Differences in Perceived Mental Effort Required and Discomfort during a Working Memory Task between Individuals At-risk And Not At-risk for ADHD

Self-Stigma of Canadian Youth With ADHD and Their Parents

OBJECTIVE

ADHD is subject to stigma from the general population. Exposure to stigma poses the risk of developing self-stigma of youth and parents, but few studies have focused on self-stigma of ADHD. Furthermore, parental factors have been implicated in self-stigma of youth, but no previous research has assessed the association between self-stigma of parents and youth. Therefore, the objective of this study was to better understand the experience of self-stigma of youth and their parents in the context of ADHD.

METHOD

Fifty-five youth with ADHD (aged 8-17) and one parent reporter per youth completed surveys to report their experiences.

RESULTS

The results of this study found that both youth and parents reported significantly lower self-stigma scores compared to most previously published research. Parents of boys reported higher self-stigma scores compared to parents of girls. Youth who reported higher self-stigma also reported lower self-esteem. Self-stigma scores in youth were predicted by inattentive symptoms but not hyperactive/impulsive symptoms or parental self-stigma.

CONCLUSION

Results emphasize the importance of understanding self-stigma of ADHD, symptom severity, and the need for interventions for families with ADHD.

Engagement of mental effort in response to mental fatigue: A psychophysiological analysis

Acute mental fatigue, characterized by a transient decline in cognitive efficiency during or following prolonged cognitive tasks, can be managed through adaptive effort deployment. In response to mental fatigue, individuals can employ two main behavioral patterns: engaging a compensatory effort to limit performance decrements, or disengaging effort, leading to performance deterioration. This study investigated the behavioral pattern used by participants in mental fatigue conditions. Fifty participants underwent a sequential-task protocol with counterbalanced sessions who took place in two separate sessions: a 30-min incongruent Stroop task (fatiguing session) or a 30-min documentary viewing task (control session), followed by a time-to-exhaustion (TTE) handgrip task at 13 % of maximal voluntary contraction. Psychophysiological measures included the preejection period, heart rate variability, blood pressure, and respiration. Behavioral results showed deteriorated TTE handgrip performance after the Stroop task compared to after the documentary viewing task. During the Stroop task participants were more conservative and prioritized accuracy over speed. Self-reported fatigue was greater after the Stroop task. Psychophysiological data revealed a gradual decrease in sympathetic activity over time in both tasks, with the Stroop task showing a more pronounced decrease. Taken together, these findings suggest a disengagement of effort for a large proportion of participants (49 %) that could be partly attributed to a habituation to the demands of the Stroop task. This study illustrates the interplay of behavioral patterns of effort investment in the context of mental fatigue and underscores the role of disengagement as a dominant response to this phenomenon among healthy participants.

Coping with emotional dysregulation among young adults with ADHD: A mixed-method study of self-awareness and strategies in daily life

BACKGROUND

Emotional dysregulation (ED) impacts functional outcomes among individuals with attention-deficit hyperactivity disorder (ADHD). Self-awareness and strategies may enhance coping with ED yet are rarely studied in ADHD.

OBJECTIVES

To explore ED-related self-awareness and strategies in daily life of adults with ADHD, and to examine the interrelations between them and their association with symptoms.

METHODS

Sixty young adults with ADHD participated in a mixed-method study. At baseline, self-awareness and strategies were assessed using the Self-Regulation Skills Interview (SRSI); ADHD symptoms were self-rated using the ASRS symptom checklist. Then, symptoms were rated over 5-days using ecological momentary assessment (EMA).

RESULTS

Significant challenges in self-awareness and strategies were demonstrated quantitatively and qualitatively. Awareness of ED was associated with variability of ADHD symptoms on EMA yet not with symptom severity. Qualitative content analysis revealed a range of self-awareness levels, which were related to noticing ED-related cues and understanding contextual factors predictive of ED. Self-awareness and strategies were significantly associated. Strategies varied regarding effort, individual preference and temporality.

CONCLUSIONS

Variability of ADHD symptoms was negatively associated with self-awareness of ED. Strategy selection in daily-life among adults with ADHD may be affected by self-awareness and by a possible trade-off between short-term effort and long-term effectiveness.

