Neuropsychological Measures in the Diagnosis of ADHD in Preschool: Can Developmental Research Inform Diagnostic Practice?

Electrophysiological functional connectivity and complexity reflecting cognitive processing speed heterogeneity in young children with ADHD

Early intervention is imperative for young children with attention-deficit/hyperactivity disorder (ADHD) who manifest heterogeneous neurocognitive deficits. The study investigated the functional connectivity and complexity of brain activity among young children with ADHD exhibiting a fast cognitive processing speed (ADHD-F, n = 26), with ADHD exhibiting a slow cognitive processing speed (ADHD-S, n = 17), and typically developing children (n = 35) using wireless electroencephalography (EEG) during rest and task conditions. During rest, compared with the typically developing group, the ADHD-F group displayed lower long-range intra-hemispheric connectivity, while the ADHD-S group had lower frontal beta inter-hemispheric connectivity. During task performance, the ADHD-S group displayed lower frontal beta inter-hemispheric connectivity than the typically developing group. The ADHD-S group had lower frontal inter-hemispheric connectivity in broader frequency bands than the ADHD-F group, indicating ADHD heterogeneity in mental processing speed. Regarding complexity, the ADHD-S group tended to show lower frontal entropy estimators than the typically developing group during the task condition. These findings suggest that the EEG profile of brain connectivity and complexity can aid the early clinical diagnosis of ADHD, support subgrouping young children with ADHD based on cognitive processing speed heterogeneity, and may contain specific novel neural biomarkers for early intervention planning.

The Utility of a Novel Neuropsychological Measurement to Analyze Event-Related Attentional Behaviors among Young Children with Attention Deficit Hyperactivity Disorder-a Pilot Study

OBJECTIVE

The identification and diagnosis of children with attention deficit hyperactivity disorder (ADHD) traits is challenging during the preschool stage. Neuropsychological measures may be useful in early assessments. Furthermore, analysis of event-related behavior appears to be an unmet need for clinical treatment planning. Conners' Kiddie Continuous Performance Test (K-CPT) is the most popular well-established neuropsychological measurement but lacks event markers to clarify the heterogeneous behaviors among children. This study utilized a novel commercially available neuropsychological measure, the ΣCOG, which was more game-like and provided definite event markers of individual trial in the test.

METHODS

Thirty-three older preschool children (14 were diagnosed with ADHD, mean age: 66.21 ± 5.48 months; 19 demonstrated typical development, mean age: 61.16 ± 8.11 months) were enrolled and underwent comprehensive medical and developmental evaluations. All participants underwent 2 versions of neuropsychological measures, including the K-CPT, Second Edition (K-CPT 2) and the ΣCOG, within a short interval.

RESULTS

The study indicated the omissions and response time scores measured in this novel system correlated with clinical measurement of the behavioral scales in all participants and in the group with ADHD; additionally, associations with the traditional K-CPT 2 were observed in commissions and response time scores. Furthermore, this system provided a within-task behavioral analysis that identified the group differences in the specific trial regarding omission and commission errors.

CONCLUSIONS

This innovative system is clinically feasible and can be further used as an alternative to the K-CPT 2 especially in research by revealing within-task event-related information analysis.

EF Touch – Testbatterie zur Erfassung der exekutiven Funktionen bei 3- bis 5- Jährigen

