Attention-deficit/hyperactivity disorder (ADHD), major depressive disorder (MDD), and generalized anxiety disorder (GAD) are often co-morbid, and their prevalence is increased in the student...Show moreAttention-deficit/hyperactivity disorder (ADHD), major depressive disorder (MDD), and generalized anxiety disorder (GAD) are often co-morbid, and their prevalence is increased in the student population. The dynamics between self-regulation problems and ADHD, MDD, and GAD may reveal insights into the co-occurrence of the three disorders. The present study focused on psychological factors that support or threaten successful self-regulation. Using cross-sectional data, a network analysis was performed based on a sample of 902 students currently enrolled in higher education programs in the Netherlands. The analysis featured 17 commonly studied risk and protective factors associated with all three disorders. The network showed that irritability and impairments in daily functioning were shared problems between ADHD, MDD, and GAD. The network further suggested that impaired cognition and a propensity for procrastination are shared features of ADHD and MDD. ADHD and GAD did not share a direct relationship, diverging from previous assumptions. The findings highlight that the relationship between the disorders may depend on shared vulnerabilities and outcomes that act as bridges in the network. The study illustrates that psychological constructs need to be more clearly defined to move forward when researching co-morbidity beyond the level of symptoms.Show less
This study aims to investigate relative age within primary school grades as a potential influential factor of perceived ADHD symptoms. It examines whether relatively younger pupils show more ADHD...Show moreThis study aims to investigate relative age within primary school grades as a potential influential factor of perceived ADHD symptoms. It examines whether relatively younger pupils show more ADHD symptoms than their classmates. The study is of cross-sectional design, using data of primary school children throughout the Netherlands. Participating children are in the age range of four to twelve years old, N = 168. To measure ADHD symptoms, the SNAP-IV (18) has been filled out by parents of the participating children. Relative age serves as the main predictor of this study. Simple linear regressions have been run on relative age (predictor) and ADHD symptoms (dependent). Analyses showed that relative age is no predictor of ADHD symptoms, implying that relative age is no influential factor in perceived ADHD symptoms. However, data screening pointed out that the sample of the current study might not be representative for the general population. Furthermore, the current research design worked with parental observations of ADHD symptoms, and not official ADHD diagnoses. Whether a child has had an ADHD diagnosis was unknown during this study. Incorporating this information in future research could potentially lead to a better understanding of the topic. All in all, the results of this study must be interpreted with care and future research is needed to (dis)prove the relation between relative age and ADHD symptoms.Show less
The behavioural overlap observed between developmental dyslexia and other neurodevelopmental disorders (NDDs) such as ADHD and ASD is an ongoing topic of research. The complexity of these...Show moreThe behavioural overlap observed between developmental dyslexia and other neurodevelopmental disorders (NDDs) such as ADHD and ASD is an ongoing topic of research. The complexity of these conditions, coupled with the overlap in behavioural characteristics, contributes to the challenge of accurately diagnosing dyslexia. Consequently, there is a prevalent tendency for learning disabilities such as dyslexia to be underdiagnosed. This study aims to examine whether there are specific cognitive impairments attributable to dyslexia, that are not observed in NDDs in general. The answer to this question was examined by comparing the cognitive profile of children diagnosed with a NDD and dyslexia to children diagnosed with a NDD but not dyslexia. The WISC-V was administered to 57 children aged between 7 and 16 years. The findings of this study showed no differences in the frequency of a deviant IQ profile between children with a NDD, with or without (suspected) dyslexia. In addition, the results showed no stronger relative weakness on the indexes of working memory, verbal comprehension, and processing speed for children with dyslexia compared to children with a NDD but not dyslexia. To conclude, the current study found no evidence for specific cognitive impairments attributable to dyslexia. Due to the small sample size in this study, further conclusions cannot be drawn from these results. Since the obtained results contradict the results of previous studies, a follow-up study to gain more knowledge about the cognitive profile of dyslexia in co-occurrence with other NDDs is advised.Show less
