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The Development of Gender Constancy
in Early Childhood and Its Relation to
Time Comprehension and False-Belief
Understanding
Norbert Zmyja & Doris Bischof-Köhlerb
a Ruhr-Universität Bochum, Germany
b LMU Munich, Germany
Accepted author version posted online: 09 Nov 2013.Published
online: 09 Nov 2013.
To cite this article: Norbert Zmyj & Doris Bischof-Köhler (2015) The Development of Gender
Constancy in Early Childhood and Its Relation to Time Comprehension and False-Belief Understanding,
Journal of Cognition and Development, 16:3, 455-470, DOI: 10.1080/15248372.2013.824881
To link to this article: http://dx.doi.org/10.1080/15248372.2013.824881
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The Development of Gender Constancy in Early
Childhood and Its Relation to Time Comprehension and
False-Belief Understanding
Norbert Zmyj
Ruhr-Universita¨t Bochum, Germany
Doris Bischof-Ko¨hler
LMU Munich, Germany
What is the developmental course of children’s gender constancy? Do other cognitive abilities such
as time comprehension and false-belief understanding foster gender constancy and the subcompo-
nents gender stability and gender consistency? We examined the development of gender constancy
and its relation to time comprehension and false-belief understanding in children aged 3 to 6 years
old. A new gender constancy task was designed, consisting of video sequences presenting a boy and
a girl dressing up in clothes typically worn by the opposite sex and playing with toys usually played
with by the opposite sex. Time comprehension was measured by a comparison of three hourglasses
containing different amounts of sand (as in Bischof-Ko¨ hler, 2000). False-belief understanding
was tested with an adaptation of Wimmer and Perner’s (1983) seminal change-of-location task.
Regression analyses revealed that false-belief understanding predicted gender constancy and gender
consistency and that time comprehension predicted gender stability. These relations are discussed
according to task-specific characteristics of gender constancy and a domain-general mechanism
underlying these abilities.
Gender as a social category is omnipresent in children’s lives. Consequently, the development of
the ability to understand the invariance of sex has been intensively investigated. Most research
has been influenced by Kohlberg’s (1966) view of gender role development. Based on Piaget’s
stage theory of cognitive development (Piaget, 1954), Kohlberg argued that until the age of 6 or
7, children are not fully capable of understanding that sex is an invariant characteristic of an
individual. According to Piaget, children at the preoperational stage focus on appearance rather
than on reality and they are not yet able to mentally reverse an observed transformation. As a
consequence, they believe that sex can be changed by a transformation of appearance (e.g.,
by dressing in clothes typically associated with the opposite sex). It has previously been repeat-
edly demonstrated that preschoolers indeed have a problem with gender constancy tasks (Eaton
& von Bargen, 1981; Emmerich, Goldman, Kirsh, & Sharabany, 1977; Marcus & Overton,
1978; Slaby & Frey, 1975; Szkrybalo & Ruble, 1999; Wehren & de Lisi, 1983).
Correspondence should be sent to Norbert Zmyj, Ruhr-Universita¨ t Bochum, Universita¨tsstraße 150, Bochum 44801,
Germany. E-mail: norbert.zmyj@rub.de
JOURNAL OF COGNITION AND DEVELOPMENT, 16(3):455–470
Copyright #2015 Taylor & Francis Group, LLC
ISSN: 1524-8372 print=1532-7647 online
DOI: 10.1080/15248372.2013.824881
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The Development of Gender Constancy
In the following, gender constancy is defined as consisting of three components: a) the ability to
correctly label the sex of another individual (gender labeling), b) the understanding that an
individual’s sex is constant across time (gender stability), and c) the understanding that percep-
tual transformation, such as dressing up like the opposite sex, does not change sex (gender con-
sistency). Children’s understanding of their own gender constancy has usually been assessed by
asking whether the child would change his=her sex if he=she wore opposite-sex clothes, played
opposite-sex games, and wanted to be the opposite sex (Slaby & Frey, 1975). To test children’s
understanding of the gender constancy of other individuals, the questions were additionally
illustrated by schematic drawings of children dressed in opposite-sex clothes and playing
opposite-sex games (Emmerich et al., 1977). However, these methodologies are problematic
for several reasons. Slaby and Frey’s (1975) measure does not test the child’s ability to conserve
sex across a perceptual transformation because no perceptual transformation is provided. Their
purely verbal task could also be rather demanding for younger children whose verbal skills are
limited. Emmerich and colleagues’ (1977) use of schematic drawings had the disadvantage of
having highly artificial stimuli. Thus, children might be prepared to accept that the comic
characters depicted by the schematic drawings can change their sex and at the same time be
aware of the fact that their peers in real life cannot. Bem (1989) improved this procedure by using
photographs of real children. However, the children were repeatedly reminded that this child was
the same child as before he or she ‘‘was playing silly dressing games’’ (Bem, 1989,p.654)while
they looked at the photograph of a protagonist dressed in opposite-sex clothes. Therefore, children
might not have fully executed the perceptual transformation of the child depicted, and therefore,
there was no need for them to reverse the suggested transformation.
Conclusions regarding the onset of gender constancy vary. Some investigators report that
gender constancy is attained during the 4th year of life (Bem, 1989; Lloyd & Stroyan, 1994;
Slaby & Frey, 1975). Other researchers claim that gender constancy does not occur until the
age of 6 or 7 years old (de Lisi & Gallagher, 1991; Emmerich et al., 1977; Wehren & de Lisi,
1983). This variance might be influenced by the particular version of the gender constancy task.
That is, children tend to perform better when purely verbal methods are applied in contrast to
measures using schematic drawings (Martin & Halverson, 1983). Furthermore, when questions
include the term ‘‘really’’ (e.g., ‘‘What is Gaw really—a boy or a girl?’’; Bem, 1989, p. 654),
children’s performance is better than it is without this auxiliary (Slaby & Frey, 1975; Trautner,
Gervai, & Nemeth, 2003).
