Sluggish cognitive tempo and processing speed in adolescents with ADHD: do findings vary based on informant and task?

Unified and distinct cognitive control deficits in adolescents with cognitive disengagement syndrome and learning burnout

Introduction

Cognitive disengagement syndrome (CDS) is a psychological disorder characterized by daydreaming, mental fogginess, and slow thinking, while learning burnout (LB) is characterized by a passive and inattentive attitude toward learning. These two disorders are closely related but can be challenging to differentiate from one another. The present study aimed to identify shared and distinct cognitive control deficits between CDS and LB.

Methods

We recruited 136 adolescents (aged 14 to 17 years) from an initial screening of CDS and LB (N = 476) and divided them into four groups: CDS, LB, CDS + LB, and typically developing control. After a second screening, 129 adolescents completed two tasks to assess their attentional networks and cognitive control capacity (CCC).

Results

Adolescents with high CDS symptoms (both CDS group and CDS+LB group) exhibited impaired disengaging effect of attention and lower CCC, indicating deficits in orienting attention and the upper limit of information processing for cognitive control specifically. Furthermore, support vector machine modeling identified CCC as the most significant parameter differentiating the CDS and LB groups.

Discussion

Our findings suggest that while adolescents with high CDS and high LB symptoms have similar outward manifestations in the adolescent's school life, deficits in attention and cognitive control, particularly in the CCC, may distinguish between the two groups.

Exploring Subfactors of Adult Cognitive Disengagement Syndrome and Impact on Neuropsychological Performance

OBJECTIVE

This study investigated subfactors of cognitive disengagement syndrome (CDS; previously referred as sluggish cognitive tempo) among adults referred for neuropsychological evaluation of attentiondeficit/hyperactivity disorder (ADHD).

METHOD

Retrospective analyses of data from 164 outpatient neuropsychological evaluations examined associations between CDS subfactors and self-reported psychological symptoms and cognitive performance.

RESULTS

Factor analysis produced two distinct but positively correlated constructs: "Cognitive Complaints'' and "Lethargy." Both correlated positively with symptom reports (rs = 0.26-0.57). Cognitive Complaints correlated negatively with working memory, processing speed, and executive functioning performance (rs = -0.21 to -0.37), whereas Lethargy correlated negatively only with processing speed and executive functioning performance (rs = -0.26 to -0.42). Both predicted depression symptoms, but only Cognitive Complaints predicted inattention symptoms. Both subfactors demonstrated modest to nonsignificant associations with cognitive performance after accounting for estimated premorbid intelligence and inattention.

CONCLUSION

Findings indicate a bidimensional conceptualization of CDS, with differential associations between its constituent subfactors, reported symptoms, and cognitive performance.

[Formula: see text] Neurocognition in children with cognitive disengagement syndrome: accurate but slow

Cognitive disengagement syndrome (CDS), previously termed sluggish cognitive tempo (SCT), is characterized by excessive daydreaming, mental confusion, and slowed behavior or thinking. Prior research has found inconsistent relations between CDS and neurocognition, though most studies have used small or ADHD-defined samples, non-optimal measures of CDS, and/or examined limited neurocognitive domains. Accordingly, this study examined the association of parent- and teacher-reported CDS symptoms using a comprehensive neurocognitive battery in a sample of 263 children (aged 8-12) selected with a range of CDS symptomatology. Parents and teachers provided ratings of CDS and ADHD inattentive (ADHD-IN) symptoms. Path analyses were conducted to examine CDS and ADHD-IN as unique predictors of neurocognitive functioning after covarying for age, sex, and family income. CDS symptoms were uniquely associated with slower performance across a range of cognitive domains, including verbal inhibition, rapid naming/reading, planning, divided attention, and set shifting. In contrast, ADHD-IN symptoms were uniquely associated with poorer performance on a Go/NoGo task (inhibition/distractibility), visual scanning and discrimination, and interference control. Findings from the current study, amongst the first to recruit children based on levels of CDS symptomatology, provide the strongest evidence to date that the neurocognitive phenotype of CDS is characterized by slowed cognitive processing, and add to its validity as a separate syndrome from ADHD. If replicated, these findings have implications for assessment, treatment, and school accommodations for CDS. Neuroimaging studies exploring the neurobiological basis of CDS are also needed.