ADHD is a well-known neurodevelopmental disorder that extends from childhood into adulthood for many individuals. Symptoms of ADHD can be categorized into three subtypes: hyperactivity, inattention...Show moreADHD is a well-known neurodevelopmental disorder that extends from childhood into adulthood for many individuals. Symptoms of ADHD can be categorized into three subtypes: hyperactivity, inattention, and impulsivity. Males typically exhibit more external symptoms, while females tend to display more internal symptoms, such as inattention. However, both genders are diagnosed using the same criteria, resulting in a higher rate of ADHD diagnosis among males. Our understanding of gender differences in the presentation of symptoms, particularly inattention, remains limited. However, exploring the concept of cognitive flexibility becomes relevant when examining inattention, as it encompasses the ability to adapt and shift one's thinking and behavior in response to changing circumstances or tasks. By considering cognitive flexibility, we can gain valuable insights into how inattention may impact individuals with ADHD and potentially contribute to gender differences in symptomatology. A total of 100 participants completed a computer-based task that assessed task-switching performance which measured reaction time and accuracy for switch cost and incongruent cost. A Multiple Regression Analysis was conducted to examine the relationships between gender, inattention, and task-switching performance. The results of the study did not yield statistically significant findings, indicating no substantial gender differences in task-switching performance and its association with inattention in individuals with ADHD. A few limitations of the study include a relatively small sample size and the possibility that females filled in the self- report questionnaire based on their presumption that they are less likely to have characteristics of ADHD. Future studies should focus on larger and more diverse samples to enhance the generalizability of the findings.Show less
This retrospective cohort study aimed to investigate the influence of stress on atypical symptom amelioration to first-choice psychostimulant medication in individuals with attention deficit...Show moreThis retrospective cohort study aimed to investigate the influence of stress on atypical symptom amelioration to first-choice psychostimulant medication in individuals with attention deficit hyperactivity disorder (ADHD). Understanding the impact of stress on the effectiveness of psychostimulant medications is crucial, given the high prevalence of stress-related psychiatric comorbidity in ADHD and the potential stress effects on psychostimulant effectivity. It was hypothesized that cardiovascular stress and stress-related psychiatric comorbidity are related to atypical symptom amelioration and that these two characteristics are interrelated. Additionally, the effect of medication and time will be explored. A unique subset from the SOPHISTICATE cohort was analysed, comprising of 460 patients diagnosed with ADHD who exhibited atypical treatment response following first-choice medication registration and were switched to a second-choice medication within 3 weeks. The adult version of the Quantified Behavioral Test (QbTest), a computerized tool that quantifies the core symptoms of ADHD was used to determine baseline symptom severity and treatment response, i.e. QbActivity (QbAct); QbImpulsivity (QbImp); and QbInattention (QbIna). Patients were divided into groups based on stresscharacteristics, and linear mixed models were employed to examine the impact of stresscharacteristics, first-choice medication and time on symptom amelioration (i.e. QbTest score after first- or second-choice medication – QbTest score at baseline; ∆). The results reveal that stress-characteristics were not related to atypical symptom amelioration after first-choice medication. However, patients with stress related psychiatric comorbidity show more inattentive symptom amelioration after second-choice medication registration β=.21, SE=.10, 95% CI [.02, .41], p=.031. Importantly, the effect of time was significant for all three symptom domainssuggesting a role of time to enable a typical response, i.e. ∆QbAct (F(1,462) = 387.818, p < .001), ∆QbImp (F(1, 462) = 235.224, p < .001) and on ∆QbIna (F(1, 463) = 319.655, p = .242). Additionally it was found that baseline symptom severity confounds the medication effect for ∆QbImp and for ∆QbAct. In conclusion, the results indicate that stress characteristics nor medication is related to an atypical response pattern to first-choice medication. The current study did reveal an important role of time to enable a ‘typical’ response. Limitations of the study included the lack of a reference group, the possibility of random effects, and quality of the cardiovascular data. In conclusion, while the impact of stress on treatment response could not be definitively determined based on the available data, future research should explore the complex interplay between stress, psychiatric comorbidity, and medication types to optimize treatment strategies and improve outcomes for patientsShow less
