Effortful Control – A Transdiagnostic Dimension Underlying Internalizing and Externalizing Psychopathology

The Research Domain Criteria (RDoc) framework [1, 2] grew out of a need to develop new ways of classifying mental disorders for research purposes, based on dimensions of observable behavior and measurable neurobiology. As such, the RDoC framework promotes taking underlying neurobiological factors into account when exploring their role in the pathogenesis of different phenotypical psychopathological presentations. One of the RDoC constructs that has received large attention is that of “control” within the cognitive RDoC domain. Control refers to a system that modulates the operation of other cognitive and emotional systems, in the service of goal-directed behavior, when prepotent modes of responding are not adequate to meet the demands of the current context. This connects closely with the concept of self-regulation (SR) which is considered to have an important role in adaptive and adverse outcomes in children, adolescents, and adults. In temperament research, the construct of “effortful control” is used for studying this SR in children and adolescents whereas in clinical neurocognitive research one uses the construct of “executive functioning” [3, 4].

In the psychobiological model of Rothbart (Fig. 1), temperament is defined as “constitutionally based individual differences in reactivity and SR, influenced over time by heredity, maturation and experience” [5]. Reactivity (e.g., punishment sensitivity related to negative affectivity, reward sensitivity related to positive affectivity, bottom-up regulation) includes responsiveness of emotional, activation, and arousal systems. In Gray’s Reinforcement Sensitivity Theory [6, 7], reactive dimensions of temperament are described in levels of behavioral approach system (BAS) and levels of behavioral inhibition system (BIS), whereby the BAS is sensitive for reward and the BIS is sensitive to punishment [8]. Higher BIS sensitivity is reflected in higher proneness to anxiety and is related to the personality trait of Neuroticism in the Five Factor Model (FFM) [9], elevated BAS sensitivity is reflected in elevated proneness to engage in goal directed efforts and to experience positive feelings and is related to the personality trait of Extraversion in the FFM [8-12]. Reactive temperament can be assessed using the Behavioral Inhibition System/Behavioral Activation System Scales (BIS/BAS) [8].

SR or effortful control (EC) involves the behaviors and processes that one uses to modulate one’s reactivity or reactions to stimuli [13, 14]. Whereas reactivity can be observed early in childhood, SR is developed later in life and progresses from simple reactive control to a more flexible, intentional, and self-directed use of attentional processes often referred to as EC [15]. This process parallels the maturation of the prefrontal cortex and may be conceptualized as top-down regulation of behavior. EC moderates the influence from BIS and BAS. As an aspect of temperament, EC allows flexible regulation of thought, emotion, and is therefore strongly related to executive functioning [16-18].

EC is defined as “the efficiency of executive attention – including the ability to inhibit a dominant response and/or to activate a subdominant response, to plan, and to detect errors” [13 p. 129]. The EC concept consists of 3 components: (1) attentional control which involves the ability to voluntarily focus or shift attention, (2) inhibitory control which is the ability to effortfully inhibit behavior, and (3) activation control which involves the ability to activate behavior even when one is not fully motivated [13, 14, 19]. Regulative temperament can be measured using the Effortful Control Subscale of the Adult Temperament Questionnaire (ATQ-EC) [20]. In sum, it can be stated that EC is the ability to approach a situation which one rather avoids and to inhibit actions which one desires [18] and can be seen as the fundamental basis of SR [15].

EC as a broad concept has been proven to be an important factor with respect to both normal, successful human development and the vulnerability to psychopathology [17] and thus covering a continuum from normality/normal range of personality to psychopathology. With respect to the pathogenesis of mental disorders, poor EC is associated with both internalizing and externalizing psychopathology, i.e. depression, bipolar disorder, eating disorders (ED), personality disorders (PD), ADHD, and addiction [17, 21-26]. Clinically, individuals with low levels of EC are at increased risk for multiple types of psychopathological symptoms across disease categories suggesting, EC can be seen as a transdiagnostic construct.

It is self-evident that impulse control-related diseases (ADHD, substance abuse, ED, behavior addictions) are characterized by disturbances of the inhibitory control component of the EC definition, but the attentional control and activation control components of the EC definition are also relevant aspects of EC in, e.g., the affective disorders.

