Effect of Atomoxetine Treatment on Reading and Phonological Skills in Children with Dyslexia or Attention-Deficit/Hyperactivity Disorder and Comorbid Dyslexia in a Randomized, Placebo-Controlled Trial

The association between cognitive disengagement syndrome and specific learning disorder in children and adolescents with ADHD

This study aimed to examine the associations between Cognitive Disengagement Syndrome (CDS) and Specific Learning Disorder (SLD) in children and adolescents with Attention-Deficit/Hyperactivity Disorder (ADHD). We included sixty "ADHD-only" cases and eighty-two "ADHD + SLD" cases with an IQ score of 80 and above, aged 8-15. We applied both a structured psychiatric interview and a mental status examination. Parents completed the ADHD-Rating Scale IV, Barkley Child Attention Scale, and Specific Learning Disorder-Evaluation Scale. The sample consisted of 94 boys and 48 girls. The mean age of the cases was 10,90 ± 2,32. The "ADHD + SLD" group had a higher proportion of cases with CDS than the "ADHD-only" group (47,6% vs 15%). The "ADHD + SLD" group had significantly higher CDS-total, CDS-sluggish, and CDS-daydreaming scores than the "ADHD-only" group. SLD score was positively associated with CDS-total, CDS-sluggish, and CDS-daydreaming scores. Even when controlled for inattentive symptoms, IQ, drug treatment duration, socioeconomic level, and parental education level, CDS-daydreaming scores but not CDS-sluggish scores were associated with higher SLD scores. The findings indicate a prominent association between CDS and SLD. CDS symptoms -mainly- CDS-daydreaming symptoms are essentially associated with SLD even when controlled for inattentive symptoms, IQ, drug treatment duration, and relevant demographic factors. Therefore, clinicians should pay attention to a possible coexistence of CDS while evaluating cases with SLD.

Associative gene networks reveal novel candidates important for ADHD and dyslexia comorbidity

BACKGROUND

Attention deficit hyperactivity disorder (ADHD) is commonly associated with developmental dyslexia (DD), which are both prevalent and complicated pediatric neurodevelopmental disorders that have a significant influence on children's learning and development. Clinically, the comorbidity incidence of DD and ADHD is between 25 and 48%. Children with DD and ADHD may have more severe cognitive deficiencies, a poorer level of schooling, and a higher risk of social and emotional management disorders. Furthermore, patients with this comorbidity are frequently treated for a single condition in clinical settings, and the therapeutic outcome is poor. The development of effective treatment approaches against these diseases is complicated by their comorbidity features. This is often a major problem in diagnosis and treatment. In this study, we developed bioinformatical methodology for the analysis of the comorbidity of these two diseases. As such, the search for candidate genes related to the comorbid conditions of ADHD and DD can help in elucidating the molecular mechanisms underlying the comorbid condition, and can also be useful for genotyping and identifying new drug targets.

RESULTS

Using the ANDSystem tool, the reconstruction and analysis of gene networks associated with ADHD and dyslexia was carried out. The gene network of ADHD included 599 genes/proteins and 148,978 interactions, while that of dyslexia included 167 genes/proteins and 27,083 interactions. When the ANDSystem and GeneCards data were combined, a total of 213 genes/proteins for ADHD and dyslexia were found. An approach for ranking genes implicated in the comorbid condition of the two diseases was proposed. The approach is based on ten criteria for ranking genes by their importance, including relevance scores of association between disease and genes, standard methods of gene prioritization, as well as original criteria that take into account the characteristics of an associative gene network and the presence of known polymorphisms in the analyzed genes. Among the top 20 genes with the highest priority DRD2, DRD4, CNTNAP2 and GRIN2B are mentioned in the literature as directly linked with the comorbidity of ADHD and dyslexia. According to the proposed approach, the genes OPRM1, CHRNA4 and SNCA had the highest priority in the development of comorbidity of these two diseases. Additionally, it was revealed that the most relevant genes are involved in biological processes related to signal transduction, positive regulation of transcription from RNA polymerase II promoters, chemical synaptic transmission, response to drugs, ion transmembrane transport, nervous system development, cell adhesion, and neuron migration.

