Are sluggish cognitive tempo and daytime sleepiness distinct constructs?

Unique associations of ADHD and cognitive disengagement syndrome symptoms with sleep problems and circadian preference in adults

People with attention-deficit/hyperactivity disorder (ADHD) experience higher rates of sleep difficulties coupled with greater circadian preference for eveningness. Emerging evidence suggests that symptoms of cognitive disengagement syndrome (CDS) may be associated with sleep difficulties and eveningness preference independently of ADHD symptoms. However, most studies have been conducted with children, adolescents, or college students. This study examined unique associations between ADHD and CDS symptom dimensions and sleep problems and circadian preference in a non-referred sample of adults. 106 adults (ages 18-75 years; Mage = 38.69 years) completed self-report assessments of ADHD and CDS symptoms, sleep quality and functioning, and circadian preference. ADHD inattentive (ADHD-IN), ADHD hyperactive-impulsive (ADHD-HI), and CDS symptoms evinced differential unique associations in regression analyses. Only ADHD-IN symptoms were uniquely associated with more frequent sleep medication use. Only ADHD-HI symptoms were uniquely associated with shorter sleep duration and greater nighttime sleep disturbance. Only CDS symptoms were uniquely associated with poorer sleep quality, longer sleep onset latency, greater daytime dysfunction, greater global sleep impairment, and greater eveningness preference. Findings support the importance of considering the role of CDS in sleep disturbance and circadian preference in adults with ADHD and point to the need for careful assessment of these dimensions in research and clinical care.

Sluggish cognitive tempo in children and adolescents: circadian preference and digital gaming addiction

This study investigates the relationship between Sluggish Cognitive Tempo (SCT) and circadian preferences in children and adolescents. We also aimed to assess the relationship between digital game addiction and SCT, as existing literature is insufficient, particularly given the similarities between SCT and Attention Deficit Hyperactivity Disorder (ADHD) in relation to internalizing symptoms and comorbidity. This study involved 72 children and adolescents with SCT and 77 healthy controls, aged 11-16 years, who were referred to the Child and Adolescent Psychiatry outpatient clinic. We used Sociodemographic Data Form, Schedule for Affective Disorders and Schizophrenia for School-Age Children-Present and Lifetime Version- Turkish Version (K-SADS-PL), Turgay's DSM-IV Based Screening and Assessment Scale for Disruptive Behavior Disorders in Children and Adolescents (T-DSM-IV-S), Child and Adolescent Behavior Inventory-SCT (CABI-SCT), Children's Chronotype Questionnaire (CCQ), Digital Game Addiction Scale (DGAS). In the group with SCT, we found that eveningness preference and digital game addiction were statistically significant. Correlation analyses revealed a moderate positive relationship between chronotype scores (eveningness preferences higher scores) and digital game addiction. Additionally, a strong positive correlation was found between chronotype and SCT scale scores, as well as between digital game addiction and SCT scale scores. These findings highlight the potential role of digital game addiction and circadian preferences in shaping profile of SCT, providing valuable insights into the understanding of SCT symptoms.

Evaluation of sluggish cognitive tempo in children and adolescents with obesity and morbid obesity

ObjectiveThis study's primary aim is to evaluate the relationship between obesity and sluggish cognitive tempo (SCT).MethodThe study group consisted of obese (n = 37) and morbidly obese (n = 42) patients. The healthy control group included 38 children and adolescents. SCT was evaluated using the Barkley Child Attention Scale (BCAS). Clinical interviews were supplemented with standardized questionnaires to assess symptoms of depression, anxiety, and ADHD.ResultsBCAS scores were significantly higher in both the morbidly obese and obese groups than in the control group (p < .001). BCAS cutoff point showed that the prevalence of SCT was significantly higher in both the obese and morbidly obese groups compared to the control group (p < .001). Moreover, a logistic regression analysis identified screen time (OR = 1.330), maternal education (OR = 0.164), and BCAS scores (OR = 1.122) as independent risk factors for obesity.ConclusionThe current study found a significant relationship between SCT and obesity in children and adolescents. Given that obesity is a public health issue, our findings underscore the importance of evaluating SCT in morbidly obese and obese children. This understanding can lead to more comprehensive and effective treatment strategies for these children.

Exploring the link between sleep and cognitive disengagement syndrome (CDS) in young adults: Integrating the role of ADHD

OBJECTIVE

This study aimed to: (1) compare sleep quality and sleep-related parameters in a Turkish adult population with and without CDS and ADHD symptoms; and (2) re-examine the relationship between CDS and sleep by exploring potential associations between sleep problems and CDS symptoms, while also examining the separate roles of sluggishness and daydreaming, as well as possible gender differences.

METHOD

The study included 274 participants (age:18-35, 70.4 % female). The Adult CDS Ratings Scale, the Adult ADHD Self-Report Scale (ASRS), and the Pittsburgh Sleep Quality Index were used. The data were analyzed using SPSS 22 and AMOS 23. Statistical analyses included ANOVA with post-hoc Tamhane's test, Mann-Whitney U test, Spearman Correlation Analysis, and structural equation modeling with path analysis. Linear regression analysis was conducted to identify factors influencing daydreaming.

RESULTS

The study yielded four key findings: CONCLUSIONS: This study is among the first to explore the relationship between CDS symptoms and sleep problems in young adults, accounting for ADHD. Our findings highlight the significant association of hyperactivity/impulsivity and daydreaming with sleep quality, as well as the relationship between poor sleep quality and increased daydreaming and sluggishness, though to a lesser extent than ADHD symptoms. Notably, gender differences emerged, with poor sleep quality affecting CDS symptoms primarily in women, while sluggishness decreased with age in men. These results underscore the importance of considering sleep issues in the context of CDS and ADHD, particularly with attention to gender-specific patterns.

Is Cognitive Disengagement Syndrome a Risk Factor for Obese Children? A Case-Control Study

The aim of this study is to investigate whether there are differences in terms of cognitive disengagement syndrome (CDS) symptoms and some psychiatric symptoms between obese children and healthy controls. Participants were 60 cases diagnosed with obesity and 60 healthy children who were not obese/overweight aged 6-12 years. The obese group had significantly higher CDS symptom scores comparing to the control group. In the obese group, there were statistically significant associations found between the symptoms of CDS and attention, conduct issues, emotional instability, and excessive daytime sleepiness. Clinicians who work with obese children should also be aware of CDS symptoms.

Examining cognitive disengagement syndrome in a psychiatric outpatient sample: Psychometric support and associations with internalizing symptoms and sleep problems

OBJECTIVE

The internal (structural) and external validity of a self-report measure of cognitive disengagement syndrome (CDS, formerly sluggish cognitive tempo) relative to a self-report measure of attention-deficit/hyperactivity disorder-inattention (ADHD-IN) was evaluated with adults from university outpatient psychiatric clinics in Turkey.

METHODS

A total of 274 outpatients (75.9% women; ages 18-64 years; Mage  = 31.06; SDage  = 10.84; 50.4% anxiety disorders; 41.6% depressive disorders; 2.9% ADHD; 1.5% sleep disorders; 0.7% eating disorders; 2.9% no mental disorder) completed self-report measures of CDS, ADHD-IN, ADHD-hyperactivity/impulsivity (HI), sleep problems, depression, and stress.

RESULTS

All 15 CDS symptoms measured by the Adult Concentration Inventory (ACI) showed convergent (moderate to high loadings on the CDS factor) and discriminant (loading close to zero on the ADHD-IN factor) validity. CDS also showed stronger first-order and unique associations than ADHD-IN with sleep problems, depression, anxiety, and stress, whereas ADHD-IN showed stronger first-order and unique associations than CDS with ADHD-HI.

CONCLUSION

This is the first study to provide support for the scores from this 15 item self-report measure of CDS by the ACI in a clinical sample of adults, with findings consistent with previous studies examining parent and teacher rating scale measures with the same 15 CDS symptoms. These findings provide additional support for usefulness of these 15 CDS symptoms as measured by the ACI to study CDS across various cultures.

Cognitive Disengagement Syndrome and Child Sleep Problems in ADHD, Anxiety and Depression

The main objective of this study was to analyse the relationship and differential contribution of Cognitive Disengagement Syndrome (CDS) and sleep problems in children in different psychopathological measures. A total of 1133 participants (612 fathers/mothers and 521 children aged 7-13 years in Years 3-6 of Primary Education) completed the scales on CDS, sleep problems, depression (DEP), anxiety (ANX) and attention deficit and hyperactivity disorder (ADHD). Similar and significant correlations were identified in the measures of CDS and sleep problems between fathers and mothers, obtaining a high coefficient between the two parents. However, weak correlations were found between fathers/mothers and children. The scores of CDS and the sleep disturbance scale for children (SDSC) significantly predicted the internalising measures and ADHD, especially between SDSC and DEP. It was confirmed that sleep problems had a greater presence in the group of children with the highest ADHD scores, and especially in CDS and ADHD jointly. To conclude, the data indicate the importance of sleep problems in understanding CDS and its relationship with other psychopathological measures, especially ADHD, although to a greater extent with internalising symptoms, especially DEP.

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.

Sluggish cognitive tempo, eating habits, and daytime sleepiness in obese adolescents

OBJECTIVE

Rates of obesity have risen steeply in the western world in all age groups. Sluggish Cognitive Tempo (SCT) is characterized by a cluster of symptoms. Daytime sleepiness, commonly seen in obesity, may share a similar origin with sleepiness and daydreaming symptoms of SCT. This study aims to investigate the relationship between obesity, SCT, daytime sleepiness, and eating habits.

METHOD

Adolescents, aged between 10-17 years, with a BMI >95^th centile, were recruited to the study. Clinical interviews were supplemented with standardized questionnaires.

RESULTS

Of the 35 adolescents, more than one quarter (N = 10, 28.6%) had SCT. Emotional overeating and food enjoyment subscale scores showed moderate correlations with the SCT scores, though these associations were not significant when controlling for ADHD symptoms. Daytime sleepiness score in adolescents with SCT was found to be significantly higher than those without.

CONCLUSION

Sluggish Cognitive Tempo is frequently present in adolescents with obesity and associated with higher levels of emotional overeating, food enjoyment, and daytime sleepiness. Targeting aspects of SCT might offer additional avenues to assist in weight management programs for youth.

Sluggish cognitive tempo symptoms cooccurring with attention deficit hyperactivity disorder

Background

In the current study, the main aim was investigating the sociodemographic features and sluggish cognitive tempo symptoms of children diagnosed with attention deficit hyperactivity disorder and followed at an attention deficit hyperactivity disorder-specific outpatient clinic.

Results

The data of 200 boys and 200 girls who were followed up at the attention deficit hyperactivity disorder outpatient clinic were retrospectively compared. The scores of Turgay’s Scale-Disruptive Behavior Disorders Screening and Rating Scale, the Sluggish Cognitive Tempo subscale of the Children Behavior Checklist, and Conners Rating Scales Revised-Parent and Teacher Forms were analyzed. Among the group with Sluggish Cognitive Tempo scores, the ratio of girls was higher and the mean age at which symptoms of attention deficit hyperactivity disorder were recognized and treatment was offered was significantly older than that of the children with <4 scores. Both internalizing and externalizing symptoms were more frequent among the attention deficit hyperactivity disorder children who had Sluggish Cognitive Tempo scores ≥4.

Conclusions

There is increasing evidence distinguishing sluggish cognitive tempo from attention deficit hyperactivity disorder, and in this study, we would like to highlight the appearance and clinical manifestation of these disorders together. Further research, including Sluggish Cognitive Tempo children from the general population, is warranted to understand the characteristics that accompany and differentiate attention deficit hyperactivity disorder.

Academic functioning in children with and without sluggish cognitive tempo

Sluggish cognitive tempo (SCT) is increasingly conceptualized as a transdiagnostic set of symptoms associated with poorer functional outcomes, although the extent to which SCT is associated with academic functioning remains unclear. This study recruited children based on the presence or absence of clinically elevated SCT symptoms, using a multi-informant and multi-method design to provide a comprehensive examination of academic functioning in children with and without clinically elevated SCT symptoms. Participants were 207 children in Grades 2-5 (ages 7-11 years; 63.3% male), including 103 with clinically elevated teacher-reported SCT symptoms and 104 without elevated SCT, closely matched on grade and sex. A multi-informant, multi-method design that included standardized achievement testing, curriculum-based measurement (CBM), grades, classroom and laboratory observations, and parent and teacher rating scales was used. Children with elevated SCT symptoms had poorer academic functioning than their peers across most domains examined. Specifically, compared to children without SCT, children with elevated SCT had significantly lower grade point average (d = 0.42) and standardized achievement scores (ds = 0.40-0.77), poorer CBM performance including lower productivity (ds = 0.39-0.51), poorer homework performance and organizational skills (ds = 0.58-0.85), and lower teacher-reported academic skills (ds = 0.63-0.74) and academic enablers (ds = 0.66-0.74). The groups did not significantly differ on percentage of time on task during classroom observations or academic enabler interpersonal skills. Most effects were robust to control of family income, medication use, and attention-deficit/hyperactivity disorder inattentive symptoms, although effects for motivation and study skills academic enablers were reduced. This study demonstrates that children with clinically elevated SCT symptoms have wide-ranging academic difficulties compared to their peers without SCT. Findings point to the potential importance of assessing and treating SCT to improve academic outcomes.

A multi-method examination of sluggish cognitive tempo in relation to adolescent sleep, daytime sleepiness, and circadian preference

BACKGROUND

The field's understanding of the association between sluggish cognitive tempo (SCT) and sleep is severely limited by the lack of multi-method and multi-informant research designs that move beyond global ratings, often focused on a limited number of sleep-related domains, such as daytime sleepiness. The current study begins to address these limitations by using actigraphy, daily sleep diary, and self- and parent-report global ratings of sleep in adolescents, a developmental period marked by changes in SCT, sleep, and circadian function. As SCT and sleep are also associated with ADHD symptoms, we tested these associations in a sample of adolescents with and without ADHD.

METHODS

Adolescents (N = 302; M age = 13.17 years, 44.7% female) with (n = 162) and without ADHD (n = 140) and parents completed global ratings of sleep and daytime sleepiness, and adolescents completed a measure of circadian preference. Adolescents also wore actigraphs for approximately two weeks, during which daily diaries were completed.

RESULTS

Above and beyond demographic characteristics (i.e., sex, race, and family income), pubertal development, medication use, and ADHD group status, adolescents' self-reported SCT symptoms were uniquely associated with shorter sleep duration and later sleep onset per both actigraphy and daily diary. SCT symptoms were also uniquely associated with longer sleep onset latency and poorer overall sleep (per daily diary), more sleep/wake problems and daytime sleepiness (per adolescent rating), more difficulties initiating and maintaining sleep (per parent rating), and later eveningness preference (per adolescent rating). Nearly all significant effects remained in sensitivity analyses controlling for adolescent- or parent-reported ADHD symptom dimensions.

CONCLUSIONS

Findings provide the strongest evidence to date for SCT being uniquely linked to poorer sleep, greater daytime sleepiness, and a later evening circadian preference across subjective and objective measures. Longitudinal studies are needed to evaluate predictive and bidirectional associations.

Sluggish Cognitive Tempo as a Transdiagnostic Link Between Adult ADHD and Internalizing Symptoms

Objective

Although absent from traditional diagnostic nosologies, Sluggish Cognitive Tempo (SCT) may have transdiagnostic utility given its robust associations with ADHD and internalizing symptoms as well as with cognitive impairments common to these conditions. Within-person variation in SCT symptoms may also serve to link ADHD, cognitive deficits, and internalizing psychopathology, however, few studies have utilized intensive longitudinal designs to probe within-person variation in SCT and its links to cognitive deficits and psychopathology.

Method

Ecological Momentary Assessment was used to measure between and within-person variance in SCT 4 times per day across 7 days (28 time-points) in 158 college students (approximately 51% with elevated ADHD and/or internalizing symptoms). Participants also completed ratings of current and childhood ADHD symptoms, cognitive function and internalizing psychopathology. Parameters derived from longitudinal multilevel models indexing between and within person variation in SCT were examined as mediators of the associations between (1) ADHD and internalizing symptoms and (2) self-reported cognitive functioning and internalizing symptoms.

Results

Results indicated that between-person differences in SCT, but not within-person variability, linked current and childhood ADHD and internalizing symptoms. Similarly, problems in time-management and organization influenced internalizing psychopathology via between-person differences in SCT.