Although it would be interesting to distinguish between the three components of EC in both internalizing and externalizing disorders, in most studies however the total sum of EC is used since the general concept of EC is of interest [27] and the alpha coefficients of the subscales are often too low, indicating that they are less reliable than the total score [28].

The neurobiological substrate of the EC network has been proposed to constitute of the anterior cingulate cortex (ACC) and the lateral prefrontal cortex [29-31]. This so-called executive attention network functions via top-down processes. The ACC is involved in the detection and monitoring of conflict, whereas lateral prefrontal areas have been shown to be mainly related to conflict resolution [32, 33]. In addition to the role of the ACC in the regulation of cognitive processing, this area appears to be also involved in the regulation of emotions [34] since activation in the dorsal part of the ACC has been seen when participants were performing a Stroop-like task, but in ventral areas when the task involved emotional stimuli [35].

The theoretical link between EC and the executive attention network has resulted in several studies investigating the link between EC self-reports (questionnaires) and performance on executive function tasks [36-38]. Concerning the self-report measures, EC is often measured using temperament questionnaires (self-report questionnaires, e.g. the Early Adolescent Temperament Questionnaire [EATQ] [39], and the Effortful Control Scale [ECS]) [40]. Another measure often used in studies with adults is the conscientiousness scale of the Big Five NEO-FFI [41]. Within the domain of the performance-based tasks, Fan et al.[42] developed the Attention Network Task (ANT) to assess the different attentional networks (and their interrelations) within a single task. More specific, the efficiency of alerting, orienting, and executive attention is measured by evaluating the impact of alerting cues, spatial cues, and flankers on reaction time. Another battery that is used for assessing EC in young children is the Kochanska’s Battery for Assessing Effortful Control (Kochanska’s EC battery). It has tasks that assess abilities for delaying or waiting, slowing down of gross and fine motor activity, suppressing or activating behavior, effortful attention, and lowering of voice or whispering [43]. Inhibitory control is the component of EC that is most studied and which often uses parent or teacher questionnaires for assessing children’s EC or for adults a self-report questionnaire (e.g., ECS) and behavioral tasks for measurement. Behavioral measures/neuropsychological mea-sures often used to tap inhibitory control are the Go/No-Go task (requires responding to one frequent occurring stimulus and inhibiting a response to another less frequently occurring stimulus), the Stroop task (requires ignoring a dominant perceptual feature of a stimulus in favor of a subdominant feature, e.g. naming the color in which a word is printed, instead of reading the word), and the Stop-Go task (requires inhibition of an about-to-be-executed (prepared) motor response [44, 45] besides tasks to tap attentional control (i.e., attention focusing and attention control) [for an overview, see 18]. Another task to study conflict resolution is the flanker task in which a target stimulus is surrounded by irrelevant stimulation that can either match or conflict with the response required by the target [46].

Concerning the questionnaires, we found the Adult Temperament Questionnaire the most reliable and valid as it is known to have a good internal consistency and convergent validity with other measures of temperament and personality. The scale is divided into three subscales: inhibitory control, attentional control, and activation control. Internal consistency for the full scale in the original version was α = 0.78 (inhibitory control α = 0.60, attentional control α = 0.73, and activation control α = 0.69) [28]. Normative data for EC have been reported in a large non-clinical sample (n = 700) [20].

Regarding the performance-based tests, the following measurements have proven the most reliable and valid indicators of EC: Stroop Color and Word test [47], the Go/No-Go Task and the Stop Signal Task [45].

Questionnaires and behavioral measures of inhibition in general show small to moderate correlations, and results seem to depend on the type of neuropsychological measure that is used to tap executive functions. Another explanation of the low correspondence of no correspondence could be that temperament questionnaires measure rather more general identity-related beliefs about experience, whereas neuropsychological tasks assess the momentary situation-related behavioral performance [23, 48, 49]. There is some evidence for a positive relationship between EC and executive attention, but especially when parent reports of the EC of their child are considered. Some research studies therefore question the interchangeability of EC questionnaires and neuropsychological executive functioning tasks when measuring EC [50].

Taken together, EC is considered an important construct within the RDoC cognitive system domain, and cross-sectional studies show its involvement in a broad spectrum of traditional-categorical (DSM-ICD) psychiatric diagnoses. From this perspective, EC might be considered as a prototypical transdiagnostic dimension. However, no recent review has been published exploring the role throughout the adult psychopathological spectrum. Within the current work, we aimed at exploring its role in both internalizing and externalizing psychiatric disorders.

Our narrative review was based upon a literature search in the database PubMed for studies published with search terms EC and adults and clinical disorders (internalizing and externalizing disorders, mood disorders, depressive disorders, anxiety disorders, ED, impulsive disorders, ADHD, substance use disorder (SUD), and behavioral disorders (i.e., gambling, internet gaming, compulsive internet use [CIU], and compulsive buying [CB]). Limits were set in time, between 2008 and 2018, adult age (>18 years) and English. We only included original research papers that reported well-accepted self-report questionnaires or behavioral measures for EC. The combination of the aforementioned search items led to the identification of 29 articles (Fig. 2).

For each study, relevant data, extracted by the first author, addressed the characteristics and findings of the selected studies. Findings are reported for each pathology/psychiatric diagnosis separately, and only significant findings are reported (Table 1).

In total, 29 unique original research articles were included in this review.

Reactive (i.e., punishment sensitivity/negative affectivity, reward sensitivity/positive affectivity) and regulative (EC and attentional mechanisms) temperament factors are increasingly being seen as possible mechanisms underlying increased vulnerability to depression and anxiety [9, 51, 52].

The study of Dinovo and Vasey [53] provides evidence for extending a temperamental model for depression and anxiety to adults. They also stress the importance of taking the regulatory component of temperament, namely EC, into account in understanding the association between temperamental activity and depressive and anxious disorders. They found that persons high in negative reactivity, low in positive reactivity, and low in EC were especially vulnerable for symptoms of depression. Overall, the authors showed an important role of EC in internalizing (depressive, anxious) symptoms, i.e. both as a main effect and as a moderator of the effect of reactive aspects of temperament (BIS/BAS). Of note, this was a (large: n = 477) study in undergraduate students (as part of their academic curriculum), not an identified patient sample, exploring symptoms and not disorders. High levels of negative affect and low levels of EC were also associated with higher levels of anxiety in a study by Tortella-Feliu et al. [54], whereby the prospective association between negative affectivity and avoidance was moderated by EC (high negative affect being related to engaging in avoidance behaviors only for those exhibiting low EC). In a longitudinal study in university students, Nishiguchi et al. [55] explored the temporal relationship between EC, depressive symptoms, and cognitive motivation (need for cognition [NfC]). NfC is a personality trait related to one’s motivation to enjoy effortful cognitive activity. Their findings suggest a temporal relation whereby depressive symptoms caused a decrease in EC both as a main effect and indirectly, mediated by cognitive motivation. This finding could imply that a motivational deficit may partially explain the decreased EC found in depressed patients. Their results moreover showed that the indirect effect of depressive symptoms was significant for all EC subscales. Since inhibition control, activation control and attentional control all require some cognitive effort, the decline of NfC associated with depressive symptoms may predict less efficiency of all aspects of EC.

Clements and Bailey [56] studied the relationship between anxiety and aspects of temperament in their effort to develop a profile that may be used to identify individuals at risk. In their large sample (509 undergraduate students), high positive affect and high EC correlated with low levels of reported anxiety. Another study performed in non-clinical young adults examined the relationship between negative emotionality and depressive symptoms through mediation or moderation of cognitive vulnerability factors (cognitive style, brooding, stress-reactive rumination) and EC but found no moderating role of EC between negative emotionality and cognitive vulnerability factors [57].

A study of Kanske and Kotz [58] showed that EC as a temperamental trait and subclinical depression and anxiety together influence the emotional modulation of executive attention. Participants high in EC and low in depression and anxiety, especially, responded faster to conflict processing (flanker test, Simon task) in emotional stimuli, showed an enhanced ERP conflict negativity, and additional (fMRI) increased activation in the ventral ACC. Of note, this was a study in healthy controls (HC) where subclinical depressive and anxious symptoms were explored, not a clinical population with distinct mood or anxiety disorders. Marchetti et al. [59] compared EC and attentional networks in remitted depressed patients (RMD) and HC as measured with the Adult Temperament Questionnaire-Effortful Control (ATQ-EC) and the ANT. In their sample of 90 RMD and 270 HC, high EC was substantially associated with less depressive and anxiety symptoms regardless of clinical status (i.e., RMD vs. HC) while less efficient executive attention was modestly associated with more depressive complaints in the whole sample. Of interest, no differences were found in EC between HC and RMD. The negative correlation between depressive symptoms and EC could represent an attentional dysfunction, as attentional bias especially for negative information [60] and diminished attentional control are associated with depression.

