Understanding Unconscious Bias: Stereotypes, Prejudice and Discrimination

Understanding Unconscious Bias: Stereotypes, Prejudice and Discrimination

by Felicity Menzies

Stereotypes refer to beliefs that certain attributes, characteristics, and behaviours are typical of members of a particular group of people. The way we categorise social groups is often based on visible features that provide the largest between-group differentiation and least within-group variation (for example, skin colour, gender, age). We construct stereotypes from direct personal experience or, more commonly, from other people, or via the media. The media has a large influence on stereotype formation when we have limited opportunities for meaningful exchange with people from outside our own social group.

The benefits of stereotypes

The human brain has a natural tendency to categorise everything. At any one time, our brain is bombarded with an infinite number of stimuli. Without an efficient method of making sense of this information, our brains would become overloaded. By sorting stimuli (for example, experiences, objects, people) into categories, we can process our environments more efficiently. This frees up mental resources for other tasks.

Categorising people helps us to navigate our social world more efficiently. Social categorisation provides a sense of order and predictability that we can rely on to guide our interactions with others. Our stereotype for the elderly alerts us to speak loudly in their company. When we are ill, our stereotype for doctors leads us to seek out and trust their advice.

Differences in the tendency to stereotype

Researchers have demonstrated that individuals with a greater need for control are more likely to use stereotypes.

In addition, when we have limited mental resources available for making sense of our social environment, we rely more on stereotypes to make judgements and guide our behaviours. Reliance on stereotypes is more pronounced when we are distracted by another mentally taxing task, or when we are under emotional or physiological stress.

The problems with stereotypes


Some stereotypes are informed generalisations about a group of people. It is generally true, for example, that younger people have better hearing than older people. Yet many of our stereotypes are invalid— particularly when they are based on race, religion, or gender. Because of this, stereotypes can be problematic and counter-productive when working with diverse others.


Stereotypes are arbitrary ways of categorising individuals. No social group is homogenous. Stereotypes might not accurately represent the characteristics of a particular member of that group.


Research shows we that believe individuals from the same social group to be more similar than they really are. We also tend to exaggerate the differences between social groups. An American is likely to believe that all German people are very similar across a broad range of characteristics, and that Germans are very different from Italians.

Researchers also report bias in our categorisations of out-groups and in-groups. Out-groups are social groups to which we do not perceive ourselves as belonging. In-groups are the social groups with which we most identify. We perceive members of out-group members as sharing similar characteristics, but we think of in-group members as having unique characteristics and attributes.

Prejudice & discrimination

As well as shaping our beliefs about people, stereotypes drive social judgements. Prejudice refers to our feelings or attitudes about a group and its members. Prejudice is commonly associated with stereotypes; our evaluations of others reflect what we believe to be true about them.

Discrimination refers to differential (usually unfair or negative) treatment of individuals perceived to be belonging to a particular social group; for example, being overlooked in promotion or hiring, or being treated with hostility.

Discrimination is linked to stereotypes and prejudice. Strong egalitarian social norms, however, might deter a prejudiced person from acting in a discriminatory manner.

Bias in the workplace

Stereotypes, prejudice, and discrimination create physical and emotional distance between members of different social groups. Mild forms of bias can lead to awkward and uncomfortable interactions, intentional or unconscious avoidance, and interactions lacking warmth or civility. More extreme forms of bias can lead to tension and conflict, hostility, harassment, or aggression.

Stereotypes and other forms of bias can overshadow the strategic benefits of diversity by preventing all employees from contributing to work processes. 

Companies that do not address internal bias might also face costly discrimination claims.

Unconscious bias

Researchers have shown that stereotyping and associated responses are automatic and unconscious. A particularly disturbing example involves a series of experiments in which participants played a video game. During the game, an individual who was sometimes White and sometimes Black appeared spontaneously, carrying either a gun or a different, non-threatening object. The participants were told to ‘shoot’ when the intruder was carrying a gun, but to press another key if the intruder was carrying a benign object. The results showed that the number of times the participants accidentally perceived the object to be a gun was much higher for the Black intruder than for the White intruder. The results were similar for White and Black participants, indicating that negative stereotypes can exist intragroup as well as intergroup.

Stereotype resistance

Stereotypes are maintained and reinforced by powerful mental biases that filter out information that contradicts or challenges preexisting beliefs or attitudes.

Attribution bias

Stereotypes are maintained by biases in the attributions we make about a person’s behaviour. When a person behaves in accordance with a stereotype, we attribute that behaviour to the stereotypical characteristic they share with other members of their group. This reinforces the stereotype. However, if an individual behaves in contrast to a group stereotype, we are more likely to attribute that behaviour to external causes, preserving the integrity of the stereotype.

Attention bias

Similarly, research shows we pay more attention to action that is consistent with a stereotype than to action that contradicts a stereotype.


When a member of a stereotyped group displays counter-stereotypical qualities, this might also evoke subtyping. Subtyping involves explaining an exception by assigning that individual to a subcategory of the stereotyped group rather than modifying the original stereotype.

Self-fulfilling prophecy

Stereotyped individuals might act in a manner consistent with the stereotype as they react to out-group members. For example, if an outsider believes that a social group is aggressive, this might cause him or her to act antagonistically or with animosity towards members of that group. Stereotyped group members might then respond with to the outsider with hostility. This unintentionally reaffirms and reinforces the stereotype.