CONCLUSIONS

The application of methods of reconstruction and analysis of gene networks is a powerful tool for studying the molecular mechanisms of comorbid conditions. The method put forth to rank genes by their importance for the comorbid condition of ADHD and dyslexia was employed to predict genes that play key roles in the development of the comorbid condition. The results can be utilized to plan experiments for the identification of novel candidate genes and search for novel pharmacological targets.

ADHD-A Clinician's Bird's Eye View of Current Status and New Vistas!

Objectives

Literature on ADHD has taken long strides recently as heaps of new data are pouring in through countless papers. Here, authors try to outline changing paradigms in ADHD practice. DSM-5 changes regarding the typology and diagnostic criteria are highlighted. Overview of co-morbidities, associations, developmental trajectories, and syndromic continuity across lifespan is outlined. Recent insights into aetiology and diagnostic tools are briefly discussed. New medications in the pipeline are also described.

Methods

EMBASE, Ovid MEDLINE, PubMed, Scopus, Web of Science, and Cochrane Database of Systemic Reviews were searched for all relevant updates in ADHD literature as of June, 2022.

Results

DSM-5 brought about changes to the diagnostic criteria of ADHD. These included replacing types with presentations, pushing age to 12, and, incorporating adult diagnostic criteria. In the same vein, DSM-5 allows now for diagnosing concurrent ADHD and ASD. Associations of ADHD to allergy, obesity, sleep disorders, and, epilepsy have been demonstrated in recent literature. Neurocircuity underlying ADHD has been extended beyond frontal-striatal to include CTC as well as DMN accounting for ADHD heterogeneity. NEBA was FDA-approved to differentiate ADHD from hyperkinetic ID. Atypical antipsychotics use to address behavioural facets in ADHD is on the rise with no solid evidence-base. α-2 agonists are FDA-approved as monotherapy or adjunctive to stimulants. Pharmacogenetic testing is readily available for ADHD. Different formulations of stimulants abound on the market widening clinicians' repertoire. Stimulant-related exacerbation of anxiety and tics were challenged in recent studies. Drugs for ADHD in the pipeline include-dasotraline, armodafinil, tipepidine, edivoxetine, metadoxine, and memantine.

Conclusions

Literature on ADHD keeps expanding towards advancing our understanding of the complex and heterogeneous intricacies of this commonplace neurodevelopmental disorder and hence informing better decisions on how best to manage its diverse cognitive, behavioural, social and medical facets.

The effects of bilateral posterior parietal cortex tRNS on reading performance

According to established cognitive neuroscience knowledge based on studies on disabled and typically developing readers, reading is based on a dual-stream model in which a phonological-dorsal stream (left temporo-parietal and inferior frontal areas) processes unfamiliar words and pseudowords, whereas an orthographic-ventral stream (left occipito-temporal and inferior frontal areas) processes known words. However, correlational neuroimaging, causal longitudinal, training, and pharmacological studies have suggested the critical role of visuo-spatial attention in reading development. In a double blind, crossover within-subjects experiment, we manipulated the neuromodulatory effect of a short-term bilateral stimulation of posterior parietal cortex (PPC) by using active and sham tRNS during reading tasks in a large sample of young adults. In contrast to the dual-stream model predicting either no effect or a selective effect on the stimulated phonological-dorsal stream (as well as to a general multisensory effect on both reading streams), we found that only word-reading performance improved after active bilateral PPC tRNS. These findings demonstrate a direct neural connectivity between the PPC, controlling visuo-spatial attention, and the ventral stream for visual word recognition. These results support a neurobiological model of reading where performance of the orthographic-ventral stream is boosted by an efficient deployment of visuo-spatial attention from bilateral PPC stimulation.