The Relation Between Gender Constancy and False-Belief Understanding
Kohlberg (1966) suggested that the development of gender constancy coincides with cognitive
maturation, and this assumption has received empirical support. Children’s ability to conceive
of a person’s gender as constant—even if this person behaves and looks like someone of the
opposite sex—correlates with their performance in a conservation task (Marcus & Overton,
1978). Following this line, we hypothesize that gender constancy is associated with theory-of-
mind development. There are different definitions of theory of mind, which include different
assumptions about the level of representing mental processes. Some researchers assume that
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1-year-olds understand key aspects of theory of mind such as false beliefs (Baillargeon, Scott, &
He, 2010). In every study on early false-belief understanding, infants observe goal-directed
actions of a person such as gazing, leaning forward, or reaching, and conclusions are drawn
about their response to such behavior. A rich interpretation is that infants infer the person’s
belief from this situation (e.g., Buttelmann, Carpenter, & Tomasello, 2009). A leaner interpret-
ation, however, is that infants apply a behavioral rule that the person will act on a location to
where he has directed the last goal-directed action (Bischof-Ko¨hler, 2012; Perner, 2010; Sodian,
2011). We favor the idea that theory of mind necessarily entails the ability to acknowledge the
representational nature of an individual’s mental state and not only a sensitivity toward others’
mental states. By means of theory of mind, one conceptualizes cognition such as perception and
beliefs as the result of mental acts. This insight into human cognition allows the simultaneous
representation of the fact that different individuals might perceive one and the same fact differ-
ently depending on their perspective (Clark, 1997; Flavell, 1988; Perner, 1991).
This developmental shift of the concept of mind has been demonstrated in different domains
in 4-year-olds, but it is not yet present in 1-year-olds. Wimmer and Perner (1983) proposed that
children at 4 years of age understand that they themselves and others might hold and even act on
false beliefs. Although task variations slightly alter the age at which children pass these kinds of
task (for a meta-analysis, see Wellman, Cross, & Watson, 2001), the 4th birthday is still con-
sidered a hallmark in the development of false-belief understanding (Flavell, 2004). Four-year-
olds also develop the ability to distinguish between appearance and reality (Flavell, Flavell, &
Green, 1983), although there might be precursors of this ability at age 3 (Moll & Meltzoff,
2011). They also acknowledge that visual experiences of two individuals might differ if their
viewing circumstances differ (Flavell, Everett, Croft, & Flavell, 1981). Furthermore, at around
4 years of age, there is a marked increase in children’s use and understanding of deceptive
strategies (Avis & Harris, 1991; Nelson, Adamson, & Bakeman, 2012; Russell, Mauthner,
Sharpe, & Tidswell, 1991; Sodian, 1991). Different aspects of theory of mind such as deceptive
strategies and false-belief understanding (Polak & Harris, 1999; Russell et al., 1991), Level 2
perspective taking, and lying (Bigelow & Dugas, 2008) are related and develop in synchrony.
Accordingly, false-belief understanding is related to other abilities that involve representing
one and the same fact from different perspectives. Because this also holds true for gender
constancy, false-belief understanding might contribute to the understanding that a person’s
sex is constant despite perceptual changes. Gender constancy tasks entail questions on gender
consistency that make children focus on the reality (e.g., the child is really a boy) and test
whether they are misguided by the appearance (e.g., the child looks like a girl). Indeed, Trautner
et al. (2003) demonstrated that gender consistency and appearance–reality distinction coincide
independent of age. Because appearance–reality distinction and false-belief understanding share
aspects of theory of mind, false-belief understanding and gender constancy—in particular gender
consistency—might develop in tandem.
The Relation Between Gender Constancy and Time Comprehension
Certain theory-of-mind experiments require some time representation. This fact was not well
elaborated in theory–of-mind research, maybe because time comprehension has only recently
attracted greater attention of developmental psychologists (e.g., Suddendorf & Corballis,
DEVELOPMENT OF GENDER CONSTANCY 457
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2007). In an experiment by Gopnik and Astington (1988), children were shown a Smarties box
and were asked what they thought it contained. Of course, they said, ‘‘Smarties.’’ Next,
they were shown that, in fact, the box contained a pencil. Then they were asked what they
had believed was in the box. Before the onset of false-belief understanding, children said,
‘‘a pencil.’’ Only children with false-belief understanding were aware of the fact that they
previously erred. Besides false-belief understanding, this experiment has yet another component:
A past state must be compared to a present state. Thus, time representation is involved as well.
Time comprehension is even more explicitly involved in gender constancy tasks. These tasks
entail questions on gender stability that focus on the past and future sex of a protagonist.
Accordingly, children who are able to consider time as an important factor in the course of
events should also pass tests on gender stability.
It was assumed that time comprehension evolved in human phylogeny to allow a flexible
action control to secure future needs (‘‘Bischof-Ko¨ hler hypothesis,’’ Suddendorf & Corballis,
2007). For example, children around the age of 4 years old are able to plan ahead in numerous
different situations. They choose an appropriate tool to take into another room where a specific
tool is necessary to operate a toy (Suddendorf & Busby, 2005; Suddendorf, Nielsen, & von
Gehlen, 2011). They also decide correctly which suitable object (e.g., winter coat) to choose
when going to a cold and snowy place (Atance & Meltzoff, 2005; for further evidence of an
improvement between the ages of 3 and 5 in terms of future-oriented thinking, see Prencipe
& Zelazo, 2005).
There is also convergent evidence from different types of tasks on time comprehension that
4-year-olds understand various aspects of time. That is, they comprehend and produce temporal
terms (Busby Grant & Suddendorf, 2011; Harner, 1975), estimate short periods of time (Droit,
1994), and compare different durations of events (Halisch & Halisch, 1980; Levin, 1977). In
Bischof-Ko¨hler’s (2000) task on time comprehension, children represented durations of different
events by predicting which of three hourglasses (3, 4, and 5 min in duration) finished first and
last. This task tests whether children are able to acknowledge time as a potential factor that influ-
ences the outcome of an event. Children who scored highly when comparing the duration of
hourglasses also scored highly on another task that involved time understanding. A child could
search for a gift at one of two locations. An experimenter hid a gift at one of the two locations
while the child waited behind a curtain. If the curtain was closed for only a short period of time,
the experimenter must have hidden the gift at the near location. If the curtain was closed for
a longer period of time, the experimenter had most likely hidden the gift at the far location.
Children who compared the hourglasses correctly were more likely to succeed in this task as
well (Bischof-Ko¨hler, 2000). The correct comparison of hourglasses also related to a variation
of the delay gratification task. An hourglass indicated how long children had to wait until they
could open a wrapped gift. In the meantime, children had the possibility of playing with other
toys. Children who were competent in time comprehension played with the other toys in the
delay gratification task more frequently. While they were waiting, they occasionally checked
the remaining sand in the hourglass. In contrast, children with poor abilities in time compre-
hension were unable to draw their attention away from the present. This finding indicates that
correctly comparing hourglasses correlates with the ability to arrange the fulfillment of different
needs along the timeline (Bischof-Ko¨hler, 2000).
The questions on gender stability cover a more remote past and future than in the previously
reviewed studies on time comprehension. Despite this difference, gender stability and time
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comprehension might be related because once children comprehend that the past, the present,
and the future are organized on a timeline, the ‘‘mental time travel’’ (Suddendorf & Corballis,
2007) operates for any distance in time. Accordingly, time comprehension and gender stability
(as part of gender constancy) might develop in synchrony.
Beyond the specific relations between gender constancy, time comprehension, and theory of
mind, we suggest that these competencies might be part of a domain-general mechanism that
develops around the 4th birthday. That is, children become capable of reflecting on the frame
of reference. Frame-of-reference awareness could give rise to the specific abilities that are neces-
sary to solve the different tasks (see the Discussion for a detailed analysis).
Research Goals
Based on the elaborated critique on previous gender constancy tasks and on the review of the
contributions of false-belief understanding and time comprehension to gender constancy, this
study had two research goals:
1. Because previous reports on the development of gender constancy used tasks that
could be interpreted as fictional stories and were not very lifelike, we developed a
new gender constancy task that used real characters as models who dressed in clothes
of the opposite sex. We assessed the children’s developmental course of gender con-
stancy by asking questions concerning gender labeling, gender stability, and gender
consistency.
2. We tested different cognitive abilities that develop around the age of 4 years. Gender
consistency can be conceived of as an appearance–reality task, which is part of the
theory-of-mind development, and gender stability involves inferring past and future
characteristics of a protagonist. It should follow that false-belief understanding and
time comprehension correlate with gender constancy and the components of gender
consistency and gender stability. The present study was therefore designed to inves-
tigate the relationship between these abilities.
METHOD
Participants
The final sample consisted of 53 children (M
age
¼4;6, range ¼3;0–6;0; 25 girls), who were
subdivided into 3-year-olds (range ¼3;0–3;11, M
age
¼3;7; n¼16 [8 girls]), 4-year-olds (range ¼
4;0–4;11, M
age
¼4;6; n¼22 [11 girls]), and 5-year-olds (range ¼5;0–6;0, M
age
¼5;7; n¼15 [6
girls]). All children lived with both parents because we assumed that the terms ‘‘mommy’’ and
‘‘daddy,’’ which are used in the gender constancy task, would be more difficult for children who
lived with only one parent than for children who lived with two parents. Children were predo-
minantly from upper-middle-class Caucasian families. Two of the 53 children did not complete
the false-belief task but were retained in the final sample of the study. Twelve children were
additionally tested but not included in the study due to noncompliance (n¼6), living in
a single-parent family (n¼4), or procedural errors (n¼2). The children were recruited from
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several public day-care centers in a large German city, and their parents consented to their
participation in the study.
Material
For the gender constancy task, two videos were prepared—one presenting a 4-year-old boy and
the other a 4-year-old girl dressing in clothes typically worn by the opposite sex and playing
with toys typically played with by the opposite sex. In the first video, a boy wearing jeans
and a sweater played with a truck. Then, he took off the sweater, his T-shirt, and sneakers
but left on his white undershirt and underpants. Next, he put on a pink dress, white tights,
and sandals. Finally, he put on a wig and played with a doll. In the second video, a long-haired
girl wearing a white dress played with a doll. Next, she took off the dress and her sandals but left
on her white undershirt and underpants. Then, she put on a blue and orange T-shirt, jeans, and
sneakers. Finally, she hid her hair under a baseball cap. After she had finished dressing, she
played with a truck. Each film lasted for approximately 1 min.
In the time comprehension task, three hourglasses were used. Each hourglass consisted of
transparent glass with metal squares attached to the top and the bottom. The height of the
hourglasses was 31 cm, and it took 3, 4, and 5 min, respectively, for the sand to run through
the hourglasses.
In the false-belief task, a green metal box and a yellow metal box was used as was a single
ordinary key.
Procedure
Parents were contacted via telephone and scheduled for one appointment. Upon arrival, parents
and child were escorted to the test room. For approximately 10 min, the child and the exper-
imenter read a comic book or the child painted a picture, while a second experimenter started
an interview with the parent in another part of the room. When the child felt comfortable with
the new situation, time comprehension was tested, followed by false-belief understanding, and
finally gender constancy. Before the gender constancy task was administered, the children com-
pleted a series of other tasks that were not related to gender constancy and are not reported in the
present study. We decided to conduct the gender constancy task last because children became
distracted by the television once it had been turned on. The child was videotaped from an adjoin-
ing room, which was separated from the test room by a one-way mirror. The questions in the
following tasks are a literal translation of the original questions, which were asked in German.
Gender constancy task. Children were always presented with the video sequence showing
the same-sex peer first and the video sequence of the opposite-sex peer second. Before the
videos showing the dressing sequences were played, a freeze frame of the girl and boy wearing
sex-congruent clothes was presented. The child was asked the following questions.
Item 1: Is this child a girl or a boy? (gender labeling)
Item 2: When this child was a little baby, was the child a boy or a girl? (gender stability)
Item 3: When this child grows up, will the child be a mommy or a daddy? (gender stability)
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Next, the experimenter started the video demonstration. After the video had ended, the moni-
tor displayed a freeze frame of the child after the dressing sequence. Then, the experimenter
asked the following questions.
Item 4: Is this child a girl or a boy? (gender consistency)
Item 5: (if Item 4 was answered incorrectly): Is this child really a [boy=girl according to the actual
appearance of the depicted child]? (gender consistency)
When the child had answered all questions referring to the child in one video sequence, the
second video sequence was run.
We also calculated a score that represented the number of incorrect responses (10 – N
[incorrect responses]). For a better comparison across tasks, this score was transformed into
a percentage score.
Time comprehension task. The experimenter introduced one hourglass and demonstrated
the mechanism. The hourglasses were then presented in ascending order. Immediately after the
hourglasses had been inverted and started running, the participants were asked the following
pairs of questions (literal translation of the phrasing that turned out to be most appropriate
in colloquial German).
Item 1: Which hourglass will finish most quickly? Why?
Item 2: Which hourglass will take the longest? Why?
Thus, participants had to infer the duration from the amount of sand before having watched
the outcome of the process. After the hourglass with the smallest amount of sand had run
through, it was put aside, and the participants were prompted to compare the two remaining
hourglasses by answering the following items.
Item 3: Which hourglass will finish last?
Item 4: Which hourglass will finish first?
After all glasses had run through, they were presented again in the same positions, and the
questions of Pair II were asked in reverse order.
Item 5: Which hourglass finished first? Why?
Item 6: Which hourglass finished last? Why?
Finally, the positions of all three hourglasses were switched (with the longest-lasting one in
the center), and the children were questioned again using the two pairs of time concepts.
Item 7: Which hourglass finished most quickly?
Item 8: Which hourglass took the longest?
Item 9: Which hourglass finished first?
Item 10: Which hourglass finished last?
During this trial, the sand was not running through the hourglasses. Thus, while having pre-
viously experienced the sand running down, the children had to rely not solely on the position of
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the hourglass but on the height of the sand in the bottom part of the hourglass and remember the
corresponding running time.
We calculated a score that represented the number of incorrect responses (10 – n[incorrect
responses]). For a better comparison across tasks, this score was transformed into a percentage
score.
False-belief task. This task, previously used by Bischof-Ko¨hler (2000), was adapted from
the task used in Wimmer and Perner’s (1983) study: In Wimmer and Perner’s task, children were
told a story in which the protagonist, ‘‘Maxi,’’ puts a chocolate in a blue cupboard and goes
outside. While he is playing outside, his mother moves the chocolate from the blue cupboard
to a green cupboard. When children were asked where Maxi would look for his chocolate when
he came back, 3-year-olds incorrectly assumed that he would look in the green cupboard where
the mother put the chocolate. In contrast, 4-year-olds were aware that Maxi believed that the
chocolate would still be in the blue cupboard and would accordingly look for it there.
Bischof-Ko¨hler (2000) used a similar logic in her task, with the exception that children were
not told a story illustrated by schematic characters but rather witnessed the protagonist and
the change of location in real life. While the experimenter and the child were sitting at a table,
an assistant entered the room and asked the experimenter and the child to take care of her key.
The experimenter then placed a yellow tin and a green tin on the table, and the assistant
deposited her key into the yellow tin. When the assistant had left the room the experimenter
transferred the key to the green tin. Subsequently, the experimenter asked the child the following
questions.
Item 1: Where will [name of the assistant] look for her key when she returns?
Item 2: Does she know where her key is?
Item 3: Where does she believe her key is?
Additionally, to ascertain a correct recollection of the facts, the child was asked where the key
was now and where the other person had put it originally. In the case of wrong answers, the
experimenter corrected the child. Subsequently, the following questions were asked.
Item 4: Has [name of the assistant] seen that her key was put into this box? (The experimenter
points to the green box.)
Item 5: Where will she look for her key when she returns?
We calculated a score that represented the number of incorrect responses (5 – n[incorrect
responses]). For a better comparison across tasks, this score was transformed into a percentage
score.
RESULTS
Performance on the gender constancy task, the time comprehension task, and the false-belief task
did not differ as a function of the participants’ sex (all ps>.18). Therefore, both sexes were
combined for the following analysis. The data were analyzed by conducting regression analyses
and entering the independent variables stepwise with a threshold of p¼.05 (two-tailed). Table 1
presents the percentage score of the 3-, 4-, and 5-year-old children in each task.
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Gender Constancy Task
As detailed in Table 1, 4-year-olds and 5-year-olds significantly improved their performance in
gender constancy in comparison with the next younger age group. A closer look at the subtasks
revealed that 4-year-old children increased their performance significantly compared with
3-year-olds in all subtasks of the gender constancy task, whereas 5-year-olds only showed
further improvement in the gender consistency subtask.
To explore the two videos separately, we analyzed the answers for each subtask separately.
For the video displaying the boy, 100%of the questions on gender labeling were answered cor-
rectly (Item 1). The mean percentage of correct responses concerning the questions on gender
stability (Items 2 and 3) was 77%. The corresponding percentage for the gender consistency task
was 58%(i.e., 2 – [number of incorrect answers]). Forty-five percent of the children answered
correctly on Item 4. An additional 23%of the children answered correctly when they were asked
the same question containing the auxiliary ‘‘really’’ (Item 5).
For the video displaying the girl, 92%of the questions on gender labeling were answered
correctly (Item 1). The mean percentage of correct responses concerning the questions on gender
stability (Items 2 and 3) was 69%. The corresponding percentage for the gender consistency task
was 53%(i.e., 2 – [number of incorrect answers]). Forty percent responded correctly to Item 4, and
an additional 26%of the children answered correctly to Item 5, which contained the word ‘‘really.’’
The number of correct answers to the two videos did not differ significantly: for gender label-
ing, p¼.50, binomial test; for gender stability, t(52) ¼0.44, p¼.66; for gender consistency,
t(52) ¼1.1, p¼.28.
Time Comprehension Task
Table 1shows that 4-year-olds performed better than 3-year-olds in the time comprehension
task. In contrast, 4-year-olds and 5-year-olds did not show any difference in performance. Item
difficulty was medium to low. The percentage for each question ranged from 68%(Item 2) to
94%(Item 5).
