Mood and Proneness to Boredom Are Associated with Poorer Continuous Performance Test Results,Which May Improve with Methylphenidate Treatment,in Attention-Deficit/Hyperactivity Disorder

Abstract

Objectives:

This study aimed to evaluate the relationship between baseline test of variables of attention (TOVA) performance, attention-deficit/hyperactivity disorder (ADHD) symptom severity, mood symptoms, proneness to boredom in children with ADHD, and to assess the responses of the various scales to methylphenidate treatment.

Methods:

Thirty-three children and adolescents with ADHD, aged 7–18 years, were assessed at baseline with TOVA and treated for 3 months thereafter with methylphenidate. The ADHD Rating Scale (ADHD-RS), Short Boredom Proneness Scale (SBPS), Children's Depression Inventory (CDI) scale, and CDI-academic and social subscale (CDI-AS) were administered to all participants at baseline and after 3 months of methylphenidate (MPH) treatment.

Results:

The baseline TOVA reaction time (RT) and RT variability parameters correlated with baseline SBPS and CDI-AS scores as well as with baseline total CDI scores. Significant improvements were found in ADHD-RS, SBPS, and CDI-AS scores after MPH treatment. The alteration in ADHD-RS correlated with parallel changes in SBPS and CDI-AS scores.

Conclusions:

Mood and proneness to boredom correlate with poor attention-span in children with ADHD. Improvement in ADHD levels after MPH treatment correlates with a parallel decrease in mood symptoms related to academic achievement and social functioning.

Introduction

Attention-deficit/hyperactivity disorder (ADHD) occurs in up to 10% of children and adolescents and is a major clinical and public health problem due to its associated morbidities and disabilities (Milberger et al. 1995; Spencer et al. 1999). Youths with ADHD are at risk to develop depressive disorder as well as depression or dysthymia symptoms related to chronic social, familial, and academic difficulties (Waxmonsky 2003).

The phenomenon of boredom is linked to ADHD, and shares overlapping mechanisms with depression. Increased boredom was reported among children and adolescents with ADHD, and was found to be associated with clinically significant cognitive impairment (Hunter and Eastwood 2018). ADHD-related cognitive deficits were also reported to be significant predictors of proneness to boredom (Watt and Vodanovich 1992; Maggini 2000; Kass et al. 2003; Gerritsen et al. 2014). Malkovsky et al. (2012), evaluated the relationship between proneness to boredom and sustained attention in adults with ADHD and found that patients with higher levels of proneness to boredom performed poorer on task of sustained attention and demonstrated more symptoms of both ADHD and depression. In a survey of 1928 undergraduate students Isacescu et al. (2017) found a strong relationship between proneness to boredom and cognitive and affective dysregulation. They proposed that proneness to boredom is linked to various forms of cognitive and affective dysregulation, including poor self-control and depression. Boredom and depression have been shown to overlap significantly (Farmer and Sundberg 1986).

In an attempt to determine the effectiveness of psychostimulants in the treatment of depression and to assess related adverse events, Candy et al. (2008) performed a meta-analysis of 24 randomized clinical trials (RCTs) in adults with depression. Three of the RCTs demonstrated that oral psychostimulants, used short term as a monotherapy, reduced the depressive symptoms significantly as compared with placebo and were well tolerated. Hechtman et al. (2004) demonstrated the beneficial effects of methylphenidate (MPH) treatment on functional outcomes, including social skills, classroom behavior, emotional status, and academic achievement in children with ADHD.

Golubchik et al. (2013) found that MPH treatment is effective for both ADHD and subsyndromal depression symptoms. It seems that ADHD symptoms are less responsive to MPH in patients with relatively high Child Depression Rating Scale scores (subthreshold depression) and that those patients may be candidates for selective serotonin reuptake inhibitors to supplement their MPH treatment.

Golubchik et al. (2017) assessed the response to MPH treatment for depression symptoms in patients with Asperger syndrome combined with ADHD. They found a positive correlation between the reductions in ADHD Rating Scale (ADHD-RS) and Children's Depression Inventory (CDI) scores (r = 0.59, p = 0.039). MPH was especially effective in alleviating depression and school-related anxiety symptoms in patients with Asperger's syndrome (AS) and comorbid ADHD. Kutlu et al. (2017) reported that symptoms of ADHD and emotional dysregulation (ED) improved significantly after 1-year of MPH treatment (p < 0.05). The improvement in ED was independent of improvement in ADHD symptoms or of Parent Training (p < 0.05). ED is highly prevalent in disruptive behavioral disorders, expressed as oppositional defiant disorder and in conduct disorder, which are common comorbidities in ADHD. MPH treatment was effective in alleviating ED symptoms, independently of other clinical parameters. Cubero-Millan et al. (2014) concluded that MPH ameliorates depressive symptoms in children with ADHD.