This study aimed to expand on previous research regarding the stability-flexibility dilemma and the adjustment of neural gain. Specifically, it was investigated if people lower their neural gain in...Show moreThis study aimed to expand on previous research regarding the stability-flexibility dilemma and the adjustment of neural gain. Specifically, it was investigated if people lower their neural gain in response to a short CSI. Previous research showed that people can adjust their neural gain based on the demand for flexibility. Specifically, lower neural gain would facilitate flexibility, but at the cost of stability. In addition, the relation between ADHD and neural gain was studied. Participants were asked to take part in a task-switching experiment in which they had to classify digits either based on parity or magnitude. Herein, the CSI duration was manipulated. Afterwards, a computational model estimated the neural gain values per condition. Participants were also asked to fill out an ADHD questionnaire. The final number of participants was 60 aged between 18 and 30. The results showed that the participants had higher switch costs and higher incongruency costs when the time to prepare was short. In addition, it was found that the participants lowered their neural gain in response to a short preparation time. Contradictory to our expectations, no relation was found between ADHD and neural gain adjustment. Together, the behavioral results and the neural gain analysis show that while lowering gain facilitates switching and thus flexibility, it also reduces focus and thus stability. For future research, it is suggested to replicate the study in a controlled environment and specifically regarding ADHD to either use a clinical sample or additional assessment tools, such as eye-tracking.Show less
Recent research by Sharon et al. (2020) indicated an activating effect of transcutaneous auricular vagus nerve stimulation (taVNS) on the locus coreleus noradrenergic (LC-NA) system. Given the...Show moreRecent research by Sharon et al. (2020) indicated an activating effect of transcutaneous auricular vagus nerve stimulation (taVNS) on the locus coreleus noradrenergic (LC-NA) system. Given the mixed findings of previous research, we replicated this study to validate and extend their results. Twenty-one subjects participated in a repeated measures design using the same no-task paradigm as Sharon et al. (2020). Additionally, we extended the analysis to explore indicators of LC-NA activity in the EEG time domain. We compared EEG activity between sham (earlobe) and stimulation (cymba conchae) conditions. Our analysis found significantly less alpha activity during taVNS compared to sham stimulation. This confirms the finding of Sharon et al. (2020) - taVNS attenuates alpha oscillations. However, we found no differences in ERPs between conditions. This was likely due to methodological limitations that make the design inappropriate for ERP research. Our results support an effect of taVNS on phasic LC-NA activity, but the effect on tonic LC-NA remains unknown. This is discussed from the perspective of using taVNS as an intervention for disorders such as ADHD. Based on our exploratory analysis and literature findings, recommendations are made for future research.Show less
Adolescence is a time when there are lots of changes going on for most young people. Especially friends and social connections are important in this period and mostly the quality of friendship....Show moreAdolescence is a time when there are lots of changes going on for most young people. Especially friends and social connections are important in this period and mostly the quality of friendship. During adolescence, young people can also experience (symptoms of) behavior issues. These issues are for example behavior disorders and the disorder ADHD. The goal of this study was to get an insight of the way in which symptoms of ADHD and behavior disorders can influence the degree of friendship quality during early adolescence. Also, there has been looked at the interaction effect between symptoms of ADHD and behavior disorders on friendship quality. For this research, 119 participants between twelve and sixteen years old have filled in online questionnaires, the ADHD self-report questionnaire, the SDQ for behavior issues and the FSQ and NRI for friendship quality. There’s been a multiple hierarchical regression analysis performed in which there was not a significant model and main effect found of symptoms of ADHD and behavior disorders on friendship quality. There was also not a significant effect in the interaction effect of symptoms of ADHD and behavior disorders on friendship quality. This study shows that the results are not aligned with the hypotheses and earlier research and it is of importance that further research takes a different age range into account of adolescents (14-17) in regard to gender and using extended questionnaires in which other context will be integrated as well.Show less
Reward processing abnormalities have been observed in individuals with attention deficit/hyperactivity disorder (ADHD) in both behavioral and neuroimaging studies. Models of reinforcement learning...Show moreReward processing abnormalities have been observed in individuals with attention deficit/hyperactivity disorder (ADHD) in both behavioral and neuroimaging studies. Models of reinforcement learning in healthy individuals have laid the foundation for neurobiological theories addressing reward processing in ADHD. In healthy individuals, dopamine responses in ventral striatum (VS) gradually shift from actual rewards received (prediction error [PE]), toward cues which reliably predict such rewards (reward expectancy [RE]). Drawing on these observations, two theories posit that either low striatal dopamine (dynamic developmental theory) or failed signal shifts per se (dopamine transfer deficit theory) are behind reward-processing deficits in individuals with ADHD. However, the predicted signal abnormalities have not been examined directly. Forty-two participants with ADHD and 56 typically developing (TD) controls participated in a functional magnetic resonance imaging (fMRI) reward paradigm examining whole-task and temporal-change measures of PE and RE. Results showed that, contrary to theoretical predictions, the groups did not differ in either an overall measure of RE, or a composite index of PE-RE signal shifts. Furthermore, while overall PE activity was higher in the ADHD group (partly supporting the dopamine transfer deficit theory, which allows for high PE), observed decreases over time were similar between the groups (which was unexpected). Exploratory dimensional analyses showed that while a positive linear relationship between hyperactive/impulsive symptoms and RE was present in the full group, a quadratic (inverse U-shape) model better explained this relation in a sub-sample with currently-diagnosed ADHD, possibly supporting a model of downregulation due to higher symptoms. Finally, there were no significant associations between the index of temporal signal shifts and symptoms, or between overall PE and symptoms. In sum, results do not support the dynamic developmental theory, and only partially support the dopamine transfer deficit theory. Additionally, results suggest that overall signals, rather than dynamic changes, are better able to differentiate ADHD whether at the group level (PE) or at the individual level (RE). Increased PE in ADHD also suggests that immediate rewards (versus delayed reward anticipation cues) may be a useful strategy for interventions.Show less
Eerder onderzoek heeft aangetoond dat slaapproblemen veroorzaakt kunnen worden door een inadequate slaaphygiëne, een term die alle routines en gedragingen omtrent slaap omvat. Het doel van dit...Show moreEerder onderzoek heeft aangetoond dat slaapproblemen veroorzaakt kunnen worden door een inadequate slaaphygiëne, een term die alle routines en gedragingen omtrent slaap omvat. Het doel van dit onderzoek was om meer inzicht te verkrijgen in de slaaphygiënische achtergrond van slaapproblemen bij kinderen met ADHD of een autisme spectrumstoornis (ASS). De relatie tussen slaaphygiëne en slaapkenmerken is onderzocht bij 346 jongens en meisjes tussen de zes en twaalf jaar met ADHD (zonder ASS) (N = 51), ASS (zonder ADHD) (N = 58) en met een normaal verlopende ontwikkeling (N = 237). Dit is gedaan aan de hand van de slaaphygiëne balans voor kinderen (SHBK) en de slaapverstoringsschaal voor kinderen (SDSC). De data is geanalyseerd door middel van correlatieanalyses, ANOVA en Kruskal-Wallis toets. De resultaten van dit onderzoek wezen erop dat kinderen met ADHD en ASS een significant slechtere slaaphygiëne hadden in vergelijking met kinderen met een normale ontwikkeling. Een slechtere slaaphygiëne hing samen met meer slaapproblemen, een langere inslaaptijd, een kortere slaapduur en een langere latentietijd, zowel op vrije dagen als op schooldagen. Daarnaast zijn er specifieke slaaphygiënische indicatoren gevonden die afwijkend waren voor kinderen met ADHD en ASS. Dit onderzoek vergroot de kennis over de relatie tussen slaaphygiëne en slaapproblemen bij kinderpsychiatrische stoornissen en draagt zo bij aan een empirische ondersteuning van slaapinterventies. Verondersteld wordt dat het verbeteren van de slaapkwaliteit kan worden aangepakt door onder andere in te spelen op deze specifieke slaaphygiënische indicatoren.Show less
The importance of this research is to enlarge the understanding of the cohesion between emotional regulation and externalizing behavioural problems and insights into specific treatments and...Show moreThe importance of this research is to enlarge the understanding of the cohesion between emotional regulation and externalizing behavioural problems and insights into specific treatments and counseling which professionals could use with children who have ASD and ADHD. Objective: The objective of this research is gaining an insight into the relationship between emotional regulation and externalizing behavioural problems in children with ASD and ADHD in ages from 4 to 18 years. Method: The research subjects are children aged between 4 and 18 years with and without ASD and ADHD. They are children from special and regular education and those who receive guidance at a healthcare facility. The children’s parents have completed