Allen, V. L., & Wilder, D. A. (1979). Group Categorization and Attribution of Belief Similarity. Small Group Behavior, 10(1), 73-80.
Allport, G. W. (1979). The Nature of Prejudice. New York, NJ: Addison Wesley.
Bargh, J. A., & Williams, E. L. (2006). The automaticity of social life. Current directions in psychological science, 15(1), 1-4.
Bargh, J. A., Chen, M., & Burrows, L. (1996). Automaticity of social behavior: Direct effects of trait construct and stereotype activation on action. Journal of personality and social psychology, 71(2), 230-244.
Bodenhausen, G. V. (1990). Stereotypes as judgmental heuristics: Evidence of circadian variations in discrimination. Psychological Science, 1(5), 319-322.
Brewer, M. B. (1988). A dual process model of impression formation. In R. Wyer, S. Jnr & T. K. Srull (Eds.), Advances in social cognition (Vol. 1, pp. 1-36). Hillsdale, NJ: Erlbaum.
Correll, J., Park, B., Judd, C. M., & Wittenbrink, B. (2002). The police officer’s dilemma: Using ethnicity to disambiguate potentially threatening individuals. Journal of personality and social psychology, 83(6), 1314-1329.
Correll, J., Urland, G. R., & Ito, T. A. (2006). Event-related potentials and the decision to shoot: The role of threat perception and cognitive control. Journal of Experimental Social Psychology, 42(1), 120-128
Cummings, A., Zhou, J., & Oldham, G. R. (1993). Demographic differences and employee work outcomes: Effects on multiple comparison groups. Paper presented at the Annual Meeting of the Academy of Management, Atlanta, GA.
Dijksterhuis, A., & Van Knippenberg, A. (1998). The relation between perception and behavior, or how to win a game of trivial pursuit. Journal of personality and social psychology, 74(4), 865-877.
Duncan, B. L. (1976). Differential social perception and attribution of intergroup violence: Testing the lower limits of stereotyping of Blacks. Journal of personality and social psychology, 34(4), 590-598.
Hilton, J. L., & Von Hippel, W. (1996). Stereotypes. Annual review of psychology, 47(1), 237-271.
Kim, H.-S., & Baron, R. S. (1988). Exercise and the illusory correlation: Does arousal heighten stereotypic processing? Journal of Experimental Social Psychology, 24(4), 366-380.
Merton, R. K. (1948). The self-fulfilling prophecy. The Antioch Review, 8(2), 193-210.
Park, B., Wolsko, C., & Judd, C. M. (2001). Measurement of subtyping in stereotype change. Journal of Experimental Social Psychology, 37(4), 325-332.
Shelton, J. N., & Richeson, J. A. (2005). Intergroup contact and pluralistic ignorance. Journal of personality and social psychology, 88(1), 91-107.
Von Hippel, W., Sekaquaptewa, D., & Vargas, P. (1994). On the role of encoding processes in stereotype maintenance. In M. P. Zanna (Ed.), Advances in experimental social psychology (Vol. 27, pp. 177-254). San Diego, CA: Academic Press.
Fiske, S. T. (1998). Stereotyping, prejudice, and discrimination. In D. T. Gilbert, S. T. Fiske, & G. Lindzey (Eds.), The handbook of social psychology (Vol. 2, pp. 357-411). Boston: McGraw-Hill.
Fiske, S. T. (2002). What we know now about bias and intergroup conflict, the problem of the century. Current directions in psychological science, 11(4), 123-128.
Fiske, S. T., Neuberg, S. L., Beattie, A. E., & Milberg, S. J. (1987). Category-based and attribute-based reactions to others: Some informational conditions of stereotyping and individuating processes. Journal of Experimental Social Psychology, 23(5), 399-427.
Ford, T. E., & Stangor, C. (1992). The role of diagnosticity in stereotype formation: Perceiving group means and variances. Journal of personality and social psychology, 63(3), 356-367.
Hewstone, M. (1990). The ‘ultimate attribution error’? A review of the literature on intergroup causal attribution. European journal of social psychology, 20(4), 311-335.
Hilton, J. L., & Von Hippel, W. (1996). Stereotypes. Annual review of psychology, 47(1), 237-271.
Lippmann, W. (1922). Public Opinion. New York: Macmillan.
Linville, P. W. (1982). The complexity–extremity effect and age-based stereotyping. Journal of personality and social psychology, 42(2), 193-211.
Macrae, C. N., & Bodenhausen, G. V. (2000). Social cognition: Thinking categorically about others. Annual review of psychology, 51(1), 93-120.
Macrae, C. N., Hewstone, M., & Griffiths, R. J. (1993). Processing load and memory for stereotype‐based information. European journal of social psychology, 23(1), 77-87.
Macrae, C. N., Milne, A. B., & Bodenhausen, G. V. (1994). Stereotypes as energy-saving devices: A peek inside the cognitive toolbox. Journal of personality and social psychology, 66(1), 37-47.
Nelson, L. J., & Miller, D. T. (1995). The distinctiveness effect in social categorization: You are what makes you unusual. Psychological Science, 6(4), 246-249.
Ostrom, T. M., & Sedikides, C. (1992). Out-group homogeneity effects in natural and minimal groups. Psychological Bulletin, 112(3), 536-552.
Park, B., & Judd, C. M. (1990). Measures and models of perceived group variability. Journal of personality and social psychology, 59(2), 173-191.
Pelled, L. H. (1996). Demographic diversity, conflict, and work-group outcomes: An intervening process theory. Organization science, 7(6), 615-631.
Sagar, H. A., & Schofield, J. W. (1980). Racial and behavioral cues in Black and White children’s perceptions of ambiguously aggressive acts. Journal of personality and social psychology, 39(4), 590-598.
Stangor, C., Lynch, L., Duan, C., & Glas, B. (1992). