The role of speed in ADHD-related working memory deficits: A time-based resource-sharing and diffusion model account

Differences in time perception in patients with obstructive sleep apnea

BACKGROUND

Obstructive sleep apnea (OSA) is a condition that occurs due to complete (apnea) and partial (hypopnea) obstruction in the upper airways during sleep. Hypoxia is one of the key factors contributing to the development of symptoms of obstructive sleep apnea and OSA-related diseases.

OBJECTIVE

The present study aimed to evaluate time perception differences between patients with OSA and healthy individuals, as well as among different OSA severity groups.

METHODS

Twenty severe OSA, twenty moderate OSA, twenty mild OSA patients, and twenty healthy volunteers without OSA were included in the study. Scales were administered to the participants. Time perception tests were administered to evaluate perceptual timing.

RESULTS

In the paced motor timing test, a difference was observed between the OSA ( +) group and the OSA (-) group. In the Time Estimation Test, a difference was observed between the OSA ( +) group and the OSA (-) group and their subgroups.

CONCLUSION

The internal clock works slower in the OSA ( +) group. When subgroups were compared based on the degree of OSA, the internal clock worked slower as we transitioned from the OSA (-) group to the severe OSA group. It is considered that as you move from the OSA (-) group to the severe OSA group, the switch between pacemaker and accumulator is disrupted due to the decrease in attention. Recurrent hypoxia observed in OSA may alter the perception of time by affecting attention.

EZ-CDM: Fast, simple, robust, and accurate estimation of circular diffusion model parameters

The investigation of cognitive processes that form the basis of decision-making in paradigms involving continuous outcomes has gained the interest of modeling researchers who aim to develop a dynamic decision theory that accounts for both speed and accuracy. One of the most important of these continuous models is the circular diffusion model (CDM, Smith. Psychological Review, 123(4), 425. 2016), which posits a noisy accumulation process mathematically described as a stochastic two-dimensional Wiener process inside a disk. Despite the considerable benefits of this model, its mathematical intricacy has limited its utilization among scholars. Here, we propose a straightforward and user-friendly method for estimating the CDM parameters and fitting the model to continuous-scale data using simple formulas that can be readily computed and do not require theoretical knowledge of model fitting or extensive programming. Notwithstanding its simplicity, we demonstrate that the aforementioned method performs with a level of accuracy that is comparable to that of the maximum likelihood estimation method. Furthermore, a robust version of the method is presented, which maintains its simplicity while exhibiting a high degree of resistance to contaminant responses. Additionally, we show that the approach is capable of reliably measuring the key parameters of the CDM, even when these values are subject to across-trial variability. Finally, we demonstrate the practical application of the method on experimental data. Specifically, an illustrative example is presented wherein the method is employed along with estimating the probability of guessing. It is hoped that the straightforward methodology presented here will, on the one hand, help narrow the divide between theoretical constructs and empirical observations on continuous response tasks and, on the other hand, inspire cognitive psychology researchers to shift their laboratory investigations towards continuous response paradigms.

A diffusion decision model analysis of the cognitive effects of neurofeedback for ADHD

OBJECTIVE

To examine cognitive effects of neurofeedback (NF) for attention-deficit hyperactivity disorder (ADHD) as a secondary outcome of a randomized clinical trial.

METHOD

In a double-blind randomized clinical trial (NCT02251743), 133 7-10-year olds with ADHD received either 38 sessions of NF (n = 78) or control treatment (n = 55) and performed an integrated visual and auditory continuous performance test at baseline, mid- and end-treatment. We used the diffusion decision model to decompose integrated visual and auditory continuous performance test performance at each assessment into cognitive components: efficiency of integrating stimulus information (v), context sensitivity (cv), response cautiousness (a), response bias (z/a), and nondecision time for perceptual encoding and response execution (Ter). Based on prior findings, we tested whether the components known to be deficient improved with NF and explored whether other cognitive components improved using linear mixed modeling.

RESULTS

Before NF, children with ADHD showed main deficits in integrating stimulus information (v), which led to less accurate and slower responses than healthy controls (p = .008). The NF group showed significantly more improvement in integrating auditory stimulus information (v) than control treatment (significant group-by-time-by-modality effect: p = .044).

CONCLUSIONS

NF seems to improve v, deficient in ADHD. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Slower Processing Speed in Autism Spectrum Disorder: A Meta-analytic Investigation of Time-Based Tasks

Autism spectrum disorder (ASD) is a complex neurodevelopmental condition affecting information processing across domains. The current meta-analysis investigated whether slower processing speed is associated with the ASD neurocognitive profile and whether findings hold across different time-based tasks and stimuli (social vs. nonsocial; linguistic vs. nonlinguistic). Mean RTs of ASD and age-matched neurotypical comparison groups (N = 893 ASD, 1063 neurotypical; mean age ASD group = 17 years) were compared across simple RT, choice RT, and interference control tasks (44 studies, 106 effects) using robust variance estimation meta-analysis. Simple RT tasks required participants to respond to individual stimuli, whereas choice RT tasks required forced-choice responses to two or more stimuli. Interference control tasks required a decision in the context of a distractor or priming stimulus; in an effort to minimize inhibitory demands, we extracted RTs only from baseline and congruent conditions of such tasks. All tasks required nonverbal (motor) responses. The overall effect-size estimate indicated significantly longer mean RTs in ASD groups (g = .35, 95% CI = .16; .54) than comparison groups. Task type moderated effects, with larger estimates drawn from simple RT tasks than interference control tasks. However, across all three task types, ASD groups exhibited significantly longer mean RTs than comparison groups. Stimulus type and age did not moderate effects. Generalized slowing may be a domain-general characteristic of ASD with potential consequences for social, language, and motor development. Assessing processing speed may inform development of interventions to support autistic individuals and their diverse cognitive profiles.

Preferential Choice to Exert Cognitive Effort in Children with ADHD: a Diffusion Modelling Account

Greater sensitivity to the cost of effortful engagement has long been implicated in the development of Attention Deficit Hyperactivity Disorder (ADHD). The current study evaluated preferential choice to engage in demanding tasks, and did so in combination with computational methods to interrogate the process of choice. Children aged 8-12 with (n = 49) and without (n = 36) ADHD were administered the cognitive effort discounting paradigm (COG-ED, adapted from Westbrook et al., 2013). Diffusion modelling was subsequently applied to the choice data to allow for a better description of the process of affective decision making. All children showed evidence of effort discounting, but, contrary to theoretical expectations, there was no evidence that children with ADHD judged effortful tasks to be lower in subjective value, or that they maintained a bias towards less effortful tasks. However, children with ADHD developed a much less differentiated mental representation of demand than their non-ADHD counterparts even though familiarity with and exposure to the experience of effort was similar between groups. Thus, despite theoretical arguments to the contrary, and colloquial use of motivational constructs to explain ADHD-related behavior, our findings strongly argue against the presence of greater sensitivity to costs of effort or reduced sensitivity to rewards as an explanatory mechanism. Instead, there appears to be a more global weakness in the metacognitive monitoring of demand, which is a critical precursor for cost-benefit analyses that underlie decisions to engage cognitive control.