Zusammenfassung. Vorschulkinder mit guten exekutiven Funktionen (EF) haben auch gute individuelle Voraussetzungen für die Schulbereitschaft und den Schulerfolg. Bislang fehlt jedoch im deutschsprachigen Raum eine Testbatterie für Kinder im Vorschulalter. Ziel der Arbeit war es daher, die Testbatterie EF Touch ( Willoughby & Blair, 2015 ) auf ihre Nutzbarkeit für den deutschen Sprachraum zu überprüfen. Die EF Touch wurde in einer Konstruktionsstichprobe von N = 90 Kindern (50 Mädchen; M-Alter = 3.39 Jahre, SD = 0.78) erprobt. Alle Aufgaben wiesen akzeptable bis sehr gute interne Konsistenzen auf (α = .51 – .93), die meisten korrelierten signifikant miteinander ( r = .39 – .51). Die zugrundeliegende Strukur der EF war erwartungsgemäß einfaktoriell. Zusätzlich zeigte sich ein signifikanter Zusammenhang ( r = -.43) mit der Elterneinschätzung der EF im Fragebogen BRIEF-P ( Daseking & Petermann, 2013 ). Es ergaben sich bei allen Aufgaben bessere Ergebnisse bei älteren Kindern. Nachdem die Nutzbarkeit der Testbatterie im deutschen Sprachraum gezeigt werden konnte, wird im nächsten Schritt eine repräsentative Normstichprobe erhoben.

Incremental Validity of Multi-Method and Multi-Informant Evaluations in the Clinical Diagnosis of Preschool ADHD

OBJECTIVES

This study investigated the discriminative validity of various single or combined measurements of electroencephalogram (EEG) data, Conners' Kiddie Continuous Performance Test (K-CPT), and Disruptive Behavior Disorder Rating Scale (DBDRS) to differentiate preschool children with ADHD from those with typical development (TD).

METHOD

We recruited 70 preschoolers, of whom 38 were diagnosed with ADHD and 32 exhibited TD; all participants underwent the K-CPT and wireless EEG recording in different conditions (rest, slow-rate, and fast-rate task).

RESULTS

Slow-rate task-related central parietal delta (1-4 Hz) and central alpha (8-13 Hz) and beta (13-30 Hz) powers between groups with ADHD and TD were significantly distinct (p < .05). A combination of DBDRS, K-CPT, and specific EEG data provided the best probability scores (area under curve = 0.926, p < .001) and discriminative validity to identify preschool children with ADHD (overall correct classification rate = 85.71%).

CONCLUSIONS

Multi-method and multi-informant evaluations should be emphasized in clinical diagnosis of preschool ADHD.

Task-Rate-Related Neural Dynamics Using Wireless EEG to Assist Diagnosis and Intervention Planning for Preschoolers with ADHD Exhibiting Heterogeneous Cognitive Proficiency

This study used a wireless EEG system to investigate neural dynamics in preschoolers with ADHD who exhibited varying cognitive proficiency pertaining to working memory and processing speed abilities. Preschoolers with ADHD exhibiting high cognitive proficiency (ADHD-H, n = 24), those with ADHD exhibiting low cognitive proficiency (ADHD-L, n = 18), and preschoolers with typical development (TD, n = 31) underwent the Conners’ Kiddie Continuous Performance Test and wireless EEG recording under different conditions (rest, slow-rate, and fast-rate task). In the slow-rate task condition, compared with the TD group, the ADHD-H group manifested higher delta and lower beta power in the central region, while the ADHD-L group manifested higher parietal delta power. In the fast-rate task condition, in the parietal region, ADHD-L manifested higher delta power than those in the other two groups (ADHD-H and TD); additionally, ADHD-L manifested higher theta as well as lower alpha and beta power than those with ADHD-H. Unlike those in the TD group, the delta power of both ADHD groups was enhanced in shifting from rest to task conditions. These findings suggest that task-rate-related neural dynamics contain specific neural biomarkers to assist clinical planning for ADHD in preschoolers with heterogeneous cognitive proficiency. The novel wireless EEG system used was convenient and highly suitable for clinical application.

