Delay gratification ability biases motivation for delayed rewards via cortico-striatal network
Poster No:
767
Submission Type:
Abstract Submission
Authors:
Yang Xu1, Yachao Rong1, Ping Wei1
Institutions:
1School of Psychology, Capital Normal University, Beijing, China
First Author:
Co-Author(s):
Introduction:
Pursuing rewards is essential for human survival and reproduction, prompting individuals to adjust behaviors in their pursuit. However, when the expected delivery of rewards is delayed, task performance declines with blunted neural activities [1], posing a real-world challenge. As the Expected Value of Control (EVC) theory [2] predicts, the discounted value of delayed-reward (DR) compared to immediate-reward (IR) may lead to declined performance for DR. Individual's delay gratification tendency plays a key role in forming the value of DR vs. IR. While existing research has pinpointed this possibility, the underlying neural mechanisms are not revealed [3]. In this study, we aim to employ fMRI to elucidate the neural mechanisms underlying the impact of delay gratification on pursuing delayed rewards.
Methods:
50 participants (48 remained after exclusion, 19 female, M=23) were recruited to finish a modified Monetary Incentive Delay (MID) task in fMRI scanner, and to complete a delay discounting task (DDT) post-scan. In the MID task, participants were required to discriminate the color of a circle after a reward cue indicating potential reward (IR, DR, or no-reward). Then, the response-contingent feedback was displayed to indicate the reward outcome. The monetary reward gained in the IR condition was cashed out immediately after the experiment, while the reward gained in the DR condition was paid out three months later. After that, participants finished a DDT whose data were fit using a hyperbolic discounting model, serving as a measure of delay gratification ability (i.e., logk). For the neural data, our focus centered on the reward anticipation phase of contrast IR vs. DR within three a priori defined regions of interest (ROIs): the ventral striatum (VS), dorsal anterior cingulate cortex (dACC), and anterior insula (AI). Brain-behavior correlations and mediation analysis were conducted to unveil whether these regions underpin the process of biasing motivation differentially for IR and DR, driven by delay gratification. Additionally, dynamic causal modeling (DCM) was employed to elucidate how these ROIs interacted to transform cue value into motivation for getting corresponding rewards. Finally, multivariate pattern analysis (MVPA), including classification and support vector regression (SVR), and inter-subject representational analysis (IS-RSA) were conducted to provide complementary evidence regarding how delay gratification ability biases motivation for DR vs. IR.
Results:
The reaction times revealed a hierarchical pattern (IR < DR < NR). Brain-behavior correlation and mediation analyses revealed that VS, dACC, and AI mediated the link between delay gratification and RT (DR vs. IR). DCM analysis further identified a model with full recurrent connectivities between these ROIs, with inputs originating in AI. Notably, contrasting IR vs. DR in cue-related inputs correlated with activities in these ROIs, as well as with RTs and marginally with logk. MVPA demonstrated that neural patterns within these ROIs could decode IR vs. DR reward anticipation, with decoding accuracy of dACC and AI varying based on logk. Lastly, using SVR and IS-RSA, we found VS carried over the information of individual logk. Taken together, delay gratification modified the neural activities within the cortico-striatal network, thereby biasing the motivation in pursuit of DR as compared to IR.
Conclusions:
Motivation in pursuit of delayed rewards is decreased as compared to immediate reward. Individual's delay gratification ability determines value representation for delayed reward compared to immediate reward, and biases motivation for such rewards through the cortico-striatal network. These findings not only contribute to our understanding of the impact of delayed-reward delivery on motivation but also extends the EVC theory to cases where reward delivery is delayed.
Emotion, Motivation and Social Neuroscience:
Reward and Punishment 1
Higher Cognitive Functions:
Executive Function, Cognitive Control and Decision Making 2
Keywords:
FUNCTIONAL MRI
Multivariate
Other - delay gratification; reward anticipation; dynamic causal modeling; representational analysis
1|2Indicates the priority used for review
Provide references using author date format
[2] Shenhav, A. (2013). "The Expected Value of Control: An Integrative Theory of Anterior Cingulate Cortex Function." Neuron 79(2): 217-240.
[3] Lee, N. C. (2012). "Academic motivation mediates the influence of temporal discounting on academic achievement during adolescence." Trends in Neuroscience and Education 1(1): 43-48.