Networks of Neuropsychological Functions in the Clinical Evaluation of Adult ADHD

This study applied network analysis to explore the relations between neuropsychological functions of individuals in the clinical evaluation of attention-deficit/hyperactivity disorder (ADHD) in adulthood. A total of 319 participants from an outpatient referral context, that is, 173 individuals with ADHD (ADHD group) and 146 individuals without ADHD (n-ADHD group), took part in this study and completed a comprehensive neuropsychological assessment. A denser network with stronger global connectivity was observed in the ADHD group compared to the n-ADHD group. The strongest connections were consistent in both networks, that is, the connections between selective attention and vigilance, and connections between processing speed, fluency, and flexibility. Further centrality estimation revealed attention-related variables to have the highest expected influence in both networks. The observed relationships between neuropsychological functions, and the high centrality of attention, may help identify neuropsychological profiles that are specific to ADHD and optimize neuropsychological assessment and treatment planning of individuals with cognitive impairment.

Transcranial random noise stimulation combined with cognitive training for treating ADHD: a randomized, sham-controlled clinical trial

Non-invasive brain stimulation has been suggested as a potential treatment for improving symptomology and cognitive deficits in Attention-Deficit/Hyperactivity Disorder (ADHD), the most common childhood neurodevelopmental disorder. Here, we examined whether a novel form of stimulation, high-frequency transcranial random noise stimulation (tRNS), applied with cognitive training (CT), may impact symptoms and neural oscillations in children with ADHD. We conducted a randomized, double-blind, sham-controlled trial in 23 unmedicated children with ADHD, who received either tRNS over the right inferior frontal gyrus (rIFG) and left dorsolateral prefrontal cortex (lDLPFC) or sham stimulation for 2 weeks, combined with CT. tRNS + CT yielded significant clinical improvements (reduced parent-reported ADHD rating-scale scores) following treatment, compared to the control intervention. These improvements did not change significantly at a 3-week follow-up. Moreover, resting state (RS)-EEG periodic beta bandwidth of the extracted peaks was reduced in the experimental compared to control group immediately following treatment, with further reduction at follow-up. A lower aperiodic exponent, which reflects a higher cortical excitation/inhibition (E/I) balance and has been related to cognitive improvement, was seen in the experimental compared to control group. This replicates previous tRNS findings in adults without ADHD but was significant only when using a directional hypothesis. The experimental group further exhibited longer sleep onset latencies and more wake-up times following treatment compared to the control group. No significant group differences were seen in executive functions, nor in reported adverse events. We conclude that tRNS + CT has a lasting clinical effect on ADHD symptoms and on beta activity. These results provide a preliminary direction towards a novel intervention in pediatric ADHD.

Processing Speed is Related to the General Psychopathology Factor in Youth

The relationship between the p factor and cognition in youth has largely focused on general cognition (IQ) and executive functions (EF). Another cognitive construct, processing speed (PS), is dissociable from IQ and EF, but has received less research attention despite being related to many different mental health symptoms. The present sample included 795 youth, ages 11-16 from the Colorado Learning Disabilities Research Center (CLDRC) sample. Confirmatory factor analyses tested multiple p factor models, with the primary model being a second-order, multi-reporter p factor. We then tested the correlation between the p factor and a latent PS factor. There was a significant, negative correlation between the p factor and PS (r(87) = -0.42, p < .001), indicating that slower processing speed is associated with higher general mental health symptoms. This association is stronger than previously reported associations with IQ or EF. This finding was robust across models that used different raters (youth and caregiver) and modeling approaches (second-order vs. bifactor). Our findings indicate that PS is related to general psychopathology symptoms. This research points to processing speed as an important transdiagnostic construct that warrants further exploration across development.

Hill L, Kline A, Stanley BH, Interian A. Improving the prospective prediction of a near-term suicide attempt in veterans at risk for suicide, using a go/no-go task

BACKGROUND

Neurocognitive testing may advance the goal of predicting near-term suicide risk. The current study examined whether performance on a Go/No-go (GNG) task, and computational modeling to extract latent cognitive variables, could enhance prediction of suicide attempts within next 90 days, among individuals at high-risk for suicide.

METHOD

136 Veterans at high-risk for suicide previously completed a computer-based GNG task requiring rapid responding (Go) to target stimuli, while withholding responses (No-go) to infrequent foil stimuli; behavioral variables included false alarms to foils (failure to inhibit) and missed responses to targets. We conducted a secondary analysis of these data, with outcomes defined as actual suicide attempt (ASA), other suicide-related event (OtherSE) such as interrupted/aborted attempt or preparatory behavior, or neither (noSE), within 90-days after GNG testing, to examine whether GNG variables could improve ASA prediction over standard clinical variables. A computational model (linear ballistic accumulator, LBA) was also applied, to elucidate cognitive mechanisms underlying group differences.

RESULTS

On GNG, increased miss rate selectively predicted ASA, while increased false alarm rate predicted OtherSE (without ASA) within the 90-day follow-up window. In LBA modeling, ASA (but not OtherSE) was associated with decreases in decisional efficiency to targets, suggesting differences in the evidence accumulation process were specifically associated with upcoming ASA.

CONCLUSIONS

These findings suggest that GNG may improve prediction of near-term suicide risk, with distinct behavioral patterns in those who will attempt suicide within the next 90 days. Computational modeling suggests qualitative differences in cognition in individuals at near-term risk of suicide attempt.

Cognitive functions and symptoms predicting later use of psychiatric services following mild traumatic brain injury in school-age

OBJECTIVE

To investigate whether neuropsychological test performance or presence of some specific injury symptoms at 1-3 months following pediatric mild traumatic brain injury (mTBI) can help to identify the children at risk for developing post-traumatic psychiatric symptoms.

METHODS

Data from 120 children and adolescents aged 7-15 years, treated at Turku University Hospital between 2010 and 2016 due to mTBI, and who had undergone neuropsychological evaluation at 1-3 months following injury, were enrolled from the hospital records. Neuropsychological test performancesand injury symptom reports were retrospectively retrieved from the patient files.

RESULTS

Slow information processing speed (p = 0.044), emotion regulation deficit (p = 0.014), impulsivity (p = 0.013), verbal processing difficulties (p = 0.042) and headache (p = 0.026) were independent predictors for having later contact in psychiatric care.

CONCLUSIONS

Neuropsychological examination containing measure of information processing speed, injury symptom interview, and parental questionnaires on behavioural issues of the child at 1-3 months following mTBI seems to be useful in detecting children with risk for post traumatic psychiatric symptoms. Targeted support and guidance for this group of children and adolescents and their families are recommended to prevent the development of an unfavorable psychosocial outcome.

A Comparative Study of Prison Inmates With and Without ADHD: Which Neuropsychological and Self-Report Measures are Most Effective in Detecting ADHD Within Correctional Services?

OBJECTIVE

In this study we aimed to investigate the screening and diagnostic properties of various self-report instruments to identify measures which most effectively detect ADHD in a correctional sample.

METHOD

The sample consisted of 193 male high security prisoners in Sweden. We investigated if measures of ADHD symptoms, executive functioning, impulsivity, estimated IQ and working memory could differentiate participants with ADHD from those with ASPD or no diagnosis.

RESULTS

Participants with ADHD obtained significantly higher total scores on all included measures. Although we found that some of the measures were more efficient in differentiating ADHD, mean values were generally elevated in the sample.