Conclusion

Results found that SCT may be a transdiagnostic link bridging mental health comorbidities, cognitive dysfunction, and internalizing psychopathology.

Sleep Disturbance and Its Association With Sluggish Cognitive Tempo and Attention in Pediatric Brain Tumor Survivors

Background

Pediatric brain tumor (PBT) survivors are at risk for developing sleep disturbances. While in other pediatric populations sleep disturbance has been associated with worse cognitive functioning, it is unclear to what extent this relationship generalizes to PBT survivors. The aim of the current study was to assess the relationship between sleep disturbance and aspects of cognition, including sluggish cognitive tempo (SCT) as well as attention and working memory.

Materials and Methods

Eighty-three PBT survivors 6–18 years of age who were at least 3 months post-treatment were included in the present cross-sectional study. Level of sleep disturbance was measured as a composite score reflecting various sleep problems as rated by caregivers. Cognitive measures included caregiver-ratings of sluggish cognitive tempo and attention problems, as well as performance-based cognitive measures assessing attention and executive functioning. Hierarchical regression analysis was used to assess associations between sleep and cognition.

Results

Of all caregivers, 32.5% reported one or more sleep disturbances as “very/often true” and over 68% of caregivers rated at least one sleep-related item as “somewhat true.” Of all cognitive variables, scores were most frequently impaired for SCT (30%). A higher level of sleep disturbance was associated with worse SCT and parent-rated attention problems. Associations between sleep and performance-based cognitive measures assessing attention and working memory were not statistically significant.

Conclusion

Findings of the current study highlight the importance of further investigation into the relationship between sleep and cognition in PBT survivors, which may assist efforts to maximize cognitive outcome and health-related quality of life in PBT survivors. The current study additionally suggests further investigation of SCT in this population is warranted, as it may be more sensitive to detecting possible associations with sleep disturbance relative to discrete measures that assess cognitive performance under ideal circumstances.

"My mom calls it Annaland": A Qualitative Study of Phenomenology, Daily Life Impacts, and Treatment Considerations of Sluggish Cognitive Tempo

Objective: To conduct qualitative analysis of interviews to understand phenomenology, daily life impact, and treatment considerations of sluggish cognitive tempo (SCT) behaviors in children and adolescents. Method: Youth with elevated SCT symptoms (N = 15, ages 9-16 years) and their parents completed interviews focused on their perception and daily life impact of SCT behaviors. Parents were also asked about intervention targets. Results: Parents and youth had both negative and positive perceptions of SCT, with SCT fostering creativity/imagination and a break from stressors while also negatively impacting daily functioning. The domains most frequently selected by parents as SCT intervention targets were academics, emotions, mind wandering, morning routines, and self-esteem. Conclusion: Children and their parents share negative and positive views of SCT behaviors, while also detailing specific ways that SCT negatively impacts day-to-day functioning. This study offers insights into possible intervention targets as provided by youth and parents directly impacted by SCT.

Sleep microstructure in attention deficit hyperactivity disorder according to the underlying sleep phenotypes

The analysis of sleep microstructure in attention deficit hyperactivity disorder (ADHD) revealed an under-representation of the EEG slow component during NREM sleep. Previous studies either excluded or did not characterize objectively sleep disorders, which notoriously affect sleep architecture. The present study aimed to investigate the cyclic alternating pattern in a real clinical sample of children with ADHD, in whom sleep disorders could be considered. Twenty-seven consecutively enrolled drug-naïve children (mean age, 10.53 years; nine females) and 23 controls (mean age, 10.22 years; 11 females) underwent a full sleep investigation, including attended video-polysomnography. Visual cyclic alternating pattern analysis was performed in a blinded way. Children with ADHD had one or more sleep disorders (a narcolepsy-like phenotype was found in two cases, sleep onset insomnia in three cases, arousal disorder in one case, movement disorder phenotype in six cases and obstructive sleep apnea in 11 cases, and six children had sleep-related epileptiform discharges). Children with ADHD and normal controls showed a similar microstructure with a cyclic alternating pattern rate of about 50%. Children with obstructive sleep apnea had a significantly higher cyclic alternating pattern rate during stage N3. Despite not reaching statistical differences, a lower cyclic alternating pattern rate and A1 index were found in children without epileptic abnormalities/obstructive sleep apnea. Our analysis might allow differentiation of the "primary form" of ADHD associated with a decrease of NREM instability from those forms associated with sleep apnea and epileptic activity.

Associations between sleep, daytime sleepiness and functional outcomes in adolescents with ADHD

OBJECTIVE/BACKGROUND

Adolescents with attention-deficit/hyperactivity disorder (ADHD) experience greater difficulties in the domains of sleep, daytime sleepiness, and functioning compared to their peers. However, the relationship between these domains has not been fully elucidated. This study aimed to examine the relationship between sleep problems (including daytime sleepiness), ADHD severity, and functional outcomes (irritability, sluggish cognitive tempo, homework difficulties, and substance use) in a sample of adolescents with ADHD.

PATIENTS/METHODS

Eighty-two adolescents (13-17 years) and their families participated in the study. Sleep was measured by both adolescent and parent-report. Adolescent irritability and sluggish cognitive tempo were reported by both adolescents and parents, while other variables were reported by a single reporter (homework difficulties - parent; ADHD severity - parent; substance use - adolescent). Analyses controlled for demographic factors and internalising and externalising comorbidities.

RESULTS

A weak relationship was found between adolescent-reported sleep problems and daytime sleepiness, which became non-significant in adjusted analyses (β = -0.19, p = 0.115). In adjusted analyses, there was an association between adolescent-reported sleep problems and adolescent-reported irritability (β = -0.27, p = 0.023) as well as between adolescent-reported daytime sleepiness and parent-reported sluggish cognitive tempo (β = 0.28, p = 0.033). In adjusted analyses, parent-reported adolescent sleep problems were associated with ADHD severity (β = 0.54, p = <0.001), parent-reported sluggish cognitive tempo (β = 0.64, p = <0.001), both reporters of irritability (parent-report: β = 0.32, p = 0.004; adolescent-report: β = 0.29, p = 0.022), and homework problems (β = 0.37, p = 0.003). Parent-reported daytime sleepiness was associated with parent-reported sluggish cognitive tempo (β = 0.34, p = 0.024).

CONCLUSIONS

This study demonstrates the importance of a holistic assessment of adolescents with ADHD, not only focusing on symptomatology but also on sleep problems and functional outcomes. The importance of multi-informant assessment of sleep problems is also reinforced.

Sluggish Cognitive Tempo and Daytime Sleepiness Mediate Relationships Between Sleep and Academic Performance

OBJECTIVE

Sleep difficulties, daytime sleepiness, and sluggish cognitive tempo (SCT) are associated with impairments in academic performance. SCT refers to symptoms of sluggishness, tiredness/lethargy, and slowed thinking/processing, but despite symptom overlap with sleepiness, research examining interrelations of SCT with sleep and daytime sleepiness is limited. The aims of this study were to evaluate the relationship between SCT and daytime sleepiness and to examine pathways between sleep, daytime sleepiness, SCT, and academic performance.

METHOD

Participants were a community sample of 1628 parents/caregivers of children aged between 6 and 10 years who completed questionnaires about their child's behavior, sleep, and academic performance. Confirmatory factor analysis was used to examine whether SCT was distinct from daytime sleepiness. Then, structural equation modeling was used to examine direct and indirect pathways between sleep (sleep-disordered breathing [SDB] symptoms, sleep duration, and latency), daytime sleepiness, SCT, and academic performance in reading, writing, and math.

RESULTS

SCT and daytime sleepiness were distinct but moderately correlated (r = 0.33, p ≤ 0.001). Sleep, in particular SDB symptoms, predicted increased SCT and daytime sleepiness. SCT was directly and negatively associated with all domains of academic performance, daytime sleepiness was associated with poorer reading performance, and longer sleep duration was directly associated with poorer math performance. SCT and, to a lesser extent, daytime sleepiness mediated effects of sleep on academic performance.

CONCLUSION

SCT symptoms are important for understanding how sleep difficulties affect academic performance in children. Sleep, daytime sleepiness, and SCT are interrelated but distinct factors that affect children's academic performance.

