GSTF International Journal of Law and Social Sciences (JLSS) Vol.1 No.2, July 2012
“Fourth Grade Slump in Creativity”:
Development of Creativity in Primary
School Children
Zohreh Darvishi#1, Shahla Pakdaman#2
#1
Department of Cognitive Sciences, Institute for Cognitive Science Studies,
#1
Department of Psychology, Shahid Beheshti University
#2
Department of Psychology, Shahid Beheshti University
Tehran-Iran
1
[email protected]
2
[email protected]
studies on the subject and have given many
definitions for creativity over the last decades.
However, there has not been a fixed single one,
there is one exclusive and common, in which most
agree, i.e., creativity is the process of creating
something novel, valuable, useful and generative"
in [1-3] ". Regarding cognition, creativity has two
important components, divergent thinking and
problem solving which increase the person’s
ability to adapt with the environment and the
surrounding events "for example, see[4]".Divergent
thinking is anecessary and measurable factor in
creativity which occurs because of different and
separate cognitive actions in brain " in [5,6] " and
means that it enables the ability to create different
and various ideas for solving a single problem
(Runco, 1990, " as cited in [7] " ). Based on
Guilford model " in [8] ", divergent thinking is
divided into different cognitive components like
fluency, i.e.,the ability to create several ideas and
solutions, flexibility, i.e., the capability of an
individual to transfer from one group or category to
another, originality, i.e., the ability to create new,
unique and unusual ideas for solving a problem
which is different from the ordinary and routine
ones and elaboration which means the ability to
include the details and the meanings to the answers
and creative ideas.
Problem solving is considered creative (CPS),
when the person is faced with ill-defined, illstructured or heuristic problems. Complexity of
these cases is in a way that cannot be solved with
just using convergent thinking. Several CPS models
have been introduced and developed " for example,
see[9,10]".
Abstract- The aims of this study included the
investigation of the developmental trend of creativity
and its components (originality, fluency, flexibility
and elaboration) in primary school children in the city
of Tehran as well as the possibility of " Fourth grade
slump in creativity". 400 children ( 200 males and 200
females ) were randomly selected by cluster sampling
from 30 elementary schools of one educational region
in Tehran. Data were gathered using TTCT-figural,
form A and were analysed using two-way ANOVA,
Trend analysis, repeated measure ANOVA and
planned tests. Findings and results showed that
developmental trend of creativity is a function of
third degree. Creativity scores increase from grade
one to grade three, then decrease with a sharp slope
between the third and fourth grade and increase
again in fifth grade. There was no significant
difference in development of creativity between two
genders. however, a significant difference was found
between boys and girls. The main component of
developmental changes in creativity in both girls and
boys, was elaboration. It seems that creativity in
primary school children follows a developmental
course and the variations of scores specific to
elaboration.
Keywords- creativity slump, developmental trend,
elaboration, flexibility, fluency, originality
I. INTRODUCTION
Researchers on creativity domain, especially
psychologists, have done numerous and extensive
DOI: 10.5176/2251-2853_1.2.34
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© 2012 GSTF
GSTF International Journal of Law and Social Sciences (JLSS) Vol.1 No.2, July 2012
One of the issues that creativity researchers pay
attention to is developmental trend of creativity.
The researchers, who reported discontinuity in
creativity development, have shown that as time
passes some growth and drop periods happen in
creativity development "in[11-14]".Torrance (1968)
following a longitudinal study, realized that the
highest creativity drop in elementary school
children happens at around the age of 9 and after
passing a period of stagnation and as reaching to
teenage period, the decline is decreased gradually.
This phenomenon is called “Fourth grade slump in
creativity”. Other studies also mentioned the
creativity decrease in this period " for example, see
[15,16]".
Divergent thinking components, as main and
central core in creativity, have developmental trend
including one or more drops. The number of studies
showing the developmental trend of each
component of creativity in children and teenagers
separately is limited. But those few existing
numbers show that the general creativity decline,
correlates with decline in one or some of the
divergent thinking components. Also the rate of
decline in these components, according to gender,
has been reported differently " for example, see
[17] " .
The issue of “ Fourth grade slump in creativity”
which was first introduced by Torrance has been
inspirational for many future researches in studying
the developmental trend of creativity and some
patterns and existing factors in the developmental
trend of divergent thinking in different educational
levels. Later, Torrance himself showed that these
kinds of slumps in case of existence are curable and
since they can occur because of the shortcomings
and defects of educational system, with proper
changing in this system they can be curable " in
[18] ".
Study of creativity development and recognition
of possible slumps is considered important for
psychologists because in addition to recognition of
complex and multi-dimensional nature of creativity,
a remarkable evaluation of educational barriers in
classrooms and courses happens. The decrease in
creativity can happen as a child’s response against
environment, including educational environment, or
personal experience. Therefore, the environments
recognition and the child’s type of experience and
the effort for the proper change of it can be
effective in omitting the possible creativity slump "
for example see [19] ". According to this, the main
purpose of this study is to investigate the
developmental trend of creativity and its
components in primary school children in the city
of Tehran as well as the possibility of existence the
fourth grade slump in creativity.
II. METHOD
A. Participants
400 children (200 males and 200 females) were
randomly selected by cluster sampling from 30
public elementary schools of Tehran, educational
district 3. They were studying in all five grades in
the academic year of 2010-2011.
B. Apparatus and Procedure
There are two types of Torrance Test for Creative
Thinking (TTCT), figural and verbal, including two
parallel forms of A and B, which are of the most
efficient and important standardized tools for
measuring creativity introduced by Torrance(1966)
and has been renormalized in 1974, 1984, 1990 and
1998 respectively " in [20] ". The TTCT figural,
form A (Torrance, 1974) has been used in this
research " in [21] ". This pen and paper-based test
evaluates four main cognitive components of
creativity: a) originality b) fluency c) flexibility
and d) elaboration and it contains 3 ten-minute
assignments: making picture, completing picture,
incorporating parallel lines in order to draw
picture. Each assignment will be scored for
originality andelaboration, but the two assignments
(completing picture and incorporating parallel lines
in order to draw picture) will be scored for fluency
and flexibility as well.
As stated in TTCT manuals of 1966 and 1974, the
test–retest reliability coefficients have ranged from
0.50 to 0.93. Interpreter reliability for the TTCTfigural Manual of 1990 among the scorers was
greater than 0.90. As reported by TTCT-figural
Manual of 1998, the reliability estimates of the
creative index from Kuder–Richardson 21 using
99th percentile scores as the estimates of the
number of items ranged between 0.89 and 0.94"as
cited in [20] ".
Khaefi (1993, "as cited in [22] ") measured the
reliability of the Iranian version of the TTCTfigural form A and form B. He reported the testretest reliability of TTCT-figural form B
components as: fluency (0.78), elaboration (0.91),
flexibility (0.81), originality (0.74) and overall test
score (0.80). In this research, selected students in
each grade were tested individually as well as in
group. TTCT-figural form A was done in about 3035 minutes in each class.
III.FINDINGS AND RESULTS
Descriptive results for all grades' scores on the
TTCT, according to gender are shown in Table 1.
The highest mean cretivity score in both females
(M=181.1, SD=32.45) and males (M=162.5,
SD=32.95) are of the third grade. Ignoring the
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GSTF International Journal of Law and Social Sciences (JLSS) Vol.1 No.2, July 2012
gender variable, the highest mean in overall
creativity score can be seen in the third grade
)M=172.1, SD=33.91) . Considering the data, it can
be observed that the developmental trend of
creativity in both genders, first had a rising trend
and it increases to the third grade. It sees a decline
in fourth grade and then in fifth grade starts
increasing again. Table 2 shows the results of the
two-way ANOVA for creativity scores accroding to
gender and grade. Since the interaction between
gender and grade had no significant effect
(p=0/265>0/05) in creativity scores, developmental
trend of creativity is examined only according to
grade. Accroding to table 3, first, second and fourth
degree models are not fit with the data and
developmental trend of creativity is a function of
third degree. Diagram 1 shows data fitting with
third degree model accroding to gender and grade.
Accroding to tables 2 and 3 as well as diagram 1,
creativity in fourth grade, both in females and
males, faces a sharp slump and it increases in fifth
grade. Based on the information in table 4, the
interaction between gender and third and fourth
grade has no significant effect (p=0/714>0/05) in
the amount of creativity slump. Since the tables and
diagram show a decrease of total score of creativity
in fourth grade, the obtained results of a more
accurate study of the the process of developmental
trend of creativity factors is reported. Table 5 shows
results of two-way ANOVA for the fluency
accroding to gender and grade and illustrates the
fact that the interaction between gender and grade is
significant (p=0/006<0/05). Table 6 shows that
there is a significant difference between two
genders on the developmental trend of fluency
component. Results from the two-way ANOVA for
the flexibility component accroding to gender and
grade show that interaction of gender and grade is
significant in thedevelopmental trend of flexibility
component (p=0/01< 0/05). Therefore, ANOVA
and Trend analysis are also calculated for both
genders. The results of ANOVA according to
gender separation is shown in table 7. Table 8
shows the results of two-way ANOVA for the
originality component according to gender and
grade. Based on table 8, the interaction between
gender and grade does not make a significant
difference (p=0/097>0/05) in developmental trend
of originality component. As a result, two-way
ANOVA was done without considering gender,
only according to grade and showed the
developmental trend of originality component has a
function of third degree (p=0/827>0/05 ). It means
that the higher grade goes, the more originality
component increases, but it changes direction in the
course of transition. Table 9 shows the results of
two-way ANOVA for the elaboration component
according to gender and grade. It shows that
interaction between gender and grade does not
make a significant difference (p=0/325>0/05). As a
result, two-way ANOVA was done without
considering gender and only accroding to the grades
and the outcome showed that if (α =0/05) is
considered, none of the models have fitting, but
if (α=0/01) is considered the third degree model has
fitting (p=0/029>0/01). To examine the difference
between the developmental trend of different
creativity components ANOVA with repeated
measures was used. According to table 10,
interaction between creativity components and
grade is significant (p>0/001> 0/05) which means
that the developmental ternd of creativity
components are different. Based on table 10 and
diagram 2, the main factor for major creativity
transitional changes in every gender of elementary
school children is elaboration component.
Iv.CONCLUSIONS
The obtained results from the current study show
that the development of creativity in elementary
school children has an uneven trend. Children’s
creativity has an upward trend until third grade of
elementary school and then reaching fourth grade it
faces a slump and in fourth grade we observe the
highest rate of creativity slump in both females and
males. Then reaching fifth grade creativity
increases in both genders.
Students’ experiences are not merely gained at
school and cognitive, social and cultural factors can
be influential on students’ creativity.As researchers
beleives " for example see [23] " some of these
factors include cognitive factors (e.g., thinking,
attention and memory), motivational factors (e.g.,
encouragement of students’ innovation and
curiosity), social factors (e.g., the freedom of
speech ability, compatibility with others, avoid
destructive criticism and pay attention to children
without comparing them to other peers), and
personality factors (lack of adherence and
compatibility with others, being risk-taking and the
ability to be open to new experiences).
Specifically, creativity researchers have shown that
in order to present a creative work, presence of
some personality traits such as independence,
confidence, ability to self expression, stating
creative ideas and not following others are essential
" for example see [24, 25] ". Therefore, it seems
that to know and explain the developmental trend of
creativity in primary school children and the
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GSTF International Journal of Law and Social Sciences (JLSS) Vol.1 No.2, July 2012
creativity slump in fourth grade better, it is
necessary to consider all the above-mentioned
factors.
As a result, researchers explain the fourth grade
slump according to educational and social system
when students enter school they experience it.
Torrance (1970, " as cited in [18]" ) believes that
having a more organized and more official
educational system in the middle years of
elementary school causes less attention to
imagination and creativity of the child which has a
fundamental role in creative thinking. Torrance also
believes that being put in a peer competitive
atmosphere makes students’ interest towards
providing creative abilities decrease. To Gardner’s
point of view (1982," as cited in [25] ") the realistic
increase of children following their entrance to
higher educational levels and for their more
awareness of social rules happens, their mental
representations to the world change and head
towards objectivity. This matter can cause a decline
in their creativity. It limits the opportunities to
create and set the effective educational methods on
creativity. The most popular and useful theory is
discontinuity in creativity theory that has been
presented by Runco (1999-2007, " as cited in [26]
") . This theory has compatibility with Kohlberg
stage theory. According to this, with children’s
entrance from preconventionl stage to conventional
stage and the pressure from conformity with social
norms and following other’s opinions, uncustomary
ideas and thoughts, not only will not be encouraged,
but will also be clearly prevented and stopped. This
is when presenting uncustomary and unusual ideas
is vital for creative thinking. Yet, Runco " in [27] "
emphasizes on children’s brain transition at this
time. He believes at 9 or 10 the nervous system
reaches a point in growth and maturity which
causes children to be sensitive about conventional
rules and individual abilities and it made them enter
the conventional stage and caused the occurrence of
a slump in their creativity in fourth grade.
