To what extent do low effortful control skills and high
impulsivity in 2.5-year-old children predict aggressive
behavior at 4.5 years of age?
Masterthesis Forensische Orthopedagogiek Graduate School of Child Development and Education University of Amsterdam Denise Nijs: 10673733 Mrs. dr. M. Majdandžić Ms. dr. H.E. Creemers Amsterdam, July 2015
Abstract
Aggression is a personality trait which stabilizes around 4 years of age (Anderson &
Bushman, 2002; Broidy et al., 2003). In order to prevent externalising problem behavior (in adolescence) from developing, being aware of risk factors is key (Nagin & Tremblay, 1999; Putnam, 2011). In this study it was examined to what extent high impulsivity and low effortful control in 2.5-year-olds contribute to more aggressive behavior at 4.5 years. The scores of 120 families were used in this study. When the child was 2.5 years old, parents filled in the Early Childhood Behavior Questionnaire (ECBQ; Putnam, Gartstein, & Rothbart, 2006) to measure the levels of impulsivity and effortful control of their child. The level of
aggression was measured by the Social Competence and Behavioral Evaluation-30
questionnaire (SCBE30; LaFreniere & Dumas, 1996) at 4.5 years old. Results showed that low effortful control skills at 2.5 predicted more aggressive behavior at 4.5 years old. High impulsivity did not significantly predict more aggression, but the relationship between low effortful control and the levels of aggression was moderated by impulsivity. For children high in impulsivity the level of aggression was related to effortful control, whereas for children low in impulsivity aggression was not related to effortful control. These findings provide evidence that low effortful skills and high impulsivity are important (risk)factors in the development of aggressive behavior.
Contents
Introduction 4 Methods 10 Participants 10 Procedure 11 Measures 12 Temperament 12Externalising Problem Behavior 13
Data analyses 14 Results 14 Preliminary analyses 14 Regression analyses 15 Discussion 18 References 22
Introduction
High impulsivity and low effortful control seem to be risk factors and increase the likelihood of deviant aggressive behavior (Eisenberg, Spinrad, & Eggum, 2010a; Kochanska, Coy, & Murray, 2001). By examining these temperament dimensions and the onset of aggressive behavior in early childhood, signs of abnormal behavior can be identified and responded to effectively in order to prevent deviant aggressive behavior in the future. Being aware of these signs and risk factors enables us to intervene as soon as possible. This is important because it is more difficult to change a persister's mindset than it is to change a first offender's mindset (Hill, 2003; Piquero, Farrington, Welsh, Tremblay, & Jennings, 2009). In addition, prevention is much cheaper than repressive means (Van de Bunt & Van der Sloot, 2003).
In order to study the relationship between impulsivity, effortful control and
aggression, it is important to define these dimensions. First, Putnam, Gartstein and Rothbart (2006) state that the temperament dimension impulsivity has to do with the speed of response initiation. Impulsivity as a temperament trait refers to “actions that are poorly conceived, prematurely expressed, unduly risky, or inappropriate to the situation and that often result in undesirable outcomes” (Daruna & Barnes, 1993, p. 23). Impulsiveness as a personality type comprises persons who tend to talk before they think, who give in sooner, are bored easily and have poor inhibitory control systems compared to non-impulsive persons (Buss & Plomin, 1975; Zuckerman & Kuhlman, 2000). They are also more careless in situations that require more attention and if there is no direct gratification or reward for their effort, they are less likely to persevere compared to non-impulsive persons (Cloninger, 1987; Zuckerman & Kuhlman, 2000).
Ramírez and Andreu (2006) state that impulsivity is in fact the 'uncivilized response' followed from an emotional event/situation. Learning to control these primary responses, to overthink an impulsive response and to react adequately to an (emotional) situation is called
conforming. People who experience more problems with conforming keep responding impulsively and that often results in (negative) unwanted outcomes (Evenden, 1999). Barrat (1991) found that irrespective of the nature of the crime, most criminals showed high levels of impulsiveness. It seems that high levels of impulsiveness are a risk factor for deviant
(criminal) behavior (Barrat, 1991; Evenden, 1999; Ramírez & Andreu, 2006).
In reaction to the study of Barrat (1991), Vigil-Colet, Morales-Vives, and Tous (2008) also studied the relation between impulsivity and aggression, but across different samples. Teenagers, university students and workers participated in this study and were asked to fill in two questionnaires, the Spanish adaptations of the Dickman's Impulsivity Inventory (DII) and the Buss and Perry Aggression Questionnaire (AQ). These questionnaires measure
impulsivity and aggressiveness, respectively. Vigil-Colet and colleagues (2008) found that impulsivity and aggression were related across these different samples. So irrespective of age, socioeconomic status or gender, a positive correlation between impulsivity and aggression has been found in multiple samples of the general population and this relation is not limited to the criminal population.
