Cognitive Biases, List of

Cognitive biases are systematic patterns of deviation from norm or rationality, and are studied in fields ranging from psychology to behavioral economics.

Cognitive biases can be organized into four categories:

Biases that arise from…

  • too much information,
  • not enough meaning,
  • the need to act quickly, and
  • the limits of memory.

Although the reality of these biases is confirmed by replicable research, there are often controversies about how to classify biases or how to explain them. Some are effects of information-processing rules (i.e., mental shortcuts), called heuristics, that the brain uses to produce decisions or judgments. Such effects are called cognitive biases. Biases have a variety of forms and appear as cognitive bias, such as mental noise, or motivational bias, like when beliefs are distorted by wishful thinking. Both effects can be present at the same time.

There are also controversies about whether or not some of these biases count as useless or irrational, or whether they result in useful attitudes or behaviors. For example, when getting to know others, people tend to ask leading questions which seem biased towards confirming their assumptions about the person. However, this kind of confirmation bias has also been argued to be an example of social skill: a way to establish a connection with another person.

Although this research overwhelmingly involves human subjects, some findings that demonstrate bias have been found in non-human animals as well.


The different types of biases include: