Content uploaded by Harold Odden
Author content
All content in this area was uploaded by Harold Odden
Content may be subject to copyright.
Research Article
Synchrony in the Onset of
Mental-State Reasoning
Evidence From Five Cultures
Tara Callaghan,
1
Philippe Rochat,
2
Angeline Lillard,
3
Mary Louise Claux,
4
Hal Odden,
2
Shoji Itakura,
5
Sombat Tapanya,
6
and Saraswati Singh
7
1
St. Francis Xavier University, Antionish, Nova Scotia, Canada;
2
Emory University;
3
University of Virginia;
4
Catholic
University of Peru, Lima, Peru;
5
Kyoto University, Kyoto, Japan;
6
Chiang Mai University, Chiang Mai, Thailand; and
7
M.K.P. College, Dehradun, India
ABSTRACT—Over the past 20 years, developmental psy-
chologists have shown considerable interest in the onset of
a theory of mind, typically marked by children’s ability to
pass false-belief tasks. In Western cultures, children pass
such tasks around the age of 5 years, with variations of the
tasks producing small changes in the age at which they are
passed. Knowing whether this age of transition is common
across diverse cultures is important to understanding
what causes this development. Cross-cultural studies have
produced mixed findings, possibly because of varying
methods used in different cultures. The present study used
a single procedure to measure false-belief understanding
in five cultures: Canada, India, Peru, Samoa, and Thai-
land. With a standardized procedure, we found synchrony
in the onset of mentalistic reasoning, with children cross-
ing the false-belief milestone at approximately 5 years of
age in every culture studied. The meaning of this syn-
chrony for the origins of mental-state understanding is
discussed.
A major social-cognitive achievement of young humans is the
understanding that people act on the basis of their represen-
tations of reality, rather than reality itself. For more than 20
years, developmental psychologists have explored the onset and
refinement of this psychological understanding in children
under the rubric theory of mind (Premack & Woodruff, 1978).
The basic question in this research is how children come to take
the mental state of other individuals into account when making
judgments about their overt behavior. Appreciation of the effect
of false belief on behavior is taken to be the strongest indicator
that children have achieved this insight (Dennett, 1978). In a
seminal study by Wimmer and Perner (1983), children heard a
story about a doll who put chocolate in location A and then went
out of the room, at which point the chocolate was moved to lo-
cation B. The children were asked where the doll would look for
the chocolate upon returning. A majority of 5-year-olds passed
(i.e., said the doll would look in the original location), and all of
the 3-year-olds failed (i.e., said the doll would look in the new
location). Consistent findings have been obtained with altered
versions of the false-belief task, confirming that the funda-
mental shift in understanding the impact of the mind on be-
havior occurs between the ages of 3 and 5 years in European and
North American children (Wellman, Cross, & Watson, 2001).
Such reasoning reflects what is generally viewed as the hu-
man ability to represent the mental world of other individuals by
age 5, and to learn by taking others’ perspectives (Tomasello,
Kruger, & Ratner, 1993). Research with autistic individuals
(Baron-Cohen, 1995) suggests a biological mechanism for the
onset of mentalistic reasoning because even when their mental
age is over 6 years, they still fail false-belief tasks. Finding a
small age window during which children universally develop an
understanding of false beliefs could also be taken as evidence
for a biological account, although it would leave open the
question of whether culturally universal childhood experiences
are necessary triggers for such understanding. We consider this
issue in the General Discussion.
Very few cross-cultural studies have investigated mental-
state reasoning, and most of these have looked at only a single
non-Western culture or varied in methodology, making cultural
comparisons difficult. The cultural appropriateness of a verbal
task posing questions about hypothetical characters is also a
Address correspondence to Tara Callaghan, Psychology Department,
St. Francis Xavier University, P.O. Box 5000, Antigonish, N.S.,
Canada B2G 2W5; e-mail: tcallagh@stfx.ca.
PSYCHOLOGICAL SCIENCE
378 Volume 16—Number 5Copyright r2005 American Psychological Society
recurring problem in these studies, even when careful attempts
are made to make the language in the non-Western cultural
setting comparable to the language used in the original study.
In one such cross-cultural study, Vinden (1996) attempted to
measure mentalistic reasoning in Quechua-speaking children
in the highlands of Peru using a false-belief location task
modeled on Perner, Leekham, and Wimmer’s (1987) hidden-
chocolate story, as well as two other theory-of-mind tasks (a
deceptive container task after Gopnik & Astington, 1988, and
an appearance-reality task following Flavell, Flavell, & Green,
1983). Although the tasks were conducted by a native Que-
chuan collaborator who was known to the children, and although
Vinden took care to provide a meaningful translation of the task,
the children, who were 4 to 8 years old, performed poorly on all
tasks. Either Junin Quechua children truly do not understand
false belief even by age 8 or the task did not translate into their
culture.
An earlier study by Avis and Harris (1991) used a more
culturally natural version of the false-belief task with preliterate
children (Baka of southeast Cameroon) and found that the
children passed at an age comparable to that seen in European
and North American studies. In Avis and Harris’s modified task,
children engaged in what appeared to be a real situation of
deception involving two confederates who were members of
their community. One confederate made a special meal in a hut
used for cooking, while the other confederate sat with the child.
The cook announced how much he liked the food and that he
would be right back to eat it as soon as he had visited in the male
meeting place. When he left, the second confederate asked the
child to play a game by hiding the food. When the child did this,
he or she was asked to predict where the first confederate would
look for it, and how he would feel before and after discovering
the missing food. This task modification required the child to
reason about the mental state of the deceived person, but may
have made that reasoning easier by having the scenario acted
out with real people in what appeared to be a real situation,
rather than by using the typical puppets and stories.
A second study by Vinden (1999) adapted Avis and Harris’s
(1991) task for four cultural groups: Western children (of Eu-
ropean descent, attending a missionary school in Papua New
Guinea), Mofu schooled children (from northern Cameroon,
attending French immersion schools), Tolai schooled children
(from Papua New Guinea, attending English preparatory
schools), and Tainae nonschooled children (from a remote
jungle village in Papua New Guinea). Children in all four groups
appeared to pass the task by 6 to 7 years. However, it is difficult
to assess the developmental trajectory for these children be-
cause very few were younger than 6 years, and the task included
additional questions about thoughts and feelings that may have
created difficulties. Perhaps the most interesting finding was
that the 6 children in the youngest age category (4–8 years) from
the most remote, preliterate setting (Tainae) passed the false-
belief question about where the person would look. This finding
corroborates the high passing rate for this question reported for
preliterate 5-year-old children by Avis and Harris.
In a third study, Vinden (2002) compared schooled and
nonschooled Mofu children on a battery of theory-of-mind
questions, including location false-belief questions and 11
other questions related to prior and subsequent true and false
beliefs. Although schooling did not influence performance on
the false-belief test, schooled children had better overall scores
on the battery of questions. Because the schooled children in
this study received second-language immersion (French), it is
difficult to determine whether it was schooling or bilingualism
that accounted for their higher overall scores.
In sum, although most research that is relevant to an under-
standing of the development of mentalistic reasoning has been
conducted in Western cultures, there are a few notable excep-
tions. When researchers (Avis & Harris, 1991; Vinden, 1999,
2002) have used a naturalistic procedure in which non-Western
children participate in deceiving a familiar person, their per-
formance has appeared to approximate that of Western children.
However, in these studies, sample sizes have been small, only a
limited number of cultures have been examined, and tasks have
varied across cultures. When a natural procedure has not been
used, there has been a discrepancy of 2 years in the estimated
age of onset of this ability across cultures (Vinden, 1996). A
more extensive and controlled study is needed to make a
stronger case for synchrony of onset of mental-state reasoning
across cultures. The present article reports such a study, in
which we used a single simplified version of the naturalistic task
with 3- to 5-year-old children from five diverse cultural settings
(Canada, Peru, India, Thailand, and Samoa).