The study of McMurran, Blair and Egan (2002) showed that impulsivity was directly related to poorer problem-solving skills and poor problem-solving skills were directly related to aggressive behavior and drinking problems. High impulsivity thus seems to prevent persons from developing adequate problem solving skills necessary to cope with difficult situations (McMurran, Blair, & Egan, 2002). Lacking these problem-solving skills results in less civilized, more basic responses such as aggression (Anderson & Bushman, 2002). Thus, evidence demonstrates that impulsivity increases the risk for developing aggressive problem behaviors, both directly and via preventing the development of adequate problem solving skills.
Secondly, the temperament dimension effortful control refers to “the efficiency of executive attention– including the ability to inhibit a dominant response and/or to activate a subdominant response, to plan, and to detect errors” (Rothbarth & Bates, 2006, p.129). Research shows that effortful control is developed and learned over time (Eisenberg et al., 2010b). Focused attention can be seen in children from 8 to 10 months old; the attention-span is then still fairly short but as the child grows, the attention-span will become larger
(Kochanska, Coy, Tjebkes, & Husarek, 1998; Kannass et al., 2006; Ruff & Capozzoli, 2003). A more difficult skill such as effortfully inhibiting behavior develops at a later stage in life (24 to 36 months; Gerardi-Caulton, 2000). Focusing and shifting attention, inhibiting inappropriate behavior and doing things that you would rather avoid are abilities that characterize effortful control (Eisenberg et al., 2010a).
Like high impulsivity, low effortful control is also associated with more aggression problems (Eisenberg et al., 2010a). Especially attention regulation and inhibitory control are components of effortful control that have been related to aggressive, destructive and
oppositional behavior (Hill, Degnan, Calkins, & Keane, 2006). The ability to regulate attention and to inhibit primary responses is important because they help to cope with emotional, stressful situations and decrease stress levels. Without adequate regulation knowledge and strategies an overaroused/stressed child is more likely to react the only way he/she knows, namely by responding directly according to its negative emotions, which increases the risk of aggressive behavior (Hill et al., 2006; Spinrad et al., 2007).
In the longitudinal study of Eiden, Edwards and Leonard (2007) the relation was explored between parental sensitivity at 2 years old, the level of effortful control at 3 years old and externalising problem behavior in kindergarten at age 5-6 (n = 227). They found that fathers who were sensitive towards their children at age 2 (measured through observing the parent and child playing in a room for 10 minutes), predicted the development of higher levels
of effortful control in their children at age 3. To measure the level of effortful control the child was observed in a delay of gratification test, a whisper test and a lab gift test. Externalising problem behaviors were rated by teachers and parents through the Child
Behavior Checklist (CBCL; Achenbach, 1991). They found that the better the effortful control skills were developed at age 3, the less externalising problem behaviors the children had at age 5-6 (Eiden et al., 2007).
In another longitudinal study Kim, Nordling, Yoon, Boldt and Kochanska (2013) determined the levels of effortful control in children at 38 and 52 months old (n = 100), by scoring the performance of the child in delay of gratification tasks, where the children were asked to wait before eating a snack or opening a gift-wrap. Their behavior such as peeking and touching was coded and latencies were measured. In these tasks, the children had to rely heavily on their emotional regulation capacities. Then, at 67, 80 and 100 months, the parents and teachers were asked to fill in some questionnaires about behavioral problems and
academic performances of the child. Kim and colleagues (2013) found that the inability to regulate emotions and to inhibit unwanted behavior at 38 and 52 months old were related to externalising problem behavior at the ages 5 to 8.
Crockenberg, Leerkes and Bárrig Jó (2008) even found that aggression seems to be related to a precursor of effortful control, that is, the direction of attention in early infancy (Eisenberg et al., 2009). In this study mothers and their infants were observed at 6 months (n = 64). The direction of attention in infants who kept watching frustrating events (instead of looking the other way) was positively related to aggression at 2.5 years old.
There are few studies examining the relationship between the constructs effortful control and impulsivity. More studies focus on the relation between one component of effortful control (e.g. inhibitory control, attention focusing) and impulsivity such as the study of Logan, Schachar and Tannock (1997). They examined the relation between inhibitory
control and impulsivity in 136 students. The students were given an impulsivity questionnaire where their impulsivity levels were assessed on a scale of 1 to 9. Then they participated in a stop-signal paradigm where they had to inhibit their responses when they heard a stop-signal on a go task. As expected, the reaction time to the stop-signal was larger for impulsive participants than for non-impulsive participants, indicating that impulsive persons tend to have problems with inhibiting prepotent responses (Logan et al., 1997).
The only studies examining the interaction between effortful control, impulsivity and externalising problem behaviors were conducted by Eisenberg and colleagues (Eisenberg et al., 2004; Eisenberg et al., 2005; Eisenberg et al., 2009). In one of the studies, children aged between 4.5 to 8 years and their parents (n = 214) visited the lab, the parents were asked to fill in questionnaires on the child's behavior and temperament (CBQ and CBCL), while the child was assessed in the lab to measure his/her self-regulation skills (doing a puzzle) (Eisenberg et al., 2004). The teacher of the child also rated the child's behavior problems. Eisenberg and colleagues (2004) found that impulsivity did not significantly correlate to effortful control, which provides support for the notion that these are two different constructs (Taylor, 1990). They also found that both impulsivity and low effortful control were related to externalising problem behavior. To measure externalising problem behavior, aggression and delinquency items from the CBCL (Achenbach, 1991) were used. The correlations were even stronger when the child was prone to anger (ages 4.5 to 8 years old).
