Two systems of thinking: Why do rational people make irrational choices, and how can the answer help us better understand menopause?

  • Behavioral science indicates that people make decisions, including medication adherence decisions, using two systems of thinking: System 1, which is rapid but intuitive and biased, and System 2, which is rational and reflective but complex. Humans tend to favor System 1 thinking.
  • Understanding the human decision-making process allows for a better understanding of menopausal women.

People invoke many reasons to explain their medication non-adherence. Oftentimes, these explanations are based on some type of cost-benefit analysis. Behavioral science can shed light on how medication adherence decisions are made and how healthcare providers might influence such choices to better help their patients.

Rational “econs” and irrational humans do not have the same attitudes towards medication adherence

Until the 1960s, most social scientists worked on the premise that people are rational. They assumed that when given the same information, people will respond to it in essentially the same way. In the case of medication adherence, it was implied that if a physician prescribed life-saving drugs, any rational person, or “econ,”1 would adhere to the treatment diligently.

However, as per one study, approximately 50% patients suffering from chronic diseases, may be adherent.2,8 In the 1970s, the irrational nature of our decision-making processes began to be studied and categorized in detail. In fact, when presented with the same information, each person acts differently, according to her biases and perspectives. The decisions made can be perceived by others as irrational behavior; in such cases, econs are liable to act like irrational humans. Humans tend to believe their own behavior to be rational, even when rationalizing potentially self-harming behavior such as medication non-adherence.

In recent years, psychology and behavioral science as a whole have made significant advances in explaining how people make decisions. Notable among these advances was the work of 2002 Nobel Prize winner Daniel Kahneman, in conjunction with Amos Tversky, who explained that the human mind has two systems of thinking: System 1 and System 2. The former is fast and automatic, while the latter is slower and more deliberate4. Combined, these two systems govern people’s attitudes and behaviors.

The two systems of thinking: fast and slow

In his book “Thinking, Fast and Slow,” Kahneman explains the theory that people make decisions using two constructs: Systems 1 and 2. These systems are distinct and play separate roles in the decision- making process:

System 1 is immediate and automatic3,4,5. It can make assessments effortlessly and is responsible for generating rapid decisions. It allows people to perform actions without deploying an effort to think such as: determine the origin of a noise, detect hostility in a voice or on a face, drive a car in easy situations or even make intuitive decisions in complex situations for which a person is very well-trained. System 1 thinking is responsible for about 95% of all the decisions made over a person’s entire life.5

System 2 requires mental effort, attention, and concentration. System 2 can be considered a person’s rational and conscious self6. It allows people to structure complex information, reflect upon it, make rational choices, and deal with uncommon situations13. Kahneman describes System 2 as “lazy”7 because in most cases, it does not influence the decisions proposed by System 1. In other words, people tend to respond automatically to most events rather than employ System 2. Even when they do, System 2 may favor the conclusions of System 1. It is important to note that the “laziness” of System 2 is not hinged on cognitive ability.

Systems 1 and 2 interact quite successfully. System 2 is responsible for learning, which is a slow process and requires a great deal of mental effort. However, once System 2 stores general conclusions in one’s memory, these conclusions become the domain of System 1. Kahneman gives the example of a grandmaster chess player who has played tens of thousands of games and has formed the habit of analyzing chess piece positions4. For such a player, finding a strong move in a chess game can be effortless and is left to System 1. Conversely, a less experienced player would have to employ System 2 thinking to achieve the same goals. As another example, someone who uses imperial system can use System 1 to easily imagine a length of 5 feet, while someone from who uses metric system would have to use System 2 to convert feet into meters before their System 1 thinking could process the actual measurement.

To whatever extent possible, System 2 stores information learned through applied effort, which System 1 uses in its spontaneous interactions with new information from the environment.

What does our understanding of Systems 1 and 2 teach us about patients’ medication adherence?