Sensory white noise improves reading skills and memory recall in children with reading disability

BACKGROUND

Reading disability (RD) is characterized by slow and inaccurate word reading development, commonly reflecting underlying phonological problems. We have previously shown that exposure to white noise acutely improves cognitive performance in children with ADHD. The question addressed here is whether white noise exposure yields positive outcomes also for RD. There are theoretical reasons to expect such a possibility: a) RD and ADHD are two overlapping neurodevelopmental disorders and b) since prior research on white noise benefits has suggested that a central mechanism might be the phenomenon of stochastic resonance, then adding certain kinds of white noise might strengthen the signal-to-noise ratio during phonological processing and phoneme-grapheme mapping.

METHODS

The study was conducted with a group of 30 children with RD and phonological decoding difficulties and two comparison groups: one consisting of skilled readers (n = 22) and another of children with mild orthographic reading problems and age adequate phonological decoding (n = 30). White noise was presented experimentally in visual and auditory modalities, while the children performed tests of single word reading, orthographic word recognition, nonword reading, and memory recall.

RESULTS

For the first time, we show that visual and auditory white noise exposure improves some reading and memory capacities "on the fly" in children with RD and phonological decoding difficulties. By contrast, the comparison groups displayed either no benefit or a gradual decrease in performance with increasing noise. In interviews, we also found that the white noise exposure was tolerable or even preferred by many children.

CONCLUSION

These novel findings suggest that poor readers with phonological decoding difficulties may be immediately helped by white noise during reading. Future research is needed to determine the robustness, mechanisms, and long-term practical implications of the white noise benefits in children with reading disabilities.

Dyslexia treatment studies: A systematic review and suggestions on testing treatment efficacy with small effects and small samples

Poor response to treatment is a defining characteristic of reading disorder. In the present systematic review and meta-analysis, we found that the overall average effect size for treatment efficacy was modest, with a mean standardized difference of 0.38. Small true effects, combined with the difficulty to recruit large samples, seriously challenge researchers planning to test treatment efficacy in dyslexia and potentially in other learning disorders. Nonetheless, most published studies claim effectiveness, generally based on liberal use of multiple testing. This inflates the risk that most statistically significant results are associated with overestimated effect sizes. To enhance power, we propose the strategic use of repeated measurements with mixed-effects modelling. This novel approach would enable us to estimate both individual parameters and population-level effects more reliably. We suggest assessing a reading outcome not once, but three times, at pre-treatment and three times at post-treatment. Such design would require only modest additional efforts compared to current practices. Based on this, we performed ad hoc a priori design analyses via simulation studies. Results showed that using the novel design may allow one to reach adequate power even with low sample sizes of 30–40 participants (i.e., 15–20 participants per group) for a typical effect size of d = 0.38. Nonetheless, more conservative assumptions are warranted for various reasons, including a high risk of publication bias in the extant literature. Our considerations can be extended to intervention studies of other types of neurodevelopmental disorders.

The Mechanism, Clinical Efficacy, Safety, and Dosage Regimen of Atomoxetine for ADHD Therapy in Children: A Narrative Review

Atomoxetine, a selective norepinephrine (NE) reuptake inhibitor, was approved for attention deficit/hyperactivity disorder (ADHD) treatment in children, adolescents and adults. We searched the database PubMed/MEDLINE (2000 to October 1, 2021). Only publications in English were considered. Atomoxetine inhibits the presynaptic norepinephrine transporter (NET), preventing the reuptake of NE throughout the brain along with inhibiting the reuptake of dopamine in specific brain regions such as the prefrontal cortex (PFC). The novel mechanism of atomoxetine also includes several new brain imaging studies and animal model studies. It is mainly metabolized by the highly polymorphic drug metabolizing enzyme cytochrome P450 2D6 (CYP2D6). Atomoxetine is effective and generally well tolerated. ADHD is often accompanied by multiple comorbidities. A series of studies have been published suggesting that atomoxetine is effective in the treatment of ADHD symptoms for children with various types of comorbidity. In some cases, it is possible that atomoxetine may have a positive influence on the symptoms of comorbidities. Atomoxetine can be administered either as a single daily dose or split into two evenly divided doses, and has a negligible risk of abuse or misuse. The latest guideline updated that clinical dose selection of atomoxetine was recommended based on both CYP2D6 genotype and the peak concentration. To have a more comprehensive understanding of atomoxetine, this review sets the focus on the mechanism, clinical efficacy and dosage regimen in detail, and also touches on those studies regarding adverse reactions of atomoxetine.