In a follow-up study, Eisenberg et al. (2005) assessed the results of 185 children (now 6.5 to 10 years of age), parents and teachers. Questionnaires on the child's behavior and temperament were filled in by the teacher and the parents of the child and the child's self-regulation was measured by a skin conductance task where the child was asked to sit still until the experimenter came back, and in another task the child was asked to do a puzzle. Eisenberg et al. (2005) found that children with high levels of impulsivity and low effortful control at
age 6.5 to 10 also demonstrated higher levels of aggression and delinquent behavior especially when the child was prone to anger. The same results were found in the study of Eisenberg and colleagues (2009) in which 214 children (M age = 73 months), parents and teachers participated. Thus, these studies of Eisenberg et al. (2004; 2005; 2009) showed similar results: high impulsivity and low effortful control predicted higher levels of aggression and delinquency (Eisenberg et al., 2009) which is considered externalising problem behavior (Eisenberg et al., 2004; 2005; 2009; Kim & Deater-Deckard, 2011).
Lastly the definition of the dimension aggression, which refers to “any behavior directed toward another individual that is carried out with the proximate (immediate) intent to cause harm” (Anderson & Bushman, 2002, p.28). Many studies have found that aggression is rather stable throughout life (Nagin & Tremblay, 1999; Anderson & Bushman, 2002; Broidy et al., 2003; Putnam, 2011). Early childhood aggression in boys is common and age-related (2-3-year-olds), but aggression at the age of 4.5 is often related to other problems (i.e. lack of effortful control skills) which increases the risk of future problem behavior (Nagin &
Tremblay, 1999; Putnam, 2011). Studies examining the onset of aggression are important because it enables parents to be aware of deviant behavior and correct the behavior on time (Hill, 2003; Piquero et al., 2009; Van de Bunt & Van der Sloot, 2003).
In the current longitudinal study, the relations between effortful control, impulsivity and aggression were examined. Even though there is much knowledge about the individual dimensions impulsivity, effortful control and aggression, only Eisenberg and colleagues (2004; 2005; 2009) examined relationships between effortful control, impulsivity and aggression and delinquent behavior. Based on the results of their studies it was evident that high impulsivity and low effortful control were related to subsequent externalising problem behaviors.
In this study it was examined whether aggression in 4.5-year-olds could be predicted from impulsivity and effortful control measured at 2.5 years old and if the interaction between impulsivity and effortful control predicted more aggression than these dimensions do
individually. The relations between those variables have never been examined in children this young, but it is important to examine this because if these relations hold at these young ages, risk factors of deviant behavior could be detected and responded to very early on. In the current study it was predicted that high impulsivity and low effortful control at 2.5 years old were related to more aggression at 4.5 years. The interaction between high impulsivity and low effortful control was predicted to be related to even more aggression at 4.5 years because lacking the necessary skills to cope with stressful situations (low effortful control) and not being able to calmly assess it and respond to it in an appropriate manner (high impulsivity) are two risk factors that amplify eachother and turn into a recipe for more anger/frustration and eventually aggression (Buss & Plomin, 1975; Zuckerman & Kuhlman, 2000; Hill et al., 2006; Spinrad et al., 2007).
Method
Participants
The data used for this thesis are retrieved from a study that consists of 120 children and their parents. These children and their parents participated in a longitudinal study: The social development of children, which focused on social anxiety. The study started in 2007 and is still an ongoing project, it is carried out by the University of Amsterdam. Families were recruited through leaflets provided by midwives in Amsterdam and cities within a range of 50 kilometres around Amsterdam, at pregnancy courses in Amsterdam, and at baby shops, and through advertisements in magazines and on websites on parenthood and they received a 20 euro voucher after fully participating in a measurement.
There were four measurements that took place at 4 months, 1 year, 2.5 years and 4.5 years. The children were 2.5 years at measurement T3 (SD = 0.05, 18 days) and 4.5 years of age at measurement T4 (SD = 0.05, 20 days). The sample consisted of 44.2 % boys (n = 53) and 55.8 % girls (n = 67).
The mother's mean age was 34.02 years (SD = 4.17) at T3 and 36.07 years (SD = 4.24) at T4. Father's mean age was 36.94 years (SD = 5.40) at T3 and 39.11 years (SD = 5.47) at T4. The social economic status of the participating families was measured through level of
education and career level. The average level of education of the parents was for the mothers
M = 7.07 (SD = 1.12) and the fathers M = 6.63 (SD = 1.56) on a scale from 1 = primary
education, to 8 = University. The average career level was for mothers M = 8.71 (SD = 2.15) and for fathers M = 8.25 (SD = 2.66) ranging from 1 (manual labor for which no education is required) to 11 (labor for which a university degree is required). Both educational and career level are thus fairly high. Most participants were of Dutch origin (95.0% of men and 91.7% of women).