CONCLUSION

Results demonstrate the importance of investigating psychometric properties in relevant samples to assure a measurement's usefulness in different contexts, in this case a correctional setting, where the high influence of unspecific behavioral indicators in these measurements might negatively affect their validity.

Can children and adolescents with ADHD use attention to maintain verbal information in working memory?

Children and adolescents with attentional-deficit/hyperactivity disorder (ADHD) present deficits in working memory (WM), but accounts for this phenomenon are still lacking. In this study, we used two variations of a complex-span task to test whether a specific WM mechanism, attentional refreshing, causes these deficits. Attentional refreshing is a maintenance strategy based on the sequential switch of attention between maintaining and processing information in WM. Its use is evidenced by a decrease in recall performance proportional to the distraction of attention away from the memoranda. In this study, we designed two experiments requiring children and adolescents with ADHD symptoms to maintain sequences of letters for subsequent recall, while performing a distracting task. In Experiment 1, the distracting task consisted of reading digits aloud. In Experiment 2, it consisted in making spatial judgements. The pace of the distracting tasks was varied to manipulate the level of attentional distraction. We observed that recall in ADHD participants was higher in the distracting conditions that give attention more opportunity to refresh letters. Moreover, ADHD participants had a similar recall performance to their age-matched typically developing peers. This study shows first evidence that individuals with ADHD can use attention to maintain verbal information in WM and calls for more research to understand their WM development.

Mechanism-based groups of children with ADHD are associated with distinct domains of impairment

Person-oriented analyses are commonly used to identify subgroups of children with mental health conditions in the hopes that they will meaningfully inform the taxonomy, assessment, and treatment of psychological disorder. However, whether these data-driven groups are demonstrably better at predicting important aspects of adaptive functioning than standard DSM taxonomy has not been established. Using Attention-Deficit-Hyperactivity-Disorder (ADHD) as a model condition, we utilized dimensions of personality and cognitive ability to identify person-centered profiles of school-aged children (N=246) and evaluated the association of these profiles with critical areas of adaptive functioning. A single profile ("Conscientious") represented non-ADHD controls and was characterized by faster drift rate and higher executive functioning scores. Three profiles ("Disagreeable," "Negative Emotionality," and "Extraverted") were identified for children with ADHD. Drift rate, but not executive functioning, distinguished among ADHD profiles, which were also distinctly associated with comorbid externalizing and internalizing psychopathology, social skills, and academic achievement. In contrast, the Diagnostic and Statistical Manual (DSM) presentations were not informative and showed similar patterns of impairment across domains. Person-centered profiles of children with ADHD are associated with distinct adaptive functioning deficits and may be useful in informing clinical practice.

Ahead of the (ROC) Curve: A Statistical Approach to Utilizing Ex-Gaussian Parameters of Reaction Time in Diagnosing ADHD Across Three Developmental Periods

INTRODUCTION

Performance on executive function (EF) tasks is only modestly predictive of a diagnosis of Attention Deficit Hyperactivity Disorder (ADHD), despite the common assumption that EF deficits are ubiquitous to the disorder. The current study sought to determine whether ex-Gaussian parameters of simple reaction time are better able to discriminate between children and adults with and without ADHD, compared with traditional measures of inhibitory control.

METHODS

Receiver Operating Characteristic (ROC) analyses and the area under the curve (AUC) were used to examine the ability of performance on two commonly used tasks of inhibitory control (i.e. stop signal reaction time (SSRT) and go-no-go tasks) to predict ADHD status in preschool (N = 108), middle childhood (N = 309), and young adulthood (N = 133).

RESULTS

Across all samples, SSRT, go-no-go percentage of failed inhibits, and standard deviation of reaction (SDRT) time to "go" trials, all successfully discriminated between individuals with and without ADHD. Ex-Gaussian decomposition of the RT distribution indicated that both larger tau and larger sigma drove findings for SDRT. Contrary to predictions, traditional measures of inhibitory control were equal if not better predictors of ADHD status than ex-Gaussian parameters.

CONCLUSIONS

Findings support ongoing work to quantify the separate contributions of cognitive subprocesses that drive task performance, which in turn is critical to developing and improving process-based approaches in clinical assessment.

Event rate effects on children with attention-deficit/hyperactive disorder: Test predictions from the moderate brain arousal model and the neuro-energetics theory using the diffusion decision model

BACKGROUND

Converging evidence has found that the inhibitory control of children with attention-deficit/hyperactive disorder (ADHD) is context-dependent and particularly susceptible to the event rate. The Moderate Brain Arousal (MBA) model predicts a U-shaped curve between event rate and performance as a modulation of brain arousal. The neuroenergetics theory (NeT) proposes that a smaller event rate results in neuronal fatigue and subsequent descent performance. However, previous work applied the traditional one-dimensional index of performance, such as accuracy rate and response time, which might limit the exploration of the event rate effect on the specific underlying process.

AIMS

We used a diffusion decision model (DDM) to study the influence of event rate on inhibition control in children with ADHD and verified the explanation of the MBA model and the NeT.

METHODS AND PROCEDURES

The Stop Signal Task manipulated by four event rate conditions was conducted with 24 children with ADHD (mean age=8.5, males=16) and 29 typical developmental children (TDC) (mean age=9.0, males=12). DDM was applied to compare the differences in the DDM parameters across different event rates.

OUTCOMES AND RESULTS

Compared with TDC, children with ADHD had a smaller drift rate, longer non-decision time, and smaller boundary separation. Although the event rate had little influence on ADHD, the drift rate of the TDC was approximately linear with an increased event rate, and the Ter had a quadratic function relationship with the event rate.

CONCLUSIONS AND IMPLICATIONS

The event rate effect may influence children's performance through dual mechanisms. Neuronal energy supply could regulate information processing and brain arousal to regulate the activation of primary stimuli encoding and motor control. Insight into the multi-mechanism of ADHD cognition deficits would be helpful for clinicians in making objective diagnoses and effective targeted treatments.

Examining the Effect of Transcranial Electrical Stimulation and Cognitive Training on Processing Speed in Pediatric Attention Deficit Hyperactivity Disorder: A Pilot Study

Objective

Processing Speed (PS), the ability to perceive and react fast to stimuli in the environment, has been shown to be impaired in children with attention deficit hyperactivity disorder (ADHD). However, it is unclear whether PS can be improved following targeted treatments for ADHD. Here we examined potential changes in PS following application of transcranial electric stimulation (tES) combined with cognitive training (CT) in children with ADHD. Specifically, we examined changes in PS in the presence of different conditions of mental fatigue.

Methods

We used a randomized double-blind active-controlled crossover study of 19 unmedicated children with ADHD. Participants received either anodal transcranial direct current stimulation (tDCS) over the left dorsolateral prefrontal cortex (dlPFC) or transcranial random noise stimulation (tRNS), while completing CT, and the administration order was counterbalanced. PS was assessed before and after treatment using the MOXO-CPT, which measures PS in the presence of various conditions of mental fatigue and cognitive load.

Results

tRNS combined with CT yielded larger improvements in PS compared to tDCS combined with CT, mainly under condition of increased mental fatigue. Further improvements in PS were also seen in a 1-week follow up testing.

Conclusion

This study provides initial support for the efficacy of tRNS combined with CT in improving PS in the presence of mental fatigue in pediatric ADHD.

