1. Method Introduction Aims of the study Results georgiap@ucy.ac.cy
AFFECTIVE STARTLE MODULATION AS RELATED TO SCHOOL-BASED AGGRESSION
Chrysostomos Lazarou & Georgia Panayiotou
Department of Psychology and Center for Applied Neuroscience, University Of Cyprus, Nicosia, Cyprus
Method
Introduction
Sample:
Participants were drawn from an initial sample of N=907 Greek-Cypriot students (grade 5-8 ) who were screened for school bullying/victimization involvement. Of the initial sample, 95 students were selected as either Bullies, Victims or Bully-Victims (Clinical Sample) and 764 as Uninvolved. From those, a total of 40 children participated in the second phase of the study (experiment) as Bullies (N=9), Victims (N=8), Bully-Victims (N=11) or Uninvolved (N=12). Categorization was based on BVQ cut-offs as follows: The Bully group scored 1 Standard Deviation above the mean of the respective distribution of scores and below the mean of the victimization distribution of scores; The Victims group scored 1 Standard Deviation above the mean of the respective distribution of scores and below the mean of the bullying distribution of scores ; The Bully-Victim group scored 1 Standard Deviation above the mean on both dimensions and the Uninvolved group scored 1 Standard Deviation below the mean on both dimensions.
A student is said to be bullied when he/she is exposed, repeatedly and over time, to negative actions (e.g. hitting, kicking, pushing, taking of personal belongings, threatening, isolating, and gossiping) on the part of one or more students (Olweus, 1993; Karatzias, Power & Swanson, 2002; Smith & Sharp, 1994). Bullying derives from a need to exert power over others and a desire to dominate them. School bullies run an increased risk of engaging in aggressive/violent behavior later in life (Ttofi, Farrington & Lösel, 2012), criminality and alcohol abuse. In fact, bullying has been linked to high levels of psychopathic features (i.e. callous unemotional traits ; Fantis et al., 2008), conduct problems (Kokkinos & Panayiotou, 2004) as well as proactive and reactive aggression (Salmivalli & Nieminen, 2002). Compared to unreliable and potentially biased self-report measures of behavior, attitudes and personality, psychophysiological measurements offer a more objective approach to studying individual differences and basic psychological processes. Examining the psychophysiological mechanisms underlining bullying behavior may help in the early identification of children and adolescents at risk, interventions and in theoretically linking this phenomenon to what is already known about aggressive and antisocial behavior.
Research with adult psychopaths-especially those who are high on “factor 1” psychopathy traits such as callousness and low empathy (Patrick et al., 1993) - and conduct disordered youths (Fairchild et al., 2008) has shown a failure to exhibit increased startle reaction (startle potentiation) to negative situations. This, has been suggested, may be due to a distinguishing feature of psychopaths, that of fearlessness.
These effects have rarely been examined in children or in relation to the phenomenon of school bullying and relevant affective startle modulation research with children and youth is very limited. In particular, no prior similar research using the tone-cued affective imagery paradigm has been conducted with this population to our knowledge.
Measures:
The Revised Bullying and Victimization Questionnaire (BVQ; Olweus, 1996); is a 28-item, five-point, Likert-type scale, self-report measure, assessing aspects of bullying and victimization (having been called bad names, having belongings taken without permission, having lies told about them, having nasty tricks played on them, having been threatened or blackmailed, having been hit or beaten up and having been systematically excluded from groups).
The Reactive-Proactive Aggression Questionnaire (Raine et al., 2006), is a 23-item scale used to measure proactive (e.g. “Had fights with others to show who was on top”) and reactive aggression (e.g. “Got angry when others threatened you”). The items reflect physical or verbal aggression of both proactive and reactive types of aggression.
The Inventory of Callous-Unemotional Traits (ICU; Frick, 2004); is a 24-item self-report questionnaire designed to assess callous and unemotional traits in youth. Previous factor analytic studies identified three factors: Callousness (e.g., “The feelings of others are unimportant to me”), Unemotional (e.g., “I hide my feelings from others”), and Uncaring (e.g., “I try not to hurt others’ feelings”).
The Child Behavior Checklist (Achenbach), was administered to parents of the children who participated in the experimental phase.
Physiological data were collected using the BIOPAC MP1500 system and Acknowledge software using standard electrode placement. Subjective rating of emotional dimensions (valence, arousal, dominance, vividness of mental scene and emotional reaction to the scene) were completed by the participants following each block of imagery scripts.