Procedure
At each measurement mother and father separately visited the research centre at the Research Institute of Child Development and Education of the University of Amsterdam with their child, and there was a house visit when the child was 2.5 years of age. During the measurements in the lab, several tasks were conducted with the parents and the children and every task was recorded with video cameras from behind a one-way window. During the house visit the parents and children were filmed in their own environment while doing different tasks.
The data used in the current study were from questionnaires that the parents filled in at home. They received the questionnaires shortly before the lab measurements.
Measures
Temperament. At child age 2.5 years, effortful control and impulsivity of the child
were measured using the Early Childhood Behavior Questionnaire (ECBQ, Putnam, Gartstein, & Rothbart, 2006). This questionnaire consists of 201 items and eighteen scales which
together give an overview of the child’s temperament. Through factor analysis Putnam and colleagues (2006) found that these eighteen scales could be divided into three factors, Negative Affectivity, Surgency-Extraversion and Effortful Control. In this study the short version of the ECBQ was used, consisting of 107 items and 18 scales. In this study, effortful control was measured through the scales attentional focusing (6 items): “When playing alone, how often did your child play with a set of objects for 5 minutes or longer at a time?”,
attention shifting (8 items): “When engaged in play with his/her favorite toy, how often did your child continue to play while at the same time responding to your remarks or questions?”, cuddliness (6 items): “When your child was carried, how often did he/she snuggle up next to you?”, low-intensity pleasure (6 items): “During daily or evening quiet time with you and your child, how often did your child enjoy just being talked to?” and inhibitory control (6 items): “When asked to do so, how often was your child able to be careful with something breakable?”. Impulsivity was assessed through the impulsivity scale (4 items): “When offered a choice of activities, how often did your child decide what to do very quickly and go after it?”. The items were rated on a 7-point Likert-scale (never, almost never, less than half of the time, approximately half of the time, more than half of the time, almost always, always) and an extra option 'not applicable' that is filled in when the described situation had not occurred in the past two weeks. High scores on a temperament scale represents high levels of that specific temperament characteristic. The internal consistencies of the scales were adequate in the present study (Table 1). The correlation between mother and father reports for effortful control was r = .88, p < .001. The correlation between mother and father reports for
impulsivity is r = .65, p = .03. Because of significant correlations between mother and father reports on the different factors, the scores of fathers and mothers were averaged.
Externalising problem behavior. Aggression of the child was measured at 4.5 years
using the Social Competence and Behavioral Evaluation-30 (SCBE30, LaFreniere & Dumas, 1996). This is an abridged, validated version of the original 80-item SCBE (Myaing, Garrison, Rivara, & Christakis, 2011). Parents were asked to fill in the parent version of the SCBE-30 and answered the 30 questions about the child’s behavior rated with a 4-point scale (never- sometimes- often- always). Different items measured patterns of anger-aggression, anxiety-withdrawal or social competence in preschool-aged children. In the current study, the anger-aggression scale was used, consisting of 10 items: “My child gets angry when disturbed”.
Kotler and McMahon (2002) found that the parent version of the SCBE-30 has many similarities with the teacher version of the SCBE-30 that was validated by LaFreniere and Dumas (1996). Results demonstrated internal consistency and construct validity (Kotler & McMahon, 2002). The correlation between mother and father reports for anger-aggression is r = .81, p < .001 (Table 1). Due to this correlation between mother and father reports, the scores were averaged into one score for aggression.
Table 1
Cronbach's Alpha's of the Scales Measured for Mothers and Fathers Separately
Scale Mother Father
Impulsivity Attentional Focussing .57 .84 .59 .76 Attentional Shifting .70 .58 Cuddliness .82 .75 Inhibitory Control .79 .75
Low Intensity Pleasure .66 .68
Effortful Control
.88 .86
Data analyses
The data was analysed using SPSS. To answer the research questions multiple regression analyses were performed to establish what the effect was of multiple independent variables on the dependent variable (α = .05). The temperament scales (impulsivity and effortful control factors) were the independent variables and externalising problem behavior (aggression) was the dependent variable. With the multiple regression analysis we also determined if the interaction between impulsivity and effortful control predicted more
aggression than these dimensions do individually. To do that, the variables were standardised and multiplied so that they could be incorporated as a predictor in the regression model.