TABLE 1
Means (and Standard Deviations in Parentheses) for the Tasks Gender Constancy
(Including Gender Labeling, Gender Stability, and Gender Consistency), Time
Comprehension, and False-Belief Understanding for 3-, 4-, and 5-Year-Olds
Age group
Task 3-Year-olds 4-Year-olds 5-Year-olds Mean F(2, 50) p
Gender Constancy 50%(21%)76%(22%)91%(17%)73%(26%) 16.23 <.001
Gender Labeling 88%(22%) 100%(0%)100%(0%)96%(13%) 5.82 <.01
Gender Stability 55%(36%)84%(25%)91%(15%)77%(30%) 8.65 <.01
Gender Consistency 27%(30%)57%(35%)85%(30%)56%(39%) 13.10 <.001
Time Comprehension 54%(31%)88%(19%)95%(10%)80%(27%) 16.32 <.001
False-Belief Understanding 56%(32%)76%(29%)93%(10%)75%(30%) 7.58 <.01
Significant increases in performance compared with the next younger age group (post-hoc tests, LSD).
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False-Belief Task
Table 1shows that 4-year-olds performed better than 3-year-olds in the false-belief task. In
contrast, 4-year-olds and 5-year-olds did not show any difference in performance. To assess
the item difficulty, we analyzed the percentage of correct answers for each question. Seventy-
three percent and 71%of the answers, respectively, were correct referring to the location where
the assistant will look for the key (i.e., Items 1 and 5, respectively). Forty-nine percent, 77%, and
90%of the answers, respectively, were correct concerning the questions on the mental states of
the assistant (i.e., Items 2, 3, and 4, respectively).
TABLE 2
Correlation Matrix Displaying the Relations Between Age, Gender Constancy, Gender Stability,
Gender Consistency, Time Comprehension, and False-Belief Understanding
Correlation matrix
Task Age
Gender
constancy
Gender
stability
Gender
consistency
Time
comprehension
False-belief
understanding
Age —.63 .53 .57 .63 .50
Gender Constancy —.89 .90 .57 .63
Gender Stability .83 —.63 .57 .53
Gender Consistency .84 .41 —.41 .55
Time Comprehension .31 .40 .10 —.76
False-Belief Understanding .46 .35 .37 .66 —
Note. The upper-right section represents zero-order correlations. The lower-left section represents partial correlations
after controlling for age.
TABLE 3
Regression Analyses to Determine the Predictors of Gender Constancy,
Gender Stability, and Gender Consistency
Variable BSEB bDR
2
Predicted variable: Gender constancy
First step .401
Age .005 .001 .633
Second step .128
False-Belief Understanding .716 .198 .414
Predicted variable: Gender consistency
First step .322
Age .003 .001 .567
Second step .092
False-Belief Understanding .366 .133 .351
Predicted variable: Gender stability
First step .327
Time Comprehension .255 .052 .571
p<.01. p<.001.
Note. Age, time comprehension, and false-belief understanding were entered stepwise in all analyses.
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Relation between tasks. One-way analyses of variance were conducted with the inde-
pendent variable of age (3-, 4-, and 5-year-olds), showing that the percentage score in each task
differed significantly, which suggests an increase in competence with age (see Table 1). Table 2
shows that the variables correlated significantly even after controlling for age.
To investigate the influence of time comprehension and false-belief understanding on gender
constancy, gender stability, and gender consistency, linear regression analyses were conducted.
Age, time comprehension, and false-belief understanding were entered stepwise in each
regression analysis using a forward selection method. This method adds the variable that
improves the regression function the most and repeats this process until none improve the
regression function. Table 3presents the variables that predicted gender constancy, gender
stability, and gender consistency. Age and false-belief understanding predicted gender constancy
as well as gender consistency, and time comprehension predicted gender stability.
DISCUSSION
We presented a new gender constancy task demonstrating that children as young as 4 years old
are able to pass this task when confronted with a lifelike presentation of peers dressing in
opposite-sex clothes and playing with opposite-sex toys. Furthermore, we showed that false-
belief understanding predicted gender constancy and in particular the subtask gender consist-
ency. We further demonstrated that time comprehension predicted the subtask gender stability.
Both relations were age-independent.
The present study is in line with previous work on gender constancy in which the authors
aimed to improve the salience of opposite-sex-dressing behavior. Slaby and Frey (1975) began
with a purely verbal measure. Emmerich et al. (1977) were the first to present schematic draw-
ings to illustrate the task. Finally, Bem (1989) used photographs for this task. Taking a step
further than Bem’s procedure of presenting photographs, we presented children with video
sequences of a girl and a boy putting on clothes and playing with toys typically associated with
the opposite sex. Similar to Bem, we found gender constancy with respect to other individuals
even in 4-year-olds. In contrast to Bem, we did not introduce the idea that wearing opposite-sex
clothes is a silly dressing-up game and did not present the protagonists’ genitals as a cue. It is
debatable whether these auxiliaries used by Bem might have helped children without gender
constancy to pass the task. However, we found further evidence for the notion that gender con-
stancy emerges around age 4 using a different procedure than that used by Bem.
In previous studies, reports on the onset of gender constancy varied between 3 and 7 years of
age. We consider the rather early onset of gender constancy in our study to be due to several
reasons. First, a lifelike presentation of children dressing and playing is less ambiguous than
schematic drawings (as in Emmerich et al., 1977), which have a high resemblance to comic stor-
ies in which physically impossible events seem possible. Accordingly, young children might
assume that changing gender is a possible transformation for fictional characters, too. Second,
one of the two questions on gender consistency included the term ‘‘really.’’ This auxiliary might
have helped children not to mistake the gender constancy task for a pretence game. We cannot
rule out the possibility that children simply said the opposite of what they had said before (i.e.,
‘‘no’’ for Item 5 where they were asked if this child is really a girl). However, this is not a very
likely explanation because, in general, young children tend to answer ‘‘yes’’ to yes–no questions
DEVELOPMENT OF GENDER CONSTANCY 465
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(Fritzley & Lee, 2003), and in particular, in our study, it was mainly children who performed
well in the time comprehension and false-belief tasks who rethought their first incorrect answer
in the gender constancy task. Taken together, these findings point to an earnest reasoning about
the experimenter’s question of whether the child in the video was really a boy or a girl.