Behavioural and neural indices of perceptual decision-making in autistic children during visual motion tasks

Many studies report atypical responses to sensory information in autistic individuals, yet it is not clear which stages of processing are affected, with little consideration given to decision-making processes. We combined diffusion modelling with high-density EEG to identify which processing stages differ between 50 autistic and 50 typically developing children aged 6-14 years during two visual motion tasks. Our pre-registered hypotheses were that autistic children would show task-dependent differences in sensory evidence accumulation, alongside a more cautious decision-making style and longer non-decision time across tasks. We tested these hypotheses using hierarchical Bayesian diffusion models with a rigorous blind modelling approach, finding no conclusive evidence for our hypotheses. Using a data-driven method, we identified a response-locked centro-parietal component previously linked to the decision-making process. The build-up in this component did not consistently relate to evidence accumulation in autistic children. This suggests that the relationship between the EEG measure and diffusion-modelling is not straightforward in autistic children. Compared to a related study of children with dyslexia, motion processing differences appear less pronounced in autistic children. Exploratory analyses also suggest weak evidence that ADHD symptoms moderate perceptual decision-making in autistic children.

Task-general efficiency of evidence accumulation as a computationally-defined neurocognitive trait: Implications for clinical neuroscience

Quantifying individual differences in higher-order cognitive functions is a foundational area of cognitive science that also has profound implications for research on psychopathology. For the last two decades, the dominant approach in these fields has been to attempt to fractionate higher-order functions into hypothesized components (e.g., "inhibition", "updating") through a combination of experimental manipulation and factor analysis. However, the putative constructs obtained through this paradigm have recently been met with substantial criticism on both theoretical and empirical grounds. Concurrently, an alternative approach has emerged focusing on parameters of formal computational models of cognition that have been developed in mathematical psychology. These models posit biologically plausible and experimentally validated explanations of the data-generating process for cognitive tasks, allowing them to be used to measure the latent mechanisms that underlie performance. One of the primary insights provided by recent applications of such models is that individual and clinical differences in performance on a wide variety of cognitive tasks, ranging from simple choice tasks to complex executive paradigms, are largely driven by efficiency of evidence accumulation (EEA), a computational mechanism defined by sequential sampling models. This review assembles evidence for the hypothesis that EEA is a central individual difference dimension that explains neurocognitive deficits in multiple clinical disorders and identifies ways in which in this insight can advance clinical neuroscience research. We propose that recognition of EEA as a major driver of neurocognitive differences will allow the field to make clearer inferences about cognitive abnormalities in psychopathology and their links to neurobiology.

Transcranial direct current stimulation (tDCS) alters the pattern of information processing in children with ADHD: Evidence from drift diffusion modeling

OBJECTIVE

Performance accuracy and reaction time in cognitive tasks are routinely used to evaluate the efficacy of tDCS to affect cognitive task performance. tDCS alters the excitability of targeted brain areas and thereby alters performance of cognitive tasks. The drift diffusion model (DDM) provides some additional measures to explore information processing style, such as (non)decision time, bias for decision, and speed of information processing. DDM parameters are informative for the study of cognitive impairments in children with ADHD. In the present study, we aimed to evaluate the impact of tDCS on cognitive performance via DDM measures.

METHODS

This study conducted DDM modeling and reanalysis of two exploratory, single-blinded, within-subject design experiments, which were published earlier. In the first experiment, twenty- four children with ADHD performed a Go/ No- Go task during anodal or sham tDCS over the right dlPFC. In the second experiment, twenty- five children with ADHD performed the 1- back working memory task during anodal or sham tDCS over the left dlPFC. We reanalyzed the data after DDM modeling.

RESULTS

The conventional performance measures revealed no significant effect of tDCS on No- Go accuracy in the first experiment and 1-back accuracy in the second experiment. The 1-back reaction time and speed-accuracy tradeoff were however improved under the real stimulation condition. The DDM measures identified increased No-Go- bias and decision time with respect to inhibitory control, and an increased threshold and amount of information required for response in the 1- back test.

CONCLUSION

In children with ADHD, anodal tDCS over the right dlPFC induces more conservative and less impulsive decisions. Furthermore, anodal tDCS over the left dlPFC enhanced efficacy of working memory performance with respect to agility and capacity. The experimental results show that drift diffusion modeling is useful for evaluation of the impact of tDCS on the style of information processing.

Preregistration in diverse contexts: a preregistration template for the application of cognitive models

In recent years, open science practices have become increasingly popular in psychology and related sciences. These practices aim to increase rigour and transparency in science as a potential response to the challenges posed by the replication crisis. Many of these reforms-including the increasingly used preregistration-have been designed for purely experimental work that tests straightforward hypotheses with standard inferential statistical analyses, such as assessing whether an experimental manipulation has an effect on a variable of interest. But psychology is a diverse field of research. The somewhat narrow focus of the prevalent discussions surrounding and templates for preregistration has led to debates on how appropriate these reforms are for areas of research with more diverse hypotheses and more intricate methods of analysis, such as cognitive modelling research within mathematical psychology. Our article attempts to bridge the gap between open science and mathematical psychology, focusing on the type of cognitive modelling that Crüwell et al. (Crüwell S, Stefan AM, Evans NJ. 2019 Robust standards in cognitive science. Comput. Brain Behav. 2, 255-265) labelled model application, where researchers apply a cognitive model as a measurement tool to test hypotheses about parameters of the cognitive model. Specifically, we (i) discuss several potential researcher degrees of freedom within model application, (ii) provide the first preregistration template for model application and (iii) provide an example of a preregistered model application using our preregistration template. More broadly, we hope that our discussions and concrete proposals constructively advance the mostly abstract current debate surrounding preregistration in cognitive modelling, and provide a guide for how preregistration templates may be developed in other diverse or intricate research contexts.

Basic and complex cognitive functions in Adult ADHD

Background

Many clinical studies reported deficits in basic and complex cognitive functions in adults with Attention-Deficit/Hyperactivity Disorder (ADHD). However, the extent in which deficits in basic functions (i.e., processing speed and distractibility) contribute to complex cognitive impairments (i.e., working memory, planning, cognitive flexibility, memory functions) in adults with ADHD is not well-studied. So far, literature show only one study, revealing that basic functions explain 27–74% of executive dysfunctions. Yet, the authors reported that findings could be affected by the selection of neuropsychological tests. The goal of the present research is to replicate such a finding using a different sample and a different set of neuropsychological tests.

Methods

Forty-eight adult patients with ADHD were compared with 48 healthy controls in basic cognitive functions, namely processing speed and distractibility and more complex cognitive functions, namely selective attention, cognitive flexibility, planning, working memory, verbal fluency, and verbal memory. Basic and complex cognitive functions were assessed using the Vigilance and Sustained Attention, Selective Attention, N-Back, Tower of London, Trail Making Test, Word Fluency, and Verbal Learning and Memory.

Results and conclusion

Logistic regression analyses showed that impairments in complex cognitive functions explained 25% of the variance in ADHD diagnosis. The explained variance dropped from 25% to 9% after considering basic functions of processing speed and distractibility. This 64% reduction highlights the importance of basic functions for impairments in complex functions in patients with ADHD.

