Our minds are unable to process big chunks of information consciously. Most of the data we perceive is processed subconsciously.

The mind, however, needs to establish some filters and automatizations in order to save energy it would otherwise spend to analyze all the information.

Mental Biases When There is Too Much Information to Be Processed:

Mental Bias: Availability Heuristic

Availability Heuristic is a mental shortcut that helps you make a decision based on the information you have about a certain subject overestimating the knowledge you already have. The things you are seeing constantly you think are reality for everyone everywhere.

The things people see on the news think are what’s happening in the world while they are just a tiny, but most captivating information the news companies filtered out to grab their viewers attention.

Mental Bias: Attentional Bias

Attentional Bias is the tendency for people’s perception to be affected by their recurring thoughts at the time. The type of thoughts you have will paint the reality you see in a certain place.

If two people go on a beautiful beach, but one of them just watched a scary shark movie, this person will have much different perception and experience of the beach than the person who didn’t watch the movie.

Mental Bias: Illusory Truth Effect

Illusory Truth Effect is the tendency to accept a statement as true the simpler it is for your brain to process it and the more times you heart it being stated.

If two politicians state they will fix the education system in their country, one says it simply and many times, but vaguely, and the other explains it complexly and once, but throughly, people will believe it the one who says it simply, many times even though it’s vaguely.

Mental Bias: Mere Exposure Effect

Mere Exposure Effect is a psychological phenomenon whereby people feel a preference and trustworthiness for people or things simply because they are familiar.

If you enter a supermarket wanting to buy a drink, and there are countless drink products you can choose from, you will decide to buy a product you were previously exposed to. Maybe someone you know drank it or you’ve watched an ad or commercial, but you’ll choose it merely because you have previously seen it and find it familiar. It doesn’t mean it’s better than the rest of the products. So, instead of researching all products to learn how they are made, it’s easier to filter and choose based on familiarity.

Mental Bias: Context Effect

Context Effect is a psychological phenomena where a change of context can affect the way we perceive reality. The way the context changes can change the way we construct reality even though nothing has changed.

If you see someone taking food from a homeless person while they sleep, you’ll see them as evil. However, if it turns out the context behind the situation was that the person taking the food knew the food was poisoned, so he tries to take it before the homeless man wakes up and eats it, you will see it as a Nobel act of heroism and kindness. The whole reality of the perceived situation has changed only because the context changed.

Mental Bias: Cue Dependent Forgetting

Cue Dependent Forgetting is a mental tendency of linking memory with certain cues and objects, and your mind fails to recall those memories without those certain cues.

If someone tries and fails to recollect the memories he had about a vacation he went on, and someone mentions the fact that he hired a classic car during this vacation, this may make him remember all sorts of things from that trip, such as what he ate there, where he went and what books he read.

Mental Bias: Mood Congruent Memory Bias

Mood Congruent Memory Bias is the tendency to recall memories that are congruent with your current mood. It’s the phenomena to be interested in things that are congruent with your current mood.

If you are in a happy mood you will recall memories that made you happy. If you are in a sad mood you will recall sad memories. If you are in a sad mood you will have the tendency to want to listen to sad songs that are congruent with your sad mood whilst, if you are in a happy mood you will have the tendency to want to listen uplifting and happy music.

Mental Bias: Frequency Illusion

Frequency Illusion is a phenomena that happens after we learn a new information and we start seeing and noticing it everywhere. It’s because our reticular activation system is primed to notice it after we learn it.

If you learn a new word and what it means you will start hearing it everywhere. It’s because after you learn it it’s in your awareness and you are primed to notice it. Other times when it wasn’t in your awareness you just ignored it.

Mental Bias: Empathy Gap

Empathy Gap is a mental fallacy to understand the reality of a certain individual if they do not share the same emotional state. Empathy toward someone might make you judge the reality of their situation falsely.

If you see a person being angry and throwing tantrums you will see their behavior as unreasonable and childish. But if you are really angry you will not realize how others perceive your behavior thinking your momentary goals driven by the anger are your long term goals. If you judge a criminal you don’t know it will be much easier to give a verdict than if the person being judged is a relative of yours you have empathy for.

Mental Bias: Omission Bias

Omission Bias is a mental fallacy to judge harmful actions much worse than inactions that are equally harmful just because the actions and their outcomes are more seeable.