the Social Emotional Questionnaire (SEV) and the Emotional Intelligence Quotient (EIQ). Results: The study comprised 195 children of which 108 boys and 87 girls, of which 115 children who did not have a disorder, 33 children with ASD and 47 children with ADHD. Children with ASD and ADHD display more externalizing behavioural problems than children without a disorder and children with ADHD display more externalizing behavioural problems than children with ASD. Children with ASD and ADHD also display deficiencies in terms of regulating emotions compared to children without a disorder. The type of developmental disorder makes no difference. Conclusions: Children with ASD have typically problems in managing emotions and this is linked to age. Children with ADHD have typically problems in regulating emotions. In addition children with ADHD display externalizing behavioural problems. Children without any disorders display a good emotional regulation. For a part of these children this goes hand in hand with delinquent behaviour. This study has dealt with externalizing problem behavior as a whole. There is a possibility that there are differences between antisocial and aggressive behaviour. Future research can focus on this.Show less
In deze studie is onderzocht wat de invloed van inhibitie vermogen en ADHD op het gebruik van alcohol is. Een gebrekkig inhibitie vermogen is een kenmerk van ADHD (Nigg, 1999). Uit onderzoeken...Show moreIn deze studie is onderzocht wat de invloed van inhibitie vermogen en ADHD op het gebruik van alcohol is. Een gebrekkig inhibitie vermogen is een kenmerk van ADHD (Nigg, 1999). Uit onderzoeken blijkt dat een verslechterd inhibitie vermogen de kans op het gebruik van alcohol vergroot (Fernie et al., 2013) Veel onderzoeken tonen ook aan dat ADHD meer alcohol gebruik kan veroorzaken (Ohlmeier et al., 2008), maar hierover bestaat geen consensus. Het aantal participanten in deze studie was 1049. Dit leeftijd lag tussen de 11 en de 30 jaar (N = 21.38, SD = 3.55). Van de participanten was 43,4% man en 56,5% vrouw. Alle participanten hebben vragenlijsten ingevuld. Voor deze zijn de inhibitie schaal uit de Behavior Rating Inventory of Executive Function (BRIEF), de ADHD schalen uit de Adult Self Report (ASR) en de Youth Self Report (YSR) en gegevens over het alcoholgebruik uit de middelenlijst gebruikt. Voor het verkrijgen van de resultaten zijn correlaties en multipele regressie analyses uitgevoerd. Uit de correlaties bleek inhibitie vermogen significant te correleren met zowel ADHD (r = 0.673, p < 0.001) als alcohol gebruik ( r = 0.092, p = 0.005). Alcohol gebruik bleek niet significant gerelateerd aan ADHD in zowel de groep onder de 18 (r = 0.027, p = 0.81) als de groep boven de 18 (r = 0.019, p = 0.58). Inhibitie vermogen bleek wel invloed te hebben op alcohol gebruik en ADHD niet. Wanneer er gecontroleerd werd voor ADHD bleef de relatie tussen inhibitie vermogen en alcoholgebruik significant, wat aangeeft dat ADHD-kenmerken niet alle invloed van een gebrekkig inhibitievermogen verklaren. Inhibitie vermogen bleek een groter effect te hebben op alcohol gebruik bij de groep onder de 18 jaar.Show less
In deze studie is onderzocht of er een verschil is in de mate van algemene angst tussen kinderen met en zonder een autisme spectrum stoornis of een aandachtstekortstoornis met hyperactiviteit....Show moreIn deze studie is onderzocht of er een verschil is in de mate van algemene angst tussen kinderen met en zonder een autisme spectrum stoornis of een aandachtstekortstoornis met hyperactiviteit. Hierbij is onderzocht of de intrapersoonlijke vaardigheden en het emotionele intelligentieniveau van kinderen mediërende factoren zijn. De steekproef bestaat uit 340 Nederlandse kinderen met leeftijden variërend tussen de 4 en 18 jaar. Hun ouders werden gevraagd drie vragenlijsten in te vullen: de vragenlijst Emotioneel Intelligentie Quotiënt (EIQ) om het emotionele intelligentieniveau te meten, de Sociaal Emotionele Vragenlijst (SEV) waarmee de mate van angst en het wel of niet hebben van ASS of ADHD gemeten werd, en de Vragenlijst Psychosociale Vaardigheden (VPV) om de kwaliteit van de intrapersoonlijke vaardigheden te meten. In dit onderzoek is gevonden dat kinderen met ASS een hoger niveau van algemene angst hebben dan kinderen met ADHD. Kinderen met ADHD hebben vervolgens een hoger niveau van algemene angst dan kinderen zonder deze ontwikkelingsstoornissen. Tevens is gebleken dat kinderen met ASS of ADHD minder goede intrapersoonlijke vaardigheden en minder hoge emotionele intelligentieniveaus hebben dan kinderen zonder deze ontwikkelingsstoornissen. Met betrekking tot de emotionele intelligentie is daarnaast gevonden dat kinderen met ASS lagere niveaus hebben dan kinderen met ADHD. Bij kinderen met ASS blijken de intrapersoonlijke vaardigheden en vooral het emotionele intelligentieniveau mediërende factoren: de kwaliteit hiervan is van invloed op de mate van algemene angst. Bij kinderen met ADHD is dit vrijwel niet het geval, waardoor de intrapersoonlijke vaardigheden en het emotionele intelligentieniveau niet als mediërende factoren aangewezen kunnen worden.Show less
