Motivation and emotion/Book/2023/Episodic future thinking and delay discounting

Overview

 * Case Study:

Imagine a girl named Leslie who attends a late-night party with her friends on a Friday night (see Figure 1). Someone walks towards her and offers her an alcoholic drink. Leslie thinks that there is no harm in accepting it for one night. She sees everyone around her having a good time and begins to say yes. Then Leslie starts to think about the future. She thinks about the consequences of drinking too much and realises that she has work in the morning. Then she remembers the last she had a drink and how sick she felt after. Leslie’s muscles are starting to get tense, and her stomach feels uneasy. Her heart is beating faster, and she decides against it. In this scenario Leslie thought about the future and decided not to drink alcohol on that night. Thinking about work and her personal health shaped her decision in this scenario.



Every day that people open their eyes, they make hundreds of decisions about their life. They make choices about what to do in the day, the time they spend with their friends and family, where they want to live, and what they want to learn. The ability to imagine future events is called episodic future thinking (Chang & Ladd, 2022). It allows people to process future experiences. This allows people to simulate the emotions they would be experiencing, the circumstances that they could be facing, and the autobiographical details of their life (Lin & Epstein, 2013) It enables people to think about future events and make decisions that have many effects on their life. People actively engage in episodic thinking day-to-day. For example, a person might start to think about meeting up with their friend. They might imagine the things that will happen, and what they will say, based on previous experiences. Another person who tends to procrastinate, may start working on an assignment thinking about the ramifications of handing in an assignment late.

The decisions that people make on a day-to-day basis can have a big impact on their health and wellbeing. Previous research has investigated whether episodic future thinking can be utilised to support people. Studies have examined the link between episodic future thinking and delay discounting. Delay discounting occurs when people tend to choose immediate rewards over long-term benefits. For example, a person might choose eating a piece of cake over a well-nourishing breakfast because of the immediate energy they get from the sugar in the cake.

This chapter looks at the link between episodic future thinking and delay discounting, and whether it can be utilised to support people’s health and wellbeing.


 * Focus questions:


 * What is episodic future thinking?
 * What is delay discounting?
 * How are episodic future thinking and delay discounting related?
 * How can the link between episodic future thinking and delay discounting be used to support people’s health and wellbeing?

Episodic Future Thinking
Episodic future thinking refers to an individual’s capacity to imagine and simulate their own personal future. People differentiate between varying kinds of future thinking. Shacter, Benoit, and Szpunar (2018) identify four different types:
 * 1) Simulation refers to an individuals ability to create mental representations of what the future will look in their head.
 * 2) Prediction refers to a person’s ability to make estimations of how likely a future event will occur.
 * 3) Intention refers to an individual’s ability to set goals for the future.
 * 4) Planning refers a person’s ability to create steps that they need to take to achieve their goals.

Research surrounding episodic future thinking generally focuses on the simulation and construction of future events. When people daydream about what the future will look like, they are engaging in episodic simulation. It is distinctive as it allows people to live through possible future events and feel the emotions, they anticipate with it (Rosh, Stramaccia & Benoit, 2022).

Functions of Episodic Future Thinking
According to Shacter, Benoit, and Szpunar (2018), research has indicated that episodic future thinking has several functions. It supports people with planning, emotion regulation, and decision making. It also plays a role in shaping a person’s sense of identity. The focus of this book chapter is the impact that episodic future thinking has on decision making. The effect of future thinking is clear in studies where people make decisions between two rewards that contrast in terms of their magnitude and proximity.

Take the example of someone who is suffering from diabetes. The doctor has suggested that they eat less sugar to increase their health. Eating healthier has many benefits, such as lowering the risk of heart disease, better kidney function, and improved mental health. However, these are long-term improvements. As rewards become more distant, there value is diminished. This is known as temporal discounting. This means that making short-sighted decisions such as eating a big block of chocolate is easier. Yet, when people think about bigger rewards, and how their life will look in the future, they become more patient and think about long-term goals. This shifts their attention.