A Twin Study of the Relationships between Cognitive Disengagement Syndrome and Anxiety Phenotypes in Childhood and Adolescence

Data on the etiological factors underlying the co-occurrence of Cognitive Disengagement Syndrome (CDS) with anxiety symptoms are very limited. The present study investigated the nature of latent shared etiological elements in 400 Italian twin pairs aged 8-18, explaining the covariation between CDS and anxiety symptoms. Preliminary analysis demonstrated significant correlations between Child Behaviour Checklist/6-18 Sluggish Cognitive Tempo Scale and two (Somatic Anxiety, Generalized Anxiety) out of five Screen for Child Anxiety Related Disorders anxiety subscales. Results from causal analysis seem to exclude the hypothesis that co-occurrence between CDS and Anxiety Symptoms could be due to a direct phenotypic effect of one trait upon the other. Model fitting-analysis indicated that the aforementioned associations were partially explained by shared genetic and environmental factors influencing a common liability factor. A latent variable capturing the covariation between CDS and anxiety problems can be considered as a unifying (patho)physiological mechanism/system common to these constructs. Our results support the adoption of a broader view of the relationships between CDS and anxiety phenotypes in childhood and adolescence for both clinicians and educators.

Report of a Work Group on Sluggish Cognitive Tempo: Key Research Directions and a Consensus Change in Terminology to Cognitive Disengagement Syndrome

OBJECTIVE

The aim of this work was 2-fold: (1) to evaluate current knowledge and identify key directions in the study of sluggish cognitive tempo (SCT); and (2) to arrive at a consensus change in terminology for the construct that reflects the current science and may be more acceptable to researchers, clinicians, caregivers, and patients.

METHOD

An international Work Group was convened that, in early 2021, compiled an online archive of all research studies on SCT and summarized the current state of knowledge, noted methodological issues, and highlighted future directions, and met virtually on 10 occasions in 2021 to discuss these topics and terminology.

RESULTS

Major progress has been made over the last decade in advancing our understanding of SCT across the following domains of inquiry: construct measurement and stability; genetic, environmental, pathophysiologic, and neuropsychological correlates; comorbid conditions; functional impairments; and psychosocial and medication interventions. Findings across these domains are summarized, and potential avenues to pursue in the next generation of SCT-related research are proposed. Following repeated discussions on terminology, the Work Group selected "cognitive disengagement syndrome" (CDS) to replace "SCT" as the name for this construct. This term was deemed to best satisfy considerations that should apply when selecting terms for a condition or syndrome, as it does not overlap with established terms for other constructs, is not offensive, and reflects the current state of the science.

CONCLUSION

It is evident that CDS (SCT) has reached the threshold of recognition as a distinct syndrome. Much work remains to further clarify its nature (eg, transdiagnostic factor, separate disorder, diagnostic specifier), etiologies, demographic factors, relations to other psychopathologies, and linkages to specific domains of functional impairment. Investigators are needed with interests and expertise spanning basic, clinical, and translational research to advance our understanding and to improve the lives of individuals with this unique syndrome.

Pharmacologic Management of Cognitive Disengagement Syndrome (CDS) and Implications for Attention-Deficit/Hyperactivity Disorder (ADHD) Treatment: Emerging Treatments and Recommendations for Future Research

Although the study of cognitive disengagement syndrome (CDS; previously called sluggish cognitive tempo) first emerged in the 1980s, very little is known about treating CDS or its impact on evidence-based interventions for attention-deficit/hyperactivity disorder (ADHD) with which it frequently co-occurs. The objective of this leading article was to investigate the existing evidence on medication treatment and CDS, including studies that have examined CDS response to medication and CDS as a moderator of ADHD treatment response. A total of seven studies were identified. At present, the limited existing literature suggests that psychostimulants such as methylphenidate and lisdexamfetamine, as well as atomoxetine, may improve CDS symptoms, although replication and research on related medications is needed. However, there are indications that CDS symptoms may predict a reduced response to methylphenidate in children with ADHD. Although untested, research on the neurobiological, neuropsychological, and behavioral correlates of CDS point to a possible benefit of other ADHD medications (e.g., guanfacine), medications that treat narcolepsy (e.g., modafinil), and medications traditionally used to treat depression and anxiety (e.g., viloxazine, bupropion, fluvoxamine), some of which have also recently been used in ADHD management. The article concludes with recommendations for future research on pharmacologic treatment and CDS.

Executive Functions Contribute to the Differences Between ADHD and Sluggish Cognitive Tempo (SCT) in Adults

OBJECTIVES

This paper analyses the relationship between sociodemographic variables, executive dysfunctions, Sluggish Cognitive Tempo (SCT) and the mainly dimensions of ADHD: hyperactivity-impulsivity (ADHD-H/I) and inattention (ADHD-IN) in Brazilian adults.

METHOD

A cross-sectional, exploratory, and comparative design was used. A total of 446 participants (295 women) aging from 18 to 63 years old (M = 3,499 years, SD = 10.7) were recruited on the internet. Correlations, t independent tests and regressions were conducted.