Symptom scores and medication treatment patterns in children with ADHD versus autism

Most children with autism have ADHD, and children with ADHD-Combined and children with autism have high rates of irritable, oppositional, and aggressive behavior. Despite similar symptoms, prescribing practices may differ between autism and ADHD, which has not been examined in a single study. 1407 children with autism and 1036 with ADHD without autism, 2-17 years, were compared with 186 typical peers. Symptom scores were maternal Pediatric Behavior Scale ratings in eight areas (ADHD, oppositional/aggressive, irritable/angry, anxious, depressed, and social, writing, and learning problems). Psychotropics were prescribed to 38.0% with ADHD-Combined, 33.3% with autism, and 20.2% with ADHD-Inattentive, most often an ADHD medication (22.1% stimulant, 2.3% atomoxetine), antipsychotic (7.8%), SSRI (5.5%), and alpha agonist (4.9%). ADHD medications were more often prescribed than other medications in all diagnostic groups. Compared to autism, children with ADHD-Combined were more likely to be prescribed an ADHD medication, whereas antipsychotics and SSRIs were more likely to be prescribed in autism than in ADHD-Combined. Children with ADHD-Inattentive were least impaired and least likely to be medicated. More severely impaired children were more often medicated regardless of diagnosis. Symptom scores were far worse for treated and untreated children with ADHD and with autism than for typical peers.

Caffeine improves text reading and global perception

BACKGROUND

Reading is a unique human skill. Several brain networks involved in this complex skill mainly involve the left hemisphere language areas. Nevertheless, nonlinguistic networks found in the right hemisphere also seem to be involved in sentence and text reading. These areas do not deal with phonological information, but are involved in verbal and nonverbal pattern information processing. The right hemisphere is responsible for global processing of a scene, which is needed for developing reading skills.

AIMS

Caffeine seems to affect global pattern processing specifically. Consequently, our aim was to discover if it could enhance text reading skill.

METHODS

In two mechanistic studies (n=24 and n=53), we tested several reading skills, global and local perception, alerting, spatial attention and executive functions, as well as rapid automatised naming and phonological memory, using a double-blind, within-subjects, repeated-measures design in typical young adult readers.

RESULTS

A single dose of 200 mg caffeine improved global processing, without any effect on local information processing, alerting, spatial attention and executive or phonological functions. This improvement in global processing was accompanied by faster text reading speed of meaningful sentences, whereas single word/pseudoword or pseudoword text reading abilities were not affected. These effects of caffeine on reading ability were enhanced by mild sleep deprivation.

CONCLUSIONS

These findings show that a small quantity of caffeine could improve global processing and text reading skills in adults.

Reassessing health literacy best practices to improve medication adherence among patients with dyslexia

BACKGROUND

Dyslexia is characterized as unexpected and persistent difficulty in reading. In addition to language-based deficits, evidence indicates that people with dyslexia may struggle with tasks related to memory and executive function. This discussion paper explores how these non-linguistic deficits could plausibly affect medication adherence among patients with dyslexia.

DISCUSSION

There is a dearth of original research literature exploring the intersection of dyslexia and health behaviors in the United States. The authors examine selected best practices from the field of health literacy with potential to improve medication adherence among patients with dyslexia and suggest areas for further research on the intersection of dyslexia, health literacy and medication adherence.

CONCLUSION

Dyslexia is a high-prevalence condition. Patients with dyslexia may be more likely to experience challenges when learning and implementing complex, multi-step health behaviors, such as the tasks associated with medication adherence. However, there has been no research to assess the specific needs of patients with dyslexia, or design interventions to meet those needs. Foundational research is necessary to develop a health communications framework that meets the needs of these neurodiverse patients.