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.

Sluggish Cognitive Tempo in Adults Referred for an ADHD Evaluation: A Psychometric Analysis of Self- and Collateral Report

Objective: Sluggish cognitive tempo (SCT) symptoms uniquely contribute to psychiatric and functional outcomes in child samples; however, the psychometric properties of SCT measures among adult outpatients are unknown. Method: Adults (n = 124) presenting for an ADHD evaluation provided self- and collateral report of SCT symptoms. Results: The SCT scale had good internal consistency and yielded three factors across raters: Slow/Daydreamy, Sleepy/Sluggish, and Low Initiation/Persistence. SCT scores exhibited convergent validity with ADHD symptoms across raters. Individuals with ADHD received higher SCT ratings than those without ADHD via collateral report, a pattern that was similar when comorbidity was considered. SCT was associated with poorer functioning after accounting for ADHD symptoms with some differential effects based on reporting source. Conclusion: Findings support the internal consistency and validity of a three-factor SCT scale among adult outpatients. Differential results between self- and collateral report demonstrate the importance of multiple reporters of SCT in clinical settings.

Redefining ADHD Using an Adult Population: Should Inattention be Viewed as a Separate Dimension From Cognitive and Physiological Activity Level?

Objective: The purpose of this study was to reexamine the latent structure of ADHD and sluggish cognitive tempo (SCT) due to issues with construct validity. Two proposed changes to the construct include viewing hyperactivity and sluggishness (hypoactivity) as a single continuum of activity level, and viewing inattention as a separate dimension from activity level. Method: Data were collected from 1,398 adults using Amazon's MTurk. A new scale measuring activity level was developed, and scores of Inattention were regressed onto scores of Activity Level using curvilinear regression. Results: The Activity Level scale showed acceptable levels of internal consistency, normality, and unimodality. Curvilinear regression indicates that a quadratic (curvilinear) model accurately explains a small but significant portion of the variance in levels of inattention. Conclusion: Hyperactivity and hypoactivity may be viewed as a continuum, rather than separate disorders. Inattention may have a U-shaped relationship with activity level. Linear analyses may be insufficient and inaccurate for studying ADHD.

Correlates of Poor Sleep and Subsequent Risk of Misdiagnosis in College Students Presenting with Cognitive Complaints

Objectives

To examine the relationships of poor sleep to both subjective and objective cognitive functioning, attention deficit hyperactivity disorder (ADHD) and sluggish cognitive tempo (SCT) symptoms, and mental health variables in college students, controlling for noncredible symptom reporting and noncredible performance.

Methods

99 undergraduate students (Mage = 19.9, SD = 1.1), 60% female and 72% first-year students, completed a neuropsychological battery and self-report questionnaires at a single lab visit. 56% of the sample identified as “poor sleepers” (&gt;5 on the Pittsburgh Sleep Quality Index [PSQI]).

Results

Poor sleepers reported worse current (college grade point average [GPA]) but not past (high school GPA, American college test [ACT] score) academic performance. Additionally, they reported more mental health concerns, including depression and stress, but not anxiety. Poor sleepers reported more functional impairment and subjective cognitive concerns, including more Diagnostic and Statistical Manual of Mental Disorders (DSM) inattentive and hyperactive/impulsive symptoms, more SCT symptoms, and more executive dysfunction, even when controlling for depressive symptoms. However, poor sleepers did not differ from good sleepers on measures of objective cognition.

Conclusions

ADHD and SCT symptoms and concerns in college students may be related to poor sleep, which can lead to misdiagnosis for individuals presenting with ADHD-like complaints for the first time in college. Sleep difficulties may be modifiable with empirically supported sleep interventions; thus, in assessment for either of these presentations, a careful sleep history should be taken.

Excessive Daytime Sleepiness Measurements in Children With Attention Deficit Hyperactivity Disorder

Attention deficit hyperactivity disorder (ADHD) is the most commonly diagnosed neurodevelopmental disorder in childhood. It is a heterogeneous disorder in terms of clinical presentation that is probably due to the frequent occurrence of comorbidity. Children with ADHD more frequently report sleep disorders (notably delayed sleep phase syndrome) and excessive daytime sleepiness (EDS) than typically developing children. The aim of this article is to propose a narrative review of the assessment of EDS in the context of ADHD with first a summary of the subjective and objective tools used to measure it. Secondly, perspectives in terms of electroencephalogram (EEG) markers and neurofeedback are proposed. Then, possibilities for new kinds of evaluation are discussed (virtual reality, ecological momentary assessment, etc.). Lastly, we discuss specific clinical situations with EDS in the context of ADHD as links with narcolepsy, the comorbidity with other psychiatric disorders, and the context of sluggish cognitive tempo.

Sleep, Internalizing Problems, and Social Withdrawal: Unique Associations in Clinic-Referred Youth With Elevated Sluggish Cognitive Tempo Symptoms

Objective: We compared clinic-referred youth with ADHD + sluggish cognitive tempo (SCT; n = 34), ADHD Only (n = 108), and SCT Only (n = 22) on demographics, co-occurring symptomatology, comorbid diagnoses, and social functioning. Method: In total, 164 youth (age = 6-17 years, M = 9.97) and their parent(s) presented to an outpatient clinic for a psychoeducational assessment. Between-group analyses and regressions were used to examine study variables. Results: SCT groups were older and exhibited more parent-reported internalizing problems, externalizing problems, sleep problems, and social withdrawal on the Child Behavior Checklist. No significant differences emerged between groups on the Teacher Report Form. Regression analyses involving multiple covariates revealed that SCT symptoms were uniquely related to social withdrawal but not general social problems. Conclusion: Based on parent report, SCT symptoms have a unique relationship with internalizing problems, sleep problems, and social withdrawal. Future research should explore correlates of SCT in youth using multiple informants.

Prevalence, Patterns, and Predictors of Sleep Problems and Daytime Sleepiness in Young Adolescents With ADHD

Objective: The primary objective of this study was to evaluate the prevalence of multiple types of sleep problems in young adolescents with ADHD. Method: Adolescents comprehensively diagnosed with ADHD (N = 262) and their caregivers completed well-validated measures of sleep problems and daytime sleepiness. Participants also completed measures related to medication use, comorbidities, and other factors that could predict sleep problems. Results: Daytime sleepiness was by far the most common sleep problem, with 37% of adolescents meeting the clinical threshold according to parent report and 42% according to adolescent report. In contrast, prevalence rates for specific nighttime sleep problems ranged from 1.5% to 7.6%. Time spent in bed, bedtime resistance, ADHD inattentive symptoms, and Sluggish Cognitive Tempo (SCT) symptoms were significant in the final model predicting daytime sleepiness. Conclusion: Adolescents with ADHD commonly experience problems with daytime sleepiness that may significantly affect their functioning, but this may not be directly attributable to specific sleep problems.

ADHD and SCT Symptomatology in Relation to College Students' Use of Self-Regulated Learning Strategies

Objective: The present study examined the relation between self-regulated learning (SRL) strategies and ADHD and sluggish cognitive tempo (SCT) symptomatology. Method: Participants were 303 college students, aged 18 to 25 (M = 20.04, SD = 1.45), from a Midwestern university who completed the Barkley Adult ADHD Rating Scale-IV (BAARS-IV), and a shortened, generalized version of the Motivated Strategies for Learning Questionnaire (MSLQ). Results: Among college students, inattention symptomatology was consistently predictive of deficits in use of value, expectancy, and self-regulation strategies, while SCT symptomatology was only predictive of deficits in the use of self-regulation strategies. Conclusion: This study is the first to examine the relation between SCT symptomatology and SRL strategy use in college students. The findings revealed that SRL strategy use differs between college students exhibiting ADHD or SCT symptomatology. Remediation focusing on these deficits would likely increase academic achievement. Clinical implications, limitations, and suggestions for future research are discussed.

What cognitive processes are "sluggish" in sluggish cognitive tempo?

OBJECTIVE

Sluggish cognitive tempo refers to a constellation of symptoms that include slowed behavior/thinking, reduced alertness, and getting lost in one's thoughts. Despite the moniker "sluggish cognitive tempo," the evidence is mixed regarding the extent to which it is associated globally with slowed (sluggish) mental (cognitive) information processing speed (tempo).

