# Motivation and emotion/Book/2024/Dopamine and decision making

* Multimedia presentation (3 min)

## Overview

* Imagine you have been offered a job promotion with increased salary, career development and greater benefits. However, this promotion is required for you to relocate to a different city. As you weigh the option, dopamine comes into the decision-making process. Maybe you have encountered a similar experience such as a job promotion which resulted in positives experiences. If you recall the memory being positive, dopamine is released giving a sense of excitement and anticipation of rewards. Or if the memory was more emotional, dopamine decreases leading to a more cautious mindset. Decisions such as accepting a job offer can be influenced by dopamine through our emotional regulation.
Dopamine plays an important role which can affect people's memory, motivation, behaviour and cognition. The topic of dopamine's effect on decision making has been studied to gain a better understanding. There are physiological and psychological aspects to dopamine which have been linked to mental disorders, however, key concepts such as dual process theory and motivation and incentive theory describe the underlying mechanisms of dopamine's role in the decision-making process. The theories that are presented in this chapter provide a greater understanding to how dopamine influences decision making and addresses the motivational implications.
From this chapter, you will understand what dopamine is, understand dopamine's influence on decision making, and read the theories which address dopamine's influence on our cognitive functioning.
* Focus questions:
* What is dopamine?
* How does dopamine relate to decision making?
* What has dopamine got to do with behaviour?
* What are the different theories surrounding dopamine?

## What is dopamine?

Dopamine is a chemical messenger, known as a neurotransmitter, working in the brain to help nerve cells transmit messages in the brain and the rest of the body. Dopamine plays a role in numerous body functions including: motivation, memory, attention and more (Health Direct Australia, 2023). The brain releases dopamine to contribute to feelings of pleasure and satisfaction as part of the reward system (Costa & Scheonbaum, 2022).
Dopamine is classed as a monoamine catecholamine neurotransmitter. Binding to the dopamine receptor and depending on the type of receptor, it has several different functions (Bhatia et al., 2024). Dopamine works by being packaged into vesicles by the vesicular monoamine transporter 2 (VMAT2) and then transported to cellular release sites. On release, dopamine is then capable of interacting with five G-protein receptor subtypes: D1, D2, D3, D4 and D5 (Costa & Scheonbaum, 2022).

### The Role of Dopamine

Dopamine's general role is to act on areas of the brain to give feelings of pleasure, satisfaction and motivation (Health Direct Australia, 2023). It signals to the brain as an action leads to a positive outcome to increase the chances of repeating the behaviour that increased dopamine levels. Dopamine is also responsible in the production of memory, mood, sleep and movement. The neurotransmitter is capable of influencing physiological responses as well psychological. For example, as dopamine releases, your body may experience a physiological response of an increased heart rate and heightened arousal, whereas lower dopamine levels may result in tremors in the hands.

### Dopamine Receptors

Dopamine receptors assist in daily life functioning. There are a total of 5 dopamine receptors which affect movement, emotion, and the reward system within the brain (Bhatia et al., 2024). As mentioned in the above text, the 5 dopamine receptors include D1, D2, D3, D4 and D5. Each receptor is found in a different location and has a specific function (See table 1 for receptor functions).
Table 1. The function of each type of dopamine receptor :
| Type | Function |
| D1 | memory, attention, impulse control, regulation of renal function, locomotion |
| D2 | locomotion, attention, sleep, memory, learning |
| D3 | cognition, impulse control, attention, sleep |
| D4 | cognition, memory, fear, impulse control, attention, sleep |
| D5 | decision making, cognition, attention, renin secretion |
The table above indicates each of the 5 dopamine receptors including their functions (Bhatia et al., 2024).

### Quiz
## How Does Dopamine Influence Decision Making?

Decision making is the process of choosing a course of action from a set of alternatives. As dopamine plays a significant role in several key [what?] functions, the neurotransmitter influences decision making through several mechanisms which include reward, risk assessment, motivation, and social factors[factual?]. Dopamine's role in decision making is quite complex. Rogers (2010) believes that dopamine's role in decision making is through the activity along mesolimbic, striatal and cortical pathways. Each of these are different pathways within the brain. It is also reported that the influence of dopamine and decision making is likely to involve interactions with other neurotransmitters including glutamate (Rogers, 2010). Dopamine is an important aspect in decisions making and its relation to the brain is well understood from various research[factual?]. Below you will discover further concepts explaining how the neurotransmitter factors into the process of decision making.

