Working memory and decision making in children with ADHD: an analysis of delay discounting with the use of the dual-task paradigm

Atypical sensory processing in adolescents with Attention Deficit Hyperactivity Disorder: A comparative study

Atypical sensory processing is common in Attention Deficit Hyperactivity Disorder (ADHD). Despite growing evidence that ADHD symptoms persist into adolescence, the sensory processing of individuals with ADHD in this age group is limited. The aim of this study was to assess differences in self-reported sensory experiences between adolescents with and without ADHD. One hundred thirty-eight Italian adolescents aged between 14 and 18 years (M=16.20; SD= ± 1.90) participated in the study. Sixty-nine participants with ADHD were matched by gender, age, and IQ to 69 typically developing individuals. The sensory processing of all participants was assessed using the Adolescent Sensory Profile (ASP) on the components: low registration, sensation seeking, sensory sensitivity, and sensation avoiding. Moreover, the modalities of ASP were measured: movement, vision, touch, activity level, hearing, and taste/smell. Results show that the ADHD group consistently displayed higher scores across all four components of the sensory profile compared to the control group. The subjects with ADHD also reported higher scores than the control group in all the modalities of ASP. These results confirming the presence of atypical sensory processing in adolescents with ADHD were discussed considering the Cumulative and Emergent Automatic Deficit model (CEAD).

Altered morphological characteristics and structural covariance connectivity associated with verbal working memory performance in ADHD children

OBJECTIVES

Deficits in verbal working memory (VWM) observed in attention deficit hyperactivity disorder (ADHD) children can persist into adulthood. Although previous studies have identified brain regions that are activated during VWM tasks, the neural mechanisms underlying the relationship between VWM deficits remain unclear. The objective of this study was to investigate the structural covariance network connectivity and brain morphology changes that are associated with VWM performance in ADHD children.

METHODS

For this study, we selected 26 ADHD children and 26 healthy control (HC) participants. Participants were instructed to perform an n-back VWM task and their accuracy and response times were subsequently recorded. This research utilised voxel-based morphometry to measure the grey matter (GM) volume and conducted structural covariance connectivity network analysis to explore the changes of brain in ADHD.

RESULTS

Voxel-based morphometry analysis showed that lower GM volume in the right cerebellum lobule VI and the left parahippocampal gryus in ADHD children. Moreover, a positive correlation was found between the GM volume in the right cerebellum lobule VI and the accuracy of 2-back VWM task with verbal, small reward, and delayed feedback (VSD). Structural covariance network analysis found decreased structural connectivity between right cerebellum lobule VI and right precentral gyrus, right postcentral gyrus, left paracentral lobule, right superior parietal gyrus, and left hippocampus in ADHD children.

CONCLUSIONS

The low GM volume and altered structural covariance connectivity in the right cerebellum lobule VI might potentially affect VWM performance in ADHD children.

ADVANCES IN KNOWLEDGE

The innovation of this study lies in its more focused discussion on the morphological characteristics and structural covariance connectivity of VWM deficits in ADHD children, and the innovative finding of a positive correlation between grey matter volume in the right cerebellum lobule VI and accuracy in completing the 2-back VWM task with verbal instructions, small reward, and delayed feedback (VSD). This expands upon previous research by elucidating the specific brain structures involved in VWM deficits in ADHD children and highlights the potential importance of the cerebellum in this cognitive process. Overall, these innovative findings advance our understanding of the neural basis of ADHD and may have important implications for the development of targeted interventions for VWM deficits.

COGMED working memory training in children with Attention Deficit/Hyperactivity Disorder (ADHD): A feasibility study in Saudi Arabia

Working memory training has been proven effective for improving cognitive functioning in patients with Attention Deficit/Hyperactivity Disorder (ADHD). However, the feasibility of this type of training for children in Saudi Arabia has not been previously explored. We investigated the feasibility of implementing Cogmed Working Memory Training (CWMT) in a sample of 29 Saudi children with ADHD. We found no significant demographic or clinical differences between compliant and noncompliant children. Although compliant children were initially better at following instructions and reported better improvements in working memory and math skills compared to those who did not complete the CWMT, all children who participated in the program showed improvements in performing the CWMT tasks. Most parents found the Cogmed training feasible for their children, were satisfied and keen to continue with the program, and felt the training helped them to address their problems. Most children did not encounter any difficulties in using the software, and many families were, therefore, likely to continue using the techniques from the program. We conclude that CWMT for children with ADHD is feasible in Saudi Arabia. Larger case-controlled studies are needed to thoroughly investigate the effects of CWMT compared to other interventions in Saudi children with ADHD.

ADHD Symptoms Increase Perception of Classroom Entropy and Impact Teacher Stress Levels

Attention deficit hyperactivity disorder (ADHD) is a common neuropsychiatric disorder among school-age children, characterized by persistent behavioral patterns of inattention and/or hyperactivity/impulsivity. These behaviors can create stress for teachers and negatively affect teacher-student interactions. This study hypothesized that a high frequency of ADHD students in the classroom can increase internal and external entropy, ultimately resulting in a negative stress impact on teachers. The physical concept of entropy, which measures the degree of disorder in a system, was used to better understand this relationship. The study evaluated 177 primary school teachers in their response to interacting with students with ADHD, using the Measurement of Psychological Stress (MPS) to evaluate subjective stress levels and the QUEIs and QUEIp questionnaires to measure structural and personal entropy. Path analysis was applied to identify the factors associated with the total score of MPS. The hypothesis was confirmed, as the frequency of ADHD students had a negative impact on teachers' entropy levels and personal entropy was found to significantly increase stress levels. The study highlights the negative impact of ADHD symptoms on stress levels and personal entropy of teachers when interacting with students with ADHD. These findings suggest the need for interventions aimed at balancing the frequency of students with ADHD and promoting positive training on stress reduction for teacher-student interactions.

Validity and Reliability of a Revised S-UPPS-P Impulsive Behavior Scale: The Interplay between Impulsivity and Working Memory

Impulsivity is a multidimensional construct. The UPPS-P model of impulsivity differentiates five distinct dimensions: negative urgency, positive urgency, lack of premeditation, lack of perseverance, and sensation seeking. The present study, reports the first translation and validation of the recently revised short form of the UPPS-P scale (S-UPPS-P) on a Persian-speaking sample, examining the relationship between impulsivity and working memory. who also completed the Positive and Negative Affect Scale (PANAS), the Buss and Perry Aggression Questionnaire, the Behavioral Inhibition and Activation Scales (BIS/BAS), and the Wechsler Digit Span Task (WDST). A series of confirmatory factor analyses, and Cronbach's alpha results supported the factor structure of the scale. The findings supported the S-UPPS-P model's hypothesized correlations with PANAS, aggressiveness, and the construct validity of the model. The results of hierarchical regression analysis showed that backward and forward digit span scores of the WDST predicted the S-UPPS-P impulsivity scores over the portion explained by BIS/BAS, PANAS, and aggression scores. To conclude, the revised S-UPPS-P Impulsive Behavior Scale was well supported even in a very different population than usually sampled, adding to growing evidence that it assesses distinct but interrelated aspects of the impulsivity construct. Our findings also suggest that attentional capacities and working memory play important roles in the prediction of impulsivity.

[Influence of sleep quality on symptoms in children with attention deficit hyperactivity disorder: the mediating role of working memory]

OBJECTIVES

To study the mediating role of working memory between sleep quality and symptoms in children with attention deficit hyperactivity disorder (ADHD).

METHODS

The cluster random sampling method was used to select 110 ADHD children and 124 normal children as subjects from grade 3-5 students in two primary schools in Kashgar, Xinjiang Uygur Autonomous Region, China. SNAP-IV, Pittsburgh Sleep Quality Index (PSQI), and visual-spatial working memory paradigm were used for investigation and comparison.