The experience of effort in ADHD: a scoping review

Background

Mental effort plays a critical role in regulating cognition. However, the experience of mental effort may differ for individuals with Attention-Deficit/Hyperactivity Disorder (ADHD), a disorder for which sustained mental effort 'avoidance' or 'dislike' is a criterion in the DSM. We conducted a scoping review to characterize the literature on the experiences of effort in ADHD.

Methods

This systematic scoping review adhered to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) Extension for Scoping Reviews and Joanna Briggs Methodology. PsycINFO (OVID), PsycINFO (ProQuest) and PubMed were searched for studies published in English before February 14, 2023. Studies must have included an ADHD population or a measure of ADHD symptomatology, in addition to a self-report measure of the experience of effort or the use of an effort preference paradigm. Two researchers reviewed all abstracts, and one researcher reviewed full-text articles.

Results

Only 12 studies met the inclusion criteria. Several gaps and inconsistencies in the research were identified in terms of method, definitions of effort, measurements of ADHD, and sample characteristics. Moreover, the pattern of results on the experience of effort was mixed.

Conclusion

Despite its diagnostic and conceptual significance, the experience of mental effort in ADHD is not well studied. Critical gaps were identified in the existing literature. A three-facet conceptualization of effort is proposed-specifically, task-elicited effort, volitionally exerted effort, and the affect associated with engaging in effort - to guide future explorations of the experience of effort in ADHD.

What Is Mental Effort: A Clinical Perspective

Although mental effort is a frequently used term, it is poorly defined and understood. Consequently, its usage is frequently loose and potentially misleading. In neuroscience research, the term is used to mean both the cognitive work that is done to meet task demands and the subjective experience of performing that work. We argue that conflating these two meanings hampers progress in understanding cognitive impairments in neuropsychiatric conditions because cognitive work and the subjective experience of it have distinct underlying mechanisms. We suggest that the most coherent and clinically useful perspective on mental effort is that it is a subjective experience. This makes a clear distinction between cognitive impairments that arise from changes in the cognitive apparatus, as in dementia and brain injury, and those that arise from subjective difficulties in carrying out the cognitive work, as in attention-deficit/hyperactivity disorder, depression, and other motivational disorders. We review recent advances in neuroscience research that suggests that the experience of effort has emerged to control task switches so as to minimize costs relative to benefits. We consider how these advances can contribute to our understanding of the experience of increased effort perception in clinical populations. This more specific framing of mental effort will offer a deeper understanding of the mechanisms of cognitive impairments in differing clinical groups and will ultimately facilitate better therapeutic interventions.

Amphetamines Improve the Motivation to Invest Effort in Attention-Deficit/Hyperactivity Disorder

Prevailing frameworks propose that a key feature of attention-deficit/hyperactivity disorder (ADHD) is lower motivation. An important component of motivation is the willingness to engage in cognitively or physically effortful behavior. However, the degree to which effort sensitivity is impaired in ADHD has rarely been tested, and the efficacy of stimulant medication in ameliorating any such impairments is unclear. Here, we tested 20 individuals with ADHD (11 males, 9 females) who were managed with amphetamine-based medication (dexamfetamine, lisdexamfetamine), and 24 controls (8 males, 16 females). Individuals with ADHD were tested over two counterbalanced sessions, ON and OFF their usual amphetamine-based medication. In each session, participants performed an effort-based decision-making task, in which they were required to choose how much cognitive or physical effort they were willing to engage in return for reward. Our results revealed three main findings. First, individuals with ADHD had lower motivation relative to controls to invest effort in both the cognitive and physical domains. Second, amphetamine increased motivation uniformly across both domains. Finally, the net effect of amphetamine treatment was to mostly restore motivation across both domains of effort relative to healthy controls. These data provide clear evidence for a heightened sensitivity to both cognitive and physical effort in ADHD, and reveal the efficacy of amphetamine-based drugs in restoring effort sensitivity to levels similar to controls. These findings confirm the existence of reduced motivational drive in ADHD, and more broadly provide direct causal evidence for a domain-general role of catecholamines in motivating effortful behavior.SIGNIFICANCE STATEMENT A core feature of attention-deficit/hyperactivity disorder (ADHD) is thought to be a heightened aversion to effort. Surprisingly, however, the degree to which effort sensitivity is impaired in ADHD has rarely been tested. More broadly, the relative efficacy of catecholamines in motivating the investment of cognitive and physical effort is unclear. We tested 20 individuals with ADHD ON and OFF amphetamines, and compared their behavior on an effort-based decision-making task to 24 controls. When tested OFF medication, the ADHD group was less cognitively and physically motivated than controls. However, amphetamines led to a comparable increase in motivation across both domains. This demonstrates the efficacy of catecholamines in facilitating domain-general effort, and highlights the broader potential of such drugs to treat disorders of motivation.