METHOD
Cultural Contexts
The research was conducted in five cultural settings: Canada,
Peru, Samoa, India, and Thailand. In Canada, children from a
rural town having a middle-income socioeconomic level and a
variety of private early education programs were tested in a
quiet room in their preschool. Classroom groupings in this
preschool included approximately 12 children, led by one
teacher and one assistant. Children in this preschool were fa-
miliar with researchers and teachers conducting special tasks
with them in individual settings, and thus are similar to children
sampled in previous research.
In Peru, children from a rural Andean town were tested. So-
cioeconomic levels were low relative to Peruvian standards, but
private and public early education programs were common.
Children were tested in their preschools, where one teacher,
assisted by one or two aides, was in charge of each group of
approximately 25 children. These children rarely received in-
dividual attention from teachers, and when they did, it was
usually within the classroom. Although children in these Pe-
ruvian schools were typically administered tests in a group
Volume 16—Number 5 379
T. Callaghan et al.
setting, children nevertheless showed a willingness to play the
game individually with the two researchers, who were intro-
duced as ‘‘teachers.’’
In Samoa, children from traditional Polynesian agrarian vil-
lages governed through a chief (matai) system were tested in
preschools or their homes. Preschools sponsored by local
churches are becoming more common in Samoa, although many
young children are still cared for by an extended family group.
The socioeconomic status of these villages was typical ac-
cording to standards in Samoa, where wealth is communal,
shared according to the traditional matai system. Although
separate rooms were not available because of the open design of
buildings, we successfully secluded the children during testing,
in both preschool and home settings, so that other children who
would subsequently be tested could not observe or interfere
with the procedure. As were the Peruvian children, the Samoan
children were unfamiliar with special, individualized tasks in
an educational setting.
In India, children from a populous city were tested in their
highly formal and regimented private schools, each of which
went from primary grades through high school. The socioeco-
nomic status of the sample was middle to upper middle class by
Indian standards. In this community, children attended school
from the age of 3 years. Classroom groups generally included
approximately 30 to 40 children, with 3- to 4-year-olds and 5-
year-olds in separate groups. These children were familiar with
formal testing by an adult, but this was usually accomplished in
group settings. Each group was headed by one teacher and one
assistant, who were responsible for instruction and testing. For
this study, children were tested in the false-belief task in a quiet
room or hallway outside of their classrooms.
In Thailand, children were tested in a Buddhist temple school
for disadvantaged children in a large Thai city. Socioeconomic
status of the sample was low by Thai standards, even though the
school was in the relatively affluent university neighborhood.
Preschools and day-care centers were common in this city, but
this preschool was unusual in targeting children who were
economically disadvantaged. Relations between teachers and
students were respectful, but relaxed and friendly. Typically,
one teacher and two assistants were assigned to each class of
about 40 preschoolers. Instruction was delivered in group set-
tings, and individualized testing and attention were rare. These
children were tested in hallways or rooms adjacent to their main
classroom.
Experimenters
In all settings, the children were tested by two female experi-
menters. In Canada, the experimenters were research assistants
with prior experience conducting research with children. Ca-
nadian-trained research assistants traveled to the other loca-
tions to train local collaborators. In Peru, Samoa, and Thailand,
the Canadian researcher served as the deceived adult (see
Procedure), and the local assistant took on the other role, en-
couraging the child to play a game on the other researcher. In
India, two local assistants played these roles.
Participants
The final sample included 267 children between the ages of 30
to 72 months. For statistical analyses, children from Canada,
India, Samoa, and Peru were grouped into three ages (3, 4, and 5
years). Children were considered 3-year-olds if they were be-
tween their third and fourth birthdays, 4-year-olds if they were
between their fourth and fifth birthdays, and 5-year-olds if they
were between their fifth and sixth birthdays. Children from
Thailand were grouped into 3-year-olds and 5-year-olds (no 4-
year-olds were tested). For all Thai children, and some Samoan
children (13 out of 72), it was necessary to estimate children’s
ages through discussions with parents and teachers because
accurate birth-date information was not kept. Mean ages were
3.7, 4.5, and 5.3 years for the Canadian age groups; 3.5, 4.5, and
5.4 years for the Peruvian age groups; 3.5, 4.5, and 5.6 years for
the Indian age groups; 3.6, 4.4, and 5.2 years for the Samoan age
groups (excluding children with estimated ages); and 3.3 and
5.0 years for the Thai age groups (estimated).