If you and someone you need to compete with enter a restaurant before the game. The person is allergic to a certain ingredient in a food in the menu and you know it. Ordering that food for them will be judged much worse than stoping them from ordering it themselves. If you order this food for them it will be considered as much worse action than doing nothing if they order this food for themselves. The result is equally harmful.

Mental Bias: Base Rate Fallacy

Base Rate Fallacy is a mental fallacy to come to a conclusion based on some exact information that has almost nothing to do with the result ignoring the base information.

If there is a city with 100 million people population and only 100 of these people are criminals it’s not smart to insert criminal recognition cameras if they have 1% failure rate. This, even though counter intuitive, is a correct statement because even though the cameras might catch 99 criminals they will also catch 999,999 innocent people. The tendency to overlook this fact is the nature of this fallacy. It’s used in marketing to highlight information that means nothing in reality with a tendency to make a product more attractive. There might be something like “This product gives you 100% Vitamin C” and it means nothing. It doesn’t say how much of the vitamin there is in the product nor explains 100% of what. And of course if there is any Vitamin C inside you’ll get 100% of it if you consume the product. However, showing this on the product creates an illusion that it’s healthy without any lies.

Mental Bias: Bizarreness Effect

Bizarreness Effect is the tendency of your mind to better remember some bizarre material than common material. The strangest something appears the bigger the chance is for us to remember it.

If you need to remember your grocery list of Milk, Gums, Broccoli, and Onions, it’s much more effective if you use the first letters of the groceries MGBO to create a bizarre sentence than a normal one. You will remember more something like “My Green Baboon Ollie” than “My Good Baby Ollie”.

Mental Bias: Humor Effect

Humor Effect is a psychological phenomenon that causes people to remember information better when that information is perceived as funny or humorous.

If you were given a rough chunk of information on a list you can read in one minute, and you are given a 5 minute video of funny animation that explains the same information, you will remember much better and much faster the information from the funny animation video even though it’s longer just because it’s humorous.

Mental Bias: Von Restorff Effect

Von Restorff Effect is a mental tendency to remember the thing that differs the most. It predicts that when multiple homogeneous stimuli are presented, the stimulus that differs the most will be most remembered.

If you are given 6 balls where 5 red balls and 1 green ball, you will remember the green ball better just because it differs from the red balls.

Mental Bias: Picture Superiority Effect

Picture Superiority Effect is the mental tendency to remember pictures with information 6 times better than just words. The human memory is extremely sensitive to symbolic modality of information.

If you attend a presentation of 10 minutes without a slideshow of images you will remember 10% of the presentation after 3 days. If you attend a presentation of 20 minutes with slideshow of images that explain the information in a symbolic manner you will remember 65% of the presentation after 3 days.

Mental Bias: Self Relevance Effect

Self Relevance Effect is the mental tendency to better remember information that is implied as somehow personally related to them than the same information if implied as unrelated to the person.

If a person who is fat is presented a hygiene product by two commercials with two different people, one person who is also fat, and the other person who is fit and exercises during promoting the same product, the person will remember and be more influenced by the commercial with the fat presenter.

Mental Bias: Negativity Bias

Negativity Bias is a mental tendency to remember negative things over positive things even though the outcome of both events might be the same or have a neutral result.

If you walk on a street and find 20$ bill as you go to work, and this happens 3 times in one month, but at the same month you lose 50$ somewhere, you will remember losing 50$ much more than finding 60$ in total, even though you did not lose any of your own money, and you were lucky enough to find 60$ the same month, 10$ being still in the positive.

Mental Bias: Distinction Bias

Distinction Bias is the tendency to view two options as more distinctive when evaluating them simultaneously than when evaluating them separately.

If you know two identical twins you probably think they are the same. You cannot distinguish one from the other. But if they both come and you compare them simultaneously you will notice many things they are different in.

Mental Bias: Anchoring Bias

Anchoring Bias is a cognitive bias for an individual to rely too heavily on an initial piece of information offered when making decisions, especially the first one. The trust of this information decides the intensity of their reliance.

If you were told that someone is a bad person before you meet them and you were given an information about something slightly bad they did, let’s say they shoplifted something, you will assume they are a bad person even though that might be the only bad thing they have ever did. You will look at them and filter their behavior through a prism of a bad person. However, if someone told you an information of something good this person did first, let’s say they helped an old lady cross the street, you will not take the shoplifting so seriously. They will be a good person for you despite it.