The Effects of ADHD Treatment and Reading Intervention on the Fluency and Comprehension of Children with ADHD and Word Reading Difficulties: A Randomized Clinical Trial

Many students with reading difficulties and disabilities (RD) also have Attention Deficit/Hyperactivity Disorder (ADHD). This randomized clinical trial compared the effects of ADHD treatment alone (medication, parent training), intensive reading intervention alone, and their combination on the reading fluency and comprehension of students with both disorders. Students with ADHD and RD were randomly assigned to receive (a) Reading Intervention only (n=74), (b) ADHD Treatment only (n=78), or (c) simultaneous Combined ADHD and RD Treatment (n=70). For phonemic decoding fluency, the Reading Intervention group and the Combined Treatment group both had significantly better outcomes than the ADHD Treatment group, but did not differ from one another. For passage comprehension, the ADHD Treatment group had significantly better outcomes than the Reading Intervention group, while the other groups did not differ from one another. ADHD treatment may support passage comprehension in this population, while fluent decoding is best supported through intensive reading intervention.

Using ADHD Medications to Treat Coexisting ADHD and Reading Disorders: A Systematic Review

Attention-deficit/hyperactivity disorder (ADHD), the most common pediatric neurobehavioral disorder, frequently presents with coexisting reading disorders (RDs). Despite this, it is unclear whether medication improves symptoms and function in children with comorbid ADHD and RD. We present a systematic review of studies investigating the effects of ADHD medications on ADHD symptoms, academic outcomes, and neuropsychological measures in this important group.

Gender-Dependent Changes in Time Production Following Quadrato Motor Training in Dyslexic and Normal Readers

Time estimation is an important component of the ability to organize and plan sequences of actions as well as cognitive functions, both of which are known to be altered in dyslexia. While attention deficits are accompanied by short Time Productions (TPs), expert meditators have been reported to produce longer durations, and this seems to be related to their increased attentional resources. In the current study, we examined the effects of a month of Quadrato Motor Training (QMT), which is a structured sensorimotor training program that involves sequencing of motor responses based on verbal commands, on TP using a pre-post design. QMT has previously been found to enhance attention and EEG oscillatory activity, especially within the alpha range. For the current study, 29 adult Hebrew readers were recruited, of whom 10 dyslexic participants performed the QMT. The normal readers were randomly assigned to QMT (n = 9) or Verbal Training (VT, identical cognitive training with no overt motor component, and only verbal response, n = 10). Our results demonstrate that in contrast to the controls, longer TP in females was found following 1 month of intensive QMT in the dyslexic group, while the opposite trend occurred in control females. We suggest that this longer TP in the female dyslexics is related to their enhanced attention resulting from QMT. The current findings suggest that the combination of motor and mindful training, embedded in QMT, has a differential effect depending on gender and whether one is dyslexic or not. These results have implications for educational and contemplative neuroscience, emphasizing the connection between specifically-structured motor training, time estimation and attention.

Psychopharmacotherapy of Attention Deficit-Hyperactivity Disorder in Children with Comorbid Conditions

One or more comorbidities occur in up to 80% of children with attention deficit-hyperactivity disorder. Attention deficit-hyperactivity disorder is also over-represented in several special populations. Pharmacotherapy can be challenging in these individuals with other conditions due to a suboptimal therapeutic response and an increased likelihood of adverse reactions. This article reviews the evidence supporting the psychopharmacologic management attention deficit-hyperactivity disorder when it occurs in individuals with common comorbidities.

Neural Noise Hypothesis of Developmental Dyslexia

Developmental dyslexia (decoding-based reading disorder; RD) is a complex trait with multifactorial origins at the genetic, neural, and cognitive levels. There is evidence that low-level sensory-processing deficits precede and underlie phonological problems, which are one of the best-documented aspects of RD. RD is also associated with impairments in integrating visual symbols with their corresponding speech sounds. Although causal relationships between sensory processing, print-speech integration, and fluent reading, and their neural bases are debated, these processes all require precise timing mechanisms across distributed brain networks. Neural excitability and neural noise are fundamental to these timing mechanisms. Here, we propose that neural noise stemming from increased neural excitability in cortical networks implicated in reading is one key distal contributor to RD.