Another important finding in this study is that
there was no significant difference in development
of creativity between two genders. Since the
general slump of creativity in both genders was
accompanied by a decrease in almost all of the
creativity components, it seems that the same
educational system governing both male and female
elementary school children is the main reason for
this result. Also, the elaboration factor in this study
is the main factor for developmental changes in
both males and females. According to the creativity
researchers based on creativity stage models and
physiologic models of creativity " for example see
[28] " and also according to the accepted meaning
of creativity, in which the creative product must be
useful and beneficial, the creative person should be
able to present the final creative idea. For this
reason, the elaboration stage may be the most
important stage in production of creative product .
Without passing this stage the creative idea cannot
be credited. Therefore the rate of usefulness and
practicality will not be considered and it is possible
that despite creating unique and valuable idea, the
social and cultural value of it is lost and never be
recognized. Thus; it is essential and necessary for
the educational system, families and founders of
propagating creative culture especially in the area
of the fourth grade creativity decline to pay
attention to the recognition and training of the
elaboration component in children.
ACKNOWLEDGMENT
Z. Darvishi and Sh. Pakdaman would like to thank
all teachers and students of educational district 3 in
Tehran who participated in this research.
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GSTF International Journal of Law and Social Sciences (JLSS) Vol.1 No.2, July 2012
Table 1. means and standard deviation of TTCT scores according to gender and grade
gender
grade
M
S.D
first
109.8
36.56
second
132.6
44.77
third
181.8
32.45
fourth
164.8
25.95
fifth
179.9
42.86
total
153.8
46.38
first
104.1
38.86
second
133.5
38.37
third
162.5
32.95
fourth
149.4
39.10
fifth
157.7
42.02
total
141.4
43.48
first
106.9
37.60
second
133.1
41.43
third
172.1
33.91
fourth
157.1
33.881
fifth
168.8
43.62
total
147.6
45.32
female
male
total
Table 2. Two-way ANOVA in creativity according to gender and grade
source
df
SS
gender
1
15202/8
202/8
10/65
.001
grade
4
240409/7
60102/4
42/11
.000
interaction between gender and grade
4
7490/9
1872/73
1/31
.265
error
390 556552/6
total
399
MS
F
Sig
1427/05
819656/1
Table 3. summary of the Trend analysis of developmental trend of creativity
Model
observed contrast the expected amount based on null hypothesis difference between the observed amountand expected amount S.D
first degree
46/710
Sig
0
46/71
4/22
>.001
second degree -22/180
0
-22/18
4/22
>.001
third degree
4/34 0
0
4/34
4/22
.030
fourth degree
17/660
0
17/66
4/22
>.001
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GSTF International Journal of Law and Social Sciences (JLSS) Vol.1 No.2, July 2012
gender
Male
The mean of creativity scores
Female
grade
Diagram 1. data fitting with third degree model according to gender and grade
Table 4. summary of two-way ANOVA for creativty according to gender and third and fourthgrades
source
df
SS
MS
F
Sig
gender
1
12058/25
12058/25 11/107
.001
grade
1
9015/00
9015/00
8/304
.005
interaction between gender and grade 1
146/30
146/30
0/135
0/714
error
156
169364/52
1085/67
total
159
190584/09
Table 5.summary of two-way ANOVA for the fluency component accroding to gender and grade
source
df
SS
gender
1
23/04
grade
4
interaction between gender and grade
4
error
390
total
399
MS
F
Sig
23/04
0/895
0/345
3090/24
772/56
30/00
>0/001
378/71
94/67
10043/2
25/75
3/677
0/006
13535/19
Table 6. summary of analysis of one-way variance for the fluency component based on gender and grade separation
gender