RESULTS

Compared with the normal group, the ADHD group had a significantly higher total score of PSQI and scores of subjective sleep quality, sleep latency, sleep efficiency, sleep disturbance, and a higher incidence of sleep quality problems (P<0.001). The working memory score in the ADHD group was significantly lower than that in the normal group (P<0.001). In the ADHD group, the working memory score was negatively correlated with the total score of PSQI (r_s=-0.271, P<0.001) and the score of symptoms (r_s=-0.439, P<0.001), and the total score of PSQI was positively correlated with the score of symptoms (r_s=0.540, P<0.001). Working memory had a partial mediating effect in the influence of sleep quality on symptoms in children with ADHD, accounting for 18.10% of the total effect.

CONCLUSIONS

Sleep quality issues are observed in some children with ADHD, and working memory plays a mediating role between sleep quality and symptoms in ADHD children.

New Drugs to Treat ADHD: Opportunities and Challenges in Research and Development

Since the landmark MTA (Multimodal Treatment of ADHD) trial unequivocally demonstrated the efficacy of methylphenidate, catecholaminergic drugs, especially stimulants, have been the therapeutic mainstay in treatment of Attention-Deficit Hyperactivity Disorder (ADHD). We review the new drugs which have entered the ADHD formulary. The lessons learned from drug-candidates that have succeeded in clinical trials together with those that have not have also been considered. What emerges confirms and consolidates the hypothesis that clinically effective ADHD drugs indirectly or directly increase catecholaminergic neurotransmission in the prefrontal cortex (PFC). Attempts to enhance catecholaminergic signalling through modulatory neurotransmitter systems or cognitive-enhancing drugs have all failed. New drugs approved for ADHD are catecholaminergic reuptake inhibitors and releasing agents, or selective noradrenaline reuptake inhibitors. Triple reuptake inhibitors with preferential effects on dopamine have not been successful. The substantial number of failures probably accounts for a continued focus on developing novel catecholaminergic and noradrenergic drugs, and a dearth of drug-candidates with novel mechanisms entering clinical development. However, substantial improvements in ADHD pharmacotherapy have been achieved by the almost exclusive use of once-daily medications and prodrugs, e.g. lisdexamfetamine and Azstarys^®, which improve compliance, deliver greater efficacy and reduce risks for diversion and abuse.

Animal Models of ADHD?

To describe animals that express abnormal behaviors as a model of Attention-Deficit Hyperactivity Disorder (ADHD) implies that the abnormalities are analogous to those expressed by ADHD patients. The diagnostic features of ADHD comprise inattentiveness, impulsivity, and hyperactivity and so these behaviors are fundamental for validation of any animal model of this disorder. Several experimental interventions such as neurotoxic lesion of neonatal rats with 6-hydroxydopamine (6-OHDA), genetic alterations, or selective inbreeding of rodents have produced animals that express each of these impairments to some extent. This article appraises the validity of claims that these procedures have produced a model of ADHD, which is essential if they are to be used to investigate the underlying cause(s) of ADHD and its abnormal neurobiology.

The Moderating Effect of Attention-Deficit Hyperactivity Disorder Symptoms on the Relationship Between Procrastination and Internalizing Symptoms in the General Adult Population

