Yan Yan Sze

Bleak Present, Bright Future: Online Episodic Future Thinking, Scarcity, Delay Discounting, and Food Demand

Obesity is associated with steep discounting of the future and increased food reinforcement. Episodic future thinking (EFT), a type of prospective thinking, has been observed to reduce delay discounting (DD) and improve dietary decision making. In contrast, negative income shock (i.e., abrupt transitions to poverty) has been shown to increase discounting and may worsen dietary decision making. Scalability of EFT training and protective effects of EFT against simulated negative income shock on DD and demand for food were assessed. In two experiments, we showed online-administered EFT reliably reduced DD. Furthermore, EFT reduced DD and demand for fast foods even when challenged by negative income shock. Our findings suggest EFT is a scalable intervention that has implications for improving public health by reducing discounting of the future and demand for high energy dense food.

Delay discounting and utility for money or weight loss: Discounting and utility

Obesity is related to a bias towards smaller immediate over larger delayed rewards. This bias is typically examined by studying single commodity discounting. However, weight loss often involves choices among multiple commodities. To our knowledge, no research has examined delay discounting of delayed weight loss compared with other commodities.

Less is more: Negative income shock increases immediate preference in cross commodity discounting and food demand

Negative income shock, or the rapid reduction in financial stability, has previously been shown to increase impulsive choice for money and demand for fast food. The interplay of these conditions for obesity is called reinforcer pathology. The present work examines the impact of negative income shock on monetary and fast food discounting using a cross-commodity delay discounting task and on purchasing of fast food and an alternative commodity. An obese sample (n = 120) was recruited from Amazon Mechanical Turk and assigned to read one of two narratives: negative income shock (n = 60) or control (n = 60). Participants then completed both within- and cross-commodity discounting tasks of money and food, and purchase tasks for fast food and bottled water. The negative income shock group demonstrated greater impulsive choice across discounting tasks, as well as higher intensity of demand for fast food but not for a non-caloric control commodity (bottled water). These results suggest that negative income shock increases preference for immediate reinforcement regardless of commodity type (money or fast food), but has specific effects increasing demand for particular commodities (fast food but not an alternative). In a reinforcer pathology framework, negative income shock increasing discounting of the future while increasing demand for fast food specifically represents a high-risk state for negative health behavior in obesity.