Biomedical subjects

Walter Matthys

Publications and source records attributed to Walter Matthys.

13 recordsLinked to original sources

PubMed2007

Preventive effects of treatment of disruptive behavior disorder in middle childhood on substance use and delinquent behavior.

OBJECTIVE: Disruptive behavior disorder (DBD) is a well-known risk factor for substance abuse and delinquent behavior in adolescence. Therefore, the long-term preventive effects of treatment of DBD in middle childhood on beginning substance use and delinquency in early adolescence were investigated. METHOD: Children with DBD (8-13 years old) had been randomly assigned to manualized behavior therapy (Utrecht Coping Power Program; UCPP) or to care as usual (CU) in the Netherlands. Five years (2003-2005) after the start of treatment (1996-1999), substance use and delinquency were monitored in 61 of the initial 77 adolescents and compared with a matched healthy control group by means of self-report questionnaires. One-factor analyses of variance and Pearson's chi2 analyses were performed. RESULTS: Differences in substance use were revealed in favor of the UCPP, with more adolescents in the CU group smoking cigarettes in the last month (UCPP 17%, CU 42%; chi2 = 4.7; p < .03) and more adolescents in the CU group having ever used marijuana (UCPP 13%, CU 35%; chi2 = 4.0; p < .045). Moreover, in this respect, the UCPP fit in the range of the matched healthy control group. Both treatment groups were comparable to the matched healthy control group in delinquent behavior. CONCLUSIONS: Manualized behavior therapy for DBD in middle childhood seems to be more powerful than CU in reducing substance use in early adolescence. Both treatment conditions show a beneficial long-term preventive effect on delinquency.

Adolescent↗

PubMed2006

A parent questionnaire for distinguishing between reactive and proactive aggression in children.

BACKGROUND: Evidence suggests that reactive and proactive aggression can be distinguished on the basis of teacher-rating scales. In this article a newly developed parent-rated questionnaire that aims to distinguish between reactive and proactive aggression is evaluated with regard to its structure and validity. METHOD: In study 1, a confirmatory factor analysis was performed on the data of 442 children aged 6-12 years of a general population. Study 2 examined the relations between the two forms of aggression and hostile intentions, expected outcome of aggression, ADHD symptoms and callous-unemotional traits in a sample of 40 normal and 40 disruptive behaviour disordered boys aged 8-12 years. RESULTS: The confirmatory factor analysis showed that the two-factor model, unlike a singlefactor model, produced a reasonable fit to the data. The results of study 2 showed that the correlations between the different variables and reactive aggression differed from the correlations with proactive aggression in ways that were consistent with theoretical definitions and earlier findings. CONCLUSION: These results, in addition to those of earlier studies using teacher-rating scales, suggest that it is possible to make a valid distinction between reactive and proactive aggression using this newly developed parent-rated questionnaire.

Child↗

PubMed2005

Facial EMG responses to dynamic emotional facial expressions in boys with disruptive behavior disorders.

Based on the assumption that facial mimicry is a key factor in emotional empathy, and clinical observations that children with disruptive behavior disorders (DBD) are weak empathizers, the present study explored whether DBD boys are less facially responsive to facial expressions of emotions than normal controls. Facial electromyographic (EMG) activity in the zygomaticus major and corrugator supercilii muscle regions, and heart rate activity were studied in 22 clinically referred 8-12-year-old DBD boys and 22 age-matched normal controls during exposure to dynamic happy and angry expressions. Dispositional emotional empathy was assessed by a self-report questionnaire for children. The happy and angry facial expressions evoked distinct facial EMG response patterns, with increased zygomaticus muscle activity to happy expressions and increased corrugator muscle activity to angry expressions. The corrugator (but not the zygomaticus) muscle response pattern was less pronounced for DBD boys than the normal controls. Attending to the emotional expressions was associated with equivalent cardiac deceleration in both groups, reflecting a similar orienting/attention response. Lower empathy scores were obtained for DBD boys than for normal controls. In conclusion, facial mimicry responses to angry facial expressions were subnormal in DBD boys, which may be a sign of a deficient early component in the process of emotional empathy, and thus play a role in impaired empathic responding.

