The Power of Habit In Decision Making
How to prevent going back to your old habits?
Posted November 5, 2018
How do we make decisions?
Roughly speaking, there are five steps to every decision. The first step involves representing the decision problem. We perceive a situation and construct an image of the decision problem. The second step requires the identification of the different courses of actions under consideration. The third step is the selection of one of the options on the basis of their valuations (determining which option is in our best interest).
The value that is assigned to an option might depend on internal states and the delay with which those payoffs occur. For example, the hunger level influences how much one assigns a value to food. For an addict who is craving their drug of choice, food or sex has little appeal. A person who devalues (discounts) too strongly will overemphasize near-term pleasures and underemphasize far-future costs. People generally devalue future health outcomes more when they are hungry than when they are sated.
The fourth step involves the execution and monitoring the desirability of the resulting outcomes. In the final step, the outcome evaluation is used to update the other processes to improve the quality of future decisions (learning). These steps are not rigid, and some steps may be performed simultaneously. For example, the option selection and valuation might be carried out simultaneously.
Most experts agree that step three (valuation) is the most important one. In general, there are three types of valuation systems: Pavlovian, habitual, and goal-directed system (Rangel, et al., 2008).
Pavlovian systems assign values to a small set of behaviors that are innate (‘hard-wired’) responses to specific cues, such as cues that predict the food reward. Rats and pigeons learn to approach lights that predict the delivery of food. Similarly, cues that predict a punishment or the presence of an aversive stimulus can lead to avoidance behaviors. If you come across a garter snake, you will perceive it as a “threat,” and will experience the urge to attack or jump. Any pet owners know that with sufficient training animals can learn to associate a response with a predictive stimulus.
The Pavlovian system is inflexible and unable to update its responses when they produce undesirable outcomes. A wide range of human behaviors might be controlled by Pavlovian systems, such as addiction, overeating in the presence of food, and behaviors displayed in people with obsessive-compulsive disorders (OCD).
Much of the time, people proceed by routine and habit. Examples of habits include a smoker’s desire to have a cigarette at particular times of day (e.g., after a meal).
The goal-directed mode of decision-making is similar to the rational choice framework, which considers decision-making as conscious and under volitional control. That is, a choice is a function of a deliberate intention formed by individuals on the basis of their evaluation of the expected consequences of that choice. An example of a goal-directed behavior is the decision what to eat at a new restaurant. The goal-directed system is flexible and updates its response when they produce undesirable outcomes. If you did not enjoy the food, you would avoid it in the future. This system exerts control over habits in light of new information.
How does the brain decide which valuation processes to use? We have the ability to shift our decision modes. However, the balance between these systems is susceptible to disruption by a range of factors, such as stress, working memory, and addiction (excessive habit-learning) (Gillan, et al., 2016).
Chronic stress is shown to affect the ability to shift decision modes. The stressed brain loses the ability to be reflective. Stressed people are prone to give in to their impulses (e.g., overeating, and alcohol use) as a way of coping with daily stress (Grant et al., 2011).
Working memory (WM) is defined as the ability to control attention, and distraction (e.g., irrelevant emails or text messages). For example, WM helps dieters to focus their attention and resist distraction. They have to remember and actively keep in mind their chosen goal. Working memory has limited capacity. Working memory can be temporarily impaired by anxiety or stress, craving, and alcohol intoxications. The impairment leaves us less able to control impulses.
Excessive habits in addiction are most likely a consequence of failures in goal-directed control over the action. For example, alcohol abuse can be explained by an imbalance between goal-directed and habitual processes (Stock, 2017). That is, the behavior is uncontrolled, and carried out in spite of adverse consequences. Furthermore, drug abuse may permanently damage frontal brain areas and thus diminish goal-directed behavior that can effectively keep their drug use habits in check.
The take-home message is that under certain circumstances, we are vulnerable to automatic bias, including cues and situations that trigger habitual behaviors. An essential component of most conventional therapies is to improve goal-directed cognitive control so that habitual behavioral can be overcome (Stock, 2017). Patients are instructed to replace the unwanted automatic behavior with another habit. The competing habit or response is to be carried out every time the urge to perform the initial unwanted habit appears.
Gillan CM, et al., (2016). The role of habit in compulsivity, Eur Neuropsychopharmacol; 26(5):828-40.
Grant, J. E., Donahue, C. B., & Odlaug, B. L. (2011). Overcoming Impulse Control Disorders: A Cognitive-Behavioral Therapy Program (Workbook). New York, NY: Oxford University Press.
Rangel A, Camerer C, Montague P (2008) A framework for studying the neurobiology of value-based decision making. Nat Rev Neurosci 9:545–556.
Stock AK. (2017). Barking up the Wrong Tree: Why and How We May Need to Revise Alcohol Addiction Therapy. Front Psychol. 2017 May 29;8:884.