Confirmation Bias Psychology: Existing Beliefs And Decision-Making

Confirmation bias describes the human tendency to selectively interpret information in ways that align with pre-existing beliefs, often leading to overlooking or dismissing contradictory information. This phenomenon can be challenging to overcome and may lead to division, poor judgment, and polarized viewpoints. In this article, we take a closer look at confirmation bias, why it might occur, and its possible consequences in everyday life and on mental health.

Confirmation bias: Definition

The American Psychological Association defines confirmation bias as “the tendency to gather evidence that confirms preexisting expectations, typically by emphasizing or pursuing supporting evidence while dismissing or failing to seek contradictory evidence.” This APA dictionary definition is used in psychological literature and research, but understanding what confirmation bias means in plain language can help us better grasp how it can impact daily life. 

Confirmation bias might be thought of as the inclination of the human mind to believe information supporting one’s existing beliefs while discounting opposing beliefs. It can lead us to stop seeking further information to verify whether what we think is correct, regardless of the evidence. Cognitive bias can lead to numerous challenges, including flawed decision-making, narrow-mindedness, overconfidence, and tension in professional and personal relationships.

How confirmation bias works

Starting with a first impression or favored hypothesis

Hypothesis testing is the process of making a claim about the world, gathering evidence, and deciding whether to accept or reject that claim. It is typically used in research, but individuals can also use this process to figure out how they see the world and to eliminate hypotheses that do not align with their beliefs. 

Confirmation bias may begin as soon as someone forms a first impression or settles on a specific hypothesis. Research has identified a few different types of thinking processes involved in hypothesis testing: information searches, evidence interpretation, and memory recall. Each of these may be affected by confirmation bias, as people tend to seek, interpret, and recall information that supports what they already believe. Research also shows that the more confident people are in their beliefs, the more biased their information seeking may become.

What happens when evidence is presented

Research suggests that once people test their hypotheses, they are more likely to be drawn to information that confirms their personal biases. In other words, they may not evaluate the evidence presented to them naturally but, instead, favor information that confirms their hypothesis, add more weight to positive instances that align with their view, and overlook things that don’t fit. There can be many reasons for this, one of which may be that confronting contradictory evidence can create mental conflict, which many people may seek to avoid.

Confirmation bias in research and data analysis

Scientific research is generally designed to be as objective as possible, but researchers are human and may be as susceptible to confirmation bias as everyone else. It can be important to keep this in mind when relying on any formal research.

How researchers can favor information unintentionally

When researchers begin to analyze data, their expectations may influence the patterns that they notice and those that they miss. Even how they frame a conceptual task or choose which information to highlight can lead to an unconscious bias in how they interpret results.

How to reduce bias in hypothesis testing

One way to reduce bias is in how studies are designed. For example, research that seeks to eliminate hypotheses that don’t hold up may be more reliable than research that tries to confirm a very specific hypothesis. An effective way to counter possible confirmation bias from individual researchers is to use meta-analysis, a process that analyzes data from various studies about the same subject, which tends to give more reliable results than looking at one study individually. 

Examples of confirmation bias in everyday life

There are many ways in which people display confirmation bias. We take a closer look at some examples below.

Everyday decision making

Confirmation bias can play a role in how we process and gather information in everyday life. For example, someone may search for information about a medical symptom they are having and convince themselves that they have a rare or dangerous health condition. Rather than seeking care from a doctor or waiting to see if the symptom resolves, they may continue to read only information that confirms their suspicion. 

Another example may be checking the weekend weather if you have plans to do something outdoors. On Monday, you may find several outlets calling for rain on the weekend and one that does not, then decide that the one that best suits your plans is the most reliable option, and write off the predictions of others.

Confirmation bias in relationships and conflict

Confirmation bias can be tied to first impressions, and in relationships, these impressions may become the lens through which partners see one another. For example, if one partner gets the impression that the other never listens or is acting defensively, they may begin to see every interaction through that lens, developing negative emotions that can impact the entire relationship. 

These perceptions can have even more significant effects during times of conflict. When people argue, they may naturally look for information that validates and supports their opinion. For example, they may assign more weight to interactions that make their partner seem like they are being irrational or dismissive. Self-esteem may play a role, too, as people who have a negative idea of themselves may absorb criticism and ignore praise, which can make it appear that their partner is being critical and unsupportive when that was not what was actually being expressed or was something said in the heat of the moment.