Burdick et al. [61] performed a study on 24 patients with bipolar I or bipolar II disorder (both in the depressive phase), and an HC group with performance-based tasks in order to measure attention and psychomotor functioning. Relative to the HC, the bipolar sample demonstrated evidence of psychomotor slowing and revealed deficits on measures of effortful attention, yet demonstrated comparable performance on measures of automatic attention. These results suggest an attentional impairment during the depressed phase of bipolar disorder that may be specific to effortful processing, while automatic processes remain relatively intact. Murphy et al. [64] found manic patients were impaired in their ability to inhibit behavioral responses (low levels of inhibitory control, subcomponent of EC) and focus attention, but depressed patients were impaired in their ability to shift the focus of attention and exhibited an affective bias for negative stimuli (low levels of attentional control, subcomponent of EC).

Aspects of reactive and regulative temperament also play an important role in the etiology of ED. EC is one of the constructs most often named in research investigating the development and maintenance of ED. Several studies found individuals with high NA and low EC are more at risk for developing ED symptomatology [63-65]. Low EC was also found to be associated with impulsiveness in binging/purging ED [63, 66].

As mentioned above, several studies showed that high NA and low EC place individuals at risk for developing ED symptomatology.

Zwaan et al. [67] investigated the association between reactive and regulative aspects of temperament and severe weight cycling in overweight and obese individuals. They found that higher reward sensitivity/BAS was associated with more severe weight cycling, but no association or moderating effect with EC was found. In a study concerning the role of temperamental factors in binge eating in obese patients, patients with regular binge eating reported a significantly lower level of EC compared with patients without binge eating [63]. Interestingly, the binge eating group did not show lower BIS and/or higher BAS scores (reactive temperament), both related to more impulsivity. The study of Turner et al. [68] identified 3 distinct groups of ED patients based on measures of reactive temperament and EC: an overcontrolled/inhibited group (high BIS, low BAS, moderate EC), an undercontrolled/dysregulated group (high BAS, moderate BAS, low EC), and a resilient group (high EC, moderate BAS, low BIS). Patients in the undercontrolled/dysregulated group demonstrated more severe symptoms of bulimia, hostility and Cluster B Personality Disorders compared to the other groups.

In a recent study within a community sample of adolescents (14–19 years), Matton et al. [69] examined the moderating role of EC in the association between sensitivity to punishment and sensitivity to reward and the eating styles restrained eating, emotional eating, and external eating as possible eating disorder precursor. Although some evidence was found for an interaction with EC in girls, main effects in both boys and girls were found for sensitivity to punishment and sensitivity to reward. Müller et al. [70] distinguished two temperament subtypes in a sample of treatment-seeking obese individuals (a cluster high in EC and low in punishment and reward sensitivity (reactivity) and a cluster low in EC and high in punishment and reward sensitivity). In the cluster low in EC, more co-morbid psychopathology (ADHD, binge eating, and depressive symptoms) was found.

A vulnerability to disinhibition also seems to be a core risk factor associated with both the initiation and continuation of SUD [71]. Two neural systems are involved: one involving EC, localized in prefrontal cortical circuitry, and one involving incentive reactivity (reward sensitivity), localized in subcortical circuitry [26]. In a recent study, Santens et al. [72] combined measures of reactive and regulative measures to establish subgroups of adult inpatients with SUDs and could identify a “resilient” group (high EC, low BAS, low BIS), an “anxious” group (low EC, high BIS, moderate BAS), and a “reward-sensitive” group (moderate EC, high BAS, moderate to low BIS). The “anxious” group had the highest levels of clinical symptomatology.