Recently, Golubchik et al. (2020) assessed the relationship between ADHD severity and proneness to boredom in children with ADHD, both on and off MPH. Significant correlation was found at baseline between the Parent Rated-ADHD Rating Scale (PR-ADHD-RS) scores and the Short Boredom Proneness Scale (SBPS) scores (p = 0.027). Both ADHD and boredom levels decreased significantly after 3 months of MPH treatment and the correlation between the reductions in the two scores was found to be significant (p = 0.045). MPH discontinuation for 3 weeks resulted in mild but statistically significant increases in ADHD and SBPS levels, whereas readministration of MPH treatment for another 3 months resulted in parallel improvement in ADHD severity and in the level of proneness to boredom.

The aim of this study was to evaluate the relationship between baseline test of variables of attention (TOVA) performance, ADHD severity, proneness to boredom, and level of depression symptoms (especially those related to academic and social functioning), in children with ADHD, as well as evaluating the impact of 12 weeks of MPH treatment.

The authors hypothesized that at baseline, cognitive deficits, as measured by the TOVA, correlate with ADHD severity, proneness to boredom and level of depression symptoms and that MPH treatment is associated with improvements in all these clinical parameters.

Methods

Participants

The study included 30 children and adolescents aged 7–18 years, from an ambulatory clinical setting. Diagnoses of ADHD were established in interviews conducted by a senior child and adolescent psychiatrist according to the guidelines of Kiddie-Schedule for Affective Disorders and Schizophrenia—Present and Lifetime Version (Kaufman et al. 2000). All participants met the criteria for ADHD according to the Diagnostic and Statistical Manual of Mental Disorders, Fourth Text Revision Edition (DSM-IV-TR) (American Psychiatric Association [APA] 2000). Severity of ADHD was assessed using the PR-ADHD-RS (DuPaul et al. 2016).

Subjects with diagnosis of intellectual disability, organic brain syndromes, psychosis, bipolar disorder, or autism spectrum disorder were not included in the study.

Measures

The TOVA is among the most commonly used continuous performance tests (CPTs) and has been studied and validated in both children and adults (Greenberg and Waldman 1993). The TOVA is used as an aid for diagnosis as well as for the assessment of response to treatment. The main indices of the TOVA include omission errors (O)—a measure of inattention, commission errors (C)—a measure of response inhibition or impulsivity, reaction time (RT)—measures speed of information processing and motor response, RT variability (RTV)—calculated as the standard deviation of RT and believed to reflect consistency or variability of attention and finally, the Attention Comparison Score—a measure of a person's overall performance on the TOVA compared with the TOVA performance of other individuals diagnosed with ADHD (Greenberg and Waldman 1993).

Patient assessment with TOVA was done only at baseline (time 0).

ADHD symptom severity was assessed using the PR-ADHD-RS (DuPaul et al. 2016). It includes 9 items measuring symptoms of inattention and 9 items measuring symptoms of hyperactivity and impulsivity, all based on the ADHD diagnostic criteria in the DSM-IV-TR. ADHD-RS is widely used as a measure of ADHD severity in clinical trials of children and adolescents.

Affective, cognitive, and behavioral symptoms of depression were assessed using CDI, a 27-item self-rated questionnaire (Kovacs 1985; Zalsman et al. 2005). In addition to using the total CDI scale, a subscale consisting only of the academics-related and social functioning-related items of CDI, defined as CDI-academic and social subscale (CDI-AS), was used as well. The latter scale included a sum of the items related to social functioning (items 4, 12, 20, and 21) in addition to those related to school problems (items 15 and 23) and to externalizing behavior (items 5, 26, and 27) (Gomez et al. 2012).

Proneness to boredom was measured with SBPS, which is a self-report questionnaire consisting of 8 items with good internal consistency and construct validity comparable with the original Boredome Proneness Scale (Struk et al. 2017). It includes the following items: (1) I often find myself at “loose ends,” not knowing what to do; (2) I find it hard to entertain myself; (3) many things I have to do are repetitive and monotonous; (4) it takes more stimulation to get me going than for most people; (5) I don't feel motivated by most things that I do; (6) in most situations, it is hard for me to find something to do or watch to keep me interested; (7) much of the time, I just sit around doing nothing; and (8) unless I am doing something exciting, even dangerous, I feel half-dead and dull (Struk et al. 2017).

Procedures

Patients were administered the rating scales at baseline (time 0) and at endpoint (time 12 weeks), with the exception of TOVA, which was administered only at baseline. All received MPH (1 mg/kg) during the trial, with the dose adjusted for each individual according to his or her tolerability and the medication's personal efficacy. Final dosages ranged from 10 to 54 mg/day. All patients were instructed to report any occurring side effect.

All psychometric measures were completed during the first visit, before initiating MPH treatment and again, after 12 weeks of treatment (i.e., at endpoint).

Informed consent was obtained from all the children and their parents. The study was approved by the Geha institutional review board.

Data analysis was performed using two-tailed paired Student's t-tests and Spearman's correlation test, as appropriate. All results are expressed as mean ± SD.

Results

Thirty-three children and adolescents (24 boys and 9 girls, aged 12.2 ± 1.9 years) were included in the study.

Table 1 shows the TOVA baseline scores for main indices as well as the psychometric scale scores before and after MPH treatment. It should be noted that TOVA was performed only at baseline.

Table 1.

Psychometric Rating Scales Before and After MPH Treatment

Scale	Mean ± SD		Paired t-test	p
Scale	Before MPH	After MPH	Paired t-test	p
TOVA-ACS	−1.9 ± 3.3
TOVA-RTV	84.4 ± 23.3
TOVA-RT	85.9 ± 27.3
TOVA-O	70.5 ± 32.0
TOVA-C	84.7 ± 24.3
ADHD-RS	33.9 ± 9.6	24.5 ± 5.9	7.5	0.0001
CDI-AS	4.8 ± 1.7	4.2 ± 1.8	3.5	0.0120
SBPS	19.7 ± 6.5	17.6 ± 5.2	3.3	0.0023
CDI	13.2 ± 3.9	12.6 ± 4.2	1.9	0.0653

ACS, attention comparison score; ADHD, attention-deficit/hyperactivity disorder; ADHD-RS, ADHD rating scale; C, commission errors; CDI, children's depression inventory; CDI-AS, CDI-academic/social-subscale sum of items; MPH, methylphenidate; O, omission errors; RT, reaction time; RTV, RT variability; SBPS, short boredom proneness scale; TOVA, test of variables of attention.

As can be seen, significant decreases were found in the scores of ADHD-RS, SBPS and CDI-AS, after MPH treatment. CDI total scores, however, were not affected by MPH treatment.

Table 2 shows the correlations at baseline between TOVA variables and ADHD-RS, SBPS, CDI, and CDI-AS variables. Several of the correlations were found positive, as can be seen in the table.

Table 2.

The Correlations Between TOVA Variables and Corresponding ADHD-RS, SBPS, CDI, and CDI-AS Variables, at Baseline

	r	95% CI	p
TOVA-RTV vs. ADHD-RS	−0.37	−0.630 to −0.0250	0.037
TOVA-RT vs. ADHD-RS	−0.40	−0.655 to −0.068	0.020
TOVA-C vs. ADHD-RS	−0.04	0.377 to 0.309	0.830
TOVA-O vs. ADHD-RS	−0.35	−0.621 to −0.011	0.044
TOVA-RTV vs. SBPS	0.39	0.048 to 0.643	0.027
TOVA-RT vs. SBPS	−0.38	−0.640 to −0.042	0.029
TOVA-C vs. SBPS	0.15	−0.201 to 0.471	0.397
TOVA-O vs. SBPS	0.10	−0.249 to 0.431	0.569
TOVA-RTV vs. CDI	−0.04	−0.380 to 0.306	0.816
TOVA-RT vs. CDI	0.40	0.066 to 0.65	0.021
TOVA-C vs. CDI	0.05	−0.296 to 0.389	0.769
TOVA-O vs. CDI	−0.10	−0.429 to 0.251	0.577
TOVA-RTV vs. CDI-AS	−0.35	−0.620 to −0.009	0.045
TOVA-RT vs. CDI-AS	0.42	0.095 to 0.670	0.014
TOVA-C vs. CDI-AS	−0.01	−0.349 to 0.338	0.973
TOVA-O vs. CDI-AS	0.02	−0.330 to 0.356	0.935

Table 3 shows the correlations between the changes achieved after MPH treatment. Significant correlations were found between changes in ADHD-RS and in CDI-AS subscores, between changes in SBPS and CDI-AS subscores and between changes in ADHD-RS and changes in SBPS. No significant correlation was found between changes in SBPS and in CDI.

Table 3.

Correlations Between the Changes in the Psychometric Scales After MPH Treatment of ADHD-RS, SBPS, CDI, and CDI-AS

Scales	r	95% CI	p
ΔADHD-RS vs. ΔCDI	0.32	−0.025 to 0.599	0.068
ΔADHD-RS vs. ΔCDI-AS	0.39	0.035 to −0.660	0.045
ΔSBPS vs. ΔCDI	−0.06	−0.175 to −0.490	0.720
ΔSBPS vs. ΔCDI-AS	0.42	0.088 to 0.660	0.015
ΔADHD-RS vs. ΔSPBS	0.40	0.048 to 0. 670	0.027

Discussion

This study evaluated the associations between pretreatment TOVA performance and between pretreatment levels of proneness to boredom and mood. In the mood assessment, the focus was on CDI items relevant to the social and academic domain (CDI-AS). However, although in the case of ADHD proneness to boredom is likely to be a mood measure, it may also be a measure of salience to environmental stimuli, a concept long studied in ADHD (Tegelbeckers et al. 2015).

As expected, with the exception of the TOVA-C (commission errors) score, TOVA baseline parameters correlated inversely with baseline ADHD-RS scores, indicating that severe ADHD is associated with poorer capacity to maintain attention.

Similarly, negative correlation was found between baseline proneness to boredom and TOVA-RT scores. This study also found positive correlations between TOVA-RT and CDI and between TOVA-RT and the CDI-AS subscale. Thus, it seems that a stronger tendency to depression impacts TOVA performance negatively.

The association among lower RTV and RT in TOVA, high levels of proneness to boredom and mood symptoms in children and adolescents with ADHD, may point to an overlap between ADHD severity, proneness to boredom, and low mood. Such overlap has been previously suggested by Farmer and Sundberg (1986).

Boredom is generally defined as a period when information processing loads are low or suboptimal (Zakay 2014). Kent et al. (2019) suggested that boredom is associated with slow passage of time and experiences of varying degrees of depression, hopelessness, loneliness, and distractibility. It is likely that the perception of the slow passing of time experienced by boredom-prone individuals is associated with negative effects.

This study's findings are similar to the findings of Roy et al. (2017) who demonstrated that adolescents with ADHD have lower RTV in CPT, whereas those with comorbid depression have poorer working memory maintenance. Thus, one may conclude that adolescents with ADHD and comorbid depression symptoms have poorer attention span than adolescents with ADHD only. It can be speculated that the development of low mood may increase the cognitive burden associated with ADHD, leading to difficulties in working memory maintenance and thus in attention span. Alternatively, poor cognitive functioning may result in development of low mood in adolescents with ADHD.

Significant reductions in ADHD-RS, SBPS, and CDI-AS subscales were detected after MPH treatment. The significant improvement in SBPS is consistent with our previous study demonstrating less proneness to boredom in children maintained on MPH treatment compared with their scores when MPH treatment is discontinued (Golubchik et al. 2020).

In this study, the magnitude of the improvement in ADHD symptoms was correlated with the extent of reduction in symptoms associated with academic and social difficulties, as assessed by the CDI-AS subscale (r = 0.39; p = 0.045). A possible explanation for this parallel reduction may be related to improvement in general functioning, including in the attentive-behavioral and academic-social domains. In contrast, no significant positive correlation was found between the reductions in ADHD-RS and total CDI scores, indicating no association with low mood. It should be noted, however, that since the participants did not meet DSM-5 criteria for major depressive disorder, further improvement in mood was not possible.