A New Spin on Spatial Cognition in ADHD: A Diffusion Model Decomposition of Mental Rotation

OBJECTIVES

Multiple studies have found evidence of task non-specific slow drift rate in ADHD, and slow drift rate has rapidly become one of the most visible cognitive hallmarks of the disorder. In this study, we use the diffusion model to determine whether atypicalities in visuospatial cognitive processing exist independently of slow drift rate.

METHODS

Eight- to twelve-year-old children with (n = 207) and without ADHD (n = 99) completed a 144-trial mental rotation task.

RESULTS

Performance of children with ADHD was less accurate and more variable than non-ADHD controls, but there were no group differences in mean response time. Drift rate was slower, but nondecision time was faster for children with ADHD. A Rotation × ADHD interaction for boundary separation was also found in which children with ADHD did not strategically adjust their response thresholds to the same degree as non-ADHD controls. However, the Rotation × ADHD interaction was not significant for nondecision time, which would have been the primary indicator of a specific deficit in mental rotation per se.

CONCLUSIONS

Poorer performance on the mental rotation task was due to slow rate of evidence accumulation, as well as relative inflexibility in adjusting boundary separation, but not to impaired visuospatial processing specifically. We discuss the implications of these findings for future cognitive research in ADHD.

Clinical presentations of attention-deficit/hyperactivity disorder (ADHD) in children and adolescents: comparison of neurocognitive performance

This study aimed to compare performance in working memory (WM), processing speed (PRS), and attention measures in children and adolescents with typical development (TD) and with Attention deficit hyperactivity disorder (inattentive [ADHD-I] or combined [ADHD-C]) presentations, and to determine the predictive ability of the measures mentioned to discriminate between ADHD presentations and TD. 260 children and adolescents, 138 with ADHD (70 ADHD-I and 68 ADHD-C) and 122 TD in two age cohorts (8-12 years; 13-16 years), were assessed with WM and PRS indexes of Wechsler Intelligence Scale for Children (WISC-IV) and the d2 attention test. Significant differences between ADHD and TD groups in the WISC-IV GAI scores were found in children but not in adolescents. Children and adolescents with both ADHD presentations performed poorly on the PRS index, while on the WM index only children exhibited difficulties. In the attention test, children with ADHD-C showed more impulsivity and more difficulties for processing speed, concentration and accuracy than ADHD-I and TD. In addition, both ADHD presentations had higher inattention scores than TD. ADHD adolescents performed worse than TD in processing speed, concentration and accuracy. ADHD groups showed more impulsivity and inattention than TD. Digit Span and Symbol Search (WISC-IV) and processing speed and accuracy (d2) successfully classified ADHD and TD in children, but in adolescents, only coding (WISC-IV) and accuracy (d2) successfully classified ADHD presentations and TD. The WISC-IV and d2 yield neuropsychological profiles which reflect age-related cognitive changes and may allow the adaptation of more tailored early interventions for ADHD.

Neural basis of working memory in ADHD: Load versus complexity

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Working memory (WM).

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Load versus Complexity.

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ADHD.

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FMRI.

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Working Memory Striatum and Cerebellum.

Working memory (WM) deficits are key in attention deficit hyperactivity disorder (ADHD). Nevertheless, WM is not universally impaired in ADHD. Additionally, the neural basis for WM deficits in ADHD has not been conclusively established, with regions including the prefrontal cortex, cerebellum, and caudate being implicated. These contradictions may be related to conceptualizations of WM capacity, such as load (amount of information) versus operational-complexity (maintenance-recall or manipulation). For instance, relative to neurotypical (NT) individuals, complex WM operations could be impaired in ADHD, while simpler operations are spared. Alternatively, all operations may be impaired at higher loads. Here, we compared the impact of these two components of WM capacity: load and operational-complexity, between ADHD and NT, behaviorally and neurally. We hypothesized that the impact of WM load would be greater in ADHD, and the neural activation would be altered. Participants (age-range 12–23 years; 50 ADHD (18 females); 82 NT (41 females)) recalled three or four objects (load) in forward or backward order (operational-complexity) during functional magnetic resonance imaging scanning. The effects of diagnosis and task were compared on performance and neural engagement. Behaviorally, we found significant interactions between diagnosis and load, and between diagnosis, load, and complexity. Neurally, we found an interaction between diagnosis and load in the right striatum, and between diagnosis and complexity in the right cerebellum and left occipital gyrus. The ADHD group displayed hypo-activation compared to NT group during higher load and greater complexity. This informs mechanisms of functional problems related to WM in adolescents and young adults with ADHD (e.g., academic performance) and remedial interventions (e.g., WM-training).

Slow drift rate predicts ADHD symptomology over and above executive dysfunction

Slow drift rate has become one of the most salient cognitive deficits among children with ADHD, and has repeatedly been found to explain slow, variable, and error-prone performance on tasks of executive functioning (EF). The present study applies the diffusion model to determine whether slow drift rate better predicts parent and teacher ratings of ADHD than standard EF metrics. 201 children aged 8-12 completed two tests of speeded decision-making analyzed with the diffusion model and two traditionally scored tests of EF. Latent EF and drift rate factors each independently predicted the general ADHD factor in a bifactor model of ADHD, with poor EF and slow drift rate associated with greater ADHD symptomology. When both EF and drift rate were entered into the model, slow drift rate (but not EF) continued to predict elevated symptomology. These findings suggest that using drift rate to index task performance improves upon conventional approaches to measuring and conceptualizing cognitive dysfunction in ADHD. Implications for future cognitive research in ADHD are discussed.

Aiding diagnosis of childhood attention-deficit/hyperactivity disorder of the inattentive presentation: Discriminant function analysis of multi-domain measures including EEG

INTRODUCTION

We developed a neurocognitive assessment tool (NCAT) in consultation with mental health professionals working with children with AD/HD as a diagnostic aid and screening tool. This study examines the predictive utility of NCAT in the classification of children with AD/HD Inattentive presentation.

METHOD

Fifty three children with AD/HD Inattentive presentation and 161 typically-developing children completed an NCAT assessment. Discriminant function analyses examined group membership prediction for separate components of NCAT and for the components combined.

RESULTS

The combined model correctly classified 93.4 % of participants, with 91.4 % sensitivity and 93.9 % specificity. Contributions to classification were from SNAP-IV, psychological needs satisfaction, self-regulation, executive function performance, and EEG. The combined model resulted in a 9.3 % increase in specificity and 5.9 % increase in sensitivity compared to SNAP-IV alone.

CONCLUSIONS

NCAT provides good discrimination between children with and without AD/HD of the Inattentive presentation, and further investigation including other subtypes and comorbidities is warranted.

The arrow of time: Advancing insights into action control from the arrow version of the Eriksen flanker task

Since its introduction by B. A. Eriksen and C. W. Eriksen (Perception & Psychophysics, 16, 143-49, 1974), the flanker task has emerged as one of the most important experimental tasks in the history of cognitive psychology. The impact of a seemingly simple task design involving a target stimulus flanked on each side by a few task-irrelevant stimuli is astounding. It has inspired research across the fields of cognitive neuroscience, psychophysiology, neurology, psychiatry, and sports science. In our tribute to Charles W. ("Erik") Eriksen, we (1) review the seminal papers originating from his lab in the 1970s that launched the paradigmatic task and laid the foundation for studies of action control, (2) describe the inception of the arrow version of the Eriksen flanker task, (3) articulate the conceptual and neural models of action control that emerged from studies of the arrows flanker task, and (4) illustrate the influential role of the arrows flanker task in disclosing developmental trends in action control, fundamental deficits in action control due to neuropsychiatric disorders, and enhanced action control among elite athletes.