Confirmation bias in news and online reading habits

While there are seemingly endless news sources online, it can be difficult to find unbiased information. Many social media platforms and search engines use algorithms to give users further information about topics that they are already interested in. AI summaries and social media posts can make it so that some people may feel they don’t have to read entire articles to understand the facts about a situation, and message boards and comment sections may be full of people who confirm what readers may already believe. 

For example, two friends might hold different views about the best solution for climate change. One supports solar power and reads articles affirming one's belief about the need for more investment in solar power. The other believes more in the importance of wind power and gravitates toward online articles that prove his position. While they both read new stories about climate change, they interpret the news through the lens of their confirmation bias. This can make it difficult to see the strengths of opposing arguments. 

Confirmation bias vs related biases

In addition to confirmation bias, there are other types of cognitive biases that can impact how we search for, process, and apply information. Many of them can overlap, feed into each other, or show up in similar situations.

Confirmation bias vs cognitive dissonance

Cognitive dissonance occurs when someone experiences mental conflict from holding inconsistent beliefs. A common example of cognitive dissonance may be someone who knows that smoking is unhealthy but continues to smoke cigarettes anyway. To cope with the conflict between their behavior and their belief, they may make excuses, such as: 

• My grandfather smoked until he was 90 and never got cancer. 
• I’ll quit as soon as this stressful week is over.
• Stress can be harmful to your health, too, and I would be so stressed out if I quit.

On the other hand, confirmation bias in smoking can affect how the person filters information and how it applies to them. For example, they may refuse to believe the validity of research that shows that smoking can cause lung cancer or believe that they will remain unaffected, despite any evidence to the contrary.

Backfire effect and belief polarization

The backfire effect is the idea that exposure to information that disproves one’s opinions strengthens their beliefs. Some examples may include: 

• Supporters of a politician who are presented with evidence proving that the politician made a false claim may believe the claim more strongly.
• Someone who believes a conspiracy theory may see all proof to the contrary as evidence of a cover-up.
• Someone who believes in astrology may write off evidence from a skeptic by attributing their disbelief to the traits of their astrological sign. 

Though the backfire effect and confirmation bias are similar, a key difference between them may be in how much conflicting information gets in. In confirmation bias, information that does not support the belief is generally written off or ignored. In the backfire effect, the person takes in the information but uses it to strengthen their opinions.

Halo effect and implicit bias

The halo effect, a type of implicit bias, occurs when one’s overall impression of a person is impacted by a positive trait. For example, someone who is physically attractive may be assumed to be intelligent and kind, or a job applicant who is well dressed may be assumed to be qualified for a job.

The halo effect is different from confirmation bias, but the two can be linked. Some examples of this might include: 

• You are interviewing a candidate who is well-dressed and articulate, so you assume they are qualified for the job. Throughout the interview, they exhibit knowledge gaps that may make them a poor choice for the role, but these are overlooked in favor of your first impression. 

• A luxury brand releases a new product, so you assume that it is high quality. After using it for a month, the product falls apart, but it does not change your opinion of the brand, and you continue to buy their products.

• You go on a first date with someone who is attractive and funny. After several dates, you explain away their negative traits but use positive interactions to reinforce your first impression.

Help for overcoming confirmation bias

If you think that you may be discounting information that goes against your existing beliefs, it may help to speak with a psychologist or licensed therapist about confirmation bias. One form of therapy that may help is cognitive behavioral therapy (CBT). In CBT, people typically learn to challenge their inaccurate beliefs and think in new ways. Also, therapy helps individuals to build self-awareness. This allows them to recognize when they are looking for information that confirms their existing beliefs.

If you feel hesitant to see a psychologist or therapist in person, you might consider online therapy. CBT is a type of therapy you can engage in remotely, and numerous studies confirm that online CBT is as effective as seeing a counselor in person. Talking to a mental health professional can be beneficial if you're struggling to process information more effectively without any biases.

With online CBT at BetterHelp, you can connect with a licensed therapist via audio, video, or live chat at a time that works for you. You can also message your therapist at any time through in-app messaging, and they’ll respond as soon as they can. This may be helpful if you encounter instances of bias and want to write down your thoughts in between sessions. In online therapy, cognitive biases may influence how individuals interpret feedback and engage with therapeutic strategies. From a social psychology perspective, confirmation bias also plays a role in shaping interactions, perceptions, and group dynamics, which can impact therapy outcomes.