Do you know what a cognitive bias is? Do you know which ones can interfere in the teacher-learner relationship and have significant effects on learning? Do you have any idea of how a teacher can avoid them? Test your knowledge by answering the following five questions.

1. True or false? Cognitive biases are shortcuts of the mind that allow the brain to simplify the processing of information.



Cognitive biases are perceptual distortions that could be said to be to our mind what optical illusions are to our visual system. They lead us to make erroneous judgments or poor decisions on a daily basis. They are unavoidable, but we can learn to detect them better, starting with a better understanding.

To date, there are about 250 of them, some of which are more likely to interfere with the teacher-learner relationship and have significant effects on learning.

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2. The “Pygmalion effect” was brought to light in the 1960s by psychologist Robert Rosenthal and school principal Lenore Jacobson. It is one of the cognitive biases that should be taken seriously in education. Its name refers to the Greek mythological legend in which the king-sculptor Pygmalion fell in love with Galatea, his creation, a living statue. Which of the following statements about this cognitive bias is incorrect?

A) This effect occurs when the simple act of showing someone that you believe in their chances of success influences their performance, especially if you are in a position of authority or influence in relation to that person.

B) In social psychology, it corresponds to the phenomenon of “self-fulfilling prophecy,” which occurs when an erroneous belief leads to its own realization.

C) One key mechanism for realizing the Pygmalion effect is the learner’s internalization of the teacher’s perception of his or her ability to succeed.

D) One way of counteracting its negative effects on education is to encourage teachers to have low expectations of their students.



The opposite of the Pygmalion effect is sometimes referred to as the Golem effect. This occurs when a person in a position of authority judges an individual’s ability to succeed to be limited, and the latter performs less as a result. In social psychology, the Pygmalion effect and the Golem effect correspond to the phenomenon of “self-fulfilling prophecy,” which occurs when an erroneous belief leads to its own realization.

Countering the Pygmalion effect – or the Golem effect, for those who call it that – in the teacher-learner relationship is no simple matter (see Cognitive biases in education: the Pygmalion effect). According to developmental psychologist and neuroscientist Olivier Houdé, the way to overcome this is to develop “cognitive resistance”, or “learning to think against oneself” (see The 3 speeds of thought). Trouilloud and Sarrazin, for their part, suggest “encouraging teachers to have high expectations of their students,” citing the study by Madon and colleagues, who observed that the positive impact of high expectations seems to outweigh the negative impact of low expectations on the part of teachers towards their learners. According to their synthesis, Trouilloud and Sarrazin note that high expectations play a part in optimizing learner success in four ways, since teachers are more inclined to:

  1. Create a warmer emotional climate.
  2. Provide more information on performance.
  3. Give more content and more difficult content to learn.
  4. Give learners more opportunities to answer and ask questions.

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3. Another cognitive bias to watch out for in the classroom is the “bias blind spot.” Its name evokes the visual bias we all have: an area of our retina is devoid of photoreceptors and, therefore, blind, so it’s our brain that completes the missing visual portion. Complete the following statement to make it correct:

In an educational context, the bias blind spot may cause a teacher to…

A) considers only those student interventions within their immediate field of vision.

B) has a polarizing influence on student debates.

C) behaves in a way that supports certain preconceived ideas about learners that they know to be wrong but would not apply to themselves.

D) None of the above.



The bias blind spot consists in noticing the impact of cognitive biases much better in others’ judgments than in one’s own. In reality, we’re all just as susceptible to being fooled by cognitive biases…

One of the phenomena at the root of this bias is the high value we generally place on information derived from introspection (Pronin and Kugler, 2007). As a result, when we evaluate our own perceptions, we tend to give more credence to information that comes from our thoughts than from our actions, whereas we do the opposite when we judge others, giving more importance to their actions than to their thoughts, even if we are aware of the latter.

In an educational context, the bias blind spot can mean that a teacher adopts a behaviour towards learners that is in line with certain preconceived ideas that they know to be wrong and which they would not apply to themself. Think, for example, of the stereotype that males are better at certain types of learning (math, science, sports, etc.) and females at others (reading, writing, humanities, etc.); or the stereotype that people of certain origins are “naturally” better at certain subjects, e.g. Asians in math and science.

Find out more: 3 cognitive biases to be aware of in education

4. The “halo effect” occurs when we create a general impression of a person based on a single perceived characteristic. This cognitive bias affects not only our perception of others but also our expectations of them. What solution(s) do teachers have to reduce the risk of the halo effect influencing their interactions with their students or biasing their assessments of their performance?

A) Favoring blind corrections by asking learners to identify their work and exams by student number rather than name.

B) Give priority to oral presentations in front of the class.

C) Ask for work to be presented in a personalized manner.

D) Ask that work be presented in a uniform manner unless the presentation is subject to evaluation.


A. and D.

These solutions can reduce the risk of the teacher falling victim to the halo effect, and thus promote equal opportunities for learners to succeed. Marking assignments and exams obviously involves judging learners’ performance (Durand and Chouinard, 2012), and any judgment is unfortunately susceptible to bias (see The 3 speeds of thought).

Also known as the “notoriety effect” and the “contamination effect,” the halo effect manifests itself as described above when we build up a general impression of a person based on a single characteristic we perceive in them. If we judge this characteristic to be positive, we’ll tend to perceive or imagine their other characteristics to be positive, too; and conversely, if we evaluate this characteristic as negative, we’ll be more inclined to imagine or perceive their other characteristics to be negative, too.

A classic example of this halo effect is beauty. An American study carried out in the 1970s with primary school teachers produced telling results (Clifford and Walster, 1973). The teachers were presented with photos of children and asked to comment on three aspects: their intelligence, their chances of success and the extent of their parents’ involvement in their school activities. The result was that a child judged “beautiful” by the teachers was presumed to be more intelligent, more likely to succeed in class and to have parents more involved in their school activities than a child judged less beautiful.

Find out more: 3 cognitive biases to be aware of in education

The “curse of knowledge” is not a very easy cognitive bias to understand or recognize—at least, not in oneself! This bias manifests itself in the difficulty of putting yourself in the shoes of someone who doesn’t have that knowledge once you’ve acquired specific knowledge. Which of the following factors can further weaken the teacher’s vigilance against this bias?

A) The fact that the students are younger.

B) The fact that the students are older.

C) The fact that the students have a higher level of education or are studying in a highly specialized field.

D) The fact that the students have a low level of education and are studying the basics of a school subject.


B. and C.

Even if teachers are trained to develop their information dissemination skills, the act of teaching inevitably multiplies the risks of falling into the trap of the curse of knowledge.

Certain factors can further weaken the teacher’s vigilance against this bias; for example, the fact that students are older, have a higher level of education or are studying in a highly specialized field can encourage the teacher to make less of an effort to make their teachings understandable by everyone than would actually be desirable. In such a context, some learners may feel that they don’t have what it takes to understand the subject or even to make a career in this field, which might have interested them. Given the unfortunate effects this cognitive bias can have on learners’ careers, all teachers need to be aware that, despite their training as information conveyors, they too can fall prey to this curse of knowledge… Knowledge is the first step in warding off the curse!

Find out more: 3 cognitive biases to be aware of in education

Catherine Meilleur

Catherine Meilleur

Creative Content Writer @KnowledgeOne. Questioner of questions. Hyperflexible stubborn. Contemplative yogi.

Catherine Meilleur has over 15 years of experience in research and writing. Having worked as a journalist and educational designer, she is interested in everything related to learning: from educational psychology to neuroscience, and the latest innovations that can serve learners, such as virtual and augmented reality. She is also passionate about issues related to the future of education at a time when a real revolution is taking place, propelled by digital technology and artificial intelligence.