METHOD

A well-characterized clinical sample of 132 children ages 8-13 years (M = 10.34, SD = 1.51; 47 girls; 67% White/non-Hispanic) were administered multiple, counterbalanced neurocognitive tests and assessed for sluggish cognitive tempo symptoms via multiple-informant reports.

RESULTS

Bayesian linear regressions revealed significant evidence against associations between sluggish cognitive tempo and computationally modeled processing speed (BF01 > 3.70), and significant evidence for associations with slower working memory manipulation speed. These findings were consistent across parent and teacher models, with and without control for attention-deficit/hyperactivity disorder inattentive symptoms and IQ. There was also significant evidence linking faster inhibition speed with higher parent-reported sluggish cognitive tempo symptoms.

CONCLUSIONS

These findings provide strong evidence against characterizing children with sluggish cognitive tempo symptoms as possessing a globally sluggish cognitive tempo. Instead, these symptoms appear to be related, to a significant extent, to executive dysfunction characterized by working memory systems that are too slow and inhibition systems that are too fast. Behaviorally, these findings suggest that requiring extra time to rearrange the active contents of working memory delays responding, whereas an overactive inhibition system likely terminates thoughts too quickly and therefore prevents intended behaviors from starting or completing, thereby giving the appearance that children are absent-minded or failing to act when expected. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Toward Establishing a Standard Symptom Set for Assessing Sluggish Cognitive Tempo in Children: Evidence From Teacher Ratings in a Community Sample

Despite increasing interest in sluggish cognitive tempo (SCT) in children, the field is stymied by the lack of a standard symptom set that can be used across studies. Without a standard symptom set, it is difficult to determine if differences across studies are due to methodological or sample differences, or simply the way SCT was measured. To move the field toward a standard symptom set, this study evaluates a teacher-report rating scale of SCT revised based on recent meta-analytic findings that identified optimal items for distinguishing SCT from attention-deficit/hyperactivity disorder inattention (ADHD-IN). Participants were 1,349 students (50.7% male) from grades 2 to 5. Teachers provided ratings of SCT, ADHD-IN, academic impairment, and social impairment. Exploratory structural equation modeling found 15 of the 16 SCT items to demonstrate excellent convergent validity and discriminant validity with ADHD-IN. The measurement properties of the SCT construct were also invariant across sex. SCT was uniquely associated with both academic and social impairment above and beyond ADHD-IN and sex. Although replication and extension is needed, the current study provides the strongest evidence to date of a possible standard symptom set that can be used across studies examining SCT in children.

Shorter REM latency in children with attention-deficit/hyperactivity disorder

The discrepancies in prior research about the actual sleep problems underlying attention-deficit/hyperactivity disorder (ADHD) demand more studies of children with this disorder. This study aimed to compare the subjective and objective sleep characteristics of 20 children with ADHD (DSM-IV criteria) and 20 typically developing children (aged 7-11 years). We assessed the children using sleep questionnaires and polysomnography recordings and analysed differences between the two groups using two-tailed Mann-Whitney U exact tests and Rosenthal's r as effect size measure. We also assessed associations between sleep measures and psychopathology using Spearman's correlation coefficients. No significant difference was found between the groups in almost any objective sleep variable, except for shorter REM latency in the ADHD group. Children with ADHD also showed significantly higher levels of daytime sleepiness and greater general sleep problems than control children, as reported by their parents, after discarding the primary sleep problems commonly associated with ADHD. Significant correlations were found between psychopathology and sleep measures. Our findings might support the link between narcolepsy-like sleep phenotype and ADHD. However, longitudinal research combining objective and subjective assessments should further explore the involvement of other variables, such as ADHD subtypes, medication, and comorbid symptoms in this relationship.

Sleep problems and daytime sleepiness in children with ADHD: Associations with social, emotional, and behavioral functioning at school, a cross-sectional study

Background: Sleep problems and daytime sleepiness are common in children with attention-deficit hyperactivity disorder (ADHD) and are associated with poor parent-reported functional outcomes. However, the potential impact of sleep problems or daytime sleepiness on the school functioning of children with ADHD remains unknown. We aimed to determine if sleep problems and daytime sleepiness were associated with the social, emotional, and behavioral school-based functioning of children with ADHD and comorbid sleep problems. Methods: Children aged 5-13 years with ADHD and a moderate-severe sleep problem (confirmed using American Academy of Sleep Medicine diagnostic criteria) were recruited from 43 pediatric practices across Victoria and Queensland, Australia (N = 257). Parent-rated sleep problems were assessed using the Children's Sleep Habits Questionnaire (CSHQ) and teacher-rated daytime sleepiness using the Teacher's Daytime Sleepiness Questionnaire. Teacher-rated social, emotional, and behavioral school functioning was assessed using three scales (peer problems, emotional problems, and conduct problems) from the Strength and Difficulties Questionnaire. Data was analyzed using Pearson correlations and linear regression models. Results: Teacher-rated daytime sleepiness was associated with higher levels of emotional (β = 0.39; 95% CI = 0.25-0.52) and behavioral problems (β = 0.47; CI = 0.36-0.58) in adjusted models. While total sleep duration and parent-rated sleep problems were not associated with daytime sleepiness or school functioning, the CSHQ subscale night wakings was correlated with teacher-rated daytime sleepiness (r = 0.21; p < 0.01). Conclusions: Daytime sleepiness (possibly as an indicator of sleep quality) may be a better predictor of school functioning in children with ADHD who have concomitant sleep problems than total sleep duration or parent-rated sleep problems.

Advancing the study of sluggish cognitive tempo via DSM, RDoC, and hierarchical models of psychopathology

Sluggish cognitive tempo (SCT) is separable from attention-deficit/hyperactivity disorder (ADHD) and other psychopathologies, and growing evidence demonstrates SCT to be associated with impairment in both children and adults. However, it remains unclear how SCT should optimally be conceptualized. In this article, we argue that multiple models of psychopathology should be leveraged to make substantive advances to our understanding of SCT. Both categorical and dimensional approaches should be used, including the Diagnostic and Statistical Manual of Mental Disorders (DSM) nosology, the Research Domain Criteria (RDoC) initiative, and hierarchical models of psychopathology. Studies are needed to determine whether individuals categorized with SCT can be reliably identified and differentiated from individuals without SCT in pathophysiological, neuropsychological, behavioral, and daily life functioning. Studies are also needed to evaluate the validity and utility of SCT as a transdiagnostic and dimensional construct. In considering SCT as a dimensional and potentially transdiagnostic construct, we describe ways in which SCT might be examined within the RDoC framework, including negative valence systems, cognitive systems, and arousal/regulatory systems, as well as within hierarchical models of psychopathology. Conceptualizing SCT within both categorical and dimensional models of psychopathology will help to better understand the causes, developmental pathways, and clinical implications of SCT, both as a construct in its own right and also in relation to other psychopathologies.

Clinical differentiation of sluggish cognitive tempo and attention-deficit/hyperactivity disorder in children

This study (a) determined whether clinical elevations of sluggish cognitive tempo (SCT) and attention-deficit/hyperactivity disorder (ADHD) symptom distributions in a large community sample of children would allow for identifying SCT-only, ADHD-only, and SCT + ADHD clinical groups; (b) examined co-occurrence of clinically elevated SCT and ADHD; (c) evaluated whether these clinical groups differed in their gender distribution, co-occurring mental health symptoms, or impairment in academic and social functioning; and (d) explored patterns of independence and overlap when clinically elevated depressive symptoms were considered in tandem with SCT and ADHD. Participants were mothers, fathers, and teachers of 2,142 children (50.51% boys, ages 8-13 years) from 32 schools in Spain. All three groups of informants completed measures of SCT, ADHD, oppositional defiant disorder (ODD), anxiety, depression, shyness, social impairment, and academic impairment. Cut-off scores for the top 5% of the sample were used to create SCT-only, ADHD-only, SCT + ADHD, and comparison groups. Across informants, 4.97%-5.53% met criteria for clinically elevated ADHD-only, and 2.30%-2.80% met criteria for clinically elevated SCT-only; 27%-35% of the ADHD group also met the criteria for the SCT group, whereas 44%-54% of the SCT group met the criteria for the ADHD group (primarily based on inattentive symptoms). The ADHD-only group had higher ODD scores than the SCT-only group, whereas the SCT-only group generally had higher shyness and internalizing scores (particularly depression) than the ADHD-only group. Additional analyses that also included clinically elevated depression revealed that 28-46% of the children with elevated SCT had elevations in neither ADHD nor depression. This study moves the field toward examining both the empirical and clinical differentiation of SCT and ADHD. Findings are discussed regarding how SCT may fit in diagnostic nosologies and models of psychopathology. (PsycINFO Database Record (c) 2018 APA, all rights reserved).