We suggest that false-belief understanding and time comprehension directly contribute to the
performance in the gender constancy task. However, the correlation between tasks could be
interpreted in two alternative ways: either as an independent domain-specific but synchronic
development of these abilities that is caused by a general cognitive maturation, or as a causal
relationship between these abilities due to domain-general development (for a discussion of both
accounts, see Rakison & Yermolayeva, 2011). It has been suggested that cognitive abilities
develop rather independently in different modules: Baron-Cohen (1995) and Leslie (1987),
for example, put forward the idea that the development of mind reading proceeds on a relatively
innately specified pathway. It might be postulated that gender constancy, time comprehension,
and false-belief understanding also develop independently as distinct abilities that are based on
distinct mechanisms. A correlation between these abilities might be solely due to a synchronic
development that is caused by a general cognitive maturation.
These close relations between the variables could also be conceived of as the result of
advances of a domain-general mechanism. Which general cognitive mechanism could account
for advances in gender constancy, time comprehension, and false-belief understanding? We sug-
gest that a general cognitive mechanism labeled as frame-of-reference awareness could be the
reason for a synchronic development of the aforementioned abilities.
Frame-of-Reference Awareness
In the theoretical framework of Bischof-Ko¨ hler and Bischof (2007), false-belief understanding
and time comprehension are seen as the result of the general capacity to reflect upon frames
of reference. A frame of reference is a construct introduced by Gestalt theorists to account for
the essentially relative character of apparently absolute phenomena (Metzger, 1954). Although
mostly inconspicuous, its functioning can be reflected upon under certain conditions. The impact
of a frame of reference becomes prominent if it is in direct opposition to another frame of ref-
erence. For example, in a task on false-belief understanding including an unexpected transfer,
the children knew where the object was relocated, while the experimenter did not. The state
of knowledge of each protagonist represents the protagonist’s own frame of reference upon
which the protagonist acts. Reflecting on frames of reference means, in this example, that the
children comprehend that they know the actual position but that the experimenter does not.
To put it more generally, the kernel of this concept is that children understand that one and
the same fact can be represented differently depending on their individual perspective (for
similar accounts, see Iao, Leekam, Perner, & McConachie, 2011; Perner, Stummer, Sprung,
& Doherty, 2002).
Frame-of-reference awareness is conceptualized as a general mechanism that takes into
account an individual’s perspective when making inferences about mental states, but it also pro-
vides insight into other domains such as time. Conceiving of time as a frame of reference allows
the representation of past, present, and future events along a timeline and enables them to be
causally connected. Each point on this timeline is a frame of reference in its own right, which
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sheds a different light on one and the same fact. For example, if my present self is not hungry,
then an empty refrigerator is no problem for me. However, when imagining that my future self
will become hungry on a public holiday when the shops are closed, the empty refrigerator
reminds my present self to go to the supermarket even though I am not hungry at all. Accord-
ingly, frame-of-reference awareness might also lead to a mature understanding of a temporally
extended identity, in which individuals are conceived of as extending from the past and into the
future. It was hypothesized that children around the age of 4 develop a sophisticated understand-
ing of a ‘‘permanent identity’’ (Bischof, 2008) or a ‘‘proper self’’ (Povinelli, 2001). The kernel
of these concepts is that children are supposed to become capable of holding in mind the idea
that multiple representations of an individual (i.e., past, present, and future states) refer to the
same entity. As mentioned earlier, theorists have argued for a domain-general transition in
cognition at around 4 years of age and have suggested that time comprehension might
reflect this cognitive development (Bischof, 2008; Case, 1992; Perner, 1991; Perner, Mauer,
& Hildenbrand, 2011). Thus, frame-of-reference awareness might be an important ability to
understand that an individual’s sex is constant across time despite perceptual changes. Indeed,
Trautner et al. (2003) demonstrated that gender constancy and appearance–reality distinction
coincide independent of age. As mentioned, appearance–reality distinction can be considered
a result of reflecting upon frames of references. Hence, the results of Trautner and colleagues
might point to the contribution of frame-of-reference awareness to gender constancy.
There are at least two limitations of the present study. First, false-belief understanding and
time comprehension were correlated. Accordingly, this collinearity of the predictors might have
affected the results of the regression analysis by not estimating the predictive value of each pre-
dictor correctly. Second, to strengthen the idea of a domain-general development of different
cognitive abilities, future studies should test children’s general cognitive maturation more
directly. In this study, we controlled for chronological age and assumed that age is a proxy of
cognitive maturation (for similar procedures, see DiYanni, Nini, Rheel, & Livelli, 2012;
Trautner et al., 2003). Instead of considering age as an indicator of cognitive maturation, one
could apply a standardized IQ test. Additionally, specific cognitive abilities could have moder-
ated the correlations presented in this study. First, language abilities could have influenced the
relations between tasks. Despite the fact that children only had to point or give simple verbal
answers to indicate their response, the test questions required a certain level of receptive lan-
guage. Additionally, children had to inhibit the dominant response in the false-belief task and
in the gender constancy task (but not in the time comprehension task). Accordingly, receptive
language and inhibitory control should be additionally controlled for in future research. Beyond
controlling for inhibitory control as a potential moderator of the relation between tasks, future
studies should consider a permanent identity and time comprehension as beneficial for a child’s
inhibitory control when their own goals are involved. Once the child comprehends that a current
goal can be achieved not just in the present but also in the future, the child might gain a more
flexible action control. For example, the child might wait (as in the delay of gratification task,
Mischel, Shoda, & Peake, 1988) or perform subdominant actions (as in the windows task,
Russell et al., 1991) when the achievement of a current goal is anticipated in the future.
In sum, the present study showed that children around the age of 4 years develop the ability to
conceive of an individual’s sex as constant across time and perceptual changes. This study also
presented the hypothesis that gender constancy relates to time comprehension and false-belief
understanding, which develop around 4 years of age. The results provide compelling evidence
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that false-belief understanding predicts gender constancy and gender consistency and that time
comprehension predicts gender stability even after controlling for age. This relation might be
reflected in the ability to assign a permanent identity to the self and to other individuals, which
is independent of appearance. Contrary to the present emphasis on the domain-specific
modularity of cognitive capabilities, the remarkable correspondence of these features points to
a fundamental reorganization of children’s representational abilities at around 4 years of age,
and it might be fruitful to reconsider the existence of domain-general mechanisms such as
frame-of-reference awareness.