Procedure
A false-belief task involving location was used in all settings.
This task, a simplification of the naturalistic task used by other
researchers (Avis & Harris, 1991; Vinden, 1999), involved an
experimenter hiding a trinket under one of three bowls, then
leaving the room. Whereas Vinden (1999) and Avis and Harris
(1991) asked about a person’s thoughts, emotions, and behavior
in response to a false-belief situation, we asked only about
behavior. Such a strategy minimizes issues of translation and
cultural mores (such as it not being acceptable to discuss other
people’s mental states, see Lillard, 1998). Local collaborators
translated the script, taking care that the tone and wording
corresponded to typical adult-child friendly interactions in
their respective cultural settings.
First, the experimenter showed the child the trinket (e.g.,
ring, coin), which was chosen to be attractive to children, and
commented on how it was her favorite toy. She then said, ‘‘I’m
going to hide my toy under here while I go to _______ [an errand
was invented],’’ as she placed the toy under one of the bowls.
Before leaving the room, the experimenter lifted the bowl and
said, ‘‘See, it’s right there. I’m going to play with it when I get
back.’’ The experimenter then left the room. At this time, the
second experimenter asked the child, ‘‘Do you want to play a
game on _______ [the other experimenter’s name]? Take the toy
and hide it under another bowl.’’ She waited for the child to act,
and if the child did not, she indicated one of the bowls and said,
‘‘Hide it under here.’’ If the child still did not act, the experi-
menter moved it and said, ‘‘See, I’ve moved it to this bowl,’’ as
she lifted the bowl to show the toy. Once the trinket was moved,
380 Volume 16—Number 5
Onset of Mental-State Reasoning
the child was asked, ‘‘Where is _________ going to look for her
toy when she comes back?’’
Children indicated their choice by pointing. All sessions were
videotaped and later checked for reliability. Fourteen children
out of the initial sample (N5281) were excluded because of
procedural errors (6 cases) and response ambiguity (8 cases).
For the remaining 267 children, there was 100% agreement for
response coding. As in traditional false-belief location tasks, a
child was scored as having passed the task if he or she pointed to
the location where the experimenter who left the room had
hidden her trinket, and as having failed if he or she pointed to
the location where the trinket was moved in that experimenter’s
absence.
RESULTS
Separate sign tests were conducted on the pass/fail frequency
data from each culture, as well as on these data combined across
cultures. Table 1 presents the data along with the probability
levels for the sign tests. From the table, it is evident that in all
five settings, a majority of 3-year-olds failed the false-belief task
(all ps<.05), and a majority of 5-year-olds passed (all ps<.01
except in Samoa, where p<.10). In all settings except Samoa,
where most 4-year-old children failed ( p<.05), 4-year-olds
were fairly evenly split between those who failed and those who
passed the task (all pvalues were not significant). The data for
individual cultures are mirrored in the data combined across
cultures. Sign tests of the combined data revealed that the
majority of 3-year-old children failed the task ( p<.001),
approximately equal numbers of 4-year-old children failed
and passed (n.s.), and a majority of 5-year-old children passed
(p<.001).
In addition to conducting statistical analyses, we plotted the
percentage of children passing the false-belief task as a func-
tion of age in order to provide a visual representation of the
trends. To obtain an accurate plot of the developmental tra-
jectory as a function of age in months, we did not include in
these graphs the children for whom we estimated ages. For each
culture, data were ordered by age and then clustered into 10-
children groups starting with the youngest child (there were 9,
4, 1, and 2 children in the last cluster for the Samoan, Indian,
Peruvian, and Canadian samples, respectively). For each of the
age clusters, the percentage of children who passed the test was
calculated; these results are plotted in the upper panel of Figure
1. To plot the data combined across all cultures, we grouped the
data into the following age clusters: 30–36 months, 36–42
months, 42–48 months, 48–54 months, 54–60 months, 60–66
months, and 66–72 months. Within each of these age clusters,
the percentage of children who passed the false-belief task was
calculated; these results are plotted in the bottom panel of
Figure 1. The graphs clearly show that for both individual
cultures and the combined data across cultures, there was a
shift from failure to success on the false-belief location task
between the ages of 3 and 5 years.
GENERAL DISCUSSION
These results align with findings from studies using a variety of
procedures with European and North American children
(Wellman et al., 2001), as well as with the findings from studies
using the same modified procedure with preliterate Baka and
Tainae children (Avis & Harris, 1991; Vinden, 1999). Including
the present study with these previous ones, children in Euro-
pean, North American, Latin, Asian, African, and Polynesian
cultures have been sampled, as have schooled children (the
majority of research) and nonschooled children (Avis & Harris,
1991; Vinden, 1999, 2002). The fundamental shift in under-
standing the impact of a false belief on behavior appears to be a
universal milestone of development that occurs between 3 to 5
years of age. Synchrony in the age at which children of diverse
cultures pass the false-belief task undermines the claim that
particular cultural views, such as a Western concept of mind,
profoundly influence this very basic aspect of early mental-state
reasoning, and strengthens a claim of universality. Whether the
synchrony results more from biological maturation or from ex-
periences that are universal across the cultures sampled, or
both, remains at issue.
TABLE 1
Number of Children Passing and Failing the False-Belief Task for Each Culture and Age Group
Culture
Age group
3 years 4 years 5 years
Pass Fail pPass Fail pPass Fail p
Peru 4 27 <.001 12 14 n.s. 20 3 <.001
India 5 15 <.05 11 6 n.s. 14 3 <.01
Samoa 2 14 <.01 7 18 <.05 13 5 <.10
Thailand 1 16 <.001 — — — 12 1 <.01
Canada 2 11 <.01 9 8 n.s. 13 1 <.001
Overall 14 83 <.001 39 46 n.s. 72 13 <.001
Note. The pvalues indicate the probability levels of sign tests.
Volume 16—Number 5 381
T. Callaghan et al.
If biological maturation is the main factor responsible for the
onset of false-belief understanding, then different cultural ex-
periences would not have tremendous impact on the age of
onset. An analogous situation is learning to walk. Children the
world over learn to walk at around 1 year of age, although one
can hasten this achievement, as the Kipsigis do, by providing
experiences that strengthen the legs (Super, 1976) or slow it by
providing ‘‘walker’’ experiences that might reduce the child’s
drive to walk (Garrett, McElroy, & Staines, 2002). A biological-
maturation account is consistent with the evidence accrued thus
far, including synchrony in the onset of false-belief under-
standing across cultures. Children with autism develop false-
belief understanding very late, and possibly by different
mechanisms than other children (Baron-Cohen, 1995; Leslie &
Roth, 1994). Children with older siblings (Perner, Ruffman, &
Leekham, 1994; Ruffman, Perner, Naito, Parkin, & Clements,
1998), children who engage in more pretend role play (Lillard,
2002), and children whose parents talk about mental states
more understand false belief earlier than other children, but not
much earlier (Ruffman, Slade, & Crowe, 2002), and children
from low-income homes develop the understanding later than
other children, but not much later (Holmes, Black, & Miller,
1996).
The one exception to this universality in the age of onset is the
case of deaf children. Deaf children are delayed in false-belief
understanding, even into the teen years (Peterson & Siegal,
1995). However, this delay is particular to deaf children who are
late signers and whose parents are not deaf (Figueras-Costa &
Harris, 2001; Lundy, 2002; Remmel, 2003; Woolfe, Want, &
Siegal, 2002). Because deaf children are not thought to have
impairments in the particular brain circuitry that appears to be
involved in false-belief reasoning (Frith & Frith, 1999), this
finding raises the issue of whether there are experiences that
contribute crucially to its development, and what those expe-
riences are. The synchrony of onset of false-belief under-
standing across cultures demonstrated in the present study
could be more the result of common experiences across the
cultures, or cultural universals, than of biological maturation.
