
vioral tasks requiring the visual discrimination of colors.
Fonteneau & Davidoff [25] found that the peak latency in
ERP for a small color difference that bridged a color term
boundary (195 ms) was shorter than that for an equally-
sized color difference that did not bridge a color term
boundary (214 ms) - providing evidence for a neural corre-
late of categorical perception of color. Thierry et al. [26]
found that speakers of Greek, which has separate basic
color terms for light and dark blue, showed visual mis-
match negativity, an index of automatic and preattentive
change detection, for luminance modulations in the blue
area, whereas English speakers did not, a difference that
appeared at around 200 ms. These results imply a role of
the language-specific category boundary early in color
discrimination. Holmes et al.[27] compared English-
speaking subjects’ brain responses to same- versus cross-
category color differences; ERPs showed shorter latencies
for early components to cross-category differences than for
within-category differences, mirroring RT results on a
behavioral version of the task and providing evidence for
an early role for categorical differences in color perception.
Later components also differentiated between- and within-
category differences, suggesting influence of color
categories on post-perceptual processing as well.
Altogether, the recent electrophysiological and imaging
studies (1) support earlier behavioral findings of linguistic
category influence in colordiscrimination via involvement of
left hemisphere language regions, (2) demonstrate that CP
influence for color can be exerted both early and late in
processing, and is thus likely to be partially perceptual as
well as post-perceptual, and (3) show that lexical differences
between languages (Greek vs. English) are reliably repro-
duced in a standard ERP indication of pre-attentive novelty
of a stimulus. Also, (4) one study suggests that regions of the
left hemisphere that process language act as a top-down
influence on the function of visual areas in color perception.
More broadly, it now appears uncontroversial that once
language is learned, its categories shape perceptual dis-
crimination primarily in the left hemisphere/right visual
field and less so if at all in the right hemisphere/left visual
field - a specific and unexpected sense in which Whorf was
half right.
Where do color categories come from?
If linguistic color categories do affect perception, at least in
half the visual field, where do those categories come from?
Why do languages have the color categories they do? An
exploration of this question suggests another way in which
Whorf was half right.
According to an influential universalist view, color
categories across languages are organized around the uni-
versal focal colors black, white, red, green, yellow and blue
[28–30]. This view gained support from the finding that
color memory appeared to be privileged for these colors,
even in speakers of a language with a color naming system
quite different from that of English [29,30]. For many years
the prevailing consensus was that these focal colors, and
prelinguistic color categories organized around them,
reflected in prelinguistic CP as discussed above, consti-
tuted a cognitive foundation for universals of color naming,
and the debate seemed settled.
Starting in 1999, however, the debate was re-opened by a
study of the Berinmo language (Sepik-Ramu family, Papua
New Guinea) by Debi Roberson and colleagues [31,32].In
this study, Roberson and colleagues failed to replicate the
finding of privileged memory for the proposed focal colors; in
addition, they found categorical perception of color at
language-defined boundaries. They concluded that there
are no universal foci, that categories therefore cannot be
organized around them, and that ‘‘color categories are
formed from boundary demarcation based predominantly
on language’’ [32], subject to the constraint of ‘grouping by
similarity’: namely, that categories must form contiguous
regions of color space. The implication is that apart from
that rather loose constraint, category boundaries are deter-
mined exclusively by local linguistic convention. These
authors held up Berinmo as a counterexample to universals
of color naming: ‘no evidence was found for [Berinmo color
categories] to correspond to a limited set of universal basic
color categories’ [33] and they interpreted their results as
providing ‘evidence in favor of linguistic relativity’ [32].
Thus, this study constituted a Whorfian challenge to the
then-reigning universalist consensus concerning why
languages have the categories they do.
Since then, considerable evidence has been advanced for
universal tendencies in color naming [e.g. 34,35], as well as
evidence supporting relativity [e.g. 6,17,36,37]. This evi-
dence has often been presented as unambiguously support-
ing one side or the other in the debate, in articles with titles
such as ‘Focal colors are universal after all’ [35] and ‘Color
categories vary with language after all’ [38]. Below we
briefly review recent contributions to this exchange, and
then discuss subsequent proposals that might help to
reconcile these two positions, and perhaps resolve the
debate.
Kay and Regier [39] compared the boundaries of Ber-
inmo color categories with those of the 110 languages of the
World Color Survey (WCS) [40]. They reasoned that if the
only constraint on color categories is that they must occupy
contiguous regions of color space, as had been suggested,
there should be nothing privileged about the location of
category boundaries in Berinmo –the boundaries could
just as easily have been drawn elsewhere as long as each
category remained a connected region. To probe this, they
created artificial variants of the Berinmo color naming
system by rotating that system in the hue dimension by
2,4,... etc. hue columns, all the way around the hue circle,
as illustrated in Figure 3(a) - preserving the shape and
thus contiguousness of the categories, but altering their
actual location in color space. For each version of Berinmo,
it was determined to what extent category boundaries in
that system matched those in each language of the WCS. It
was found that the unrotated (attested) version of Berinmo
matched boundaries in the WCS better than did any
rotated (hypothetical) version of Berinmo, as shown in
Figure 3(b). This finding demonstrates that color naming
in Berinmo reflects universal forces that constrain the
location, not just the connectedness, of categories.
