Cognitive flexibility in young children: the impact of arousal and temperament by Ecaterina Ciugureanu B.Sc. (Hons.), University of Northern British Columbia, 2011 Thesis Submitted in Partial Fulfillment of the Requirements for the Degree of Master of Arts in the Educational Psychology Program Faculty of Education Ecaterina Ciugureanu 2015 SIMON FRASER UNIVERSITY Summer 2015
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Cognitive flexibility in young children:
the impact of arousal and temperament
by
Ecaterina Ciugureanu
B.Sc. (Hons.), University of Northern British Columbia, 2011
Thesis Submitted in Partial Fulfillment of the
Requirements for the Degree of
Master of Arts
in the
Educational Psychology Program
Faculty of Education
Ecaterina Ciugureanu 2015
SIMON FRASER UNIVERSITY
Summer 2015
ii
Approval
Name: Ecaterina Ciugureanu
Degree: Master of Arts
Title: Cognitive flexibility in young children: the impact of arousal and temperament
Examining Committee: Chair: Shawn Bullock Assistant Professor
Maureen Hoskyn Senior Supervisor Associate Professor
Lucy LeMare Supervisor Professor
David Kaufman Internal/External Examiner Professor
Date Defended/Approved: July 24, 2015
iii
Ethics Statement
iv
Abstract
This study investigated the effects of arousal on cognitive flexibility of young children.
Participants were 119 6-year old children. A within-subjects repeated measures
experimental design was used to evaluate differences in the effect of exposure to threat
and neutral stimuli under low- and high-conflict conditions. On average, children
responded more accurately to threat versus neutral stimuli. Moreover, children
responded slower to threat stimuli relative to neutral stimuli under low-conflict conditions;
however, in high-conflict conditions, differences in reaction time response to stimuli were
not statistically detectible. Children’s self-reported fearfulness towards snakes and
parent-report of children’s general propensity to fearfulness did not moderate response
to threat on the cognitive flexibility task. Findings are discussed within the framework of
the bidirectional model of executive functions and the Yerkes-Dodson law.
Keywords: executive functions; arousal; young children; fearfulness; temperament
v
Dedication
I dedicate this thesis to my beloved grandfather. His
ceaseless pursuit of truth, happiness, and excellence
was both inspiring and infectious.
vi
Acknowledgements
Foremost, I would like to thank my supervisor, Dr. Maureen Hoskyn for her invaluable
advice, astute criticism, and continuous encouragement. It has been an immense growth
opportunity to work with you on this project. I would also like to express my gratitude to
Dr. Lucy LeMare. For your kindness, patience, and guidance, a very heartfelt thank-you.
For his courteous assistance with stimuli and questionnaires, my sincere thanks to Dr.
Ottmar Lipp.
Additional thanks to my nurturing family and friends, the brilliant team members of the
Budding Scientists Research Program, as well as everyone else who helped to make
this a successful project. In addition, I am grateful to Social Sciences and Humanities
Research Council of Canada for supporting this research.
vii
Table of Contents
Approval .......................................................................................................................... ii Ethics Statement ............................................................................................................ iii Abstract .......................................................................................................................... iv Dedication ....................................................................................................................... v Acknowledgements ........................................................................................................ vi Table of Contents .......................................................................................................... vii List of Tables ................................................................................................................. viii List of Figures................................................................................................................. ix
Chapter 1. Introduction ............................................................................................. 1 1.1. Cognitive Flexibility ................................................................................................. 3 1.2. Bidirectional Model of Executive Functions ............................................................. 4 1.3. Cognitive Flexibility, Emotional Arousal, and Emotion Regulation ........................... 7 1.4. Fearfulness ........................................................................................................... 10 1.5. Current Investigation ............................................................................................ 12
Table 3-1. Response to threat and neutral stimuli in the Habituation phase. ........... 24
Table 3-2. Total sample response to threat and neutral stimuli under conditions of low and high conflict. ......................................................... 25
Table 3-3. Adjusted alpha levels on analysis of ECFT accuracy scores. ................. 26
Table 3-4. Children’s self-report and parent-report of child fearfulness.................... 27
Table 3-5. Low fear and moderate-high fear group response to threat and neutral stimuli under conditions of low and high conflict. ........................ 28
Table 3-6. Correlations between child fearfulness and performance under conflict task conditions. .......................................................................... 29
Figure 2-3. All possible trials during the conflict phase. ............................................ 20
Figure 3-1. Interaction effects between conflict and threat on reaction time to correct responses. .................................................................................. 26
1
Chapter 1. Introduction
Our lives frequently draw on our abilities to multi-task, switch between activities,
and adapt to changing circumstances. Furthermore, we are often required to perform
such tasks under emotional arousal, such as stress or excitement. Executive functions
(EFs) refer to a set of cognitive processes that underlie performance on these tasks. EFs
are used in the control of attention, thought, emotions and action, and include planning,
inhibition, working memory and cognitive flexibility (Goldstein, Naglieri, Princiotta, &
Otero, 2014). While an executive system of cognitive resources can be accessed to
control emotional arousal, recent models propose that the system is also influenced by
these automatic processes (Blair & Ursache, 2011). For example, emotional arousal to
threat has been shown to impact cognitive flexibility in adults (Paulitzki, Risko, Oakman,
& Stolz, 2008; Schimmack, 2005); however, it remains unknown whether these relations
hold for young children whose executive systems are emerging (Neuenschwander,
Roebers, & Blair, 2014). The present research aims to address this issue by
investigating the impact of emotional arousal, specifically response to threat, on the
cognitive flexibility of young children.
Three important features of Blair and Ursache’s (2011) bidirectional model of
executive functions highlight its relevance for present research. First, the model predicts
that cognitive flexibility influences and is influenced by emotional arousal in response to
threat; in this way, the relations between cognitive flexibility and emotional arousal in
response to threat are bidirectional and transactional (Luu & Tucker, 2004). Second, the
model is consistent with the Yerkes-Dodson (1908) principle that predicts the effect of
emotional arousal, such as response to threat, on cognitive flexibility is curvilinear.
Robert Yerkes and John Dodson published an article asserting that accuracy of
performance increases with arousal, but only up to a certain point, at which performance
begins to decline. The relationship can be best illustrated by an inverted U shape.
Similarly, Blair and Ursache state that the emotional arousal facilitates performance on
2
EFs tasks up to a certain threshold; however, a very high level of emotional arousal has
a detrimental effect on performance. Third, the model proposes temperament involves a
set of predispositions to focus attention, either automatically or reflexively, and to react
emotionally, either positively or negatively. Emotional reactivity serves as a source of
inter-individual differences in emotional arousal (Neuenschwander et al., 2014). The
latter claim is well supported in the temperament literature (Rothbart, Derryberry, &
2004a). Children with a general propensity to fearfulness may not differ from less fearful
children in their sensitivity to stimuli depicting threat. The lack of association found
between child fearfulness and emotional cognitive flexibility confirms Mogg and
Bradley’s (1998) assertion that hypervigilance to objectively threatening stimuli is
functionally adaptive for all individuals, regardless of their general propensity to fear.
In summary, the present study found evidence in support of the bidirectional
model of EFs (Blair & Ursache, 2011). By finding differences in children’s responses to
threat and neutral stimuli under conditions of low conflict, current findings confirm that
that the executive system is influenced by lower order processes. As this is the first
study of cognitive flexibility and arousal in young children, the present findings
demonstrate that this transactional activity between emotion and the executive system is
present early on in children’s development. At the same time, the findings in the study
also provide evidence to support the long-standing understanding of the EFs as an
36
emotion and behaviour regulation system. When faced with novelty, the executive
system serves a top-down role and allocates cognitive resources such as attention,
equally to novel stimuli, irrespective of level of inherent threat.
Enhanced accuracy in response to threat stimuli confirms the notion that mild
emotional arousal enhances children’s performance on EFs tasks. However, it must be
noted that the speed-accuracy trade off found in the low conflict condition of the ECFT
demonstrates that performance on complex executive function tasks is multifaceted, and
as such may not perfectly adhere to the curvilinear pattern predicted by the bidirectional
model of EFs and the Yerkes-Dodson law. Additionally, the lack of statistical differences
in reaction time to responses to neutral- and mild threat stimuli in the Habituation phase
or under conditions of high conflict in the Conflict phase of the ECFT highlights the
complexity of relations between emotional arousal and cognitive flexibility. As proposed
by Kagan and Snidman (2009), exposure to unfamiliar stimuli may invoke emotional
arousal. Differences in the effects of different sources of emotional arousal and their
differential effects on children’s performance is a factor not previously considered in the
bidirectional model of executive functions or the Yerkes-Dodson law.
This study also aimed to investigate the relationship between child fearfulness
and cognitive flexibility under conditions of mild threat. In contrast to previous findings
with adults, no differences emerged between children who self-reported moderate to
high level of specific fear toward the threat stimuli and those reported low level of
specific fear toward threat stimuli. As children in the study had little experience and
exposure to snakes, their self-reported feelings of fearfulness towards snakes may not
translate to how they will behave in the presence of snakes. Moreover, the present study
also demonstrated a lack of association between children’s general propensity to fear
and cognitive flexibility under conditions of mild threat, confirming findings from previous
research that has investigated these relations with other cognitive measures. As
objectively threatening stimuli is functionally adaptive for all individuals, temperament
may have little effect on the executive system under such conditions.
This study has a number of implications. Firstly, it adds to the growing literature
on the effects of emotion on cognitive flexibility in early childhood. As informed by the
37
bidirectional model of EFs, lower order and higher order processes both play a role in
explaining these effects reported in this study. Another implication of this research is the
effects of novelty must be considered when designing cognitive flexibility tasks for young
children. Finally, this study contributed to research that aims to link children’s general
fearfulness with other aspects of cognition. Findings reported here suggest that
children’s temperament, specifically their propensity to fearfulness, is not associated with
their ability to flexibly attend to rules under conditions of emotional arousal to threat.
There were several limitations to the present study. First, the picture stimuli
served as only a mild threat, and as such may not have elicited significant levels of
arousal to affect performance on the ECFT across all conditions. Second, a behavioural
measure of child fearfulness may have produced different effects than those found when
parent- and child- report measures were used. Third, the study could be interpreted as
having low ecological validity because performance on the ECFT was not associated
with parent-report of child behaviour in real world settings. Further research that
associates ECFT performance with direct measures of child behaviour is needed.
38
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