Differentiating depression and ADHD without depression in adults with processing-speed measures

OBJECTIVE

We evaluated processing-speed and shift-cost measures in adults with depression or attention-deficit hyperactivity disorder (ADHD) and monitored the effects of treatment. We hypothesised that cognitive-speed and shift-cost measures might differentiate diagnostic groups.

METHODS

Colour, form, and colour-form stimuli were used to measure naming times. The shift costs were calculated as colour-form-naming time minus the sum of colour- and form-naming times. Measurements were done at baseline and end point for 42 adults with depression and 42 with ADHD without depression. Patients with depression were treated with transcranial pulsed electromagnetic fields and patients with ADHD with methylphenidate immediate release.

RESULTS

During depression treatment, reductions in naming times were recorded weekly. One-way analysis of variance indicated statistical between-group differences, with effect sizes in the medium range for form and colour-form. In both groups, naming times were longer before than after treatment. For the ADHD group, shift costs exceeded the average-normal range at baseline but were in the average-normal range after stabilisation with stimulant medication. For the depression group, shift costs were in the average-normal range at baseline and after treatment. Baseline colour-form-naming times predicted reductions in naming times for both groups, with the largest effect size and index of forecasting efficiency for the ADHD group.

CONCLUSIONS

The cognitive-processing-speed (colour-form) and shift-cost measures before treatment proved most sensitive in differentiating patients with depression and ADHD. Reductions in naming times for the depression group were suggested to reflect improved psychomotor skills rather than improved cognitive control.

A comparison of local-global visuospatial processing in autism spectrum disorder, nonverbal learning disability, ADHD and typical development

BACKGROUND

Research on visuospatial functioning has revealed cognitive challenges for children with autism spectrum disorder (ASD), nonverbal learning disability (NLD) and attention deficit hyperactivity disorder (ADHD). These disorders are characterized by some overlapping symptoms, making their diagnosis a challenge.

AIMS

The study aims to clarify the role of visuospatial abilities in their neuropsychological profiles by investigating different visuospatial domains and their interplay with the local-global processing.

METHOD AND PROCEDURES

Participants (N = 150) with ASD, NLD, or ADHD were compared with typically-developing (TD) children on visuospatial processing speed, visuo-perceptual abilities, visuo-constructive abilities, and visuospatial working memory. Generalized mixed-effects models were performed and receiver operating characteristic curves were estimated to express the usefulness of a local-global processing index in discriminating groups.

OUTCOMES AND RESULTS

The NLD group was impaired in all domains; children with ADHD revealed a heterogeneous profile, with greater impairments in visuospatial processing speed; ASD and TD groups were comparable. The local-global processing index had predictive power in discriminating among groups in visuo-constructive task.

CONCLUSIONS AND IMPLICATIONS

The study of visuospatial abilities of children with ASD, NLD and ADHD might help to understand strengths and weaknesses in their neuropsychological profile and to differentiate between them. Clinical implications of these findings are discussed.

Cognitive Modeling Informs Interpretation of Go/No-Go Task-Related Neural Activations and Their Links to Externalizing Psychopathology

BACKGROUND

Individuals with attention-deficit/hyperactivity disorder and other externalizing psychopathologies tend to display poor behavioral performance on the go/no-go task, which is thought to reflect deficits in inhibitory control. However, clinical neuroimaging studies using this task have yielded conflicting results, raising basic questions about what the task measures and which aspects of the task relate to clinical outcomes. We used computational modeling to provide a clearer understanding of how neural activations from this task relate to the cognitive mechanisms that underlie performance and to probe the implications of these relationships for clinical research.

METHODS

A total of 143 young adults (8-21 years of age) performed the go/no-go task during functional magnetic resonance imaging scanning. We used the diffusion decision model (DDM), a cognitive modeling approach, to quantify distinct neurocognitive processes that underlie go/no-go performance. We then assessed correlations between DDM parameters and brain activation from standard go/no-go contrasts and assessed relationships of DDM parameters and associated neural measures with clinical ratings.

RESULTS

Right-lateralized prefrontal activations on correct inhibition trials, which are generally assumed to isolate neural processes involved in inhibition, were unrelated to DDM parameters (and other performance indices). However, responses to failed inhibitions in brain regions associated with error monitoring were strongly related to more efficient task performance and correlated with externalizing behavior and attention-deficit/hyperactivity disorder symptoms.

CONCLUSIONS

Our findings cast doubt on conventional interpretations of go/no-go task-related activations as reflecting the neural basis of inhibitory functioning. We instead found evidence that error-related contrasts provide clinically relevant information about neural systems involved in monitoring and optimizing the efficiency of cognitive performance.

A diffusion model analysis of sustained attention in children with attention deficit hyperactivity disorder

OBJECTIVE

Whether children with attention deficit hyperactivity disorder (ADHD) have deficits in sustained attention remains unresolved due to the ongoing use of cognitive paradigms that are not optimized for studying vigilance and the fact that relatively few studies report performance over time.

METHOD

In three independent samples of school-age children with (total N = 128) and without ADHD (total N = 59), we manipulated event rate, difficulty of discrimination, and use signal detection (SDT) and diffusion models (DM) to evaluate the cause of the vigilance decrement during a continuous performance task.

RESULTS

For both groups of children, a bias toward "no-go" over time (as indexed by the SDT parameter B″ and the DM parameter z/a) was responsible for generating the vigilance decrement. However, among children with ADHD, the rate at which information accumulated to make a no-go decision (vNoGo) also increased with time on task, representing a possible secondary mechanism that biases children against engagement. At all time points, children with ADHD demonstrated reduced sensitivity to discriminate targets from nontargets.

CONCLUSION

Children with ADHD are particularly sensitive to the cost of task engagement, but nonspecific slower drift rate may ultimately provide a better conceptualization of the cognitive atypicalities commonly observed in that group. Results are interpreted in the context of updated conceptualizations of sustained attention and vigilance. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Investigative interviewing of youth with ADHD - recommendations for detective training

Attention deficit hyperactivity disorder (ADHD) in youth can lead to a trajectory of early and repeated contact with the criminal justice system (CJS), where such youth face significant challenges due to the nature of their diagnosis and the lack of specialized detective training in this area. This article reviews Australian detectives' perceptions regarding contact with ADHD-affected youth, ongoing contact of such youth with the CJS, and the impact of ADHD on interviewing time efficiency and quality of information gathered. It explores detectives' perceived impact of ADHD on components of the Cognitive Interview (CI). It overviews detectives' perceptions regarding their own skill/ability, training availability and future training preferences regarding the interviewing of ADHD-affected youth. The authors highlight best practice in specialized detective training, as well as in working with ADHD-affected youth. Recommendations are made regarding the design features of a potential specialized training programme for detectives interviewing ADHD-affected youth.

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).

Working memory and information processing in ADHD: Evidence for directionality of effects

OBJECTIVE

Children with ADHD demonstrate impaired performance on a wide range of neuropsychological tests. It is unclear, however, whether ADHD is associated with many neurocognitive deficits or whether a small number of impairment(s) broadly influence test performance. The current study tests competing model predictions regarding two candidate causal mechanisms in ADHD: information processing speed and working memory.