Mental Bias: Conservatism Bias

Conservatism Bias is a bias in human information processing, which refers to the tendency to revise one’s belief insufficiently when presented with new evidence. People emphasize pre existing information over new data.

If you believe in something, let’s say that exercising every day is healthy, and a new scientific research proved this not just to be wrong, but even unhealthy, you will not accept this new information immediately even though the belief you have is based on word of mouth information that stuck with you, and the research is based on real life results gathered through the scientific process of testing and evaluating real evidence.

Mental Bias: Contrast Effect

Contrast Effect is the enhancement or diminishment of perception, cognition or related performance as a result of exposure to a stimulus of lesser or greater value in the same dimension.

If you want to buy a pair of pants and the price on one of them says 100$ you will think twice about it and maybe not even buy them. But if the price says discount from 240$ to 120$ on the same pair of pants, it is more likely that you will buy them, even though 120$ is a higher price than 100$ just because you have a contrast of these pants being more expensive.

Mental Bias: Framing Effect

Framing Effect is the tendency for people to react to a particular choice in different ways depending on how it is presented. They tend to avoid risk when a positive frame is presented but seek risks with a negative frame.

If something bad happens at the start of your day, let’s say you hit your leg from the table, and you think to yourself the day started bad, you will look for negative things throughout your day. If later that day someone shows you a good opportunity you will look for risks, ignore it or think of it in a negative light. But if your day started with something positive happening to you, let’s say the person you like sent you a message, and you think to yourself that it is a good day, you will look at the same opportunity later that day in a much more positive light.

Mental Bias: Money Illusion

Money Illusion is the tendency of people to think of currency in nominal, rather than real, terms. People tend to look at the amount of money before the purchasing power.

If you have a choice to make 10K$ per month in a developing country or 20K$ per month in a first world country you will probably choose to make 20K$ per month in a first world country. However, the difference in cost of lifestyle, bills and other expenses in a first world country is almost three times higher than the monthly cost in developing countries. So 10K$ in a developing country might turn out to have much bigger purchasing power than 20K$ in a first world country. However, the amount of money is more appealing than their actual purchasing power.

Mental Bias: Weber Fechner Law

Weber Fechner Law is the tendency of the human mind to not perceive change as it becomes more complex. It’s a progressive distortion between the actual change in a physical stimulus and the perceived change.

If you are blindfolded and hold a weight in your hands of 1kg and someone adds another 1kg on your hand, you will notice the change. If you hold a 100kg weight with your hands, and someone adds the same 1kg, you will not perceive the change.

Mental Bias: Focusing Effect

Focusing Effect is a cognitive bias that occurs when people place too much importance on one aspect of an event, causing an error in accurately predicting the utility of a future outcome.

If you worked at a company where you disagreed with your manager and this led to arguing with him and eventually getting fired, you will think that disagreeing with your manager can lead you to getting fired. So in the next job you will avoid disagreeing with your manager. However, in reality, this piece of information, disagreeing with your manager, has nothing to do with getting fired. In fact, in some companies managers encourage employees to disagree with them openly. The previous manager might have had other issues with you or they might have been professionally limited to get a feedback. They might have had a big ego. The information you focused on, disagreeing with your manager, was a false pattern you recognized in the chaos of not knowing what you did wrong. It gives you a sense of security in knowing how to control your future behavior but it’s not based on reality and it’s not tested in more than one scenario. It’s just a random information you consciously or subconsciously chose to focus on and look at reality through that imaginary filter.

Mental Bias: Congruence Bias

Congruence Bias occurs when people over rely on directly testing a given hypothesis as well as neglecting indirect testing. We stuck with one hypothesis not questioning its validity and the possibility of other ones.

If you were told that the left button of two buttons doesn’t open the door, and you were asked to test this hypothesis and find out what button really opens the door, you will click the left button. Let’s say the door doesn’t open. You will come to a conclusion that the right button opens the door, where in fact, neither of the buttons open the door. The same might happen with circling the same place you think you left your keys, not questioning if there is another place you might have left your keys at.

Mental Bias: Confirmation Bias

Confirmation Bias is the tendency to search for, interpret, favor, and recall information in a way that confirms one’s preexisting beliefs. The effect is stronger for emotionally charged issues or deeply entrenched beliefs.

If you hold a belief that wearing your favorite team’s jersey while they play will grow their chances to win, you will overvalue the times you wore that jersey and your favorite team won, while you will overlook the times you wore that jersey and your favorite team lost. Even though your team might have lost more times you wore that jersey than they won, you will selectively gather evidence that confirm your preexisting belief because it takes a lot of energy for your mind to uninstall or reframe a belief.

Mental Bias: Post Purchase Rationalization

Post Purchase Rationalization is a cognitive bias whereby someone who has purchased an expensive product or service overlooks any faults or defects in order to justify their purchase.

If you can’t decide between two games, but eventually you come to terms to buy one of them, and the other one turns out to have better reviews, you will rationalize the greatness of the game you have purchased. You will start giving sour grape arguments, some of them might be how it’s best you bought this game because it’s not as addictive as the other one. It’s easier for your mind to handle financial and emotional investment than dealing with remorse on top of those.

Mental Bias: Selective Perception

Selective Perception is the tendency not to notice or quickly forget stimuli that contradict our beliefs. People tend to perceive what they feel is right, completely ignoring opposing viewpoints.

If you watch a show on TV about healthy eating habits with someone who strongly beliefs that diets are wrong and eating meat is healthy. And let’s say the doctor on TV is explaining the benefits of not eating meat and the harmful effects of various diets. The person watching with you, who wants to eat meat, will not even perceive the things being said about the benefits of not eating meat, but they will be  strongly agreeing with everything being said against diets. In their mind, the show is about why you shouldn’t take diets. They might even say all diets are harmful because they watched a doctor on TV say so.

Mental Bias: Choice Supportive Bias

Choice Supportive Bias is the tendency to retroactively ascribe positive attributes to an option we’ve selected. We tend to amplify the advantages of the selected option and not notice the bigger benefits of the other one.

If you can’t choose between two clubs but eventually you choose one of them, and it turns out to be ok, but the other club was slightly better, you will exaggerate the fun you had at the club you’ve chosen even though the other one is slightly better. Your mind will see the option you’ve chosen as better to prevent yourself from feeling regret for a small difference in the quality of the option.

Mental Bias: Observer Expectancy Effect

Observer Expectancy Effect is a form of reactivity in which a researcher’s expectancy causes them to subconsciously influence the participants of an experiment.

If a teacher believes some children are smarter than the other in the class, they will subconsciously act differently towards them, no matter how objective they try to be. Let’s say they want to test if they are right, if the children they believe are smarter are really smarter. So the teacher will observe how the children perform for a month. However, the teacher’s sole behavior towards the two groups of children might influence the results. The teacher might behave differently toward the two groups in ways that lead them to perform better or worse than the others, such as giving those children they believe are smarter extra attention and praise.

Mental Bias: Experimenter’s Bias

Experimenter’s Bias is the phenomena to have errors in a research study due to the predisposed notions or beliefs of the experimenter. The experimenter’s beliefs influence the outcome of the experiment.

If a male scientist has a preexisting belief that males choose more the color blue rather than the color red just because that’s his choice, he might influence the construction of the experiment with this bias. He might subconsciously skew the selection of subjects, the administration of the experiment, the analysis of the data, or the conclusions drawn to fit his belief. That’s why the experiments should be created by someone unbiased, someone who doesn’t care neither for blue nor red color.

Mental Bias: Observer Effect

Observer Effect is the occurrence where simply observing a situation or phenomenon changes that phenomenon. This is often the result of instruments altering the state of what they measure in some manner.

If you try to observe quantum particles without having any effect on them, and you need light to be able to observe them, the sole photons you will need for observation will alter the states of the quantum particles, hence, your observation will have an effect on the quantum particles you are trying to observe and change the measured result.

Mental Bias: Expectation Bias

Expectation Bias is the tendency for experimenters to believe or disbelieve, publish or discard data that agree with their expectations for the outcome of an experiment.

If you make an experiment about rolling a dice believing that the outcome will be the dice rolls more times on one, you might not accept the randomness of the result, you might create additional experiments to prove you are right instead of publishing the data of the first experiment that hinted the dice has no pattern when it rolls.

Mental Bias: Ostrich Effect

Ostrich Effect is the tendency to ignore a dangerous or risky situation with intention that it will go away or not affect us. People keep a problem out from their mind instead of tackling the situation which threatens them.