ADHD and the avoidance of mental effort: the role of response inhibition and avoidance motivation

OBJECTIVE

The tendency of people with ADHD to avoid tasks that require mental effort impacts their academic achievement. Findings in the literature suggest that children with ADHD find cognitive tasks more effortful and uncomfortable than their typically developing peers. However, neuropsychological processes contributing to this remain unclear. The present study investigated whether the relationship between prepotent motor response inhibition and avoiding mental effort is mediated by the ability to resist avoidance motivation and whether this proposed mediation mechanism is contingent on ADHD diagnosis.

METHOD

40 children with ADHD and 40 gender and age-matched typically developing peers participated in the study. They completed the Cognitive Effort Avoidance Measure, the Go/No-go Task, and the Reinforcement Sensitivity Theory-Personality Questionnaire-Children. Mediation and moderated mediation analyses were employed to test the hypotheses.

RESULTS

Children with ADHD scored lower in response inhibition and resisting avoidance motivation. Poorer scores in these variables were associated with a higher avoidance rate. Moreover, the ability to resist avoidance motivation completely mediated the relationship between response inhibition and avoidance rate only among children with ADHD.

CONCLUSION

Findings imply that poorer response inhibition led to an increase in avoidance motivation among children with ADHD, which becomes challenging to regulate effectively due to an impairment in the ability to resist avoidance motivation. Theoretical and clinical implications are discussed.

Factors Predicting Mental Effort Associated With Verbal Fluency: Cue Types, Switching, and Fear of Negative Evaluation

PURPOSE

Verbal fluency, a task frequently employed in neuropsychological assessment, provides important word productivity data but little information about subjective effort associated with demand monitoring and resource allocation. In two experiments, this study investigated the effects of task variables (semantic vs. phonemic cues; alternating vs. nonalternating conditions) and personal factors (fear of negative evaluation and trait anxiety) on subjective effort for a wide variety of verbal fluency tasks in neurotypical individuals.

METHOD

Twenty-one adults completed eight verbal fluency tasks in Experiment 1. The tasks were selected to examine effort reported for verbal fluency that differed in (a) cue types and (b) the disruptions of clustering strategies. In Experiment 2, a separate group of 50 adults completed two verbal fluency tasks twice in separate sessions. Participants also completed social-emotional measures including fear of negative evaluation and trait anxiety. Working memory was assessed as a control variable.

RESULTS

Experiment 1 showed greater effort for completing semantic than phonemic cue tasks and greater effort for alternating than nonalternating conditions. Alternating semantic verbal fluency yielded the greatest effort among all tasks. Differences in effort could not be accounted for by performance alone. Experiment 2 showed that greater fear toward negative evaluation was associated with greater effort. The relationship between fear and effort was not related to trait anxiety or moderated by performance levels or repeated testing.

CONCLUSIONS

Knowledge about factors that impact subjective effort in neurotypical individuals is fundamental to accurate interpretation of effort reported by clinical populations. This study demonstrated the multifaceted nature of subjective effort that could not be accounted for by performance alone. In addition to task variables, effort assessment needs to consider the impact of social-emotional factors such as fear toward negative evaluation.

