Some aspects of the cognitive components of temporarily myopic decisions can be explained in terms of working memory (WM). Thus, higher values of k are indicative of high levels of impulsivity. Greater willingness to wait for larger but delayed rewards (usually the indicator of a lower DD), has been associated with less impulsivity, better cognition and executive function. Higher rates of DD are found in subjects who are willing to decline greater rewards available in the near future, and that show a preference for smaller rewards available immediately. Smaller values of k indicate a lack of discounting and a preference for delayed rewards, while higher values indicate strong discounting and a preference for immediate rewards. \( V=\frac \) where D is the delay in the delivery of the reward, and k is a free parameter that describes the rate of discounting. The subjective value V of a reward can be estimated using the present value A of the delayed reward and is described mathematically as a hyperbolic curve with the following equation: Most studies using the DD paradigm characterize an individual’s choice by generating a discount function that models the effect of delay on subjective value of later rewards. Such decisions facilitate immediate choices but are impulsive and suboptimal in in the long-term, as the immediate results they lead to are overestimated compared to those deferred. For example, some people are likely to engage in temporary “myopic decisions” defined as the inability of individuals to realise that their action might implicate consequences. Individual differences that are likely to occur in DD explain important functional differences in decision-making. The DD task, in which one chooses between sooner/smaller or later/larger rewards, has proven useful in revealing deficits in executive functioning in various clinical groups. DD tasks involve a series of choices between receiving a small but faster (usually immediate) reward or a larger but delayed reward (DR). Delayed Discounting (DD) paradigms are the most used to study the process leading to a choice. In such studies, the attention has been focused on determining whether, in choices that may involve a short-term sacrifice for a long-term gain, the promptness with which a reward is obtained is perceived as an important factor in the process of decision-making. Psychological and economic studies consider ways in which gain, losses and probabilities are associated and combined to generate informed choices. The process of decision-making is based on the choice between alternative behaviours. Therefore, they are well suited to study the relations among neurodevelopment, delayed discounting and the larger executive functioning network subsiding decision making. Results are discussed in terms of the relation between working memory load and decision-making processes, their impact on impulsive behaviour in ADHD and the need for future research to understand possible neurocognitive correlates and use that information to develop better inclusive policies.ĭelayed Discounting (DD) refers to the human preference for smaller but quicker rewards rather than larger but delayed rewards due to the subjective devaluation of rewards as a function of the delay to their delivery.Ĭhildren with ADHD are characterized by elevated inattention, hyperactivity, and impulsivity, and more generally present differences in executive functioning, comprising an alteration of the reward processing networks and choice impulsivity. Furthermore, the memory load impact on frequency of immediate rewards was stronger in children with ADHD compared to typically developing children. ResultsĬompared to peers with typical development, delayed discounting was significantly stronger in children with ADHD and discounting rates increased in both groups for heavier memory loads. The experiment was conducted in a school setting. In the primary task the child has to choose between two different amounts of money at different time delays, while in the secondary task the child has to repeat a random series of digits with different lengths. Thirty-two children equally divided between typically developing and ADHD, from 8 to 10 years of age were assigned to sessions of a dual-task paradigm. A delayed discounting (DD) paradigm was used, comparing children with ADHD and age-matched controls. The aim of this study is to evaluate the effects of working memory load in impulsivity during decision-making processes. Deficits in working memory tasks have been widely documented in Attention Deficit Hyperactivity Disorder (ADHD) studies.
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