Design:
Participants took part in a tone-cued imagery paradigm experiment during which they imagined (for 8 second periods) 12 age-appropriate scripts (3 for each emotion: Fear, Anger, Joy and Pleasant Relaxation) that had previously been rated by a normative sample on valence, arousal and dominance. Imagery trials were cued by high or low pitch tones and were separated by relaxation periods lasting s. Medium pitch tones cued relaxation. At the end of each block, participants completed subjective ratings.
Aims of the study
This study aims to investigate how children involved in school bullying and victimization in various roles i.e. bullies, victims, bully-victims and uninvolved, respond physiologically to various affective situations, including fear and anger/provocation, that represent common everyday scenes: It is hypothesized that aggressive, compared to non-aggressive, children will exhibit lower reactivity to fear, in accord with the fearlessness hypothesis.
The study also aims to investigate the association between bullying behaviors and related characteristics (proactive and reactive aggression and callous-unemotional traits).
Results
Table 1. shows Means and Standard Deviations of responses on the Fear Startle Index* and various individual differences characteristics of participants, separated into groups on the basis of their scores on the BVQ.
* (The Fear Startle Index was calculated as Fear startle response minus Pleasant Relaxation response)
Samples of imagery scripts
Anger
• While you are getting ready to sit in your seat, a child suddenly pulls your chair so that you fall on the floor and the whole class starts laughing with you.
Fear
• Alone in the alley, your heart starts beating fast, your stomach tightens while a group of older children are surrounding you laughing and threatening
Joy
• You jump with joy as your dad, is giving you your Christmas gift, a brand new mobile phone of the latest technology!
Pleasant Relaxation
• You had just finished your homework and you are relaxing on your living room sofa, watching your favourite TV program.
Table 2 shows zero order correlations among individual difference characteristics on the experimental sample. Bullying was related to both proactive and reactive aggressive behavior, callous characteristics, and high behavioral activation. Victimization scores were positively related to high behavioral inhibition and negatively to uncaring characteristics.
A linear regression analysis was conducted with Fear Startle Index (T-score) as the dependent variable and bullying, victimization and bullying x victimization interaction scores as the predictor variables.
High bullying was negatively associated with Fear Startle Index for participants with high victimization (i.e. bully-victims). High victimization was marginally positively associated with Fear Startle Index for participants with low bullying (i.e. victims).
Note. Fear Startle Index = Fear startle magnitude minus Pleasant Relaxation magnitude
Bullying and victimization behaviors and their interaction did not significantly predict startle responses to anger or joyful scenes.
Girls responded with higher mean corrugator response during Fear imagery than boys. However, no significant effects of bullying and victimization were observed and no interactions with gender, in any emotion categories.
No significant effects of bullying and victimization, gender or age were observed for zygomaticus major activity during pleasant imagery.
Arousal Ratings Anger
Self-report ratings after each imagery block indicated that victims reported significantly greater arousal during anger (provocation) imagery than bullies while both victims and bully-victims reported more negative valence during Fear imagery than other groups, with bullies-only reporting the least negative affect in this emotional condition. Other rating differences were not significant.
The present study examined the effects on startle reactivity, facial EMG and emotional ratings of involvement in school aggression, specifically among children selected as Bullies, Victims, Bully-Victims and Uninvolved. Based on previous findings with adults, and evidence that bullying behavior is associated with some core features of antisocial/psychopathic traits that have been found to predict low startle potentiation by negative affect (e.g. Patrick et al., 1994), we anticipated that aggression (i.e. bullying, bullying-victimization interaction) would be associated with the least startle potentiation. In particular, it was the bully-victims that showed the least startle potentiation during fear imagery. The bully-victim group has been characterized as having the most psychological difficulties before (Kokkinos & Panayiotou, 2004; Brunstein et.al., 2007) and current findings show they have high levels of callous-unemotional characteristics as well. Victimization was associated with increased startle potentiation by fear, potentially due to links between this behavior, high anxiety and high behavioral inhibition. Indeed, victims reported the most arousal during anger imagery (which included scenarios probably reminiscent of their victimization experiences) and the most negative affect during fear, indicating that physiological effects may be linked to their greater negative affectivity. Startle potentiation was the only response that these traits appeared to affect. No effects of these behaviors on facial muscle reactivity to various emotions were obtained. This finding is in line with prior findings showing that deficits in emotion processing among individuals high in psychopathic/antisocial characteristics are circumscribed to the defensive system, (i.e. fearlessness; e.g. Lykken, 1995) specifically as indicated by the fear potentiated startle.
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