Cognitive Mechanisms
Research suggests that there is a link between episodic memory and episodic future thinking. The episodic memory system allows people to recall their memories. According to the constructive episodic simulation hypothesis episodic future thinking occurs when pieces of past experiences are recombined to simulate events that may occur in the future (Shacter, Benoit, and Szpunar, 2018). In other words, the construction of future events is in part based on the recollection of past events. Another theory known as the semantic scaffolding hypothesis also suggests that semantic memory guides episodic future thinking, based on impairments seen in patients with semantic dementia, who exhibit difficulties imagining future events. Although the exact mechanisms that govern episodic thinking and episodic future thinking are unclear, research has suggested that there is a connection between these two distinct types of cognition.

Episodic memory and Episodic future thinking share similar characteristics and develop similarly across the lifespan (Rosh, Stramaccia & Benoit, 2022). Rosh, Stramaccia and Benoit (2022) suggest that lesions in the medial temporal lobes that affect episodic memory, also cause impairments to episodic future thinking. Neuroimaging studies suggest that there is a common network of brain regions that increase in activity when imagining future events or recollecting past events. Taken together this suggests that episodic future thinking relies on the episodic memory system.

Neural Mechanisms


The network of brain regions involved in episodic memory and episodic future thinking includes the posterior cingulate, medial temporal lobe, medial prefrontal cortex, and parietal and lateral temporal regions. The correspond with the default network. FMRI studies suggest that different brain regions are involved depending on what type of stimuli is being processed (Shacter, Benoit, and Szpunar, 2018). The means that different brain regions are active when processing objects, people, or locations. Previous research also suggests a strong link between hippocampal activity and the simulation of future events (Shacter, Benoit, and Szpunar, 2018). Evidence from an FMRI study also suggests that that the hippocampus mediates the effects of simulation on temporal discounting (see figure 2). Neuropsychological studies on patients with amnesia show that patients with damage to the hippocampus face difficulties imagining future events. However, results are not consistent across all patients with amnesia. This suggests that different subregions of the hippocampus play a role in future thinking. Lastly studies have also suggested that the ventromedial frontal cortex plays a role in future thinking. It allows people to access schematic knowledge.

Delay Discounting
Delay discounting refers to an individual’s preference to select short-term rewards over long-term rewards. It can be defined as an individual’s capacity to engage in delayed gratification. Odum et al. (2020) suggests that high levels of delay discounting have been connected to maladaptive behaviours that may be rewarding in the short-term but have negative consequences in the long-term.

Take the example of a person who continually procrastinates before studying for an exam. Every time that they think about revising their notes, they get distracted by other things in their life. They go out to spend time with their friends, fill their time doing chores, or watch movies that they find online. When the exam finally comes, they decide to cheat thinking about the benefits of avoiding a bad score. They act impulsively as opposed to imagining the consequences of cheating. They also do not consider the long-term benefits of learning through hard work and interest.

Delay discounting is a behavioural marker for addictions (Chang & Ladd, 2022). It has been associated with addictive behaviours such as substance use and gambling (Lin & Epstein, 2013). Research suggests that non-monetary rewards such as drugs, alcohol, food, and health are more steeply discounted then money (Odum et al., 2020). Although some authors talk about the tendency for individuals to delay discount, Da Matta, Goncalves, and Bizarro (2012) highlight that delay discounting changes in individuals depending on the environment, or pharmacological condition that it is taking place in. They suggest that it is important to think about it as a behavioural tendency rather than a fixed trait. Other studies highlight that delay discounting has trait like qualities, as people who discount monetary rewards also also likely to discount non-monetary rewards (Odum et al., 2020).

Neural Mechanisms
Delay discounting is connected to self-regulation and is characterised by making impulsive decisions (Gollner et al., 2017). Previous research has suggested that when rewards are readily available in sight, the ventral striatum, medial orbitofrontal cortex and medial prefrontal cortex regions of the brain become active.