male
female
source
df
grade
4
error
195
total
199
grade
SS
MS
F
1331.280
332.820
12.314
4
2137.670
534.418
21.835
error
195
4772.725
24.476
total
199
Sig
>0/001
> 0/001
6910.395
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GSTF International Journal of Law and Social Sciences (JLSS) Vol.1 No.2, July 2012
Table 7. summary of one-way ANOVA for the flexibility component according to grade and gender separation
gender
male
female
source
df
SS
MS
F
7.815
> 0/001
19.248
> 0/001
grade
4
590.630
147.658
error
195
3684.325
18.894
total
199
4274.955
grade
4
1285.470
321.368
error
195
3255.725
16.696
total
199
4541.195
Sig
Table 8. summary of two-way ANOVA for the originality component according to gender and grade
source
df
SS
gender
1
588/06
grade
4
12795/86
interaction between gender and grade
MS
4
874/32
error
390
43020/12
total
399
57278/37
F
Sig
588/06
5/33
0/021
3198/96
29
218/58
> 0/001
1/98
0/097
110/30
Table 9. summary of two-way ANOVA for the elaboration component according to gender and grade
source
df
SS
MS
F
gender
1
9034/50
9034/50
17/86
grade
4
82688/21
interaction between gender and grade
4
2357/83
589/45
error
390
197203/92
505/65
total
399
20672/05 40/88
1/16
Sig
> 0/001
> 0/001
0/325
Table 10. summary of ANOVA with repeated measures according to developmental trend of components and grade
source
df
SS
MS
type of component
1/23
798318/205
interaction between the component and grade
4/95
40109/526
8100/345
488/96
125891/269
257/463
error
644899/448
F
Sig
2504/826
> 0/001
31/462
> 0/001
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GSTF International Journal of Law and Social Sciences (JLSS) Vol.1 No.2, July 2012
elaboration
originality
fluency
flexibility
grade
Diagram 2.developmental trend of creativity components according to grade
[11] E. P. Torrance,A longitudinal examination of the fourth
grade slump in creativity. Gifted Child Quarterly, 12, pp.
195–199, 1968.
REFERENCES
[1] P. D. Stokes,“ Novelty,” in Encyclopedia of creativity, M.
A. Runco and S. R. Pritzker,Eds.San Diego, CA: Academic
Press, 1999, pp. 297-304.
[12] G. Smith and I. Carlsson,“Creativity in middle and late
school years,”International Journal of Behavioral
Development, 8, pp. 329–343, 1985.
[2] M. D. Mumford, “ Where have we been, where are
wegoing? Taking stock in creativity research, ”Creativity
Research Journal, 15, pp. 107–120, 2003.
[13] R. S. Albert,“Some reasons why childhood creativity often
fails to makeit past puberty into the real world ,”in
Creativity from Childhood through Adulthood:
TheDevelopmental Issues,M. A. Runco, Ed. San
Francisco, CA: Jossey-Bass Publishers, pp.43-56,1996.
[3] J. Plucker, R. Beghetto and G. Dow, “ Why isn’t creativity
more important to educational psychologists? Potentials,
pitfalls, and future directions in creativity research,”
Educational psychologist, 39 (2), pp. 83-96, 2004.
[14] R. E. Charles and M. A. Runco, “ Developmental trends
in the evaluation and divergent thinking of children,
”Creativity research journal, 13, pp. 417-437, 2001.
[4] T. M. Amabile and B. A. Hennessey, “ Creativity ,” (2011,
Jun).Creativity.The Annual Review of Psychology,pp.574577,Available:http://llk.media.mit.edu/courses/readings/He
nnesseyCrRev.pdf
[15] S. Amiri and S. Assadi, “ Development of creativity in
children, ”Advances in Cognitive Science, 9(4), pp. 2632, 2006.
[5] D. Moore, R. Bhadelia, R Billings, C. Fulwiler, K.
Heilman, M. J. Rood and D. Gansler, “ Hemispheric
connectivity and the visual-spatial divergent thinking
component of creativity,”Brain and Cognition, 70, pp.
267–272, 2009.
[16]
T. I. Lubart and A. Georgsdottir, “Creativity:
Development and cross-cultural issues, ” Creativity:
When East meets West, S. Lau, ANN. Hui, and GYC
Ng,Eds.Singapore World Scientific Publishing, pp. 2354, 2004.
[6] P. J. Silvia, B. P. Winterstein, J. T. Willse, C. M. Barona, J.