Lindsey and Brown [41] tested for universal tendencies
in color naming in a different way, using the same WCS
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data. They considered the color naming systems of individ-
uals, rather than summary measures capturing the systems
of entire languages, as previous analyses had used, and
performed cluster analyses based on these individual-level
data. They found clusters that ‘generally correspond to
readily identifiable English categories ... or their compo-
sites’. For instance, a cluster analysis with two clusters
revealed categories ‘readily described as WARM (including
red, yellow, orange, and pink) and COOL(including blue and
green)’ [41,p. 16609]. Cluster analyses with more clusters
revealed more fine-grained categories that again closely
resemble those isolated on a less rigorous basis in the earlier
literature [e.g. 42,43]. Further recent studies also establish
universal constraints on color naming [44,45].
However, there is also evidence consistent with the
relativist view that boundaries are determined by
language. Roberson, Davidoff, Davies, and Shapiro [6]
compared color naming and cognition in English, Berinmo,
and in Himba, a language of Namibia. They found that
Berinmo and Himba had similar but distinct systems of
color naming. On a universal-foci account, Himba and
Berinmo would receive the same analysis: each language
has terms that appear to be focused in black, white, green,
red, and yellow. Yet some of the boundaries among these
categories differ noticeably between the two languages,
and speakers of each language exhibit categorical percep-
tion of color at their native language’s boundaries. This
finding suggests strongly that there is more to the deter-
mination of boundaries than groupings of universal foci,
and that linguistic convention might indeed play some role
in determining where boundaries are drawn. This view is
confirmed by recent evidence from Greek–English bilin-
guals, in which the foci themselves shift their position
somewhat, under the influence of the categories of the
newly-learned language [37]. Finally, and most generally,
qualitative inspection of the 110 languages of the WCS
reveals some language-specific idiosyncrasies against the
backdrop of broad universal tendencies [46].
On the whole, then, the universalist and relativist views
regarding color naming are each partly supported and
partly challenged by existing empirical data. This empiri-
cally complex picture can be accounted for in theoretically
simple terms. Jameson & D’Andrade [47] suggested that
patterns of color naming could be attributed to irregula-
rities in the shape of perceptual color space combined with
general human cognitive tendencies toward constructing
informationally efficient systems of concepts:
One possible explanation [for patterns of color nam-
ing in languages] is...the irregular shape of the color
space. ...Hue interacts with saturation and lightness
to produce several large ‘‘bumps’’; one large bump is
at focal yellow, and another at focal red. ... We
assume that the names that get assigned to the color
space...are likely to be those names which are most
informative about color [47, p. 312].
This proposal can be seen as a natural generalization of
the universal-foci account, in which every color is focal to
some extent - the extent to which it protrudes from the
irregular outer skin of color space; the originally proposed
universal foci are then simply ‘more focal’ than other colors.
The appeal of the proposal lies in the possibility that
simple principles of categorization, operating over this
irregular surface, might account for both the universal
tendencies and the deviations from them that we see in
the world’s languages. Regier, Kay & Khetarpal [48]
formalized this idea and tested it against the WCS data.
They defined a well-formedness measure that captures the
extent to which a given categorical partition of the outer
skin of color space maximizes perceptual similarity within
color categories and minimizes it across categories [49].
Given this, they created theoretically optimal color naming
systems for n=3,4,5,6 categories, through steepest ascent
in well-formedness. The results are shown in Figure 4,
compared with selected color naming systems in the WCS.
This demonstrates that some languages have color naming
systems that are near optimal in this sense [cf. 50].
While other languages deviated considerably from these
templates, across the languages of the WCS there was a
strong tendency for color naming to be shaped in part by
well-formedness. Specifically, for each language in the
WCS, rotated variants were created as in Figure 3(a),
and for 82 of the 110 WCS languages the unrotated system
was more well-formed than any rotated variant –thus
Figure 3.(a) The Berinmo color naming system (top) unrotated, and rotated four (middle) and eight (bottom) hue columns. Each colored region denotes the extensionofa
named color category, against a standard color naming grid. (b) Boundary match between each version of Berinmo, including the unrotated version, and WCS languages
overall. For each version of Berinmo, the dot shows the mean boundary match with all WCS languages, and the bar shows the 95% confidence interval of the mean. Source:
[39].