In a longitudinal study that was part of a larger interventional study, Piehler et al. [73] found that higher levels of EC in adolescence (n = 998) were related to less problematic substance use in early adulthood (tobacco and marihuana). Although this effect was not significant for alcohol use, the interaction between EC and exposure to a “substance use lifestyle” was significant for problematic alcohol use in early adulthood. In another study in undergraduates, Wong and Rowland [74] examined the relationship between two motivational orientations (autonomy and controlled orientations within the Self-Determination Theory of Ryan and Deci [75, 76]), the role of EC and substance use among students. Autonomy orientation, also called intrinsic motivation, positively predicted EC, which was associated with a decrease in the expected frequency of drinking. In contrast, controlled orientation negatively predicted EC, which was associated with an increase in the expected frequency of drinking. Controlled orientation or extrinsic motivation also significantly predicted the presence of alcohol-related problems and illicit drug use via EC. Overall, although no main effect was reported, EC significantly mediated the effects of autonomy orientation and controlled orientation on frequency of alcohol use. In another recent study by Walters et al. [77] in 196 young adults, EC was not significantly associated with alcohol consumption. In addition, in a study by the same group, EC exhibited a protective effect, reducing the effects of alcohol intoxication on the likelihood of unprotected intercourse [78]. In a large (n = 188) study among university students, Kahn et al. [79] investigated whether components of EC serve unique roles in moderating the link between reward and punishment sensitivity and substance use behaviors. In this study of emerging adults, inhibitory control (ATQ measured) was the only component of EC that emerged as a significant moderator.

Different studies explored the effect of early family context or a family history of SUD on the risk for developing substance use problems. In a longitudinal study (from age 11 to 27), Mun et al. [80] found that higher levels of adolescent EC were associated with lower problematic substance use.

In their sample of 277 families, Adkison et al. [81] used only behavioral tasks to measure EC (Stroop task, Stop-Go Task, Tower of London). Their results indicate that especially sons of fathers with an alcohol problem have lower levels of EC which makes them particularly vulnerable to poor self-regulatory strategies.

Taken together, the majority of studies exploring the relationship between EC and substance use support the hypothesis that lack of EC is associated with an increased risk for the development of addictive behaviors. However, findings are not consistent, and none of the studies we found included patients with SUD.

In the etiology of ADHD, both neurocognitive and temperamental factors have been implicated. However, studies on EC within adult ADHD remain remarkably scarce within the timeframe 2008 and 2018.

Within a large student sample, Graziano et al. [82] showed an association between the severity of ADHD symptoms and risky behavior but only when EC was low. However, it needs to be noted that this study relates to ADHD symptoms (as assessed with a screening instrument) and not to individuals with a formal ADHD diagnosis.

In another study, Burden et al. [83] assessed response inhibition in a sample of young adults diagnosed with ADHD by studying Event Related Potentials (ERP) during a classic Go/No-Go task. In terms of behavioral performance, poorer inhibitory control was evident in participants with childhood ADHD both with and without prenatal alcohol exposure, as reflected in poorer accuracy when attempting to withhold the button press to No-Go. Analysis of the ERPs revealed a markedly diminished P3 difference between No-Go and Go in the young adults with a history of ADHD but no prenatal alcohol exposure (the idiopathic ADHD group). In a study using ERP deviations of electrophysiological measures, Marquardt et al. [84] suggested reduced effortful engagement of attentional and error-monitoring processes in adults with ADHD. Associations between ADHD symptom scores, event-related potential amplitudes, and poorer task performance in the ADHD group further support this notion.

Given the recent increase of interest in behavioral addictions, we decided to include a broader spectrum of behavioral addictive patterns than currently included in the DSM or ICD classification [85].

As several studies showed an association between EC and CIU and CB, Claes et al. [63] investigated the relationship between CB and CIU in a sample of 60 patients with an ED. They found a significant association between CB and CIU. Concerning reactive temperament, they could not find a significant association between CB/CIU and BIS, but CIU was significantly related to BAS drive and CB almost significantly positively related to BAS fun seeking. Concerning regulative temperament, both CB and CIU were characterized by lack of EC, more specifically by low levels of inhibitory control. In a sample of CB outpatients, however, Müller et al. [86] surprisingly found no association between low EC an CB. They found an association between BAS, high materialism and especially depression scores. Claes et al. [87] found on the other hand in a sample of female patients with an eating disorder a positive correlation between low level of EC and CB.