RESULTS

Higher scores in ADHD dimensions were associated to more executive functioning problems and time perception distortions in comparison to those participants without significant ADHD symptoms. However, ADHD-IN dimension as well as SCT were higher associated with these dysfunctions than ADHD-H/I. The regression results showed that ADHD-IN was more related to Self-Management to time while ADHD-H/I to Self-Restraint and SCT to Self-Organization/Problem Solving.

CONCLUSION

This paper contributed to the distinction between SCT and ADHD in adults in important psychological dimensions.

Neuropsychological characteristics of children with Attention-Deficit/Hyperactivity Disorder and Sluggish Cognitive Tempo

OBJECTIVE

The present study aims to explore the neuropsychological features of children with Attention-Deficit/Hyperactivity Disorder (ADHD) and Sluggish Cognitive Tempo (SCT).

METHODS

Fifty-eight children with ADHD+SCT, 480 children with ADHD-SCT, and 105 healthy controls (HC) were recruited. Neuropsychological tests and the Behavior Rating Inventory of Executive Function (BRIEF) were used.

RESULTS

The ADHD+SCT group performed worse than the HC in processing speed (p = .005), set-shifting (p = .0003), interference control (p = .00014), and visual memory (p = .007), while the ADHD-SCT group performed worse than the HC in sustained attention measurements (all p < .0001). The ADHD+SCT group scored higher than the ADHD-SCT group in the following factors from BRIEF: plan/organize (p = .00083), working memory (p < .001), and shift (p = .0054).

CONCLUSION

Our results indicated that SCT symptoms are associated with worse executive function in children with ADHD except for sustained attention.

Co-occurring medical and behavioural conditions in children with Down syndrome with or without ADHD symptom presentation

BACKGROUND

Co-occurring attention deficit hyperactivity disorder (ADHD) is a challenge to characterise in the presence of other medical conditions commonly present in children with Down syndrome (DS). The current study examined differences among children with DS with or without ADHD symptomatology in terms of demographics, developmental level, co-occurring medical conditions, and parent and teacher ratings of behaviour and executive functioning.

METHODS

Parents and teachers of 108 school-age children with DS provided ratings of ADHD symptoms, behaviour problems and executive functioning skills. Children with DS and ADHD symptom presentation, as identified by a scoring algorithm, were compared with those without ADHD symptom presentation on demographic characteristics, developmental level, co-occurring medical conditions and parent-report and teacher-report measures of behaviours and executive functioning.

RESULTS

Sleep disorders, disruptive behaviour disorder, allergies and seizures were more common in children with DS and ADHD symptom presentation than in children without ADHD symptom presentation. After controlling for ADHD medication use, children with DS and ADHD symptom presentation had poorer performance than those without ADHD symptom presentation on parent behaviour ratings, teacher behaviour ratings and parent but not teacher ratings of executive functioning. No significant group differences in demographic characteristics or developmental level were identified.

CONCLUSIONS

Higher rates of co-occurring medical conditions present in children with DS and ADHD symptom presentation support the need for thorough differential diagnoses. The different pattern of group differences between parent-report and teacher-report has implications for diagnostic practices across settings as well as for treatment.

Sluggish Cognitive Tempo and Neuropsychological Functioning

Sluggish cognitive tempo (SCT) is marked by impairments across social, emotional, and academic functioning, but few studies have examined the association between SCT and neuropsychological functioning. The present study examined the associations between SCT and measures of processing speed, executive function, attention, and reaction time. From a larger sample of 8,238 children and adolescents, a subsample of 928 children were overselected for symptoms of SCT or attention-deficit/hyperactivity disorder (ADHD) and compared to a matched control sample of 652 individuals without elevations of ADHD or SCT (age range = 5.9-15.4 years). Multiple regression analyses revealed that symptoms of SCT were independently associated with deficits in nearly all domains assessed by a battery of neuropsychological assessments, including slower processing speed, poorer working memory, decreased inhibition, poorer vigilance, and increased reaction time. Further, weaknesses in all five of these domains remained significant even after symptoms of ADHD-inattention, anxiety, and depression were controlled. These findings add to literature that supports the validity of SCT as a symptom profile separate from ADHD-inattention symptoms.

Systematic Review: Assessment of Sluggish Cognitive Tempo Over the Past Decade

OBJECTIVE

To conduct a systematic review of the measures designed to assess sluggish cognitive tempo (SCT) since the first SCT scale using careful test-construction procedures was published in 2009.