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well-formedness provides an explanation for universal
tendencies. At the same time, this account also suggests
where linguistic convention might get some wiggle room.
There are often several similar but different partitions that
are roughly equally well-formed. Hence, local factors, in-
cluding arbitrary linguistic convention, might select from
among a group of highly-ranked systems that differ some-
what from each other - such as Berinmo and Himba. This
recent account suggests a middle ground between nature
and nurture in color naming across languages, and high-
lights another sense in which Whorf might have been half
right.
A competing explanation holds that color naming pat-
terns reflect the statistical distribution of colors in the
world, rather than the shape of perceptual color space in
our minds. Yendrikhovskij [51] showed that k-means clus-
tering of colors obtained from images of natural scenes
produced color clusters similar to those observed in the
world’s languages. Is color naming shaped by exogenous
color diet, or by endogenous perceptual structure? The two
explanations might be partially reconcilable. Shepard
[52,53] argued that universal aspects of perceptual-cogni-
tive structure might correspond to invariants in the
environment, internalized over the course of evolution
[cf. 54]. Thus, it is possible that color naming reflects
the structure of perceptual color space in our minds - which
in turn reflects the distribution of colors in the world.
There is an obvious fact that our discussion so far has
not engaged: color naming systems are used for the social
process of communication about color, and they are passed
on socially from one generation to the next within a speech
community. What is the role of such social forces in
accounting for patterns of color naming? This question
has been increasingly addressed recently, often in agent-
based simulations [55–61]. For example, Steels and Bel-
paeme [55] argued on the basis of such simulations that
color categories might in principle reflect both perceptual
structure and social coordination through language; Dow-
man [57] accounted for patterns of color naming in the
world’s languages in broadly similar terms, through cul-
tural evolution in an idealized color space; and Komarova
et al.[58] show that, given certain simple assumptions, a
population of agents communicating about color will con-
verge to a system of near-optimal color categories.
Of particular interest in such simulations is the ques-
tion of how much explanatory force is carried by social
coordination and transmission per se, and how much by the
individual agents’ biases and expectations concerning the
color domain. In other words, how much of the explanation
lies between individuals, and how much within individ-
uals? A possible answer is suggested by some recent work
by Griffiths and Kalish [62]. They presented a Bayesian
analysis of the social transmission of language, and showed
that under certain assumptions, this process converges to a
distribution over languages that reflects the shared prior
bias of each learner in the social chain. Thus, the eventual
effect of socially transmitting language across generations
is that language itself takes on the form of the learning bias
in each learner’s mind; in the case of color naming, this
would be our prior expectations concerning the shape of
color categories. And as argued above, this mental struc-
ture might in turn reflect invariants in the distribution of
colors in the world. Taken as a whole, such an account
might help to explain the success of some models that are
based on color diet, or on the mental representation of
color, with no social component at all: environmental
Figure 4. Theoretical optima (left) for n=3,4,5,6categories, compared withcolor naming systems (right,top to bottom) of Ejagam (Nigeria/Cameroon),Culina (Peru/Brazil), Iduna
(Papua New Guinea), Buglere (Panama). All results mapped against a standard color grid, in which columns denote hues and rows denote lightness levels. Source:[48].
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structure might be internalized in the mind over evolution-
ary time, and then externalized in the form of language
through iterated social transmission, with the result that
models capturing this structure either in the environment,
or in the mind, can fit color naming data well. At the same
time, there are insights that seem less likely to be easily
capturable in these terms. For example, Jameson and
Komarova [61] examined agent populations in which not
all agents had the same biases, capturing various mixtures
of normal and anomalous color vision. They concluded that
a rather small percentage of agents with anomalous color
vision could greatly affect the color category boundaries of
the population - suggesting a possible explanation for some
of the cross-language variation observed.
Conclusion
We have reviewed two broad recent findings here: that
language affects color perception primarily in the right
visual field probably via activation of language regions of
the left hemisphere, and that color naming reflects both
universal and local determinants. Neither of these findings
is anticipated by the traditional universalist-versus-rela-
tivist framing of the debate over language and perception,
and neither sits particularly comfortably with it. Instead,
these findings suggest novel perspectives on the relation of
language and perception. There is some evidence already
available that these findings generalize to domains beyond
color. The replication of the initial results on the latera-
lized Whorf effect in color [8,9] to dog and cat silhouettes
[12] indicates that RVF-lateralized categorical perception
might not be restricted to the color domain (and ongoing
research suggests that optimization of well-formedness
might generalize to the spatial domain). Just which of
the findings reported here for color will generalize to other
domains of language or to cognition more broadly, and
which are restricted to color, should furnish significant
research questions in the future.
Acknowledgments
This work was supported by NSF grants 0418283 (to TR) and 0418404 (to
PK).
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