Results
Preliminary Analyses
In total four parents (3.3%) did not complete the ECBQ at 2.5 years and 10 parents (8.3%) did not complete the SCBE-30 at 4.5 years. Parents who dropped out were examined for
educational and career level. Dropout mothers did not differ significantly in educational level (M = 7.33, SD = 0.65) from mothers who did not drop out (M = 7.04, SD = 1.16; t(114) = -0.87, p = .39). Also the career level of dropout mothers was not significantly different (M = 8.46, SD = 2.37) from mothers who continued to participate in this study (M = 8.74, SD = 2.13; t(118) = 0.44, p = .66). The same results were found in fathers. Dropout fathers did not differ significantly in educational (M = 6.75, SD = 1.42) or career level (M = 9.17, SD = 2.08) from fathers who did not drop out (educational level M = 6.62, SD = 1.58; t(117) = -0.28, p = .80 and career level M = 8.15, SD = 2.71; t(117) = -1.26, p = .07). The drop out families were also examined for the child's impulsivity level, effortful control and aggression. No
effortful control and aggression, but dropouts showed significantly lower impulsivity levels (M = 3.66, SD = 0.68) compared to the families that continued to participate in the study (M = 4.29, SD = 0.78; t(114) = 2.36, p = .02).
For 106 families the data was complete (i.e. the ECBQ was filled in at T3 (2.5 year measurement) and the SCBE-30 at T4 (4.5 year measurement) by both parents). According to the outlier labeling rule (Hoaglin, Iglewicz, & Tukey, 1986) there were no outliers in the data (M +/- 2.20 SD).
The correlations between the variables were examined. The variables impulsivity - effortful control and impulsivity – aggression were not significantly correlated (Table 2). Effortful control and aggression did correlate significantly.
Table 2
Correlations between Impulsivity, Effortful Control and Aggression
1 2 1. Impulsivity 2. Effortful Control -.15 3. Aggression .12 -.40** Note. * p < .05, ** p < .01 (2-tailed) Regression Analyses
It was expected that high impulsivity and low effortful control skills at 2.5 years of age, predicted higher levels of aggressive behavior at 4.5 years, and that the interaction between high impulsivity and low effortful control would lead to even larger scores in aggressive behavior in 4.5-year-olds than these dimensions do individually.
The regression model with the dependent variable aggression and the independent variables effortful control and impulsivity was significant F(2,103) = 9.97; p < .001.
Adding the interaction impulsivity*effortful control to the model F(3,102) = 8.29; p = .04 explained another 3.4% of the variance (R² = .196; Table 3).
The first regression model showed that low effortful control at 2.5 years old was related to higher levels of aggression in 4.5-year-olds (β -.39, SE = 0.10, p < .001).
Impulsivity at 2.5 years old was not related to higher levels of aggression (β .05, SE = 0.09, p = .57). The second regression model showed that a significant interaction was found.
Table 3
The Influence of Impulsivity, Effortful Control and their Interaction on Aggression (N=106)
Independent variable Beta p
Step 1 (R2 ,R2adj) (.16, .15) <.001
Impulsivity .05 .57
Effortful Control -.39 <.001
Step 2 (R2 ,R2adj ,R2change) (.20, .17, .03) .04
Impulsivity .04 .64
Effortful Control -.36 <.001
Impulsivity*Effortful Control
-.19 .04
Additional analyses were done and the median of the impulsivity scores was calculated. Children with an average score of 4.25 or less (on a 1-7 scale) were
categorized as the “low impulsivity” children. Children with an average score higher than 4.25 were considered to be “highly impulsive”. Regression analyses were done with effortful control as a predictor of aggression. Results showed that for children with low levels of impulsivity, effortful control was not associated with aggression levels (β -.26,
SE = 0.14, p = .07; Fig 1). For children high in impulsivity, effortful control was
Fig. 1 Joint Effect of Effortful Control and Impulsivity on Aggression Low Effortful Control High Effortful Control
-0.8 -0.6 -0.4 -0.2 0 0.2 0.4 0.6 0.8 Low Impulsivity High Impulsivity A g g re ssi o n
Discussion
Aggression is negative behavior that is often related to underlying problems (Loeber & Hay, 1997; Denson, DeWall, & Finkel, 2012). This study examined to what extent impulsivity and effortful control in 2.5-year-olds are related to aggression at 4.5 years old. Results reveal that low levels of effortful control skills in toddlerhood increase the risk of developing aggressive behavior two years later, but especially the interaction of high impulsivity and low effortful control skills increases this risk. Impulsivity was not found to to have a significant direct impact on the level of aggression.
Even though impulsivity and aggression are not significantly related in this study, Vigil-Colet, Morales-Vives, and Tous (2008) found that irrespective of the population sample, high impulsivity was related to more aggressive behavior. According to McMurran, Blair and Egan (2002) this is because impulsivity is directly related to poor (undeveloped) problem solving skills (mediating factor) which in turn is correlated to more aggressive behavior. Previous research has also shown that most criminals are more impulsive compared to the non-criminal population regardless of the nature of their crime (Barrat, 1991; Evenden, 1999; Ramírez & Andreu, 2006). So despite the (lack of) findings in the current study, other
research did find impulsivity to be a risk factor for aggressive, deviant and even criminal behavior (Barrat, 1991; Evenden, 1999; Ramírez & Andreu, 2006; Vigil-Colet, Morales-Vives, & Tous, 2008). It is possible that no relation was found between impulsivity and aggression because internal consistency of the impulsivity scale was only modest. It is plausible that the items in the impulsivity scale measure the same construct (impulsivity), but in future studies it would be recommended to use a larger impulsivity scale (not a 4-item scale) to increase its internal consistency in order to better measure the correlation between impulsivity and aggression. Another explanation could be that the level of impulsivity is fairly high in 2.5-year-olds and gradually decreases with age (Deák, Ray, & Pick, 2004; Turner,
1991). Due to already high levels of impulsivity a significant result might not be found (Akshoomoff, 2002; Deák, Ray, & Pick, 2004).