In an fMRI study, Waegeman et al., (2014) investigated what areas of the brain are active when someone chooses to delay an immediate reward in contrast to when someone chooses to make an impulsive decision. Forty-one 18–21-year-old males participated in the study. During the task, participants were asked to make a decision between two monetary rewards. They were given the option to receive a smaller, but more immediate sum of or money, or wait to gain a larger but more distant amount of money. The results indicated that waiting for long-term rewards was associated with activation in the dorsolateral prefrontal cortex. When participants who chose to wait were making their decisions, the inferior frontal gyrus, dorsolateral prefrontal cortex, and medial prefrontal areas of the brain were active. Participants who acted more impulsively showed activation in the medial prefrontal cortex.

The Relationship Between Episodic Future Thinking and Delay Discounting
Studies have investigated whether episodic future thinking can be used to decrease delay discounting, by impacting the decisions that people make. Research suggests that when people experience financial hardship or severe levels of stress, their tendency to delay discount increases (Epstein et al., 2021). This means that they have a stronger focus on the present moment and may not think be able to think about long-term and secure goals. Take the example of someone who has recently lost their job and is struggling to pay their bills. Borrowing money is not a long-term solution to their problems, however it allows them to cope with their daily life. Focusing on immediate needs is an adaptive response, however in the long-term delay discounting can lead to various unhealthy behaviours. It has also been associated with risky behaviours such as neglecting the use of seatbelts, disregarding the use of sunscreen, and avoiding dental examinations (Hollis-Hansen et al, 2019). However, when people think about the future, they consider the different directions their decisions will take their life in. This allows people to think about future goals.

Features of Episodic Future Thinking that Lead to Long-term Decisions
There are various factors that influence the effectiveness of episodic future thinking on delay discounting. One example is the valence of the future thinking (Rosh, Stramaccia & Benoit, 2022). When people are offered rewards that they will obtain in the future, they do not experience the same positive feelings as they would thinking about an immediate reward. It is by simulating and visiting that moment in the future that they experience positive emotions. Conversely experiencing negative emotions in the future is likely to devalue the future reward even more. Another consideration is the vividness of the future memory (Rosh, Stramaccia & Benoit, 2022). Vivid simulations evoke stronger emotions. It could also be that people are more likely to believe that a future event is likely to occur due to how vivid the simulation is. Inhibitory control and working memory may also enhance episodic memory retrieval to generate mental imagery (Lin & Epstein, 2014).

Another factor is the content specificity of the future event (Rosh, Stramaccia & Benoit, 2022). People are more likely to make far-sighted decisions if the simulation that they imagined is related to their future goals and rewards. Additionally, choice impulsivity is another factor influencing episodic future thinking (Rosh, Stramaccia & Benoit, 2022). People who tend to steeply delay discount rewards are more likely to disregard the future. Therefore, actively engaging in episodic future thinking should have a bigger impact on people who make impulsive decisions. This makes episodic future thinking relevant when thinking about people’s health and wellbeing. Especially, under the circumstance that it could support someone experiencing substance use or obesity.

Alcohol
Many people agree that there are times in life where it is important to be patient to achieve long-term goals and overcome challenges. For example, someone who drinks alcohol excessively may experience withdrawal when they try to stop drinking (see Figure 3). However, in the long-term they may experience advantages such as decreased risk of heart failure, lower blood pressure, and better health. Self-regulation plays a role in this (Gollner et al., 2017). Several studies have been conducted to see if episodic future thinking could be used as a cognitive strategy to support people to reduce alcohol consumption. Although evidence-based interventions for alcohol have existed for a long time, they are not always put into practice successfully. Looking for new interventions that support people consuming alcohol is an important area of research. Interventions based on episodic future thinking focus on expanding the temporal window of integrations. Therefore, they focus on increasing the time spent considering future outcomes and integrating that into present decisions (Athamneh et al., 2022). The concept that expanding the temporal window will result in less alcohol consumption is known as the reinforcer pathology theory (Athamneh et al., 2022).