One candidate common experience is schooling. When
children are in school, they interact with children from different
families and with a teacher, and this interaction might create
new pressures, beyond those felt at home, to develop false-be-
lief understanding. Children in all the samples in the present
study were in school programs, so the present evidence cannot
be definitive regarding the impact of schooling. However, in the
only study to directly compare schooled and nonschooled
(Mofu) children, Vinden (2002) reported no effect of schooling
on false-belief understanding. These findings support those
reported by Avis and Harris (1991) in their study of nonschooled
Baka children, who showed onset of false-belief understanding
at around 5 years. Schooling may help to refine understanding
of false belief, but is not necessary for the onset of this under-
standing.
An alternative candidate experience, raised particularly with
regard to deaf children, is conversation. Conversation both
brings other individuals’ mental views to light and brings a
vocabulary necessary to the transaction of mental states. All
children except deaf ones who do not sign are exposed to con-
versation throughout their lives. Perhaps passing false-belief
tasks requires a certain amount of experience hearing and
participating in conversations in which mental states are
shared. This would make sense in terms of the findings on slight
variations in the onset of false-belief understanding: Children’s
need to discuss mental states and exposure to mental-state
conversations increase the more other children (siblings) there
are in their environment; children discuss mental states fre-
quently in the context of pretend role play; and children
from low-income families experience less talk in the home
than do children from higher-income families (Hart & Risley,
1995).
Other precursor abilities probably also play a role, both in
promoting conversation and in making children aware of mental
states. Certain social-cognitive accomplishments of infancy,
including joint attention, social referencing, imitation (Toma-
sello, 1999a, 1999b), and understanding of intentional action
(Gergeley, Bekkering, & Kiraly, 2002; Rochat, Morgan, &
Fig. 1. Percentage of children passing the false-belief test as a function of
age. In the top panel, data are plotted separately for Canada, Samoa,
India, and Peru. In the bottom panel, results for these four cultures are
combined. Data from 13 Samoan and all Thai children were excluded
from this analysis because their birth dates were not available.
382 Volume 16—Number 5
Onset of Mental-State Reasoning
Carpenter, 1997; Tomasello & Haberl, 2003; Woodward, 1998)
have been proposed as precursors to theory-of-mind under-
standing (Tomasello, 1999b; Wellman, 1994). These skills,
developed through maturation and social experience, might
work with conversation to assist children in developing an un-
derstanding of the mental lives of other individuals.
Synchrony in the age of onset of mental-state reasoning does
not preclude diversity in outcome. Our findings support the view
of Avis and Harris (1991), who suggested that adults and chil-
dren may have access to a universal understanding of belief-
desire psychology even though they may come to elaborate this
understanding differently, depending on their culture’s prac-
tices. The precise nature of such elaborations and how they
develop from early understanding is a theme that needs to be
addressed in future research. The present study establishes the
existence of a common starting point for the very fundamental
understanding that actions are based on representations of re-
ality. We agree with other researchers (Avis & Harris, 1991;
Harris, 1990) who have suggested that reasoning on the basis of
inferred belief systems is merely the beginning foundation of
psychological understanding that is later supplemented with
more complex forms of mental-state reasoning and with cul-
turally specific principles of the causes of human action (Lil-
lard, 1998). The sophisticated theories of mind held by adults in
the cultures studied by these researchers, as well as in other
cultures, are rich in their diversity, and the refinement of early
fundamental understanding to later sophisticated nuance is
undoubtedly the work of cultural influence.
Although we have focused on one ubiquitous milestone of
human cognition, we suggest that the social-cognitive precur-
sors we mentioned earlier in this section may demonstrate
synchronous onset as well. There may also be universal mile-
stones of mentalistic reasoning that occur later in development.