REFERENCES
Atance, C. M., & Meltzoff, A. N. (2005). My future self: Young children’s ability to anticipate and explain future states.
Cognitive Development,20, 341–361. doi:10.1016=j.cogdev.2005.05.001
Avis, J., & Harris, P. L. (1991). Belief–desire reasoning among Baka children: Evidence for a universal conception of
mind. Child Development,62, 460–467.
Baillargeon, R., Scott, R. M., & He, Z. (2010). False-belief understanding in infants. Trends in Cognitive Sciences,14,
110–118. doi:10.1016=j.tics.2009.12.006
Baron-Cohen, S. (1995). Mindblindness. Cambridge, MA: MIT Press.
Bem, S. L. (1989). Genital knowledge and gender constancy in preschool children. Child Development,60,
649–662.
Bigelow, A. E., & Dugas, K. (2008). Relations among preschool children’s understanding of visual perspective taking,
false belief, and lying. Journal of Cognition and Development,9, 411–433.
Bischof, N. (2008). Psychologie [Psychology]. Stuttgart, Germany: Kohlhammer.
Bischof-Ko¨ hler, D. (2000). Kinder auf Zeitreise [Children’s mental time travel]. Bern, Germany: Hans Huber.
Bischof-Ko¨ hler, D. (2012). Empathy and self-recognition in phylogenetic and ontogenetic perspective. Emotion Review,
4, 40–48. doi:10.1177=1754073911421377
Bischof-Ko¨ hler, D., & Bischof, N. (2007). Is mental time travel a frame-of-reference issue? (Comment=reply).
Behavioral and Brain Sciences,30, 316–317. doi:10.1017=S0140525X07002014
Busby Grant, J., & Suddendorf, T. (2011). Production of temporal terms by 3-, 4-, and 5-year-old children. Early
Childhood Research Quarterly,26, 87–95. doi:10.1016=j.ecresq.2010.05.002
Buttelmann, D., Carpenter, M., & Tomasello, M. (2009). Eighteen-month-old infants show false belief understanding in
an active helping paradigm. Cognition,112, 337–342. doi:10.1016=j.cognition.2009.05.006
Case, R. (1992). The mind’s staircase: Exploring the conceptual underpinnings of children’s thought and knowledge.
Hillsdale, NJ: Lawrence Erlbaum.
Clark, E. V. (1997). Conceptual perspective and lexical choice in acquisition. Cognition,64, 1–37. doi:10.1016=
S0010-0277(97)00010-3
de Lisi, R., & Gallagher, A. M. (1991). Understanding of gender stability and constancy in Argentinean children.
Merrill-Palmer Quarterly: Journal of Developmental Psychology,37, 483–502.
DiYanni, C., Nini, D., Rheel, W., & Livelli, A. (2012). ‘I won’t trust you if I think you’re trying to deceive me’:
Relations between selective trust, theory of mind, and imitation in early childhood. Journal of Cognition and
Development,13, 354–371. doi:10.1080=15248372.2011.590462
Droit, S. (1994). Temporal regulation of behavior with an external clock in 3-yr-old children: Differences between
waiting and response duration tasks. Journal of Experimental Child Psychology,58, 332–345. doi:10.1006=
jecp.1994.1038
Eaton, W. O., & von Bargen, D. (1981). Asynchronous development of gender understanding in preschool children.
Child Development,52, 1020–1027. doi:10.2307=1129107
Emmerich, W., Goldman, K. S., Kirsh, B., & Sharabany, R. (1977). Evidence for a transitional phase in the development
of gender constancy. Child Development,48, 930–936. doi:10.2307=1128343
Flavell, J. H. (1988). The development of children’s knowledge about the mind: From cognitive connections to mental
representations. In J. W. Astington, P. L. Harris & D. R. Olson (Eds.), Developing theories of mind (pp. 244–267).
Cambridge, UK: Cambridge University Press.
468 ZMYJ AND BISCHOF-KO
¨HLER
Downloaded by [Universitaetsbibliothek Dortmund] at 07:19 24 August 2015
Flavell, J. H. (2004). Theory-of-mind development: Retrospect and prospect. Merrill-Palmer Quarterly,50, 274–290.
Flavell, J. H., Everett, B. A., Croft, K., & Flavell, E. R. (1981). Young children’s knowledge about visual perception:
Further evidence for the Level 1–Level 2 distinction. Developmental Psychology,17, 99–103. doi:10.1037=
0012-1649.17.1.99
Flavell, J. H., Flavell, E. R., & Green, F. L. (1983). Development of the appearance–reality distinction. Cognitive
Psychology,15, 95–120. doi:10.1016=0010-0285(83)90005-1
Fritzley, V., & Lee, K. (2003). Do young children always say yes to yes–no questions? A metadevelopmental study of the
affirmation bias. Child Development,74, 1297–1313. doi:10.1111=1467-8624.00608
Gopnik, A., & Astington, J. W. (1988). Children’s understanding of representational change and its relation to the under-
standing of false belief and the appearance–reality distinction. Child Development,59, 26–37. doi:10.2307=1130386
Halisch, C., & Halisch, F. (1980). Cognitive assumptions of young children’s self-evaluation reactions after success and
failure. Zeitschrift fu¨ r Entwicklungspsychologie und Pa¨dagogische Psychologie,12, 193–212.
Harner, L. (1975). Yesterday and tomorrow: Development of early understanding of the terms. Developmental
Psychology,11, 864–865. doi:10.1037=0012-1649.11.6.864
Iao, L.-S., Leekam, S., Perner, J., & McConachie, H. (2011). Further evidence for nonspecificity of theory of mind in
preschoolers: Training and transferability in the understanding of false beliefs and false signs. Journal of Cognition
and Development,12, 56–79. doi:10.1080=15248372.2011.539523
Kohlberg, L. S. (1966). A cognitive-developmental analysis of children’s sex-role concepts and attitudes. Stanford, CA:
Stanford University Press.