Background: The symptoms of attention-deficit hyperactivity disorder (ADHD) are known to exacerbate the effect of cognitive-behavioral impairments on emotional burden. Although adults with ADHD frequently experience procrastination and internalizing symptoms such as depression and anxiety, few studies have examined whether the association between procrastination and internalizing symptoms differs by ADHD symptoms. Objective: This study aimed to examine the moderating effect of ADHD symptoms on the association between procrastination and internalizing symptoms. Method: A cross-sectional survey was conducted among 470 adults (mean age=26.57, standard deviation=2.93) using self-reported questionnaires: Adult ADHD Self-Report Scale, General Procrastination Scales, Patient Health Questionnaire-9, and State-Trait Anxiety Inventory. Conclusion: Participants with more substantial ADHD symptoms experienced more procrastination and internalizing symptoms than those with the less substantial ADHD symptoms. Therefore, procrastination constitutes the treatment target for those suffering from ADHD and comorbid internalizing symptoms. Alternatively, there was no enhancing effect of ADHD symptoms on the association between procrastination and internalizing symptoms. It is necessary to examine more precise and valid hypotheses and underlying mechanisms of procrastination in high and low ADHD symptom groups.

Association of Attention Deficit/Hyperactivity Disorder With Events Occurring During Pregnancy and Perinatal Period

Background: The relationship of events occurring during pregnancy and perinatal period with attention deficit/hyperactivity disorder (ADHD) is not clear. Thus, the focus of the current study was to examine the effects of events occurring during pregnancy and perinatal period on ADHD.

Methods: A two-phase cross-sectional study was performed across 13 schools in Changsha and Yiyang cities from March to December, 2014. We preliminarily screened all students using CBCL and established the diagnosis using Mini International Neuropsychiatric Interview for Children and Adolescents (MINI-KID) and the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). A total of 3,418 questionnaires were effectively completed in this study.

Results: History of threatened abortion (TA) [odds ratio (OR): 1.707 (1.201–2.426)] (vs. No-TA) and neonatal asphyxia (NA) [OR: 2.497(1.225–5.09)] (vs. health) showed a positive association with ADHD. On subgroup analysis, TA [OR: 2.216 (1.458–3.369)] (vs. No-TA) was a risk factor for ADHD without comorbidity; instrumental delivery [OR: 2.748 (1.057–7.142)] (vs. natural birth) and NA [OR: 2.789 (1.222–6.361)] (vs. health) were risk factors for ADHD in the subgroup of ADHD with comorbidity; TA (vs. no-TA) and NA (vs. health) were risk factors for ADHD among male students [ORs: 2.232 (1.439–3.462) and 2.808 (1.115–7.068), respectively], while low birth weight (LBW) (vs. normal birth weight) was a risk factor [OR: 2.054 (1.063–3.967)] for ADHD among female students.

Conclusion: TA was a risk factor for ADHD in the absence of comorbid conditions; instrumental delivery and NA were risk factors for ADHD in the subgroup of ADHD with comorbidity; TA and NA were risk factors for ADHD among male students. LBW was a risk factor for ADHD among female students.

The relationship between theory of mind and sluggish cognitive tempo in school-age children with attention deficit and hyperactivity disorder

Sluggish cognitive tempo (SCT) is considered as a cognitive-emotional style. Theory of mind (ToM) skills form the basis of human cognition and social behavior. The aim of this study is to contribute to SCT literature by examining the relationship between SCT and cognitive and affective ToM in school-age children with attention deficit and hyperactivity disorder (ADHD). Fifty school-age children with ADHD (43 boys and seven girls) and 40 typically developing children (34 boys and six girls) were assessed using Parent-rated Barkley Child Attention Scale and Child Behavior Checklist/6-18, cognitive (first- and second-order ToM) and affective ToM (Reading Mind in the Eyes Test and Unexpected Outcomes Test (UOT)) tests. Multiple linear regression analysis was performed to determine the variables that may predict SCT levels in children with ADHD. Attention deficit and hyperactivity disorder-inattention (Exp(B) = .334, p = .027), internalization (Exp(B) = .305, p = .006), and UOT scores (Exp(B) = .933, p = .015) significantly predicted SCT severity in children with ADHD. SCT severity was significantly associated with impaired cognitive ToM skills as measured by second-order ToM (Exp(B) = 1.933, p = .045). Our findings may indicate that affective ToM developing with age, and impaired cognitive ToM skills are associated with increasing SCT severity.