Sluggish Cognitive Tempo and Personality: Links to BIS/BAS Sensitivity and the Five Factor Model

We evaluated sluggish cognitive tempo (SCT) symptoms in relation to personality as assessed via both the Reinforcement Sensitivity Theory (BIS/BAS) and Five Factor (Big 5) Model of personality. 3,172 students from five universities completed psychopathology, BIS/BAS, and Big 5 measures. Correlations and path models with SCT, attention-deficit/hyperactivity disorder (ADHD) dimensions, and anxiety/depression in relation to personality were examined. SCT evidenced a different pattern of relations to adult personality than ADHD and anxiety/depression. SCT was significantly uniquely associated with higher BIS and Neuroticism, as well as higher BAS Fun-Seeking. SCT was uniquely associated with lower Extraversion and Conscientiousness. This study provides the first evidence linking SCT to adult personality and underscores the importance of differentiating SCT from both ADHD and anxiety/depression.

Sluggish Cognitive Tempo Symptoms Contribute to Heterogeneity in Adult Attention-Deficit Hyperactivity Disorder

Attention-deficit hyperactivity disorder (ADHD) persists into adulthood in over 50% of cases, although its associated symptom profiles, comorbid problems, and neuropsychological deficits change substantially across development. Sluggish cognitive tempo (SCT) symptoms may contribute to associations between ADHD and comorbid problems and may partially explain the substantial heterogeneity observed in its correlates. 349 adults aged 18-38 years (M = 23.2, SD = 4.5, 54.7% male, 61.03% with ADHD) completed a multi-informant diagnostic procedure and a comprehensive neuropsychological battery. Adults with ADHD (n = 213) were retained for analyses. Latent class analyses (LCA) revealed three profiles of SCT symptoms among those with ADHD, which we classified as minimal, moderate, or severe SCT. Multiple analysis of covariance (MANCOVA) revealed significant differences among these profiles, which remained when controlling for persistence of ADHD symptoms and sex. In general, adults with ADHD combined with SCT symptoms (moderate and severe) had significantly more symptoms of anxiety, depression, and persistent inattention, and had more severe professional and relational impairment compared to ADHD adults without SCT. Compared to those with moderate or minimal SCT symptoms, the severe SCT group had the most symptoms of depression and internalizing disorders, and the most impairment in the domain of daily responsibility. No significant differences based on externalizing symptoms emerged when controlling for sex and persistence of inattention symptoms, suggesting the moderate and severe SCT groups do not simply reflect more symptoms. Moreover, follow-up mediation analyses revealed that SCT might at least partially explain the heterogeneity in ADHD. Findings have implications for refinement of etiological conceptualization, assessment methods, and intervention strategies.

Sluggish cognitive tempo in adults: Psychometric validation of the Adult Concentration Inventory

[Correction Notice: An Erratum for this article was reported in Vol 30(3) of Psychological Assessment (see record 2017-30273-001). In the article, the Table 1 item content was incorrectly ordered. The table, as well as text referencing Table 1 in the Results and Discussion, have been corrected in all versions of this article.] As interest in sluggish cognitive tempo (SCT) increases, a primary limitation for the field is the lack of a unified set of symptoms for assessing SCT. No existing SCT measure includes all items identified in a recent meta-analysis as optimal for distinguishing between SCT and attention-deficit/hyperactivity disorder (ADHD) inattention. This study evaluates a new self-report measure for assessing SCT in adulthood, the Adult Concentration Inventory (ACI), which was developed in response to the meta-analytic findings for assessing SCT. Using a large, multiuniversity sample (N = 3,172), we evaluated the convergent and discriminant validity and reliability of the ACI. We also evaluated the ACI measure of SCT in relation to self-reported demographic characteristics, daily life executive functioning, socioemotional adjustment (i.e., anxiety/depression, loneliness, emotion dysregulation, self-esteem), and functional impairment. Exploratory confirmatory factor analyses resulted in 10 ACI items demonstrating strong convergent and discriminant validity from both anxiety/depressive and ADHD inattentive symptom dimensions. SCT was moderately to-strongly correlated with daily life EF deficits, poorer socioemotional adjustment, and greater global functional impairment. Moreover, SCT remained uniquely associated in structural regression analyses with most of these external criterion domains above and beyond ADHD. Finally, when internalizing symptoms were also covaried, SCT, but not ADHD inattention, remained significantly associated with poorer socioemotional adjustment. These findings support the use of the ACI in future studies examining SCT in adulthood and make a major contribution in moving the field toward a unified set of SCT items that can be used across studies. (PsycINFO Database Record

Are sluggish cognitive tempo symptoms associated with executive functioning in preschoolers?

The aim of this study is to investigate whether sluggish cognitive tempo (SCT) symptoms are associated with neurocognitive task performance and ratings of real-world executive functioning (EF) in preschoolers at risk for attention-deficit/hyperactivity disorder (ADHD). The associations between parent- and teacher-rated SCT symptoms and neuropsychological task performance and ratings of EF in 61 4-year-old preschool children (51 boys, 10 girls) with self-regulation difficulties were examined, with regression analyses controlling for the effects of ADHD inattention symptoms. In the study sample, higher teacher-rated SCT symptoms are significantly associated with poorer performance on tasks of visual-perceptual abilities, auditory and visual attention, sustained and selective attention, inhibitory control, pre-numerical/numerical concepts, and slower processing speed, but SCT symptoms are not significantly associated with working memory, attention shifting or cognitive flexibility when controlling for ADHD inattention. Higher parent-rated SCT symptoms are significantly associated with visual-perceptual abilities. ADHD inattention symptoms are more strongly associated than SCT with daily life EF ratings; neither parent- nor teacher-rated SCT symptoms are significantly associated with daily life ratings of inhibition, working memory, or planning/organization after controlling for ADHD inattention. This study suggests that SCT symptoms contribute to EF deficits at least on neurocognitive tasks assessing visual-perceptual/spatial abilities, attention to detail and processing speed, as observed in this sample of young children at risk for ADHD, and may be an important intervention target.

Sluggish Cognitive Tempo and Speed of Performance

OBJECTIVE

This study examined whether college students who reported higher levels of sluggish cognitive tempo (SCT) symptoms were actually more "sluggish" in their performance while completing speeded cognitive and academic measures.

METHOD

College students ( N = 253) completed self-reports of SCT and their reading and test-taking abilities as well as tests of processing speed, reading fluency, and reading comprehension.

RESULTS

Across all variables, SCT symptoms were most significantly associated with self-reported difficulty on timed reading tasks. However, students with high SCT scores were not significantly slower than controls on any of the timed tasks.

CONCLUSION

In college students, self-reports of high SCT levels do not suggest actual slow performance on cognitive and academic tasks.

Can Sluggish Cognitive Tempo Be Distinguished From ADHD Inattention in Very Young Children? Evidence From a Sample of Korean Preschool Children

OBJECTIVE

This study evaluated whether sluggish cognitive tempo (SCT) is separable from ADHD-inattention (IN) and uniquely associated with internalizing dimensions in preschool children in South Korea.

METHOD

Mothers of 172 preschool children (ages 4-6 years; 52% girls) rated children's SCT, ADHD-IN, ADHD-hyperactivity/impulsivity (HI), oppositional defiant disorder (ODD), aggression, emotional reactivity, anxiety/depression, somatic complaints, withdrawal, and sleep problems.

RESULTS

Eight of 10 SCT symptoms showed convergent and discriminant validity with ADHD-IN. ADHD-IN remained significantly positively associated with ADHD-HI, ODD, and aggressive behavior after controlling for SCT, whereas SCT was no longer positively associated with these externalizing behaviors after controlling for ADHD-IN. Both SCT and ADHD-IN were uniquely associated with greater emotionally reactivity, anxiety/depression, and withdrawal. Only SCT was uniquely associated with somatic complaints, and only ADHD-IN was uniquely associated with sleep problems.