Leslie, A. M. (1987). Pretense and representation: The origins of ‘theory of mind.’ Psychological Review,94, 412–426.
doi:10.1037=0033-295X.94.4.412
Levin, I. (1977). The development of time concepts in young children: Reasoning about duration. Child Development,
48, 435–444. doi:10.2307=1128636
Lloyd, B., & Stroyan, J. (1994). Preschool children’s genital knowledge: Does Bem’s report of a male deficit survive
replication? British Journal of Developmental Psychology,12, 251–258.
Marcus, D. E., & Overton, W. F. (1978). The development of cognitive gender constancy and sex role preferences. Child
Development,49, 434–444. doi:10.2307=1128708
Martin, C. L., & Halverson, C. F. (1983). Gender constancy: A methodological and theoretical analysis. Sex Roles,
9, 775–790. doi:10.1007=BF00290030
Metzger, W. (1954). Psychologie [Psychology]. Darmstadt, Germany: Steinkopff.
Mischel, W., Shoda, Y., & Peake, P. K. (1988). The nature of adolescent competencies predicted by preschool delay of
gratification. Journal of Personality and Social Psychology,54, 687–696. doi:10.1037=0022-3514.54.4.687
Moll, H., & Meltzoff, A. N. (2011). How does it look? Level 2 perspective-taking at 36 months of age. Child
Development,82, 661–673. doi:10.1111=j.1467-8624.2010.01571.x
Nelson, P. B., Adamson, L. B., & Bakeman, R. (2012). The developmental progression of understanding of mind during
a hiding game. Social Development,21, 313–330. doi:10.1111=j.1467-9507.2011.00638.x
Perner, J. (1991). Understanding the representational mind. Cambridge, MA: MIT Press.
Perner, J. (2010). Who took the cog out of cognitive science? Mentalism in an era of anti-cognitivism. In P. A. Frensch &
R. Schwarzer (Eds.), Cognition and neuropsychology: International perspectives on psychological science (Vol. 1,
pp. 241–261). Hove, UK: Psychology Press.
Perner, J., Mauer, M. C., & Hildenbrand, M. (2011). Identity: Key to children’s understanding of belief. Science,333,
474–477. doi:10.1126=science.1201216
Perner, J., Stummer, S., Sprung, M., & Doherty, M. (2002). Theory of mind finds its Piagetian perspective: Why
alternative naming comes with understanding belief. Cognitive Development,17, 1451–1472. doi:10.1016=S0885-
2014(02)00127-2
Piaget, J. (1954). The construction of reality in the child. New York, NY: Basic Books.
Polak, A., & Harris, P. L. (1999). Deception by young children following noncompliance. Developmental Psychology,
35, 561–568. doi:10.1037=0012-1649.35.2.561
Povinelli, D. J. (2001). The self: Elevated in consciousness and extended in time. In C. Moore & K. Lemmon (Eds.), The
self in time (pp. 75–95). Mahwah, NJ: Lawrence Erlbaum.
Prencipe, A., & Zelazo, P. D. (2005). Development of affective decision making for self and other: Evidence for the
integration of first- and third-person perspectives. Psychological Science,16, 501–505. doi:10.1111=j.0956-
7976.2005.01564.x
DEVELOPMENT OF GENDER CONSTANCY 469
Downloaded by [Universitaetsbibliothek Dortmund] at 07:19 24 August 2015
Rakison, D. H., & Yermolayeva, Y. (2011). How to identify a domain-general learning mechanism when you see one.
Journal of Cognition and Development,12, 134–153. doi:10.1080=15248372.2010.535228
Russell, J., Mauthner, N., Sharpe, S., & Tidswell, T. (1991). The ‘windows task’ as a measure of strategic deception
in preschoolers and autistic subjects. British Journal of Developmental Psychology,9, 331–349.
Slaby, R. G., & Frey, K. S. (1975). Development of gender constancy and selective attention to same-sex models.
Child Development,46, 849–856. doi:10.2307=1128389
Sodian, B. (1991). The development of deception in young children. British Journal of Developmental Psychology,
9, 173–188.
Sodian, B. (2011). Theory of mind in infancy. Child Development Perspectives,5, 39–43.
Suddendorf, T., & Busby, J. (2005). Making decisions with the future in mind: Developmental and comparative
identification of mental time travel. Learning and Motivation,36, 110–125. doi:10.1016=j.lmot.2005.02.010
Suddendorf, T., & Corballis, M. C. (2007). The evolution of foresight: What is mental time travel, and is it unique to
humans? Behavioral and Brain Sciences,30, 299–313.
Suddendorf, T., Nielsen, M., & von Gehlen, R. (2011). Children’s capacity to remember a novel problem and to secure its
future solution. Developmental Science,14, 26–33. doi:10.1111=j.1467-7687.2010.00950.x
Szkrybalo, J., & Ruble, D. N. (1999). ‘God made me a girl’: Sex-category constancy judgments and explanations
revisited. Developmental Psychology,35, 392–402. doi:10.1037=0012-1649.35.2.392
Trautner, H. M., Gervai, J., & Nemeth, R. (2003). Appearance–reality distinction and development of gender constancy
understanding in children. International Journal of Behavioral Development,27, 275–283. doi:10.1080=
01650250244000362
Wehren, A., & de Lisi, R. (1983). The development of gender understanding: Judgments and explanations. Child
Development,54, 1568–1578. doi:10.2307=1129820
Wellman, H. M., Cross, D., & Watson, J. (2001). Meta-analysis of theory-of-mind development: The truth about false
belief. Child Development,72, 655–684. doi:10.1111=1467-8624.00304
Wimmer, H., & Perner, J. (1983). Beliefs about beliefs: Representation and constraining function of wrong beliefs in
young children’s understanding of deception. Cognition,13, 103–128. doi:10.1016=0010-0277(83)90004-5
470 ZMYJ AND BISCHOF-KO
¨HLER
Downloaded by [Universitaetsbibliothek Dortmund] at 07:19 24 August 2015