A pilot study looking at using an academic-goal-relevant intervention provides preliminary evidence that episodic future thinking can be used as an intervention (Voss and Murphy, 2021). Participants consisted of university students and reported moderate decreases in alcohol consumption. Further research needs to establish the efficacy of this treatment. In another study Chang and Ladd (2022) studied whether the valence or content of imagined events influenced delay discounting. The results suggested that valence had no effect on delay discounting but found that content around professional work was connected to a decrease in steep delay discounting. The results suggest that professional goals influence far-sighted decisions in people who consume alcohol. In another study Snider et al (2018) investigated whether working memory training improved delay discounting. People suffering from alcohol dependence struggle with memory. They face deficits in planning and providing information on future events. This suggests that they may be confined within a narrow temporal window. The results of the study suggest that working memory training is able to improve the effects of episodic future thinking in participants who have a very small temporal window.

Cannabis
Similar to other substances, high levels of cannabis use is associated with delay discounting. Delay discounting generally decreases with effective treatment. Excessive cannabis use can lead to deficits in decision making and cognitive functioning (Sofis et al., 2021). There are no interventions that have been developed specifically to target delay discounting in cannabis use. People who use cannabis frequently experience difficulties in their episodic memory system. Taken together this suggests that cannabis users may benefit from episodic future thinking.

In a study Sofis et al (2021) prompted participants who had used cannabis to imagine positive future events surrounding different domains of their life. This included health, career, financial, leisure, and social domains. Effects of episodic future thinking showed a decrease in cannabis use. However, the effects of delay discounting was independent of this. Another web based study using episodic future thinking to target delay discounting in cannabis users also showed that the use of episodic future thinking may be beneficial for people who consume cannabis. The results showed that episodic future thinking supported people to decrease delay discounting and lower their cannabis use (Sofis et al., 2020).

Overall, this research provides initial evidence that cognitive strategies surrounding future thinking can be utilised to support people’s health and wellbeing. Further research needs to be done to understand the exact mechanisms surrounding the interaction between episodic future thinking and delay discounting to apply the findings clinically.

Exercise and Healthy Eating
Research surrounding episodic future thinking and delay discounting also focuses on exercise and healthy eating. Today obesity has a significant impact on people’s health and wellbeing. Although people intend to maintain health lifestyles, this can prove to be challenging over a period of time (Leahey et al., 2020).

Take the example of a person who has been suffering from obesity for a long time. Although they may have started by following a strict routine that included weekly exercises and healthy eating, after a month they feel that there has not been much change. They may start to experience difficulties staying motivated. In an article Leahey et al (2020) writes about the role of episodic future thinking and delay discounting on sustained behavioural change. The article speaks about whether this type of intervention can be used to support people in maintaining weight loss.

In another study, DeHart et al (2020) examined the difference between healthy behaviours in people who have a healthy weight and healthy behaviours in those who are obese. The study used a survey, monetary delay discounting task, and two measures of food valuation to collect data. The results suggested that individuals who are obese were not as likely to participate in as many health-related behaviours. The results indicated that these differences were mitigated by delay discounting. Despite this, another study looking at the effects of delay discounting on healthy eating noted that demand characteristics in the experiment design account at least partially for the beneficial effects of episodic future thinking on delay discounting (Rung & Madden, 2018). This suggests that more research needs to be done to identify the mechanisms of episodic future thinking to implement the research clinically.

Conclusion
Overall, previous research has investigated the link between episodic memory and delay discounting. Episodic future thinking refers to a person’s ability to imagine and simulate vivid future events. It is a cognitive function that supports people to make decisions day-to-day. Conversely, delay discounting refers to an individual’s tendency to choose short-term gains, over working towards long-term goals and benefits. Research suggests that it is maladaptive behaviour and behavioural marker for addictions. As a result, research has taken place to examine the role of delay discounting in risky behaviours. Studies have suggested that episodic future thinking is an effective way to reduce steep delay discounting. This book chapter examines it’s application towards supporting people with alcohol, cannabis, exercise, and healthy eating. Many studies indicate promising studies, however further research needs to take place to understand the underlying mechanisms of episodic future thinking and delay discounting before health interventions can be implements in a clinical setting.