CONCLUSION

Findings replicate results with children and adolescents, thus expanding evidence for the validity of SCT in early development.

Executive Dysfunction and Functional Impairment Associated With Sluggish Cognitive Tempo in Emerging Adulthood

OBJECTIVE

Research has identified a relationship between sluggish cognitive tempo (SCT) symptoms and symptoms of ADHD, anxiety, and depression; however, no study has controlled for symptoms of ADHD, anxiety, and depression when examining impairment related to SCT symptoms. This study aimed to examine (a) the extent to which functional impairment and executive function (EF) problems were accounted for by SCT symptoms when controlling for ADHD, anxiety, and depression symptoms, and (b) which type of symptoms were associated with the greatest amount of impairment.

METHOD

College students ( N = 458) completed self-report scales of ADHD, SCT, anxiety, and depression symptoms, as well as functional impairment and EF problems.

RESULTS

Thirteen percent of the sample was found to have high levels of SCT symptoms. SCT symptoms showed a moderate to strong correlation with the other symptom sets; however, high levels of SCT symptoms often occurred separate from high levels of ADHD, anxiety, or depression symptoms. SCT symptoms accounted for the most unique variance for both EF problems and functional impairment. Students with high levels of SCT symptoms, with or without high levels of ADHD symptoms, exhibited more impairment and EF problems than the controls.

CONCLUSION

SCT is a clinical construct worthy of additional study, particularly among college students.

"For Some Reason I Find it Hard to Work Quickly": Introduction to the Special Issue on Sluggish Cognitive Tempo

The body of research investigating the sluggish cognitive tempo (SCT) construct continues to accumulate at a rapid pace. This article provides an introduction to the Special Issue on SCT, which includes 10 empirical studies that collectively make a major contribution to the SCT knowledge base. Notably, the studies in this Special Issue include participants spanning in age from 4 to 64 years and from four continents, helping to move the field toward a life span, transcultural understanding of SCT. Together, these studies demonstrate that SCT symptoms can be distinguished from ADHD symptoms as early as preschool and that SCT does not fall under the overarching umbrella of ADHD. These studies also show SCT to be associated with a range of external correlates including internalizing symptoms, learning difficulties, functional impairment, and daily life executive functioning (but not performance-based measures of executive functions). Preliminary findings of SCT in relation to thyroid functioning and tobacco exposure are reported. In addition to providing a summary of the key themes across studies included in the Special Issue, this article highlights key ways in which future research can build from these studies. There is a particular need for research utilizing longitudinal, multi-method, and multi-informant designs that can shed light on the etiologies and developmental psychopathology of SCT across the life span.

Does Sluggish Cognitive Tempo Fit Within a Bi-Factor Model of ADHD?

OBJECTIVE

Studies demonstrate sluggish cognitive tempo (SCT) symptoms to be distinct from inattentive and hyperactive-impulsive dimensions of ADHD. No study has examined SCT within a bi-factor model of ADHD, whereby SCT may form a specific factor distinct from inattention and hyperactivity/impulsivity while still fitting within a general ADHD factor, which was the purpose of the current study.

METHOD

A total of 168 children were recruited from an ADHD clinic. Most (92%) met diagnostic criteria for ADHD. Parents and teachers completed measures of ADHD and SCT.

RESULTS

Although SCT symptoms were strongly associated with inattention, they loaded onto a factor independent of ADHD g. Results were consistent across parent and teacher ratings.

CONCLUSION

SCT is structurally distinct from inattention as well as from the general ADHD latent symptom structure. Findings support a growing body of research suggesting SCT to be distinct and separate from ADHD.

Pre-service teachers' perceptions of sluggish cognitive tempo

Sluggish cognitive tempo (SCT) is characterized by a passive form of inattention that may not overtly disrupt classroom goals. Due to the nature of these symptoms, children with SCT may be "falling through the cracks" in schools. The current study examined pre-service teachers' perceptions of SCT in the classroom. Undergraduate education majors (n = 161) read vignettes describing fictitious fourth-grade boys presenting with symptoms of SCT, attention-deficit/hyperactivity disorder (ADHD), or a non-ADHD-related control: social anxiety disorder (SA), and rated each of the vignettes in terms of their perceptions of the boy described. Results were analyzed using repeated measures ANOVAs and paired-sample t tests. Pre-service teachers viewed all three sets of symptoms as concerning, but viewed ADHD behaviors as the most problematic. These results are promising, as they suggest that pre-service teachers are concerned about both hyperactive (i.e., ADHD) and non-hyperactive behavioral problems (i.e., SCT and SA). Implications and future directions are discussed.

Sluggish Cognitive Tempo is Associated With Poorer Study Skills, More Executive Functioning Deficits, and Greater Impairment in College Students

OBJECTIVES

Few studies have examined sluggish cognitive tempo (SCT) in college students even though extant research suggests a higher prevalence rate of SCT symptoms in this population compared to general adult or youth samples. The current study examined SCT symptoms in relation to two domains related to college student's academic success, study skills and daily life executive functioning (EF), as well as specific domains of functional impairment.

METHOD

158 undergraduate students (M_age = 19.05 years; 64% female) completed measures of psychopathology symptoms, study skills, daily life EF, and functional impairment.

RESULTS

After controlling for demographics and symptoms of attention-deficit/hyperactivity disorder (ADHD), anxiety, and depression, SCT remained significantly associated with poorer study skills, greater daily life EF deficits, and global impairment and with greater functional impairment in the specific domains of educational activities, work, money/finances, managing chores and household tasks, community activities, and social situations with strangers and friends. In many instances, ADHD inattentive symptoms were no longer significantly associated with study skills or impairment after SCT symptoms were added to the model.

CONCLUSION

SCT is associated with poorer college student functioning. Findings highlight the need for increased specificity in studies examining the relation between SCT and adjustment.

Sluggish cognitive tempo in children referred to a pediatric Sleep Disorders Center: Examining possible overlap with sleep problems and associations with impairment

Research supports the distinctness of sluggish cognitive tempo (SCT) (e.g., mental confusion and slowed behavior/thinking) from other psychopathologies. However, the relation between SCT and sleep functioning has not been adequately studied. We examined the association between SCT and sleep functioning in 325 children (62% male) ages 6-10 years referred to a pulmonary-based, accredited Sleep Disorders Center. Correlations between caregiver ratings of SCT, other psychopathologies (i.e., inattention/hyperactivity, oppositionality, depression, anxiety), sleep functioning (both behavioral and organic symptoms), as well as sleep disorder diagnoses, were examined. Unique effects of SCT and other psychopathologies on sleep problem severity controlling for child demographics were assessed using regressions. Regression analyses were also conducted to examine the unique effects of SCT on impairment (i.e., academic difficulties, parenting stress, and other psychopathologies) controlling for child demographics, sleep problem severity, and other psychopathology symptoms. SCT was weakly to moderately correlated with most measures of sleep (rs = .07-.39) and moderately to strongly correlated with measures of daytime sleepiness (rs = .33 and .53). In the regression analyses, SCT was uniquely associated with greater sleep functioning severity and impairment in academic functioning. SCT was also uniquely associated with higher levels of depression and inattention/hyperactivity, but not anxiety, and negatively associated with oppositionality. Finally, SCT symptoms were uniquely associated with greater parent-child dysfunctional interaction. Findings demonstrate that SCT is related to, but not redundant with, sleep problems and daytime sleepiness specifically. Further, SCT remained associated with several domains of functional impairment in sleep-disordered children after controlling for clinically-relevant variables, highlighting the potential value in assessing SCT symptoms in children with sleep problems.

The Internal, External, and Diagnostic Validity of Sluggish Cognitive Tempo: A Meta-Analysis and Critical Review

OBJECTIVE

To conduct the first meta-analysis evaluating the internal and external validity of the sluggish cognitive tempo (SCT) construct as related to or distinct from attention-deficit/hyperactivity disorder (ADHD) and as associated with functional impairment and neuropsychological functioning.

METHOD

Electronic databases were searched through September 2015 for studies examining the factor structure and/or correlates of SCT in children or adults. The search procedures identified 73 papers. The core SCT behaviors included across studies, as well as factor loadings and reliability estimates, were reviewed to evaluate internal validity. Pooled correlation effect sizes using random effects models were used to evaluate SCT in relation to external validity domains (i.e., demographics, other psychopathologies, functional impairment, and neuropsychological functioning).