If a child is sleeping alone and hears a scary sound it will hide under the blanket, even though if there is real danger the blanket doesn’t provide any safety. Similarly we behave with problems. Let’s say you have bills you need to pay but you don’t have enough money. Instead of tackling this problem and finding a solution you distract yourself by watching TV or sports. But not thinking about the problem, even though it gives a momentary relief, is not solving the problem. And you can use the same time and energy to find a solution instead of distracting yourself from the unease that comes by thinking about the problem.

Mental Bias: Subjective Validation

Subjective Validation is a cognitive bias by which a person will consider a statement or another piece of information to be correct if it has any personal meaning or significance for them.

If you have blonde hair and you feel good when you eat fruits and veggies and someone tells you it’s because people with blonde hair have natural predisposition to metabolize fruits and veggies, you will believe this to be true just because the information has personal significance for you. However, most people feel good when they eat healthy foods and their hair color has nothing to do with any of it.

Mental Bias: Continued Influence Effect

Continued Influence Effect is the tendency to keep believing an information that you consciously know has been proven to be false. It refers to the way that falsehoods persist in our thinking.

If you see a commercial about a juice brand and they portray it as a healthy addition to a healthy breakfast including bacon and potatoes, you will believe that a healthy breakfast includes bacon, potatoes and juice. However, let’s say researchers prove that this combination is not so healthy. No matter if you consciously know this, an image of healthy breakfast for you will still include the juice, the bacon and the potatoes.

Mental Bias: Semmelweis Reflex

Semmelweis Reflex is the tendency to reject new evidence or new knowledge because it contradicts established norms, beliefs and paradigms. People lean more to previous knowledge rather than evidence.

If you believe that eating meat is healthy for you and new research comes saying eating meat is harmful for your health, you will not accept it, at least not immediately. People will justify that you need a little meat here and there, they will justify their belief with examples of people who are healthy and who ate meat all their life, maybe even that the research is flawed. And even if more evidence arises that consuming meat is unhealthy, you will most likely create an aversion toward people who accept this new lifestyle, by calling them names and labeling them as something. This is all because you are defending your previously established belief, it’s not about the people who believe the new research, it’s not about you knowing some better information, it’s just because you find it hard to remove an old belief and seek ways to make justification easier.

Mental Bias: Bias Blind Spot

Bias Blind Spot is the tendency of recognizing the impact of biases on the judgment of others, while failing to see the impact of biases on oneself. We have a blindspot for our own cognitive flaws.

If you read about biases and you speak with someone, you will most likely notice their cognitive flaws, or at least you will think you do. Let’s say they find it hard to accept new information you tell them and you point out to them they just made a cognitive fallacy, one where the person rejects new evidence because it contradicts established beliefs. However, you are blind to the fact that you yourself might be under influence of a bias, one where you have a selective perception. Maybe the person is simply not trusting the information you are telling them because it’s not supported by any research and evidence, and you assume it’s their bias talking. Maybe if they have some concrete evidence to look at they will accept the new information. In this scenario you are blind to your own bias of preselective perception.

Mental Bias: Naive Cynicism

Naive Cynicism is the phenomena when people naively expect more egocentric bias in others than actually is the case. They assume someone has egocentric intentions and filter things through this belief.

If you think a person thinks bad of you, and this is not based on any real evidence, you will assume their decisions are against you. Let’s say you speak with them and they sincerely say they do not like your outfit, you will perceive this argument as a personal attack even if it’s the kindest and most friendly advice they are trying to give. You’ll assume they say this with intention to appear as better than you.

Mental Bias: Naive Realism

Naive Realism is the cognitive fallacy to think that the senses provide us with direct awareness of objects as they really are. People tend to overly rely on the sense of sight and touch, as well as the other senses.

If you observe the world around you it’s very likely that you think reality is the way you perceive it. However, your senses absorb just a tiny amount of information from the world around you. Your eyes perceive less than 1% of the electromagnetic spectrum, your ears can hear less than 1% of the acoustic spectrum. Animals perceive things from reality you can’t because they have evolved different senses. And even the information you perceive sometimes is skewed. Even more, the biggest chunk of data, more than 90% is outside of your awareness processed by your subconsciousness. And yet, people think the reality they perceive is all there is of reality while they see just a tiny glimpse of what there is. Even memories get distorted due to memory distortion and remembering filters, and do not depict the exact reality of the situations you remember.