### Reward Anticipation

Reward anticipation is the cognitive and emotional process of predicting and preparing for potential rewards. Dopamine is closely linked to this concept and plays a key role in signaling the anticipation of rewards[factual?]. Dopamine levels will increase as individuals expect a positive outcome from a decision, enhancing motivation to pursue that choice[factual?]. Researchers have been able to provide evidence that dopamine connects to reward anticipation through dopamine transporter levels and brain activity (Dubol et al, 2018). Dopamine levels increase in specific areas of the brain, especially the striatum, to signal that a reward is desirable[factual?]. The interplay between dopamine and reward anticipation is essential for exploring human motivation and decision making.

### Risk Assessment

Risk assessment is the evaluation of potential outcomes through a decision, including both positive outcomes and negative consequences. The process of risk assessment is used in everyday decisions from financial choices, health choices, safety and other situations that include risk. Dopamine factors into risk assessment due to its involvement in prediction and evaluating rewards[factual?]. Dopamine is associated with the brain's reward system which processes judgments regarding risk[factual?]. As the brain assesses risk, dopamine levels increase in anticipation of a reward[factual?]. Lower dopamine levels cause an opposite effect in that a perceived risk may result in a more cautious approach in a presented situation (Palm et al, 2014).
* Experimental study
* In 2014, Palm and colleagues conducted a study exploring risk assessment, risk taking behaviour and dopamine response in the dorsal striatum of rats. The aim of the study is to understand these behavioural traits predict dopamine release.
* The researchers assessed risk taking in rats by measuring responses from a decision-making task which required them to evaluate risk. The rats were then exposed to potassium and amphetamine to measure the resulting dopamine responses.
* Findings indicated rats of higher risk-taking behaviour had shown a significant dopamine response within the dorsal striatum. Those that were less prone to risk taking behaviours had a diminished dopamine response. The study suggests that individuals more inclined to risky behaviour may experience higher levels of dopamine.

### Social Factors

Dopamine factors into our social settings by shaping our perception, impacting emotions and making decisions. The neurotransmitter is capable of influencing how we may perceive social stimuli or how we interact with our peers. As dopamine plays a significant role in the brain's reward system, our brain will release dopamine as a response to a positive situation. When dopamine is released, it helps regulate learning, especially in social situation where people understand social norms and learn what is acceptable behaviour within groups. As dopamine contributes to cognition, this affects interpretation of social cues. Social conflict can decrease dopamine levels, while positive social experience can increase dopamine (Plaven-Sigray et al, 2014). So, depending on the levels of dopamine, this can influence decisions in social settings and effect how individuals behave. Perhaps give more examples on how dopamine influences decisions in social settings?

### Quiz
## Theories surrounding dopamine

[Provide more detail]

### Mental Health Issues

Mental health disorders can often alter how people think, feel and behave. It is important to understand the extent to which dopamine can influence certain mental disorders. [grammar?] Science behind dopamine levels have been linked to several different psychiatric disorders due to the different bodily functions that the neurotransmitter influences[factual?].
As dopamine is part of many different functions, having too much or too little is linked to disorders such as depression, schizophrenia and psychosis (Health Direct Australia, 2023). Depression is linked to a lack of serotonin, however, studies have found dopamine also contributes to a low mood. Mizuno et al (2023) had stated that dopamine transporter availability tends to be lower in those with depression, but dopamine receptors 2 and 3 are not altered for those with depression.
Dopamine can be linked to cases of schizophrenia. Evidence can suggest schizophrenia is associated with excessive stimulation of striatal dopamine receptors, inefficient prefrontal dopamine receptors and an alteration of prefrontal connectivity involving glutamate (Laruelle et al, 2006).