In CB, a deficit in SR might also be a potential risk factor. Therefore, temperamental features are thought to be underlying factors associated with CB. In a small study, Voth et al. [88] investigated reactive and regulative temperament in a sample of treatment seeking CB patients combining temperament questionnaires and performance-based tasks. In the CB group, they found lower levels of EC (regulative temperament) and higher levels of BIS and BAS (reactive temperament) in comparison with the control group. The CB group performed worse on the Iowa Gambling Task (IGT) [89] compared to the control group, which suggests a tendency toward disadvantageous decisions and a higher sensitivity to immediate reward in the CB-group that may reflect higher BAS-reactivity. In the Stroop task, no group differences could be found. They found no significant associations between the questionnaire-based results and the outcomes of the behavioral tasks.

Despite the known relevance of attentional impairments in psychotic patients [90], no studies were identified using measures for EC in psychotic patient samples.

In the PubMed search, we did not find studies of OCD.

According to Gray’s personality model, OCD is defined as an anxiety problem driven by the BIS in combination with a lack of attentional control (subscale of EC) [91].

Our literature search yielded 31 studies covering different clinical disorders. Most frequently studied in consecutive order were mood and anxiety, substance use, and ED. Very few studies were found on adult ADHD and none in patients with psychotic disorders. Overall, the results of the included studies point to a role of EC in the pathogenesis of psychiatric disorders. The role of EC was different throughout different studies, i.e. EC as a main effect, as a moderator or as a mediator. Based on these findings, EC seems to confirm its transdiagnostic dimension cutting through both internalizing and externalizing disorder categories. However, caution should be taken in interpretation. By far most of the studies were performed within non-pathological student samples, exploring relations with disorder symptoms – not disorders. Very few studies included individuals with diagnosed disorders.

EC has been identified as a contributor to both adaptive and adverse outcomes in children, adolescents, and adults and this across many domains. EC seems to affect maladjustment by contributing to the processing of information, as well as to the modulation of emotion and behavior. The ability to divert attention from negative thoughts and to focus on affectively neutral or positive thoughts and activities, for example, seems to be important to experience less negative emotion and has been linked to low levels of anger, anxiety, and depression [92-94]. Engaging in a new activity or focusing on new stimuli appears to reduce distress [95, 96]. The ability to focus attention is also likely to aid in planning behavior, and can help to deal with stressful situations. Attentional control may be especially important for reducing internalizing symptoms such as sadness and anxiety. In addition, the ability to effortfully inhibit behavioral impulses is important for reducing externalizing problems [97, 98]. Although it would be interesting to distinguish between the three components of EC (attentional control, inhibitory control, and activation control) in both internalizing and externalizing disorders, in most studies, however, the total sum of EC is used since the general concept of EC is of interest [27] and the alpha coefficients of the subscales are often too low, indicating that they are less reliable than the total score [28]. We only found three studies where analyses were made with the three subcomponents of the EC [23, 79, 87].

How EC deficits contribute to the different pathogenic processes remains to be understood, with some studies indicating a more direct causal relation and others with EC as a mediator factor modifying the effect of other vulnerabilities. Likewise, its role with regard to specific psychopathology versus a common factor influencing severity and chronification of different disorders remains to be explored.

Although not the topic of the current study, the role of EC in the pathogenesis of PD, increasingly, is highlighted. Claes et al. [11] investigated the association of both reactive and regulative (EC) temperament with PD and found that all PD were characterized by low levels of EC, cluster C PD by high BIS and cluster B PD by high BAS. For several PD, BIS and EC interacted: BIS was only related to severe PD pathology if EC was low. Another study found low EC in relation to borderline PD [99]. In an earlier study, De Panfilis et al. [100] showed a specific role for EC as a mediator between rejection sensitivity and its subsequent interpersonal distress on borderline personality features in an adult community sample, suggesting that low SR capacities may enhance interpersonal distress in response to rejection.