METHOD

A well-characterized sample of 86 children (M_age = 10.52, SD_age = 1.54; 34 girls; 64% Caucasian/Non-Hispanic) with ADHD (n = 45) and without ADHD (n = 41) completed eight fully crossed experimental tasks that systematically manipulated working memory (BF₁₀ = 1.80 × 10⁹³) and information processing speed (drift rate; BF₁₀ = 7.61 × 10⁶).

RESULTS

Bayesian mixed-model ANOVAs indicated that increasing working memory demands produced significant reductions in information processing speed (drift rate; BF₁₀ = 5.82 × 10⁹⁶). In contrast, experimentally reducing children's information processing speed did not significantly change their working memory performance (BF₁₀ = 1.31). ADHD status interacted with the working memory manipulation, such that the ADHD and non-ADHD groups showed equivalently high accuracy under the encoding-only conditions (BF₀₁ = 3.45) but differed significantly under high working memory conditions (encoding + recall; BF₁₀ = 19.58). Importantly, however, ADHD status failed to interact with (a) the working memory manipulation to differentially affect information processing speed and (b) the information processing speed manipulation to differentially affect working memory performance (all BF₀₁ > 4.25).

CONCLUSIONS

These findings indicate that top-down executive control exerts significant effects on children's ability to quickly process information, but that working memory deficits and slowed information processing speed appear to be relatively independent impairments in ADHD. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Basic processes as foundations of cognitive impairment in adult ADHD

Attention deficit hyperactivity disorder (ADHD) in adulthood is associated with impairment of multiple aspects of cognition which adversely affect the individual's everyday functioning. However, little is known about how these impairments are intertwined. This study explores whether impairments in basic processes (processing speed and distractibility) in adults with ADHD explain impairments in higher order functions, namely executive functions, memory, and complex attention. Furthermore, it is explored whether pharmacological treatment with methylphenidate (MPH) affects basic processes and higher order functions. A between-subjects design compared patients with ADHD without stimulant drug treatment (N = 55) and patients with ADHD treated with MPH (N = 31) with a healthy control group (N = 80). A neuropsychological test battery assessing basic processes and higher order functions was administered. Hierarchical logistic regression analyses were performed to evaluate the contribution of basic processes to impairments in higher order functions. Patients with ADHD not treated with MPH showed impairments in basic processes and higher order functions compared to controls. The impairments in basic processes explained 41-43% of impairments in executive functions, 27-29% in memory, and 56-74% in complex attention. In patients with ADHD treated with MPH, basic processes were not impaired and did not contribute significantly to impairments of higher order functions. Basic processes may constitute part of the foundation of cognitive impairments in adult ADHD. MPH may improve cognitive performance, presumably through improving basic processes. Applying this information could optimize neuropsychological assessments and inform treatment strategies by targeting basic processes.

Cognitive Modeling Suggests That Attentional Failures Drive Longer Stop-Signal Reaction Time Estimates in Attention Deficit/Hyperactivity Disorder

Mean stop-signal reaction time (SSRT) is frequently employed as a measure of response inhibition in cognitive neuroscience research on ADHD. However, this measurement model is limited by two factors which may bias SSRT estimation in this population: 1) excessive skew in "go" RT distributions, and 2) trigger failures, or instances in which individuals fail to trigger an inhibition process in response to the "stop" signal. We use a Bayesian parametric approach, which allows unbiased estimation of the shape of entire SSRT distributions and the probability of trigger failures, to clarify mechanisms of stop-signal task deficits in ADHD. Children with ADHD displayed greater positive skew than their peers in both "go" RT and SSRT distributions. However, they also displayed more frequent trigger failures, which appeared to drive ADHD-related stopping difficulties. Results suggest that stop-signal task performance in ADHD reflects impairments in early attentional processes, rather than inefficiency in the stop process.

Inhibitory Control and Information Processing in ADHD: Comparing the Dual Task and Performance Adjustment Hypotheses

Inhibition is a key neurocognitive domain in ADHD that is commonly assessed with the stop-signal task. The stop-signal involves both "go" and "stop" trials; previous research indicates that response times are reliably slower to "go" trials during tasks with vs. without intermittent "stop" trials. However, it is unclear whether this pattern reflects deliberate slowing to maximize inhibitory success (performance adjustment hypothesis) and/or disrupted bottom-up information processing due to increased cognitive demands (dual-task hypothesis). Given the centrality of "go" responding for estimating children's inhibitory speed, finding that children with ADHD slow differently -or for different reasons- has the potential to inform cognitive and self-regulatory theories of ADHD. The current study used a carefully-controlled experimental design to assess the mechanisms underlying stop signal-related slowing in ADHD. Children ages 8-13 with (n = 81) and without ADHD (n = 63) completed the stop-signal task and a control task that differed only in the presence/absence of "stop" trials. Using drift-diffusion modeling, Bayesian repeated-measures ANOVAs revealed a pattern consistent with the performance adjustment hypothesis, such that children adopted more cautious response strategies (BF10 = 6221.78; d = 0.38) but did not show changes in processing speed (BF01 = 3.08; d = 0.12) or encoding/motor speed (BF01 = 5.73; d = 0.07) when inhibition demands were introduced. Importantly, the ADHD/Non-ADHD groups showed equivalent effects of intermittent "stop" trials (BF01 = 4.30-5.56). These findings suggest intact self-regulation/performance monitoring in the context of adapting to increased inhibitory demands in ADHD, which has important implications for the continued isolation of potential mechanisms associated with ADHD symptoms and impairment.

Clinical Implications of the Perception of Time in Attention Deficit Hyperactivity Disorder (ADHD): A Review

Attention deficit hyperactivity disorder (ADHD) is a lifelong neurodevelopmental disorder that can affect many areas of the daily life of individuals and is associated with poor health outcomes and with debilitating deficits in executive function. Recently, increasing numbers of research studies have begun to investigate the associations between neural and behavioral manifestations of ADHD. This review summarizes recent research on the perception of time in ADHD and proposes that this symptom is a possible diagnostic characteristic. Controlled studies on time perception have compared individuals with ADHD with typically developing controls (TDCs) and have used methods that include the Zimbardo Time Perspective Inventory (ZTPI). Practical approaches to time perception and its evaluation have shown that individuals with ADHD have difficulties in time estimation and discrimination activities as well as having the feeling that time is passing by without them being able to complete tasks accurately and well. Although ADHD has been associated with neurologic abnormalities in the mesolimbic and dopaminergic systems, recent studies have found that when individuals with ADHD are treated medically, their perception of time tends to normalize. The relationship between ADHD and the perception of time requires greater attention. Further studies on time perception in ADHD with other abnormalities, including executive function, might be approaches that refine the classification and diagnosis of ADHD and should include studies on its varied presentation in different age groups.

A diffusion-model analysis of timing deficits among children with ADHD

OBJECTIVE

Deficits in the ability to perceive time have been proposed as an etiologic mechanism in the development of the cognitive and behavioral characteristics associated with ADHD. However, previous studies testing the presence of timing deficits have produced idiosyncratic results. This is in large part due to the underutilization of insights from basic timing research, and from the inherent difficulty that arises when a single index of performance (i.e., reaction time [RT] or accuracy) is used to index the health of what is essentially a multiple-component process. The current article utilizes a diffusion model approach to isolate the component processes involved in timing (i.e., internal clock speed, decision-making speed, speed/accuracy trade-off strategies, and nondecision time) using a well-validated timing task.

