About this srcd poster session

---

Panel information
Panel 1. Attention, Learning, Memory

Abstract

---

The ability to delay gratification plays a crucial role in fostering effective self-regulation, executive functioning, and adaptive social and behavioral development (Metcalfe & Mischel, 1999; Wilson et al., 2017). Demonstrating this ability at a young age has been shown to predict positive outcomes later in life, including academic achievement, social and emotional competencies (Ayduk et al., 2000), and long-term health and overall well-being (Bickel et al., 2014; Francis & Susman, 2009; Seeyave et al., 2009). Conversely, the inability to delay gratification is linked to poor academic performance and worse social and coping skills (Eisenberg et al., 2016; Mischel et al., 1988). We examined delay discounting in middle childhood in a sample of same-sex twins (514 children, 49% boys, mean age 8.94 years, 55% monozygotic), allowing for internal replication of the results and behavioral genetic analyses examining the heritability of delay of gratification at this age.

The Delay Discounting of Money task assesses children's capacity to delay immediate rewards in favor of larger future gains (Peper et al. 2013; 2018; Richards et al., 1999). In a computerized task, children could choose between a smaller amount of money available immediately or €10 after a delay. When a child selects immediate money, the subsequent immediate amount decreases, while if the delayed reward is chosen, the immediate amount on the next trial increases. Based on the "indifference points," the area under the discounting curve (AUC) is obtained (Myerson et al., 2001). A smaller AUC indicates faster discounting of delayed rewards, meaning that individuals are inclined to prefer smaller immediate rewards over larger delayed rewards. We also measured child IQ (WISC III; Wechsler et al., 1992), and parent-reported inhibitory control (TMCQ, Simonds et al., 2007).

Delay discounting was not related to gender, age, or family SES (see Table 2). It was, however, significantly correlated with IQ in child 2 (r = .15) but not in child 1 (r =.03), and with inhibitory control in child 1 (r = .13) but not in child 2 (r = .08). The correlation of delay discounting in MZ twins was r = .27. In DZ twins, the correlation was r = .02. The results of the likelihood ratio tests indicated that the variance and covariance of delay discounting were best explained by a combination of genetic factors (23%) and unique environmental factors (77%).

In the largest genome-wide association study to date, 12% of the variance in delay discounting was accounted for by genotype (Sanchez-Roige et al., 2018). The genetic signature overlapped with those of ADHD, schizophrenia, major depression, smoking, personality, cognition and body weight. Anokhin et al. (2011, 2015) revealed an increase in heritability estimates with age, from 30% at age 12 to 62% by age 18. However, heritability of delay discounting had not yet been demonstrated in middle childhood. Our results suggest that already in middle childhood delay discounting is influenced by genetic factors, which may be intertwined with (or facilitated by) associations with IQ and inhibitory control.

Author information

Author	Role
Marian J. Bakermans-Kranenburg, Ph.D., William James Center for Research ISPA - University Institute of Psychological, Social and Life Sciences, Lisbon	Presenting author
Ines Morais, William James Center for Research ISPA - University Institute of Psychological, Social and Life Sciences, Lisbon,	Non-presenting author
Manuela Verissimo, William James Center for Research ISPA - University Institute of Psychological, Social and Life Sciences, Lisbon,	Non-presenting author

⇦ Back to session