The construct of EC based on Rothbart’s temperament model is the same across the different studies. Only assessment methods of EC differed especially concerning the performance-based tasks, while only the ATQ-EC was used as questionnaire. EC can be measured by self-report questionnaires and behavioral/neurocognitive tasks. In the studies cited above, however, the authors concluded that no significant associations could be found between personality (temperament questionnaire) and neuropsychological measures of executive/reactive inhibition [23, 70]. This is in line with the overall findings within the neuropsychological literature indicating that questionnaires and behavioral tasks do not measure the same underlying construct and therefore should not be used interchangeably [23]. Given that many studies included in this review were done within (large) student samples, most of them used mainly self-report scales, i.e. with the ATQ-EC as most prominent. As to the behavioral measures different tasks were used which are characteristically used within the study of inhibitory processes, e.g. Stroop or SST. However, it can be questioned whether these tasks are specifically mapping EC or other dimensions. This question relates to another, i.e. the exact nature or definition of EC and how it differentiates from executive control. Taken together, measuring EC falls into the same limitations that are also prominent in other neuropsychological dimensions. Both the conceptual unity and the use of different instruments highlight the need for a consensus definition and subsequent standardized measuring method highly needed to allow for comparison of findings over different studies.

EC has been largely understudied in adults compared with the neuropsychological research on executive functioning. Some authors, however, call for an integrated model of SR combining the temperament framework using measures of “effortful control” and the “executive function” framework given the conceptual and empirical overlap between EC and executive functioning [16, 18, 49, 101]. Nigg [17] also states that executive functioning, EC, and cognitive control are closely related. Working memory is also part of or closely related to EC [17, 18] possibly due to shared involvement of executive attention. Bridgett et al. [16] also showed that EC is related to the executive function of updating/monitoring information in working memory. They also found that high EC and better updating/monitoring information in working memory were linked to lower dispositional negative affect.

Research further shows that poor effortful/cognitive control is significantly related to reduced structural and neural activity in prefrontal cortices [102], whereby this reduced activity in the PFC correlates with various psychiatric disorders [103]. These findings are consistent with recent neurobiological studies that identified a common neural circuit disruption in cognitive control across psychiatric disorders [104, 105]. The findings of these studies demonstrate a common pattern of disruption across major psychiatric disorders that parallels the “multiple-demand network” observed in intact cognition [104, 105]. The authors suggest that neuropsychological performance, gray matter volume, and functional brain activation converge to implicate transdiagnostic disruptions in neurocircuitries underlying general cognitive capacity.

Many limitations should be taken into account with regard to the interpretation of the results. First of all, we based our search on one database (PubMed). Although we think this is a valid choice given our focus on EC and psychiatric disorders, the use of additional databases might provide a more comprehensive overview. The current work thus cannot be considered as a systematic review but as an exploration of the possible role of EC throughout different diagnostic categories. Second, despite a large number of studies within student and healthy control groups, the paucity of studies focusing on psychiatric disorders in adult individuals is striking. So, findings from these student samples should be very carefully used when reflecting adult psychopathology. Further, we found no study comparing patient groups with different disorders (or temperaments). Most studies are highlighting differences between patient groups and HC. However, exploring differences between targeted patient groups may yield important additional information on the role of EC dimension in the pathogenesis of different disorders. Finally, throughout different studies different conceptualizations for EC are used and often overlap with constructs that are also used in other constructs, i.e. executive functioning. A better delineation between the different neuropsychological constructs and their assessment methods is badly needed to further explore the details and subtleties of the underlying mechanisms in psychopathology [17, 106].

Taken together, the concept of EC can be seen as a universal psychological dimension covering a continuum from normality to psychopathology and this across disease categories. We found indications that EC is an important psychological dimension within adult psychopathology, cutting through the boundaries of both internalizing and externalizing diagnostic categories. Its role may be both directly causal or as a mediator factor influencing severity and prognosis of a specific disorder. Early assessment of EC and early interventions to improve EC might help to avoid or decrease the risk on developing a broad spectrum of psychiatric disorders.

The authors have no ethical conflicts to disclose.

The authors have no conflicts of interest to declare.

There is no funding for this study.

Santens E. performed a literature search in the database PubMed, extracted relevant data and provided summaries of the research studies. Santens E. wrote the first draft of the manuscript, and all authors contributed to and have approved the final manuscript.