As shown in other research (Eden, Edwards, & Leonard, 2007; Kim et al., 2013), this study also found that effortful control skills and aggression are related. Children with low effortful control skills at 2.5 years old showed more aggressive behavior at 4.5 years old and high effortful control skills are related to less aggressive behavior. Effortful control skills are necessary in order to be able to regulate emotional and stressful situations (Hill et al., 2006; Spinrad et al., 2007). Lacking effortful control skills in these situations raises the probability that more primitive (aggressive) behavior will be expressed (Hill et al., 2006). Thus, levels of aggression at age 4 can already be predicted by the level of effortful control at 2.5 years of age. This is an important result because being aware of (the onset of) factors contributing to the development of aggressive behavior enables us to address it in time.
As expected, children with low effortful control skills and high impulsivity at 2.5 years old showed even more aggression at 4.5 years old than children with only low effortful control skills or high impulsivity. In fact, the level of effortful control was only significantly related to aggression when the child had high impulsivity. High effortful control skills seem to be protective factors for aggression. The results found in this study reveal that it is possible to predict levels of aggression in 4.5-year-olds by measuring the levels of effortful control and impulsivity in children at 2.5 years old. Especially children with low effortful control and high impulsivity belong to the at-risk children. Because most studies have found that aggression is stable around 4 years old (Nagin & Tremblay, 1999; Anderson & Bushman, 2002; Broidy et al., 2003; Putnam, 2011), it is essential that the interactions between
impulsivity, effortful control and aggression will be further examined in order to understand the causal relations, intervene and correct the child's behavior as soon as possible. Reducing levels of impulsivity at this young age should not be the focus of attention because
impulsivity is partly age-related, mostly these levels will reduce over time anyhow (Deák, Ray, & Pick, 2004; Turner, 1991). Improving effortful control skills on the other hand will always benefit the child (Hill et al., 2006; Spinrad et al., 2007; Eden, Edwards, & Leonard, 2007; Kim et al., 2013). As was found in the study of Eiden, Edwards and Leonard (2007), children with sensitive parents had better developed effortful control skills at the age of 3, compared to children with insensitive parents. Interventions are therefore recommended to focus on this sensitivity between parents and children and the child's self-regulation skills. An intervention that could be considered is the basic trust method (Polderman, 1998). The focus of this intervention is on families with 2- to 5-year-olds where parents learn to understand the child's needs and to sensitively act upon these needs, which in turn helps the child to develop more/better self-regulation skills. As stated earlier, it is cheaper and more effective to
intervene when problems arise than to intervene when problem behavior has become persistent (Hill, 2003; Piquero et al., 2009; Van de Bunt & Van der Sloot, 2003).
There are several limitations that have to be taken into account. First, the impulsivity scale consisted of four items and fathers’ and mothers’ scores of their child’s impulsivity correlated at trend level. The internal consistency of impulsivity was nearly acceptable and to get a better estimate of the impulsivity of the child the scores of both parents were averaged. Including more items in the impulsivity scale is recommended. Second, although this is a longitudinal study where data from the 2.5 and 4.5 year measurement were used, it is not an experimental study. Therefore, causal relationships remain difficult to infer. For example, even though low effortful control skills seem to predict aggression, it cannot be excluded from this study that aggression (also) influences the development of effortful control skills (Fox & Calkins, 2003). Another limitation was that all the data was obtained from questionnaires, no observations were used. In order to measure the variables more objectively it is recommended that observations are used and compared to the scores retrieved from the questionnaires.
Lastly, the sample consisted of parents with rather high career and educational levels. Whether the results can be generalized to the general population is uncertain.
In conclusion, this study focussed on the question to what extent effortful control skills and impulsivity in 2.5-year-olds predicted aggressive behavior at 4.5 years old. It was found that effortful control only influenced the level of aggression when the child had high levels of impulsivity. These results can be explained because effortful control skills are necessary in order to cope in an appropriate (non-aggressive manner) when confronted with emotional, stressful situations (Hill et al., 2006; Spinrad et al., 2007). High impulsivity is related to attention difficulties and bad assessment skills, which are factors that all increase the risk of deviant (criminal) behavior (Buss & Plomin, 1975; Zuckerman & Kuhlman, 2000). Children with high impulsivity and low effortful control are lacking the necessary skills to react in any other way but emotional. It is therefore no surprise that the levels of aggression will be higher in these children. Future research should focus on the causal relations between these variables so that adequate interventions can be developed and applied when necessary, because
preventing persistent aggressive/deviant behavior from developing is always better than 'curing' it.