METHOD

Fifty children with ADHD and 32 non-ADHD controls aged 8-12 completed a temporal bisection procedure.

RESULTS

Diffusion model parameters indicated that both the internal clock and decision-making speeds were slower among children with ADHD. However, the strength of evidence for slowed decision making far outweighed evidence for a slower internal clock.

CONCLUSIONS

Slower evidence accumulation during decision making is domain-general deficit in ADHD. Such slowing is consistent with adaptive-gain theories, which posit that a suboptimal ratio of neural signal-to-noise is characteristic of children with ADHD. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

The importance of impulsivity and attention switching deficits in perpetrators convicted for intimate partner violence

It has been stated that Attention deficit hyperactivity disorder (ADHD) increases the likelihood of risky behavior such as intimate partner violence (IPV), but the cognitive mechanisms that facilitate or underlie these types of behavior remain unexplained. In this regard, several authors have established that impulsivity and inattentive symptoms might affect basic processes such as emotional decoding and set-shifting abilities, which are important processes for emotional and behavioral regulation. Hence, these symptoms entail a reduction in sensitivity to key contextual stimuli. Accordingly, the main aim of this study was to examine the involvement of impulsivity (assessed by self-reports) and attention switching impairments (assessed with the Attention Switching Task; AST), as well as the associations between these cognitive processes in facial emotion decoding (assessed by the eyes test) and cognitive flexibility impairments (measured by the Wisconsin Card Sorting Test, WCST) in a sample of IPV perpetrators (n = 89; mean age = 40) and a control group matched on socio-demographic characteristics (n = 39; mean age = 41). IPV perpetrators had higher trait impulsivity and greater attention switching costs than controls. Moreover, differences were also found between groups in facial expression decoding and WCST performance, with IPV perpetrators showing lower Eyes Test and WCST scores. Mainly, we observed that the ability to recognize facial expressions was poorer when individuals showed high impulsivity in both groups, but this association was only explained by deficits in attention switching in IPV perpetrators. Our research reinforces the importance of impulsivity and inattentive symptoms as targets for specific cognitive rehabilitation interventions designed to prevent the long-term IPV risk of recidivism.

Police perceptions of the impact that ADHD has on conducting cognitive interviews with youth

Attention deficit hyperactivity disorder (ADHD) in youth witnesses, victims and suspects can significantly impact the investigative interviewing process. In this study, 102 Child Protection Investigation Unit (CPIU) detectives were asked to read four vignettes of adolescents being interviewed by police, two as witnesses and two as suspects, in which one witness and one suspect display ADHD-type behaviour. The detectives rated the degree to which the behaviour in each vignette would impact the interviewer's ability to use the 10 key components of the cognitive interview (CI). They perceived ADHD-type interviewee behaviour as significantly hampering the use of all 10 CI components. There is also a significant difference between the detectives' rated severity of each CI component; they rated Encourage Concentration, Mentally Recreate and Change Order as exerting the strongest impact on the interview process. Implications for police perceptions of training options, needs and preferences regarding interviewing youth with ADHD are discussed.

A cognitive model-based approach to testing mechanistic explanations for neuropsychological decrements during tobacco abstinence

RATIONALE

Cigarette smokers often experience cognitive decrements during abstinence from tobacco, and these decrements may have clinical relevance in the context of smoking cessation interventions. However, limitations of the behavioral summary statistics used to measure cognitive effects of abstinence, response times (RT) and accuracy rates, may restrict the field's ability to identify robust abstinence effects on task performance and test mechanistic hypotheses about the etiology of these cognitive changes.

OBJECTIVES

The current study explored whether a measurement approach based on mathematical models of cognition, which make the cognitive mechanisms necessary to perform choice RT tasks explicit, would be able to address these limitations.

METHODS

The linear ballistic accumulator model (LBA: Brown and Heathcote, Cogn Psychol 57(3):153-178, 2008) was fit to an existing data set from a study that evaluated the impact of overnight abstinence on flanker task performance.

RESULTS

The model-based analysis provided evidence that smokers' rates of mind wandering increased during abstinence, and was able to index this effect while controlling for participants' strategy changes that were related to the specific experimental paradigm used.

CONCLUSION

Mind wandering is a putative explanation for cognitive withdrawal symptoms during smoking cessation and may be indexed using the LBA. More broadly, the use of formal model-based analyses in future research on this topic has the potential to allow for strong and specific tests of mechanistic explanations for these symptoms.

Testing formal predictions of neuroscientific theories of ADHD with a cognitive model-based approach

Neuroscientific theories of attention-deficit/hyperactivity disorder (ADHD) alternately posit that cognitive aberrations in the disorder are due to acute attentional lapses, slowed neural processing, or reduced signal-to-noise ratios. However, they make similar predictions about behavioral summary statistics (response times [RTs] and accuracy), hindering the field's ability to produce strong and specific tests of these theories. The current study uses the linear ballistic accumulator (LBA; Brown & Heathcote, 2008), a mathematical model of choice RT tasks, to distinguish between competing theory predictions. Children with ADHD (n = 80) and age-matched controls (n = 32) completed a numerosity discrimination paradigm at 2 levels of difficulty, and RT data were fit to the LBA model to test theoretical predictions. Individuals with ADHD displayed slowed processing of evidence for correct responses (signal) relative to their peers but comparable processing of evidence for error responses (noise) and between-trial variability in processing (performance lapses). The findings are inconsistent with accounts that posit an increased incidence of attentional lapses in the disorder and provide partial support for those that posit slowed neural processing and lower signal-to-noise ratios. Results also highlight the utility of well-developed cognitive models for distinguishing between the predictions of etiological theories of psychopathology. (PsycINFO Database Record

Is Poor Working Memory a Transdiagnostic Risk Factor for Psychopathology?

In contrast to historical conceptualizations that framed psychological disorders as distinct, categorical conditions, it is now widely understood that co- and multi-morbidities between disorders are extensive. As a result, there has been a call to better understand the dimensional liabilities that are common to and influence the development of multiple psychopathologies, as supported and exemplified by the National Institutes of Mental Health (NIMH) Research Domain Criteria (RDoC) framework. We use a latent variable SEM approach to examine the degree to which working memory deficits represent a cognitive liability associated with the development of common and discrete dimensions of psychopathology. In a sample of 415 community recruited children aged 8-12 (n = 170 girls), we fit a bi-factor model to parent reports of behavior from the DISC-4 and BASC-2, and included a latent working memory factor as a predictor of the internalizing, externalizing, and general "p-factor." We found that both the general "p-factor" and externalizing (but not internalizing) latent factor were significantly associated with working memory. When a bi-factor model of externalizing symptomology was fit to further explore this relationship, working memory was only correlated with the general externalizing dimension; correlation with specific inattention, hyperactive/impulsive, and oppositional factors did not survive once the general externalizing dimension was taken into consideration. These findings held regardless of the sex of the child. Our results suggest that working memory deficits represent both a common cognitive liability for mental health disorders, and a specific liability for externalizing disorders.