### Dual Process Theory

Dual process theory is a psychological framework that puts forward the existence of two systems through which humans think, make decisions and solve problems. The theory suggests that our cognitive processes are categorized into two types: system 1 and system 2. Both these systems operate on a different level which serves various functions to our thinking and decision-making ability (Barrouillet, 2011). This theory is able to highlight our cognitive processes and how it can lead to an efficient decision-making process in a familiar setting and potential biases or errors when relying too much on one's own intuition. Understanding dual process theory will provide valuable insights into human behaviour and highlighting instinctive and rational thinking into everyday lives.
System 1:
System 1 can be described as fast, high capacity, independent of working memory and cognitive ability (Evans, 2011). This system often operates with minimal effort and awareness. This system is primarily driven by emotional responses which is what allows individuals to make a quick judgment prior to an experience. In familiar situations, system 1 excels, enabling efficient decision making. Although, the automatic nature of this systems means it can sometimes be more analytical and deliberative thought processes that are crucial for addressing more complex problems (Evans, 2011).
* Example of system 1:
* Consider familiar patterns you come across on a computer. When you encounter a familiar "save" button, system 1 kicks in, allowing to click the button with little to no consideration at all. The automaticity is efficient, but it can lead to errors if the context has changed, such as the button performs as a different function in a new context.
System 2:
System 2 can be described as slow, low capacity, heavily dependent on working memory and related to individual differences in cognitive ability (Evans, 2011). Unlike system 1 which acts more automatically and intuitively, system 2 acts off conscious efforts and cognitive resources which allows individuals to evaluate, analyze situations, and make more reasoned decisions. When intuitive judgments fall short, this is where system 2 tends to activate. It overrides impulsive reactions and takes into consideration long term consequences from certain decisions. As system 2 demands a greater amount mental effort and can be less efficient, individuals can become more susceptible to cognitive fatigue (Evans, 2011).
* Example of system 2:
* Think about solving a complex math problem, such as calculating the cost of several discounted items you want to purchase. You sit down with pen and paper and carefully analyze the prices, apply the discounts in order and calculate the total. This process requires focus, concentration and you are actively engaging your analytical thinking.
Dopamine is associated with reward, motivation and pleasure and is crucial in how people assess and pursue rewards, influencing both system 1 and system 2. Dopamine interacts dual process theory by affecting the key cognitive functions and shaping the dynamics between intuitive and analytical thinking (Matzel & Sauce, 2023). When dopamine levels are elevated, individuals can be more inclined to choose an immediate reward over a delayed reward, reflecting impulsive behaviour. To delay that reward and impulsive behaviour, cognitive effort is required to appreciate the value of a delayed reward involving the reflective processing of system 2 (Soutschek & Tobler, 2023).

### Motivation and Incentive Theory

Incentive theory is one of the many psychological theories of motivation in which psychologists suggest human behaviour is motivated by outside reinforcers and internal forces. Some will argue that people feel motivated to do particular activities because of our internal desires (e.g., going out for a walk every day because it makes us feel better). Others will argue that out behaviours are driven from external rewards (e.g., going for a daily walk to win a prize). It is understood from this theory that individuals are motivated by rewards. Ellingsen and Johannesson (2008) suggest social and emotional factors such as concerns about fairness significantly influence how individuals respond to incentives. This highlights the argument that a comprehensive understanding of incentive theory must account for psychological and social aspects that affect motivation.
Dopamine is closely linked to motivation, driving individuals to engage in goal directed behaviour and pursue rewards. Motivation and incentive theory emphasize on [awkward expression?] the idea that higher dopamine levels tend to enhance motivation and the will to exert effort in pursuit of desired outcomes. Overall, dopamine is a key mediator in incentive theory due to motivational and behavioral outcomes[factual?]. The connection between this theory and the neurotransmitter is important when considering biological and psychological factors when taking motivation and incentives into deeper consideration.

### Quiz
## Conclusion

Dopamine is a key contributor when examining the underlying mechanisms of decision making. The neurotransmitter plays a crucial role within our brain to send messages throughout the rest of our body. The 5 receptors of dopamine which affect movement, emotion, and the reward system, all factor into the process of making decisions[grammar?]. Several important mechanisms of dopamine that influence decisions are risk assessment, reward anticipation and social factors. Each of these mechanisms relate back to dopamine as a strong influencer in the decision-making process. Key theories regarding dopamine consist of dual process theory and motivation and incentive theory. Both of these concepts create a psychological framework that further suggests how dopamine is capable of influencing our decisions and our motivation. Some research theorizes mental health issues such as depression and schizophrenia are linked to dopamine levels in the brain. As a result, poor mental functioning can impact the way individuals behave. In spite of any theories, the association between dopamine and decision making has been very well established in recent research.