Harris (Gardner, Harris, Ohmoto, & Hamazaki, 1988; Harris &
Gross, 1988) reported that the age at which children first un-
derstand the distinction between real and apparent emotion is
similar for American, British, and Japanese children. In order to
determine the nature of any universal core understanding of
mind, it would be informative to determine whether synchro-
nous developmental trends, such as the one reported here for
the onset of false-belief understanding, are also characteristic of
both precursors and refinements to theories of mind by exam-
ining milestones of social cognition from infancy through
childhood across diverse cultural settings.
Acknowledgments—This research was supported by Social
Sciences and Humanities Research Council of Canada–Re-
search Development Initiatives and Human Resources Devel-
opment Canada. We thank the many research assistants, teachers,
children, and parents in the cultures where we conducted
the research, and the Canadian field research interns.
REFERENCES
Avis, J., & Harris, P.L. (1991). Belief-desire reasoning among Baka
children: Evidence for a universal conception of mind. Child
Development,62, 460–467.
Baron-Cohen, S. (1995). Mindblindness: An essay on autism and theory
of mind. Cambridge, MA: MIT Press.
Dennett, D.C. (1978). Beliefs about beliefs. Behavioral and Brain
Sciences,1, 568–570.
Figueras-Costa, B., & Harris, P. (2001). Theory of mind development in
deaf children: A nonverbal test of false-belief understanding.
Journal of Deaf Studies & Deaf Education,6(2), 92–102.
Flavell, J., Flavell, E., & Green, F. (1983). The development of
the appearance-reality distinction. Cognitive Psychology,15,
95–120.
Frith, C.D., & Frith, U. (1999). Interacting minds—a biological basis.
Science,286, 1692–1695.
Gardner, D., Harris, P.L., Ohmoto, M., & Hamazaki, T. (1988). Un-
derstanding of the distinction between real and apparent emotion
by Japanese children. International Journal of Behavioral De-
velopment,11, 203–218.
Garrett, M., McElroy, A.M., & Staines, A. (2002). Locomotor mile-
stones and babywalkers: A cross sectional study. British Medical
Journal,324, 1494.
Gergeley, G., Bekkering, H., & Kiraly, I. (2002). Rational imitation in
preverbal infants. Nature,415, 755.
Gopnik, A., & Astington, J. (1988). Children’s understanding of rep-
resentational change and its relation to the understanding of false
belief and the appearance-reality distinction. Child Development,
59, 26–37.
Harris, P.L. (1990). The child’s theory of mind and its cultural context.
In G. Butterworth & P. Bryant (Eds.), Causes of development:
Interdisciplinary perspectives (pp. 215–237). Hillsdale, NJ: Erl-
baum.
Harris, P.L., & Gross, D. (1988). Children’s understanding of real and
apparent emotion. In J.W. Astington, P.L. Harris, & D.R. Olson
(Eds.), Developing theories of mind (pp. 295–314). Cambridge,
England: Cambridge University Press.
Hart, B., & Risley, T. (1995). Meaningful differences in the everyday
experience of young American children. Baltimore: Brookes.
Holmes, H.A., Black, C., & Miller, S.A. (1996). A cross-task com-
parison of false belief understanding in a Head Start popula-
tion. Journal of Experimental Child Psychology,63, 263–285.
Leslie, A.M., & Roth, D. (1994). What autism tells us about meta-
representation. In S. Baron-Cohen, H. Tager-Flusberg, & D.
Cohen (Eds.), Understanding other minds: Perspectives from au-
tism (pp. 83–111). Oxford, England: Oxford University Press.
Lillard, A. (1998). Ethnopsychologies: Cultural variations in theories
of mind. Psychological Bulletin,123, 3–32.
Lillard, A. (2002). Pretend play and cognitive development. In U.
Goswami (Ed.), Blackwell handbook of cognitive development (pp.
188–205). London: Blackwell.