RESULTS

Strong support was found for the internal validity of the SCT construct. Specifically, across factor analytic studies including more than 19,000 individuals, 13 SCT items loaded consistently on an SCT factor as opposed to an ADHD factor. Findings also support the reliability (i.e., internal consistency, test-retest reliability, interrater reliability) of SCT. In terms of external validity, there is some indication that SCT may increase with age (r = 0.11) and be associated with lower socioeconomic status (r = 0.10). Modest (potentially negligible) support was found for SCT symptoms being higher in males than females in children (r = 0.05) but not in adults. SCT is more strongly associated with ADHD inattention (r = 0.63 in children, r = 0.72 in adults) than with ADHD hyperactivity-impulsivity (r = 0.32 in children, r = 0.46 in adults), and it likewise appears that SCT is more strongly associated with internalizing symptoms than with externalizing symptoms. SCT is associated with significant global, social, and academic impairment (r = 0.38-0.44). Effects for neuropsychological functioning are mixed, although there is initial support for SCT being associated with processing speed, sustained attention, and metacognitive deficits.

CONCLUSION

This meta-analytic review provides strong support for the internal validity of SCT and preliminary support for the external validity of SCT. In terms of diagnostic validity, there is currently not enough evidence to describe SCT in diagnostic terms. Key directions for future research are discussed, including evaluating the conceptualization of SCT as a transdiagnostic construct and the need for longitudinal research.

Uncovering a clinical portrait of sluggish cognitive tempo within an evaluation for attention-deficit/hyperactivity disorder: A case study

Despite the burgeoning scientific literature examining the sluggish cognitive tempo (SCT) construct, very little is known about the clinical presentation of SCT. In clinical cases where SCT is suspected, it is critical to carefully assess not only for attention-deficit/hyperactivity disorder (ADHD) but also for other comorbidities that may account for the SCT-related behaviors, especially internalizing symptoms and sleep problems. The current case study provides a clinical description of SCT in a 7-year-old girl, offering a real-life portrait of SCT while also providing an opportunity to qualitatively differentiate between SCT and ADHD, other psychopathologies (e.g. depression, anxiety), and potentially related domains of functioning (e.g. sleep, executive functioning [EF]). "Jessica" was described by herself, parents, and teacher as being much slower than her peers in completing schoolwork, despite standardized testing showing Jessica to have above average intelligence and academic achievement. Jessica's parents completed rating scales indicating high levels of SCT symptoms and daytime sleepiness, as well as mildly elevated EF deficits. More research is needed to determine how to best conceptualize, assess, and treat SCT, and Jessica's case underscores the importance of further work in this area.

Sleep habits in children with attention-deficit/hyperactivity disorder predominantly inattentive type and associations with comorbid psychopathology symptoms

OBJECTIVES

Much of what is currently known about the sleep functioning of children with attention-deficit/hyperactivity disorder (ADHD) is based on samples of children with ADHD combined type, and no study to date has examined the association between sluggish cognitive tempo (SCT) and sleep functioning in children diagnosed with ADHD. Accordingly, the objectives of this study were to (1) describe the sleep habits of children diagnosed with ADHD predominantly inattentive type (ADHD-I) and (2) examine whether comorbid internalizing, oppositional, and/or SCT symptoms are associated with poorer sleep functioning in children with ADHD-I. This study extends the current literature by using a large, clinical sample of children with ADHD-I to examine the association between SCT and other psychopathology symptoms with children's sleep functioning.

METHODS

Participants included 147 children (age: 6-11, 59% male, 55% White) diagnosed with ADHD-I using a semi-structured diagnostic interview. Parents completed measures assessing their child's sleep habits as well as comorbid anxiety, depression, oppositionality, and SCT symptoms.

RESULTS

Fourteen percent of children with ADHD-I obtain less sleep than recommended and 31% have a sleep onset latency of greater than 20 minutes. The few children taking medication for ADHD had a longer sleep onset latency than those without medication. Twenty-seven percent of parents indicated that it is "difficult" to get their child out of bed on school days and 41% of parents indicated that their child needs to catch-up on sleep on the weekend "at least a little". Regression analyses found anxiety and SCT sleepy/tired symptoms to be the most consistent dimensions of psychopathology associated with sleep functioning, with little support for depression or oppositionality being associated with sleep.

CONCLUSIONS

A sizeable minority of children with ADHD-I experience impaired sleep. In addition to SCT sleepy/tired symptoms, comorbid anxiety was most consistently associated with poorer sleep functioning in children with ADHD-I. SCT daydreaming and working memory symptoms were unassociated with sleep functioning, and the size of the effects between SCT sleepy/tired and sleep functioning indicates that these are not overlapping constructs. Longitudinal studies are needed to evaluate the interrelations of sleep problems and comorbid psychopathology symptoms and their impact on the daytime functioning of children with ADHD-I.

Sleep Difficulties are Associated with Parent Report of Sluggish Cognitive Tempo

OBJECTIVE

Sleep disturbance is considered both a behavioral symptom of and a contributor to functional difficulties in children with attention-deficit/hyperactivity disorder (ADHD). The construct of sluggish cognitive tempo (SCT) has also been linked to ADHD; however, little is known regarding the effects of sleep specifically on SCT symptoms. This study examined the association between parent-reported sleep disturbance and parent- and teacher-reported SCT, while controlling for the effects of ADHD and mood symptoms.

METHOD

Participants included 746 clinically referred children (65% male, age range: 5-18 years) with both parent and teacher ratings assessing symptoms of ADHD, mood symptoms (depression, anxiety), and SCT. Parents/caregivers also rated their child's sleep problems with regard to 4 core concerns: falling asleep, sleep restlessness, difficulty waking, and breathing difficulties. The SCT scale included three empirically derived subscales: sleepy/sluggish, low initiation/persistence, and daydreamy.

RESULTS

After accounting for age, medication status, ADHD symptoms, depressive symptoms, and anxiety, sleep problems accounted for a small but significant proportion of additional variance in the prediction of parent-reported sleepy/sluggish SCT. Difficulty waking showed the strongest associations with parent-reported SCT. There were no significant relationships found between parent-reported sleep difficulties and teacher-reported SCT.

CONCLUSIONS

Some elements of sluggishness and lethargy inherent to the SCT construct may be associated with sleep difficulties, even after accounting for ADHD and mood symptoms; however, these associations are not consistent across SCT subscales and sleep problem domains.

Longitudinal Correlates of Sluggish Cognitive Tempo and ADHD-Inattention Symptom Dimensions with Spanish Children

The objective was to examine the longitudinal correlates of sluggish cognitive tempo (SCT) and attention deficit/hyperactivity disorder (ADHD)-Inattention (IN) dimensions with mothers' and fathers' ratings of Spanish children. Mothers and fathers rated SCT, ADHD-IN, ADHD-hyperactivity/impulsivity (HI), oppositional defiant disorder (ODD), depression, academic impairment, and social impairment on 3 occasions (twice in first-grade year [6-week separation] and once in the second-grade year [12 months after the first assessment]) in Spanish children (758, 746, and 718 children at the 3 time-points with approximately 55% boys). The results showed that (a) higher levels of SCT from earlier assessments predicted higher levels of depression, academic impairment, and social impairment at Assessment 3 after controlling for ADHD-IN at earlier assessments; (b) higher levels of ADHD-IN from earlier assessments predicted higher levels of depression, academic impairment, and social impairment at Assessment 3 after controlling for SCT at earlier assessments; (c) higher levels of ADHD-IN from earlier assessments predicted higher levels of ADHD-HI and ODD at Assessment 3 after controlling for SCT from earlier assessments; and (d) higher levels of SCT from earlier assessments either showed no unique relationship with ADHD-HI and ODD or predicted lower levels of ADHD-HI and ODD at Assessment 3 after controlling for ADHD-IN from earlier assessments. Initial evidence is provided of SCT's unique longitudinal relationships with depression and academic/social impairment and different longitudinal relationships with ADHD-HI and ODD relative to ADHD-IN, thus adding to a growing body of research underscoring the importance of SCT as distinct from ADHD-IN.