Effort-Related Decision-Making in ADHD

ADHD is defined by behavioral symptoms that are not well characterized in relation to ADHD’s neurobiological mechanisms. This approach has limited our ability to define ADHD nosology and predict outcomes because it does not systematically examine facets of the disorder such as the inability to maintain cognitively effortful activities, as promoted in the NIMH RDoC approach. Existing data indicate ADHD is associated with differences in reward valuation and processing, but we do not know whether ADHD is also associated with higher levels of aversion to exerting cognitive effort and/or altered reward x effort interactions. Our ongoing study addresses this knowledge gap by examining individuals’ preferences between rewards associated with minimal effort and reward alternatives with a higher payoff but higher effort costs (“effort discounting”); thereby permitting us to characterize differences in biases and tradeoffs during effort-related decision-making in ADHD. The study takes advantage of a well-defined sample of ADHD-diagnosed and healthy control individuals to address three aims. First, we determine whether ADHD is associated with steeper discounting of larger, more effortful rewards. Second, we examine the subjective perception of effort in youth diagnosed with ADHD and healthy controls using tasks requiring varying levels of cognitive effort. Third, we explore relationships amongst indices of effort discounting, theoretically-related traits (e.g., grit, distress tolerance), biomarkers of effort-related decision-making (eye movements and pupil size), and various cognitive measures. Successful completion of the aims will permit us to better characterize ADHD-healthy control differences and lay a foundation for more computational approaches to ADHD diagnostic criteria.

Anticipated, experienced, and remembered subjective effort and discomfort on sustained attention versus working memory tasks

This study examined individuals' ability to accurately anticipate how cognitively effortful and uncomfortable a task will feel based on a short sample of the task. Participants completed a sustained attention or working memory task. Post-practice, participants rated the effort and discomfort that they anticipated their task would require and engender, respectively. Participants also rated their effort and discomfort during task-administration and the effort and discomfort they recalled feeling after task-administration. Sustained attention task participants anticipated significantly less effort than working memory task participants. Sustained attention task participants felt significantly more effort during the task and remembered feeling more effort than they had anticipated. Working memory task participants felt significantly less effort during the task than they had anticipated. Sustained attention task participants anticipated, experienced, and recalled feeling more discomfort than working memory task participants. Individuals' anticipation of effort required depends on the task and is different from the effort they actually feel during the task and later recall feeling.

Methylphenidate increases willingness to perform effort in adults with ADHD

BACKGROUND

A reduced willingness to perform effort based on the magnitude and probability of potential rewards has been associated with diminished dopamine function and may be relevant to attention-deficit/hyperactivity disorder (ADHD). Here, we investigated the influence of ADHD status and methylphenidate on effort-based decisions. We hypothesized that ADHD participants would make fewer high-effort selections than non-ADHD subjects, and that methylphenidate would increase the number of high-effort selections. Furthermore, we hypothesized there would be associations among ADHD severity and methylphenidate-related changes in effort-based and attentional performance across all participants.

METHODS AND PARTICIPANTS

ADHD (n = 23) and non-ADHD (n = 23) adults completed the Effort Expenditure for Rewards Task in which participants select between low-effort and high-effort options to receive monetary rewards at varying levels of reward magnitude and probability. A test of attentional performance was also completed.

RESULTS

Overall, participants made more high-effort selections as potential reward magnitude and probability increased. ADHD participants did not make fewer high-effort selections than non-ADHD participants, but ADHD participants showed greater methylphenidate-related increases in high-effort selections. ADHD participants had worse attentional performance than non-ADHD participants. ADHD severity was associated with methylphenidate-related changes in high-effort selections, but not changes in attentional performance.

CONCLUSIONS

These results indicate that methylphenidate increases the willingness to perform effort in individuals with ADHD, possibly due to disorder-related motivational deficits. This provides support for theories of insufficient effort allocation among individuals with ADHD.

TRIAL REGISTRATION

Clinicaltrials.gov Identifier, NCT02630017.

A novel unstructured performance-based task of executive function in children with attention-deficit/hyperactivity disorder

OBJECTIVE

Executive functions (EFs) have been assessed with performance-based measures and rating scales. Research has shown a lack of association between these two methods. One factor that might contribute to this difference is the structure provided on performance-based measures that is not provided on rating scales. This study examined the role of structure on self-directed task completion, an aspect of EF, using a novel unstructured performance-based task (UPT).