Fish oil supplementation may improve attention, working memory and attention-deficit/hyperactivity disorder symptoms in adults with autism spectrum disorder: a randomised crossover trial

Marine n-3 fatty acids (n-3LCPUFA) have shown neurocognitive benefits in children with attention-deficit/hyperactivity disorder (ADHD), but few trials have examined effects in adults with autism spectrum disorder (ASD). We explored, if n-3LCPUFA affect cognitive functions in adults with ASD, and if effects are modified by comorbid ADHD. In a 2 × 4 week crossover study, twenty-six participants were randomised to sequence of supplementation with fish oil (FO, 5·2 g/d n-3PUFA) and safflower oil (SO). At baseline and after each period, we measured primary outcomes: attention (d2-test) and spatial working memory (Corsi test) and secondary outcomes: flexibility (Stroop word-colour test), ADHD symptoms (Conners scales), executive functions (Behavioural Inventory of Executive Function) and social behaviour (Social Responsiveness Scale). The dropout rate was 15 %. Compliance was 94 % and correlated with whole-blood n-3LCPUFA. Corsi scores improved by ∼0·3 × sd (P = 0·032) after FO v. SO, and the odds for d2 errors were 30 % lower (P = 0·016), which was supported by improved Conners scores of attention (P = 0·023). Improvement in Conners ADHD symptom score was limited to participants with ADHD (-3·5(-6·0; -1·0), n 10 v. -0·2(-2·5;2·2), n 11 without ADHD, Pinteraction = 0·096), who also improved their behavioural regulation index by 0·3 × sd after FO (Pinteraction = 0·016). Participants without ADHD gained most in d2 test performance (OR = 0·4(0·2;0·7) v. 0·9(0·6;1·3) in those with ADHD, Pinteraction = 0·002), but their executive function score was exacerbated after FO (5·9(0·0,11·8), Pinteraction = 0·039). Our results did not show any effects on ASD symptoms, but suggest that FO may improve attention and working memory in adults with ASD and ameliorate ADHD symptoms in those with comorbid ADHD.

Neural Dynamics for Facilitating ADHD Diagnosis in Preschoolers: Central and Parietal Delta Synchronization in the Kiddie Continuous Performance Test

The present study aimed to characterize children at risk of attention-deficit/hyperactivity disorder (ADHD) during preschool age and provide early intervention. The continuous performance test (CPT) and electroencephalography (EEG) can contribute additional valuable information to facilitate diagnosis. This study measured brain dynamics at slow and fast task rates in the CPT using a wireless wearable EEG and identified correlations between the EEG and CPT data in preschool children with ADHD. Forty-nine preschool children participated in this study, of which 29 were diagnosed with ADHD and 20 exhibited typical development (TD). The Conners Kiddie Continuous Performance Test (K-CPT) and wireless wearable EEG recordings were employed simultaneously. Significant differences were observed between the groups with ADHD and TD in task-related EEG spectral powers (central as well as parietal delta, P < 0.01), which were distinct only in the slow-rate task condition. A shift from resting to the CPT task condition induced overall alpha powers decrease in the ADHD group. In the task condition, the delta powers were positively correlated with the CPT perseveration scores, whereas the alpha powers were negatively correlated with specific CPT scores mainly on perseveration and detectability (P < 0.05). These results, which complement the findings of other sparse studies that have investigated within-task-related brain dynamics, particularly in preschool children, can assist specialists working in early intervention to plan training and educational programs for preschoolers with ADHD.

Zur Bedeutung auffälliger Exekutivfunktionen in der Diagnostik einer Aufmerksamkeitsdefizit-/Hyperaktivitätsstörung

Zusammenfassung. Defizite in Exekutivfunktionen und insbesondere in der Inhibitionsfähigkeit gelten verschiedenen Modellen zufolge als Kerndefizite einer Aufmerksamkeitsdefizit-/Hyperaktivitätsstörung (ADHS). Die Defizite sind sowohl auf einer Verhaltensebene als auch auf neurobiologischer Ebene belegt, finden aber bislang kaum Einzug in die klinische Diagnostik. Verschiedene Erhebungsverfahren werden vorgestellt und die Probleme im Bereich der klinischen Diagnostik skizziert. Viele Aufgaben messen nicht eine spezifische Exekutivfunktion, sondern umfassen immer auch andere kognitive Prozesse wie zum Beispiel Aufmerksamkeit oder Test- und Leistungsmotivation. Die Sensitivität vieler Aufgaben ist aufgrund der Heterogenität von ADHS durch verschiedene Entwicklungspfade oft nicht gewährleistet und Defizite in Exekutivfunktionen und der Inhibitionsfähigkeit sind auch nicht spezifisch für ADHS. Dennoch ist eine Diagnostik auffälliger Exekutivfunktionen und insbesondere von Defiziten in der Inhibitionsfähigkeit angebracht, da nur so Aussagen über zugrunde liegende Prozesse und Ursachen einer ADHS getroffen werden können, welche die Voraussetzung für gezielte Interventionen darstellen, wie zum Beispiel Inhibitionstrainings oder Neurofeedback.

A National Profile of Attention-Deficit Hyperactivity Disorder Diagnosis and Treatment Among US Children Aged 2 to 5 Years

OBJECTIVE

Clinical guidelines provide recommendations for diagnosis and treatment of attention-deficit hyperactivity disorder (ADHD), with specific guidance on caring for children younger than 6 years. This exploratory study describes ADHD diagnosis and treatment patterns among young children in the United States using 2 nationally representative parent surveys.

METHODS

The National Survey of Children's Health (2007-2008, 2011-2012) was used to produce weighted prevalence estimates of current ADHD and ADHD medication treatment among US children aged 2 to 5 years. The National Survey of Children with Special Health Care Needs (2009-2010) provided additional estimates on types of medication treatment and receipt of behavioral treatment among young children with special health care needs (CSHCN) with ADHD.

RESULTS

In 2011 to 2012, 1.5% of young children (approximately 237,000) had current ADHD compared to 1.0% in 2007 to 2008. In 2011 to 2012, 43.7% of young children with current ADHD were taking medication for ADHD (approximately 104,000). In young CSHCN with ADHD, central nervous system stimulants were the most common medication type used to treat ADHD, and 52.8% of young CSHCN with current ADHD had received behavioral treatment for ADHD in the past year.

CONCLUSION

Nearly a quarter million In young CSHCN have current ADHD, with a prevalence that has increased by 57% from 2007 to 2008 to 2011 to 2012. The demographic patterns of diagnosis and treatment described in this study can serve as a benchmark to monitor service use patterns of young children diagnosed with ADHD over time.

Transcranial direct current stimulation improves clinical symptoms in adolescents with attention deficit hyperactivity disorder

Anodal transcranial direct current stimulation (tDCS) of the prefrontal cortex has repeatedly been shown to improve working memory. As patients with attention deficit hyperactivity disorder (ADHD) are characterized by both underactivation of the prefrontal cortex and deficits in working memory that correlate with clinical symptoms, it is hypothesized that the modulation of prefrontal activity with tDCS in patients with ADHD increases performance in working memory and reduces symptoms of ADHD. To test this hypothesis, fifteen adolescents with ADHD (12-16 years old, three girls and 12 boys) were treated according to the randomized, double-blinded, sham-controlled, crossover design with either 1 mA anodal tDCS over the left dorsolateral prefrontal cortex or with the sham protocol 5 days each with a 2 weeks pause between these conditions. Anodal tDCS caused a significant reduction in clinical symptoms of inattention and impulsivity in adolescents with ADHD compared to sham stimulation. The clinical effects were supported by a significant reduction in inattention and hyperactivity in a standardized working memory test (QbTest). The described effects were more pronounced 7 days after the end of stimulation, a fact which emphasizes the long-lasting clinical and neuropsychological changes after tDCS. This study provides the first evidence that tDCS may reduce symptoms of ADHD and improve neuropsychological functioning in adolescents and points on the potential of tDCS as a form of treatment for ADHD.