In the treatment of chronic illnesses approximately 50% of patients do not take their medications as prescribed.8 In a separate cohort of of more than 22,000 post-acute coronary syndrome patients, 60% discontinued their statin medication within two years of hospitalization (non-persistence).9

As per a National Report Card on Medication Adherence, patients cited many different reasons for not adhering to treatment: forgetfulness, side effects, running out of medication, travelling, etc.11 While these may sound rational, they are typically indicative of conclusions based on System 1 reactions. System 1 constantly and involuntarily performs cost-benefit analyses; in this case, the effort required to take the drug (i.e. remembering to take it, dealing with side effects, etc.) is balanced against the benefits, which are often not immediate or apparent. This is especially true if symptoms are not evident, as with some chronic diseases that are asymptomatic much of the time.

A System 2 reaction, which an econ would embrace, is a rational consideration of the dangers of not properly completing a chronic disease treatment. However, because System 2 is lazy and requires effort to operate, irrational humans tend to use shortcuts in the form of System 1 heuristics that allow quick decisions made with the least amount of effort. Such heuristics include things like snap decisions, choices based on insufficient data, and poor risk assessment. These decision-making processes can yield very poor choice, such as the decision not to adhere to medical treatment.

Patients process information and behave based on narrative understanding

Kahneman described the mind as a “machine for jumping to conclusions.”10 According to Kahneman, evolution has led us to develop a “narrative understanding” of our environments based on available data. The amount and quality of data are irrelevant to System 1, which generates the easiest cognitive conclusion possible according to the existing narrative. For example, suppose a patient with post- menopausal syndrome is asked the following question: “Do you want Dr. Brown to be your doctor? He studied medicine at the best university in the country and successfully managed more than 10,000 patients during his career.” The patient’s quick System 1 answer to this question will likely be “yes,” but it will be based only on partial information. If it was revealed that Dr. Brown’s extensive experience was limited to oncology, the patient’s answer might have been different. However, the heuristics inherent to System 1 thinking led to the patient’s prompt yet ill-informed decision.

Consider the question “Is Dr. Brown nice to his patients?”. The initial reaction to this question would differ if it was instead phrased as “Is Dr. Brown mean to his patients?”. Determining the most accurate answer to these questions would require a System 2 analysis of relevant information, which may be unavailable. Instead, System 1 tends to seek available information that would confirm the immediate belief. Kahneman identifies this heuristic as confirmation bias10, which can lead to exaggerated emotional coherence. This is known as the halo effect. For example, patients are likely to assess physicians’ clinical skills as a function of their interpersonal skills. This is because patients can assess good interpersonal skills but may know nothing about medical practice. The halo effect can also have a substantial impact on medication adherence; in fact, a poor relationship with one’s doctor is one of the major drivers of non-adherence. Therefore, patients who like their prescribing doctors are more likely to be adherent to medication than those who dislike their doctors12.

What Systems 1 and 2 can tell us about the behavior of menopausal women

Menopause is a unique period in a woman’s life, one that is difficult to prepare for. This is especially true when symptoms just begin to appear; the brain is not accustomed to them, and System 2 does not provide any insights to System 1 on how to process the changes. Furthermore, given the relative taboo surrounding the discussion of menopause, a woman may feel alienated by society (including friends, family, and colleagues) during the menopausal transition in which she may need support the most. When symptoms appear, System 1 may influence the decision to “hide” from society, which increases feelings of loneliness. Such decisions may lead to anxiety and depression, as well as contributing to non- adherence to the very medication that can help. As previous articles have indicated, training the systems that guide human decision-making processes may help break taboos related to menopause discussion. But how can this be achieved? The first step is to understand the underlying decision-making processes that human beings employ, as well as the heuristics that drive them.

Taking this decision-making process into account is a promising way to help people adapt behavior that leads to better health outcomes, including adherence to medication. Understanding the human decision- making process and the dominant heuristics that drive it has already proven its efficiency in many domains, such as economics, marketing, and many other fields. Today, this concept is building traction in healthcare studies, which will be evidenced in the next article.

Read more

Menopause’s impact on women’s lives and adherence to treatment during the peri- and post-menopausal period

Heuristics and decision-making: What are the effects on women going through the menopause


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