Lundy, J.E.B. (2002). Age and language skills of deaf children in
relation to theory of mind development. Journal of Deaf Studies
& Deaf Education,7(1), 41–56.
Perner, J., Leekham, S.R., & Wimmer, H. (1987). Three-year-
olds’ difficulty with false belief: The case for a conceptual deficit.
British Journal of Developmental Psychology,5, 125–137.
Perner, J., Ruffman, T., & Leekham, S.R. (1994). Theory of mind is
contagious: You catch it from your sibs. Child Development,65,
1228–1238.
Volume 16—Number 5 383
T. Callaghan et al.
Peterson, C.C., & Siegal, M. (1995). Deafness, conversation and theory
of mind. Journal of Child Psychology and Psychiatry and Allied
Disciplines,36, 459–474.
Premack, D., & Woodruff, G. (1978). Does the chimpanzee have a
theory of mind? Behavioral and Brain Sciences,1, 515–526.
Remmel, E.R. (2003). Theory of mind development in signing deaf
children. Dissertation Abstracts International: B. The Physical
Sciences and Engineering,64 (3-B), 1526. (UMI No. AAI 3085361)
Rochat, P., Morgan, R., & Carpenter, M. (1997). Young infants’ sensi-
tivity to movement information specifying social causality. Cog-
nitive Development,12, 441–465.
Ruffman, T., Perner, J., Naito, M., Parkin, L., & Clements, W.A. (1998).
Older (but not younger) siblings facilitate false belief under-
standing. Developmental Psychology,34, 161–174.
Ruffman, T., Slade, L., & Crowe, E. (2002). The relation between
children’s and mother’s mental state language and theory of mind
understanding. Child Development,73, 734–751.
Super, C.M. (1976). Environmental effects on motor development:
The case of African infant precocity. Developmental Medicine &
Child Neurology,18, 561–567.
Tomasello, M. (1999a). The cultural origins of human cognition.
Cambridge, MA: Harvard University Press.
Tomasello, M. (1999b). Having intentions, understanding intentions,
and understanding communicative intentions. In P. Zelazo, J.W.
Astington, & D. Olson (Eds.), Developing theories of intentionality:
Social understanding and self-control (pp. 63–75). Mahwah,
NJ: Erlbaum.
Tomasello, M., & Haberl, K. (2003). Understanding attention: 12- and
18-month-olds know what is new for other persons. Developmental
Psychology,39, 906–912.
Tomasello, M., Kruger, A., & Ratner, H. (1993). Cultural learning.
Behavioral and Brain Sciences,16, 495–552.
Vinden, P. (1996). Junin Quechua children’s understanding of mind.
Child Development,67, 1707–1716.
Vinden, P. (1999). Children’s understanding of mind and emotion:
A multi-culture study. Cognition and Emotion,13, 19–48.
Vinden, P. (2002). Understanding minds and evidence for belief: A
study of Mofu children in Cameroon. Journal of International
Behavioral Development,26, 445–452.
Wellman, H.M. (1994). Early understanding of mind: The normal case.
In S. Baron-Cohen, H. Tager-Flusberg, & D. Cohen (Eds.), Un-
derstanding other minds: Perspectives from autism (pp. 10–39).
Oxford, England: Oxford University Press.
Wellman, H.M., Cross, D., & Watson, J. (2001). A meta-analysis of
false belief reasoning: The truth about false belief. Child Devel-
opment,72, 655–684.
Wimmer, H., & Perner, J. (1983). Beliefs about beliefs: Representa-
tion and constraining function of wrong beliefs in young
children’s understanding of deception. Cognition,13, 103–128.
Woodward, A. (1998). Infants selectively encode the goal object of an
actor’s reach. Cognition,69, 1–34.
Woolfe, T., Want, S.C., & Siegal, M. (2002). Signposts to develop-
ment: Theory of mind in deaf children. Child Development,73,
768–778.
(RECEIVED 4/12/04; REVISION ACCEPTED 6/16/04)
384 Volume 16—Number 5
Onset of Mental-State Reasoning