METHOD

MEDLINE (PubMed), Embase, PsychINFO, and Web of Science databases were searched from September 2009 through December 2019. Articles reporting on reliability (internal consistency, test-retest, and interrater reliability), structural validity (an aspect of construct validity focused on items' convergent and discriminant validity), concurrent and longitudinal external validity, invariance, or intervention/experimental findings were included.

RESULTS

Full criteria for data extraction and inclusion were met by 76 studies. Nine measures for assessing SCT were identified (7 assessing parent report, teacher report, and/or self-report in children and 2 assessing self-report and/or collateral informant report in adults). Each measure demonstrated acceptable to excellent reliability. All or at least the majority of SCT items on each measure also had structural validity (high loadings on an SCT factor and low loadings on an attention-deficit/hyperactivity disorder [ADHD] inattention factor). Studies have supported the invariance of SCT across sex and time, and there is initial evidence of invariance across informants, youths with ADHD and youths without ADHD, and ADHD presentations. The Child and Adolescent Behavior Inventory (CABI), Child Concentration Inventory, Second Edition (CCI-2), and Barkley Adult ADHD Rating Scale-IV (BAARS-IV) have particularly strong support for assessing parent/teacher-reported, youth self-reported, and adult self-reported SCT, respectively.

CONCLUSION

The SCT measures included in this review share numerous positive properties, have promising psychometric support, and have proven useful for examining the external correlates of SCT across the life span. Although substantial progress has been made over the last decade, work remains to be done to further improve the assessment of SCT and key directions for future research are provided.

Preschool Neuropsychological Predictors of School-aged Sluggish Cognitive Tempo and Inattentive Behaviors

Sluggish cognitive tempo (SCT) is characterized by excessive daydreaming, slowed thinking, and mental confusion and 'fogginess'. A growing body of research supports the empirical differentiation of sluggish cognitive tempo (SCT) from the inattentive (IN) behaviors that characterize attention-deficit/hyperactivity disorder (ADHD). Further SCT and IN are uniquely associated with clinical correlates across academic, social, and emotional domains; however, there is limited understanding of how neuropsychological functioning contributes to SCT and/or IN behaviors. The two broad domains of neuropsychological functioning that have been most frequently examined in relation to SCT behaviors are processing speed and executive functions (EF). The present study tested whether EF and processing speed measured when children were on average age five years were predictive of teacher-rated IN and SCT behaviors in 1st - 3rd grades. Participants included 1,022 children from the Family Life Project, an ongoing prospective longitudinal study of child development in low-income, non-metropolitan communities. EF and processing speed uniquely made independent contributions to the prediction of IN and SCT. In secondary analyses that focused on specific facets of EF and processing speed, inhibitory control and working memory abilities predicted lower IN but not SCT behaviors, whereas slower processing speed significantly predicted both greater SCT and IN behaviors. These results are discussed as they inform developmental models of SCT and IN.

Sluggish Cognitive Tempo in Adolescents with and without ADHD: Differentiation from Adolescent-Reported ADHD Inattention and Unique Associations with Internalizing Domains

A growing number of studies support the internal and external validity of youth self-reported sluggish cognitive tempo (SCT) symptoms. However, no study has examined SCT in adolescents without ADHD, examined whether adolescent self-reported SCT is distinct from adolescent self-reported ADHD inattention (ADHD-IN), or evaluated whether links between SCT and internalizing problems differ for adolescents with or without ADHD. The present study is the first to (1) determine the convergent and discriminant validity of self-reported SCT and ADHD-IN symptoms in both adolescents with and without ADHD, (2) test the invariance of SCT and ADHD-IN symptoms across ADHD and comparison groups, (3) examine SCT as uniquely related to a range of internalizing-relevant domains, and (4) evaluate if the association between SCT with internalizing correlates differs for adolescents with or without ADHD. Participants were adolescents (Mage = 13 years) with (n = 162) and without (n = 140) ADHD. Adolescents and parents completed measures of internalizing symptoms and emotion dysregulation; adolescents completed measures of rumination and suicidal ideation. Analyses indicated that 13 of the 15 SCT items demonstrated convergent and discriminant validity from ADHD-IN, and SCT and ADHD-IN demonstrated invariance across the ADHD and comparison groups and across sex. SCT, but not ADHD-IN, was uniquely associated with greater adolescent-reported internalizing symptoms and suicidal ideation. Both SCT and ADHD-IN were uniquely associated with adolescent-reported emotion dysregulation and parent-reported internalizing symptoms. Only ADHD-IN was uniquely associated with parent-reported emotion dysregulation. Findings support the differentiation of adolescent-reported SCT and ADHD-IN and demonstrate associations between SCT and increased internalizing problems in adolescents with and without ADHD.