Future Is Less Concrete than Now: Neural Predictor of Vividness Also Predicts Temporal Distance in Intertemporal Choice
Lee, S., Parthasarathi, T., & Kable, J. W.
Intertemporal choice – choice of smaller reward now versus a larger reward later – is one of the most heavily studied behaviors across a variety of disciplines. Why, however, are delayed outcomes less desirable? Two separate theories both suggest a common explanation: future outcomes are less concrete. Rick and Lowenstein (2008) pointed out that delayed outcomes tend to be less tangible than immediate outcomes (e.g., smoking now has immediately perceivable pleasure; the promise of better future health is less appreciable). In a similar vein, construal level theory (Trope & Liberman, 2010) proposes that when people think of future events, they use high-level construal to represent events in abstract ways, and for immediate events, they use low-level construal to represent them in a concrete manner. We tested these theories by creating whole-brain neural predictors of imagination vividness and imagination valence that are orthogonal to each other. These predictors were built using a dataset in which participants were instructed to imagine about vivid or non-vivid scenarios with positive or negative valence perfectly counterbalanced. In two separate Intertemporal choice datasets, we show that the whole brain neural predictor of imagination concreteness predicts the temporal distance to the delayed reward but not its amount. On the other hand, the predictors of imagination valence predicted subjective value of the delayed reward. The whole brain predictor of imagination concreteness recruited positive activations from central OFC and hippocampus with negative activations from precuneus. The predictor of imagination vividness recruited positive activations from vmPFC and PCC. These regions correspond well to previous neural evidence regarding construal level theory and subjective value respectively. These results suggest that people’s patience or impulsivity regarding delayed rewards may be modulated by how concrete a person perceives the delayed rewards to be.