METHOD

Children aged 8-12 years (38 attention-deficit/hyperactivity disorder, ADHD; 42 typically developing) and their caregivers participated. We compared performance on the UPT, performance-based measures of EF (Stroop test and Trail-Making Test), and a rating scale to assess EF (Barkley Deficits in Executive Functioning Scale-Children and Adolescents, BDEFS-CA).

RESULTS

Group differences were found across all measures. Significant associations emerged between the UPT and Stroop test, Trail-Making Test, and BDEFS-CA, but no significant associations were found between the Stroop test or Trail-Making Test and the BDEFS-CA. In regression analyses, performance-based tasks and the rating scale both uniquely predicted UPT performance. The UPT was a significant predictor of group status when entered with performance-based tasks, but the UPT did not enter as a significant predictor when entered with the rating scale.

CONCLUSION

The UPT is a promising measure to assess self-directed task completion in children with ADHD.

A Pilot Study of Behavioral, Physiological, and Subjective Responses to Varying Mental Effort Requirements in Attention-Deficit/Hyperactivity Disorder

Background: Attention-deficit/hyperactivity disorder (ADHD) is presumed to involve mental effort application difficulties. To test this assumption, we manipulated task difficulty and measured behavioral, as well as subjective and psychophysiological indices of effort.

Methods: Fifteen adolescent ADHD boys and 16 controls performed two tasks. First, subjective estimates and behavioral and pupillary measures of effort were recorded across five levels of N-back task difficulties. Second, effort discounting was assessed. In the latter, participants made repeated choices between performing a difficult N-back task for a high reward versus an easier N-back task for a smaller reward.

Results: Increasing task difficulty led to similar deteriorations in performance for both groups – although ADHD participants performed more poorly at all difficulty levels than controls. While ADHD and control participants rated the tasks equally difficult and discounted effort similarly, those with ADHD displayed slightly different pupil dilation patterns with increasing task difficulty.

Conclusion: The behavioral results did not provide evidence for mental effort problems in adolescent boys with ADHD. The subtle physiological effects, however, suggest that adolescents with ADHD may allocate effort in a different way than controls.

Augmented Go/No-Go Task: Mouse Cursor Motion Measures Improve ADHD Symptom Assessment in Healthy College Students

Attention deficit/hyperactivity disorder (ADHD) is frequently characterized as a disorder of executive function (EF). However, behavioral tests of EF, such as go/No-go tasks, often fail to grasp the deficiency in EF revealed by questionnaire-based measures. This inability is usually attributed to questionnaires and behavioral tasks assessing different constructs of EFs. We propose an additional explanation for this discrepancy. We hypothesize that this problem stems from the lack of dynamic assessment of decision-making (e.g., continuous monitoring of motor behavior such as velocity and acceleration in choice reaching) in classical versions of behavioral tasks. We test this hypothesis by introducing dynamic assessment in the form of mouse motion in a go/No-go task. Our results indicate that, among healthy college students, self-report measures of ADHD symptoms become strongly associated with performance in behavioral tasks when continuous assessment (e.g., acceleration in the mouse-cursor motion) is introduced.

Mental effort and discomfort: Testing the peak-end effect during a cognitively demanding task

We applied the peak-end paradigm that was first introduced in the pain literature to examine the experience of effort and discomfort during a cognitively demanding working memory task. A total of 401 participants were asked to rate their effort and discomfort during and after the administration of a working memory task, which systematically varied task difficulty within participants and task duration between participants. Over the course of the task, participants reported a decrease in reported effort and an increase in reported discomfort. Peak and end real-time ratings were significant predictors of retrospective ratings for effort and discomfort; average and initial ratings predicted a small amount of additional variance. The regression analyses with effort and discomfort were largely consistent, with some exceptions. End discomfort significantly predicted willingness to do the task again, but not end effort. These findings highlight the ways in which the experience of effort and discomfort are integrally related, yet importantly separate, during a cognitively demanding task.