T. Cram, K. I. Hess, J. L. Martinez and C. A. Richard, “
Assessing creativity with divergent thinking tasks:
Exploring the reliability and validity of new subjective
scoring methods,”Psychology of Aesthetics, Creativity, and
the Arts, 2, pp. 68–85, 2008.
[17] S. Lau, and P.C. Cheung,“ Developmental trends of
creativity: What twists of turn do boys and girls take at
different grades?,”Creativity research journal,22(3), pp.
329-336, 2010.
[7] U. Sak and C. J. Maker, “Divergence and convergence of
mental forces of children in open and closed mathematical
problems,” International Education Journal, 6 (2), pp. 252260, 2005.
[18] R. A. Beghetto, “ Creativity in the classroom,in Handbook
of Creativity ,” J. C. Kaufman, and R. J. Sternberg, Eds.
Cambridge, UK: Cambridge University Press, pp.447-463,
2010.
[20] K. H. Kim, “Can We Trust Creativity Tests? A Review of
the
Torrance
Tests
of
Creative
Thinking
(TTCT),”Creativity Research Journal, 18 (1), pp. 3 -14,
2006.
[8] J. P. Guilford, Personality. New York: McGraw-Hill, 1959.
[9]
A.F. Osborn,Applied imagination: Principles and
procedures of creative problem solving. Third Revised
Edition. New York, NY: Charles Scribner’s Sons, 1963.
[21] E. P. Torrance,The Torrance Tests of Creative ThinkingNorms-Technical Manual Research Edition-Verbal Tests,
[10] R. A.Finke, T. B.Wardand Smith, S. M.Smith,Creative
cognition. Cambridge, MA: MIT Press, 1992.
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GSTF International Journal of Law and Social Sciences (JLSS) Vol.1 No.2, July 2012
Forms A and B- Figural Tests, Forms A and B. Princeton,
NJ: Personnel Press, 1974.
Z. Darvishi is a researcher in Shahid
Beheshti University. She obtained a
B.Sc degree in computer engineering
from Mashhad Universtity, Iran and
followed her gradguate studies for
getting M.Sc in philosophy of science
(Sharif University of Technology,
Tehran, Iran ), M.Sc in cognitive
science ( Institute for Cognitive
Science Studies, Tehran, Iran) and
Ph.D in psychology ( Shahid Beheshti
University, Tehran, Iran). Her major
field of study is cognitive psychology
and now, she focuses on creativity and
critical thinking.
[22] A. S. Hosseiniand A. P. Watt, “The effect of a teacher
professional development in facilitating student’ creativity,
”Educational Research and Reviews,5(8), pp. 432-438,
2010.
[23] A. Y. Wang,“ Contexts of Creative Thinking: A
Comparison on Creative Performance of Student Teachers
in Taiwan and the United States, ”Journal of International
and Cross-Cultural Studies, 2, 1, pp. 1- 14, 2011.
[24] Z. Ivcevic and J. D. Mayer, “ CREATIVITY TYPES AND
PERSONALITY , ” IMAGINATION, COGNITION AND
PERSONALITY, . 26 (1-2), pp. 65-86, 2007.
[25] A. J. Cropley, Creativity in education and learning: A
guide for teachers and educators. London: Kogan Page,
pp. 52- 88, 2001.
Sh. Pakdaman is a faculty member in
department of psychology in Shahid
Beheshti University, Tehran, Iran. She
obtained BA and M A in psychology
of exceptional children (Shahid
Beheshti University and Tehran
University, Tehran, Iran) and Ph.D in
psychology ( Tehran University,
Tehran, Iran). Her major fields of
study are developmental psychology
and psychology of exceptional
children.
[26] S. Russ and J. Fiorelli, “ Developmental Approaches to
Creativity,” in The Cambridge Handbook of Creativity, J.
Kaufman and R. Sternberg, Eds. New York: Cambridge
University Press, pp. 233-249, 2010.
[27] M. A. Runco, Creativity: theories and themes: research,
development, and practice, Amsterdam, London: Elsevier
Academic Press, p.101, 2007.
[28] C. Martindale, “ Biological bases of creativity, ” in
Handbook of creativity, R. Sternberg, Ed, Cambridge,
U.K.: Cambridge University Press, pp. 137-152, 1999.
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