It is suggested that in cases similar to those in this study, where there is presence of ADHD with mild levels of depression or low mood (as measured by total CDI score at baseline), the improvement in ADHD symptoms after MPH treatment does not affect the global mood score, but does affect selectively, the school-related symptomatology (CDI-AS subscales). This was shown in previous studies by Golubchik et al. (2013, 2017). In addition, significant positive correlation was found between changes in ADHD-RS and CDI-AS subscale scores after MPH treatment.

Previous studies demonstrated beneficial effects of MPH treatment on social communication, self-regulation, affect-regulation, and depression symptoms in children with ADHD, with or without comorbid autism spectrum disorder (Jahromi et al. 2009; Golubchik et al. 2017). ADHD is often associated with feelings of distress and incompetence and feeling a failure at school. It is thus likely that the improvement in attention is associated with successful MPH treatment that is reflected in better performance at school, self-confidence, and self-control leading to attenuation of the distress presented by school demands.

In a previous study (Golubchik et al. 2020), the authors also observed a decrease in levels of proneness to boredom, after MPH treatment. Malkovsky et al. (2012) evaluated the relationship between proneness to boredom and sustained attention, in patients with ADHD. He found that patients with higher levels of proneness to boredom performed poorer on tasks that require sustained attention and demonstrated more symptoms of both, ADHD and low mood. Watt and Vodanovich (1999) reported that higher boredom proneness scores are significantly related to poor academic satisfaction. MPH-related improvement in ADHD symptomatology and academic achievements at school are associated with better general functioning and well-being (Golubchik et al. 2018).

It seems that the MPH-related improvement in attention, impulsiveness, and hyperactivity, and possibly also in corresponding neurocognitive performance, may also be beneficial for proneness to boredom and academic functioning related to low mood (CDI-AS; rather than to ADHD per se). Such positive correlations were found in the aforementioned study between improvement in proneness to boredom and reduction in symptoms associated with academic and social difficulties, as assessed by the CDI-AS subscale (r = 0.42; p = 0.015). That study, however, did not include assessment of mood. Moreover, the CDI-AS subscale that includes CDI items on openness, sociability, and school performance may tap into general impairment that is related to ADHD, rather than being necessarily mood related.

Limitations

The major limitations of this study are the open-label design, the relatively small sample size (N = 33), the lack of neurocognitive assessment after MPH treatment, the relatively short MPH treatment duration (12 weeks) and the lack of long-term follow-up of patients who continued the MPH treatment or stopped it. Furthermore, the participants in the study had subthreshold CDI levels, which were not quite in the range of depression. Thus, the generalizability of the impact of MPH treatment on depression symptoms or even low mood is limited. Moreover, no data were collected on psychosocial functioning and other comorbidities or on subclinical anxiety levels.

Conclusions

Baseline TOVA performance parameters, especially RT and RTV, correlate positively with the levels of proneness to boredom and low mood (CDI) in children with ADHD. Improvement in ADHD levels after MPH treatment correlate with parallel decreases in the levels of boredom and low mood, which are relevant to academic and social functioning (CDI-AS). These findings indicate significant interactions between parameters of sustained attention (RT and RTV) that are impaired in ADHD, proneness to boredom, and low mood, a clinical complexity that responds favorably to MPH treatment.

Clinical Significance

Mood and proneness to boredom correlate with poor attention-span in children with ADHD. This study demonstrated significant interactions between capacity to maintain sustained attention, proneness to boredom, and low mood in a pediatric population with ADHD and the beneficial effect of methylphenidate treatment in this complex condition. The study confirmed proneness to boredom to be an important dimension of the descriptive phenomenology of ADHD, in children whose boredom-severity correlates with objective measures of impaired attention, academic performance, and mood. Our data, moreover, support clinical intervention with methylphenidate for the correlated domains of proneness to boredom, attention, academic performance, and mood, in appropriately selected children and adolescents. Clinicians should be aware of the impact of proneness to boredom and low mood when considering pharmacotherapy in ADHD.

Footnotes

Acknowledgment

The authors thank Ms. Michaella Gerchak for editorial services.

Disclosures

Dr. Pavel Golubchik and Dr. Gila Schoen report no conflict of interest with regard to this study and no financial relationships whatsoever with any pharmaceutical company. Prof. Abraham Weizman reports no conflict of interest with regard to this study. He received honoraria from pharmaceutical companies (Novartis, Janssen, Pfizer, Lundbeck, Teva, and Medison Pharma) for educational lectures unrelated to this study.

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