References
Achenbach, T. M. (1991). Manual for the Child Behavior Checklist/4–18 and 1991 profile.
Burlington: University of Vermont, Department of Psychiatry.
Akshoomoff, N. (2002). Selective attention and active engagement in young children. Developmental Neuropsychology, 22(3), 625-642.
Anderson, C. A., & Bushman, B. J. (2002). Human aggression. Psychology, 53(1), 27-51. Barratt, E. S. (1991). Measuring and predicting aggression within the context of a personality
theory. Journal of Neuropsychiatry and Clinical Neurosciences, 3(2), 35-39.
Broidy, L. M., Nagin, D. S., Tremblay, R. E., Bates, J. E., Brame, B., Dodge, K. A., ... Vitaro, F. (2003). Developmental trajectories of childhood disruptive behaviors and
adolescent delinquency: A six-site, cross-national study. Developmental Psychology, 39(2), 222-245.
Bunt, Van de, H. G., & Schoot, Van der, C. R. A. (2003). Prevention of organised crime. Boom.
Buss, A. H., & Plomin, R. (1975). A temperament theory of personality development. Wiley, New York.
Cloninger, C. R. (1987). A systematic method for clinical description and classification of personality variants. Archives of General Psychiatry, 44(6), 573-588.
Crockenberg, S. C., Leerkes, E. M., & Bárrig Jó, P. S. (2008). Predicting aggressive behavior in the third year from infant reactivity and regulation as moderated by maternal behavior. Development and Psychopathology, 20(1), 37-54.
Daruna. J. H., & Barnes, P. A. (1993). A neurodevelopmental view of impulsivity. In: W. G. McCown, J. L. Johnson, M. B. Shure (Eds), The impulsive client: Theory, research
Deák, G. O., Ray, S. D., & Pick, A. D. (2004). Effects of age, reminders, and task difficulty on young children’s rule-switching flexibility. Cognitive Development, 19(3), 385-400.
Denson, T. F., DeWall, C. N., & Finkel, E. J. (2012). Self-control and aggression. Current
Directions in Psychological Science, 21(1), 20-25.
Eiden, R. D., Edwards, E. P., & Leonard, K. E. (2007). A conceptual model for the development of externalizing behavior problems among kindergarten children of alcoholic families: Role of parenting and children's self-regulation. Developmental
Psychology, 43(5), 1187-1201.
Eisenberg, N., Sadovsky, A., Spinrad, T. L., Fabes, R. A., Losoya, S. H., Valiente, C., ... & Shepard, S. A. (2005). The relations of problem behavior status to children's negative emotionality, effortful control, and impulsivity: Concurrent relations and prediction of change. Developmental Psychology, 41(1), 193-211.
Eisenberg, N., Spinrad, T. L., & Eggum, N. D. (2010a). Emotion-related self-regulation and its relation to children’s maladjustment. Annual Review of Clinical Psychology, 6, 495-525.
Eisenberg, N., Spinrad, T. L., Eggum, N. D., Silva, K. M., Reiser, M., Hofer, C., ... & Michalik, N. (2010b). Relations among maternal socialization, effortful control, and maladjustment in early childhood. Development and Psychopathology, 22(3), 507-525.
Eisenberg, N., Spinrad, T. L., Fabes, R. A., Reiser, M., Cumberland, A., Shepard, S. A., ... & Thompson, M. (2004). The relations of effortful control and impulsivity to children's resiliency and adjustment. Child Development, 75(1), 25-46.
Eisenberg, N., Valiente, C., Spinrad, T. L., Cumberland, A., Liew, J., Reiser, M., ... & Losoya, S. H. (2009). Longitudinal relations of children’s effortful control,
impulsivity, and negative emotionality to their externalizing, internalizing, and co-occurring behavior problems. Psychology, 45(4), 988-1008.
Evenden, J. L. (1999). Varieties of impulsivity. Psychopharmacology, 146(4), 348-361. Fox, N. A., & Calkins, S. D. (2003). The development of self-control of emotion: Intrinsic
and extrinsic influences. Motivation and Emotion, 27(1), 7-26.
Gerardi-Caulton, G. (2000). Sensitivity to spatial conflict and the development of self-regulation in children 24–36 months of age. Developmental Science, 3(4), 397-404. Hill, J. (2003). Early identification of individuals at risk for antisocial personality disorder.
British Journal of Psychiatry, 182(44), 11-14.
Hill, A. L., Degnan, K. A., Calkins, S. D., & Keane, S. P. (2006). Profiles of externalizing behavior problems for boys and girls across preschool: The roles of emotion regulation and inattention. Developmental Psychology, 42(5), 913-928.
Hoaglin, D.C., Iglewicz, B., and Tukey, J.W. (1986). Performance of some resistant rules for outlier labeling. Journal of American Statistical Association, 81(396), 991-999.
Kannass, K. N., Oakes, L. M., & Shaddy, D. J. (2006). A longitudinal investigation of the development of attention and distractibility. Journal of Cognition and Development,
7(3), 381-409.