Affect↗

PubMed2005

Reactive and proactive aggression in children--a review of theory, findings and the relevance for child and adolescent psychiatry.

The clinical population of aggressive children diagnosed as having an oppositional defiant disorder (ODD) or a conduct disorder (CD) is heterogeneous, both with respect to behaviour and aetiology. Recently, the following distinction has been proposed that might further clarify this heterogeneity: reactive aggression is an aggressive response to a perceived threat or provocation, whereas proactive aggression is defined as behaviour that anticipates a reward. In this article we examine various aspects of this distinction. We will [1] examine the evidence that reactive and proactive aggression are distinct phenomena by discussing the theories underlying the distinction between the subtypes in humans and we briefly review evidence for a similar distinction in animals; [2] we critically review the literature on the measurement in children via questionnaires and behavioural observations; we then point out that the correlation observed between the subtypes is due to the fact that many children show both types of aggression; [3] we review the literature on specific characteristics of the subtypes giving attention to social information processing, peer status, biological correlates and developmental history, and demonstrate that there is some evidence to suggest that reactive and proactive aggression are distinct dimensions; [4] we discuss the relevance of the distinction between reactive and proactive aggression for child and adolescent psychiatry.

Adolescent↗

PubMed2005

Prediction of adolescent outcome in children with disruptive behaviour disorders--a study of neurobiological, psychological and family factors.

In this preliminary study we explored the predictive influence of various family, psychological, demographic, and neurobiological characteristics on the persistence of antisocial behaviour in adolescence. Existing data were combined with case-records in a sample of 47 disruptive behaviour disordered (DBD) children who had been treated in in-patient and/or day-treatment units when they were between seven to 12 years old. Parent-rated and self-rated externalizing problem scores and the presence of a DBD diagnosis served as the outcome measures in adolescence. We used linear regression analyses to examine the predictors of adolescent outcome. A lower basal skin conductance level (SCL) was repeatedly found to predict poor adolescent outcome, either when rated by parents or by participants themselves. In addition, comorbid attention-deficit hyperactivity disorder, one aspect of performance on the door-opening task, and a mother of low socioeconomic status also predicted that a child would have more antisocial problems in adolescence, depending on the type of outcome measure. Results of this study support the fearlessness theory, according to which low activity of the autonomous nervous system, as manifested by low SCL, is related to the effectiveness of socializing punishment and accordingly to poor socialization and adolescent outcome.

Adolescent↗

PubMed2005

Empathy in boys with disruptive behavior disorders.

BACKGROUND: The present study examined empathy in 8- to 12-year-old clinically referred boys with disruptive behavior disorders (DBD) (n=25) and age-matched normal controls (n=24). METHOD: Situational empathy was assessed by children's emotional and cognitive responses to six empathy-inducing vignettes (displaying sadness, anger or happiness). Dispositional affective empathy was measured by a self-report questionnaire for children. RESULTS: In line with predictions, results revealed deficits in dispositional and situational empathy among DBD boys, and inverse relationships between both empathy measures and parent-reports of aggressive/disruptive behavior among all children. The study also explored whether DBD boys are less responsive to just any emotion, or to specific emotions. Compared to normal controls, DBD boys responded less empathically to sadness and anger, but equally empathically to happiness. In addition, while DBD boys responded less empathically than the normal controls to each and every sadness vignette, they did not show equally low levels of empathic responses to all sadness vignettes. CONCLUSIONS: These findings suggest that situational factors may be involved in DBD boys' reduced responsiveness to another person's sadness.

Affect↗

PubMed2004

Response perseveration and sensitivity to reward and punishment in boys with oppositional defiant disorder.

Response perseveration is the tendency to continue a response set for reward despite punishment. In the present study, response perseveration and sensitivity to reward and punishment were assessed in boys with oppositional defiant disorder (ODD). The study also examined the relation between punishment sensitivity and autonomic arousal. Nineteen ODD boys (mean age 9.8 years) and 20 normal control boys (NC) (mean age 9.7 years) were administered the door-opening task. In this task, the subject chooses either to open the next door or to stop playing; the opening of doors is initially rewarded and then increasingly punished. ODD boys opened more doors than NC boys. Following punishment, ODD boys took less time than NC boys before opening the next door, but did not differ from NC boys in time after reward. Mean skin conductance level was lower in ODD boys than in NC boys. The correlation coefficient between time after punishment and skin conductance level was moderately positive in the total sample. These results suggest that response perseveration in ODD boys is related to low punishment sensitivity and that skin conductance level is a marker of punishment sensitivity.

Arousal↗

PubMed2004

Stress responsivity in children with externalizing behavior disorders.

Patterns of lower autonomic nervous system (ANS) and hypothalamic-pituitary-adrenal (HPA) axis activity have been found in children with oppositional defiant disorder (ODD). The aim of the present study was to investigate whether children with attention-deficit/hyperactivity disorder (ADHD) differ from ODD children with (OD/AD) or without comorbid ADHD in ANS and HPA axis activity under baseline and stressful conditions. The effects of stress on cortisol, heart rate (HR), and skin conductance level (SCL) were studied in 95 children (26 normal control [NC] children and 69 child psychiatric patients referred for externalizing behavior problems [15 ODD, 31 OD/AD, and 23 ADHD]). No baseline differences were found in cortisol between the four groups. However, the ODD and OD/AD groups showed a significantly weaker cortisol response to stress compared to the ADHD and NC groups; the ADHD group had a similar cortisol response as the NC group. Within the ODD group this pattern of low cortisol responsivity was most clearly present in the more severely affected inpatients. With respect to HR, the ODD group had a significantly lower HR during baseline and stressful conditions. The higher HR levels in the OD/AD and ADHD groups were likely to be caused by methylphenidate. The externalizing groups had significantly lower SCL levels, and no differences were found between these groups. It was concluded that differences in cortisol responsivity during stress exposure are important in distinguishing within a group of children with externalizing behavior between those with ODD and ADHD.

Arousal↗

PubMed2004

Cortisol and treatment effect in children with disruptive behavior disorders: a preliminary study.

OBJECTIVE: Basal cortisol and cortisol stress responsivity are valuable biological characteristics of children with disruptive behavior disorder (DBD). In this study, the predictive value of cortisol to outcome of intervention was investigated. METHOD: Basal cortisol levels and cortisol levels under stress were studied in 22 children with DBD before the start of a psychotherapeutic treatment. The disruptive behavior of the child was assessed before treatment and after cessation (9 months later). RESULTS: Children with DBD with relatively high and low basal cortisol levels differed in the severity of problem behavior at pretreatment, with the low basal cortisol group having more severe problems. During stress, children with DBD showed either increasing or decreasing cortisol values. Although these cortisol responsivity groups were similar in the severity of behavioral problems at pretreatment, the behavioral problems of the group with high cortisol stress responsivity were significantly lower after the intervention than the behavioral problems of the group with low cortisol stress responsivity. CONCLUSIONS: In children with DBD, the basal cortisol level was related to the severity of behavioral problems at pretreatment but not to the severity of behavioral problems after treatment. The cortisol response pattern during stress was related to treatment outcome.

Adolescent↗

PubMed2004

Executive functioning in children: a comparison of hospitalised ODD and ODD/ADHD children and normal controls.

BACKGROUND: Deficits in executive functioning are supposed to have a predisposing influence on impulsive or aggressive behaviour. We tested the hypothesis that oppositional-defiant disorder (ODD) children with or without attention deficit hyperactivity disorder (ADHD) have problems in executive functioning. METHOD: Seventy-seven 7- to 12-year-old children (15 ODD, 26 ODD/ADHD, and 36 normal controls), all with normal IQ, completed 7 neuropsychological measures of executive functioning, assessing the abilities of set shifting, planning, working memory, inhibition/attention, and impulsivity. Some of these tasks involved the possibility of monetary rewards with a view to testing the prediction of a specific motivational inhibitory deficit. RESULTS: We found no evidence of deficits in working memory, planning, inhibition, or impulsivity. However, the ODD/ADHD group was worse than the normal control (NC) group in set shifting, and both the ODD and ODD/ADHD groups performed worse on a response perseveration task. Moreover, on the basis of one variable derived from a motivational inhibition task, 77% of the children could be correctly classified as ODD or NC. CONCLUSIONS: The findings do not support the hypothesis that ODD and ODD/ADHD children have a deficit in executive inhibitory control; rather, they emphasise that they have problems in regulating their behaviour under motivational inhibitory conditions.

Attention↗

PubMed2004

Evidence of fearlessness in behaviourally disordered children: a study on startle reflex modulation.

BACKGROUND: Patterns of low heart rate, skin conductance and cortisol seem to characterise children with disruptive behaviour disorder (DBD). Until now, the startle paradigm has not been used in DBD children. We investigated whether DBD children, like adult psychopaths, process emotional stimuli in an abnormal way. METHOD: Twenty-one DBD and 33 normal control children viewed a series of 27 positive, neutral and negative slides. Startle probes were presented unpredictably during slide presentations and eye blink reflexes were measured. RESULTS: DBD and control children showed a similar linear relationship between slide valence and startle magnitude, but the startle-elicited blinks of the DBD children were significantly lower for all categories of slides. Moreover, the more delinquent the DBD children were, the lower their startle responses during unpleasant states. CONCLUSIONS: The results suggest a deficit in neurophysiological fear modulation. The implications of the findings for the fearlessness theory of antisocial behaviour are discussed.

Antisocial Personality Disorder↗

PubMed2002

Serotonergic functioning in children with oppositional defiant disorder: a sumatriptan challenge study.

BACKGROUND: Several studies support the notion that disturbances in the central serotonergic function are related to impulsive aggression. There is recent evidence from studies on 5-HT(1B) knock-out mice that this specific receptor is involved in impulsive aggressive behavior. The aim of the present study was to investigate 5-HT(1B/1D) receptor functioning in normal intelligent hospitalized children with oppositional defiant disorder (ODD). METHODS: The growth hormone (GH) response to a challenge with the 5-HT(1B/1D) agonist sumatriptan was examined in 20 children with an ODD, of whom 13 had an attention-deficit/hyperactivity disorder comorbidity, and 15 normal control subjects (NC). Blood samples for growth hormone were collected repeatedly between 8:30 and 12:00 AM. Sumatriptan was administered at 10 AM. The effect of stress due to this procedure was assessed by measuring salivary cortisol. RESULTS: The GH response was significantly stronger in the children with ODD. After sumatriptan injection NC children showed a significant increase in cortisol; no such pattern was present in the ODD group. CONCLUSIONS: The results suggest that the postsynaptic 5-HT(1B/1D) receptor is functionally more sensitive in children with ODD.

Aggression↗

PubMed2002

Preference for aggressive and sexual stimuli in children with disruptive behavior disorder and normal controls.

Children with disruptive behavior disorders (DBD) have poor social skills and show aggressive interaction patterns. There is evidence from prospective studies of an association between early physical abuse, later social information-processing patterns, and aggressive behavior. A pattern of hypervigilance to hostile cues has been found in DBD children, but very few studies have investigated encoding or perceptual preference for specific classes of stimuli. Some DBD children have a suspected history of sexual abuse and a few have themselves been sexually offensive. Our belief that the sexuality of DBD children should be investigated raised the issue of how to go about doing this. A procedure was developed in which we measured the relative preference for sexual and aggressive stimuli in comparison to other stimulus categories, and the data of DBD children were compared with those of normal controls. It was found that DBD children preferred viewing sexual slides and had a lower preference for nonaggressive slides. Furthermore, boys in general preferred viewing aggressive slides, did so for longer, and chose them earlier, whereas the more aggressive DBD children distinguished themselves in selecting aggressive stimuli earlier. The implications of these findings were discussed and it was concluded that sexuality is clearly an important topic to address in aggressive children in general and not only in the abused ones.

Aggression↗