Impairments in self-regulatory behaviour seem to be involved in the development and maintenance of pathologic gambling and other addictive disorders.1,2
From a neuropsychological point of view, this impairment reflects a deficit in executive functioning and decision-making.3,4
Executive functioning includes functions such as cognitive flexibility (set-shifting), which is associated with orbitofrontal functioning, and working memory, planning and abstract thinking, which are associated with dorsolateral prefrontal functioning.5–7
However, decision-making seems to be mainly associated with activation of the ventromedial prefrontal cortex.5,8
People with pathologic gambling have shown impaired performance in tasks measuring both concepts. Specifically, studies report deficits in cognitive inhibition, complex executive functions and attention.9–11
This population also shows impairments in decision-making.12–14
Decision-making impairments are observed in impulsive individuals in general. Specifically, impulsive individuals show an insensitivity to variations in reward/loss magnitude of behavioural decision-making tasks.15,16
Sensitivity to reward has been the most studied aspect of decision-making. However, decision-making is also guided by sensitivity to punishment,17
which has received little attention in pathologic gambling, especially from a neurocognitive perspective.
Self-regulatory deficits may also manifest in certain personality traits such as impulsivity. Considering its multidimensionality, at least 2 types of impulsivity have been postulated: rash impulsiveness (acting rashly when distressed) and sensitivity to reward (greater response/activation to rewarding stimuli). The latter is based on Gray’s Behavioural Approach System.18
In the field of substance dependence, some authors consider rash impulsiveness to be a risk factor for uninhibited behaviour and for the progression from substance use to substance dependence, whereas sensitivity to reward is considered to be associated more with motivation to use substances than with substance dependence.19,20
However, there is confusion regarding some impulsivity-related terms that are not clearly classified into the previous 2-factor hypothesis. For instance, sensation-seeking (similar to novelty-seeking), which has been defined as a need for varied, novel and stimulating experiences,21
has been associated with heightened sensitivity to the rewarding effects of drugs.22,23
Sensation-seeking has also been associated with reward-seeking in animal studies,24
and it seems to be independent of rash impulsiveness.25
However, many studies of pathologic gambling use the terms impulsiveness and sensation-seeking indistinctly, and most of them report high levels of both traits in this population.26–28
Rash impulsiveness would represent a failure to inhibit a behaviour that may result in negative consequences, lack of reflection and planning, rapid decision-making and action and carelessness.29,30
Given the definition of both concepts (rash impulsiveness and sensation-seeking), sensation-seekers are not necessarily careless or nonreflective. As such, we should expect a stronger association between sensation-seeking and sensitivity to reward than sensation-seeking and rash impulsiveness.
The novelty-seeking factor of the Temperament and Character Inventory-Revised31
tool is considered to be a general measure of impulsivity. However, its different subscales seem to measure different components of this construct. Exploratory excitability (reflecting sensation-seeking) and extravagance (reflecting overspending behaviour and poor planning) have been related to polymorphisms in the dopamine (DA) D4 receptor (DRD4).32
These traits have been considered to represent the exploratory, extravagant and extroverted subtypes of the novelty-seeking factor. Conversely, the impulsive and monotony-avoiding subtypes would be represented by the impulsiveness (representing unreflective and careless behaviour) and the disorderliness (reflecting disorganized, uncontrolled, antinormative behaviour) subscales.32
The literature about the relation between Cloninger’s novelty-seeking subscales and the different components of impulsivity is scarce.33,34
Nevertheless, considering these findings in the framework of the previously mentioned 2-factor hypothesis, we may expect an association of exploratory excitability and extravagance with sensitivity to reward on the one hand, and impulsiveness and disorderliness with rash impulsiveness on the other. The distinction between these concepts and their association with self-regulatory deficits in pathologic gambling is understudied. Further, relatively few studies appear to have examined the relations between these traits and treatment outcome.
In spite of the importance of impulsivity in the generation and maintenance of pathologic gambling, the link between neuropsychological and personality (self-report) measures of impulsivity (as a whole) is relatively unexplored in the field of pathologic gambling. In addition, only 1 study has focused on the association of neuropsychological and personality measures of impulsivity with treatment outcome in pathologic gambling. Goudriaan and colleagues35
examined the effect of neuropsychological functions (disinhibition, perseveration for reward, cognitive flexibility, decision-making) and self-report measures of impulsivity and sensitivity to punishment on vulnerability to relapse after psychological treatment for pathologic gambling. They found that only disinhibition and perseveration for reward (as measured by neuropsychological tasks) were predictive of relapse at 1-year follow-up after treatment. No other neuropsychological predictors were identified, and no self-report measure was predictive of relapse. They concluded that neuropsychological measures, particularly disinhibition and perseveration for reward, are more powerful predictors of treatment outcome than personality measures. In this regard, Forbush and colleagues36
explored the predictive power of neuropsychological (general intellectual functioning, executive functioning, decision-making) versus personality (general personality and impulsivity) measures in a group with diagnosed pathologic gambling compared with healthy controls. They generated 2 neuropsychological factors and 2 personality factors (by factor analysis of the different measures) and used these converted variables as explanatory variables. In contrast to Goudriaan and colleagues,35
Forbush and colleagues36
found that personality measures were better predictors of a pathologic gambling diagnosis than neuropsychological functions. Both research groups used different outcome measures, but to our knowledge, only these 2 studies have addressed the specific role of neuropsychological and personality measures in pathologic gambling.
Differentiating the specific role of every measure may help clarify the mechanisms underlying problem gambling behaviour. Adinoff and colleagues37
concluded that the different behavioural manifestations of impulsivity may correspond to different neurocognitive constructs with specific neuroanatomical correlates. Then, impulsivity should be described not only in terms of phenotypes (as measured by self-report tests) but also from an endophenotypic/neuropsychological point of view. These authors recommend the study of the relation between impulsive behaviours, neurobiological impairments and risk of relapse in addictive disorders. Llewellyn38
also highlighted the importance of exploring the relation between neuropsychological measures of risk-related decision-making and personality traits.
In sum, very little research about the link between neurocognitive (endophenotypical) and self-report (exophenotypical) measures of both impulsivity and self-regulatory deficits has been done, particularly in the area of pathologic gambling. Second, the association between these constructs and treatment outcome in pathologic gambling has received little attention. In this context, we aimed to determine the relations between self-reported impulsivity, neurocognitive functions (executive functioning and decision-making, including both reward and punishment sensitivity) and treatment outcome (including both relapse and dropout) in pathologic gambling. Our specific objectives were, first, to establish the pattern of associations between neurocognitive variables and self-report (personality) measures of impulsivity in pathologic gambling and, second, to determine the predictive power of neuropsychological and personality measures in relation to relapse and dropout during psychological treatment for pathologic gambling.