Kim, J., & Deater-Deckard, K. (2011). Dynamic changes in anger, externalizing and internalizing problems: Attention and regulation. Journal of Child Psychology and
Psychiatry, 52(2), 156-166.
Kim, S., Nordling, J. K., Yoon, J. E., Boldt, L. J., & Kochanska, G. (2013). Effortful control in “hot” and “cool” tasks differentially predicts children’s behavior problems and academic performance. Journal of Abnormal Child Psychology, 41(1), 43-56.
Kochanska, G., Coy, K. C., & Murray, K. T. (2001). The development of selfregulation in the first four years of life. Child Development, 72(4), 1091-1111.
Kochanska, G., Coy, K. C., Tjebkes, T. L., & Husarek, S. J. (1998). Individual differences in emotionality in infancy. Child Development, 69(2), 375-390.
Kotler, J. C., & McMahon, R. J. (2002). Differentiating anxious, aggressive, and socially competent preschool children: Validation of the Social Competence and Behavior Evaluation-30 (parent version). Behaviour Research and Therapy, 40(8), 947-959. LaFreniere, P. J., & Dumas, J. E. (1996). Social competence and behavior evaluation in
children ages 3 to 6 years: The short form (SCBE-30). Psychological Assessment, 8(4), 369-377.
Loeber, R., & Hay, D. (1997). Key issues in the development of aggression and violence from childhood to early adulthood. Annual Review of Psychology, 48(1), 371-410.
Logan, G. D., Schachar, R. J., & Tannock, R. (1997). Impulsivity and inhibitory control. Psychological Science, 8(1), 60-64.
Martel, M. M., Nigg, J. T., Wong, M. M., Fitzgerald, H. E., Jester, J. M., Puttler, L. I., ... & Zucker, R. A. (2007). Childhood and adolescent resiliency, regulation, and executive functioning in relation to adolescent problems and competence in a high-risk sample.
Development and Psychopathology, 19(2), 541-563.
McMurran, M., Blair, M., & Egan, V. (2002). An investigation of the correlations between
aggression, impulsiveness, social problem ‐solving, and alcohol use. Aggressive Behavior, 28(6), 439-445.
Myaing, M. T., Garrison, M. M., Rivara, F. P., & Christakis, D. A. (2011). Differences between opt-in and actively recruited participants in a research study. Journal of
Nagin, D., & Tremblay, R. E. (1999). Trajectories of boys' physical aggression, opposition, and hyperactivity on the path to physically violent and nonviolent juvenile
delinquency. Child Development, 70(5), 1181-1196.
Piquero, A, Farrington, D. P., Welsh, B., Tremblay, R. E., & Jennings, W. J. (2009). Effects of early family/parent training programs on antisocial behavior and delinquency.
Journal of Experimental Criminology, 5(2), 83-120.
Polderman, N. (1998). Hechtingsstoornis, beginnen bij het begin. Tijdschrift voor
Orthopedagogiek, 10, 422-433.
Putnam, S. P. (2011). Stability and instability of childhood traits: Implications for personality development of animals. Developmental Psychobiology, 53(6), 510-520.
Putnam, S. P., Gartstein, M. A., & Rothbart, M. K. (2006). Measurement of fine-grained aspects of toddler temperament: The Early Childhood Behavior Questionnaire. Infant
Behavior and Development, 29(3), 386-401.
Ramírez, J. M., & Andreu, J. M. (2006). Aggression, and some related psychological
constructs (anger, hostility, and impulsivity): Some comments from a research project.
Neuroscience & Biobehavioral Reviews, 30(3), 276-291.
Rothbart, M. K., & Bates, J. E. (2006). Temperament. In N. Eisenberg, D. William, & R. M. Lerner (Eds.), Handbook of child psychology: Social, emotional, and personality
development (pp.105-176). Hoboken, NJ: Wiley.
Ruff, H. A., & Capozzoli, M. C. (2003). Development of attention and distractibility in the first 4 years of life. Developmental Psychology, 39(5),877-890.
Spinrad, T. L., Eisenberg, N., Gaertner, B., Popp, T., Smith, C. L., Kupfer, A., ... & Hofer, C. (2007). Relations of maternal socialization and toddlers' effortful control to children's adjustment and social competence. Developmental Psychology, 43(5), 1170-1186.
Taylor, R. (1990). Interpretation of the correlation coefficient: A basic review. Journal of
Diagnostic Medical Sonography, 6(1), 35-39.
Turner, P. J. (1991). Relations between attachment, gender, and behavior with peers in preschool. Child Development, 62(6), 1475-1488.
Vigil-Colet, A., Morales-Vives, F., & Tous, J. (2008). The relationships between functional and dysfunctional impulsivity and aggression across different samples. The Spanish
Journal of Psychology, 11(2), 480-487.
Zuckerman, M., & Kuhlman, D. M. (2000). Personality and risk-taking: Common biosocial factors. Journal of Personality, 68(6), 999-1029.
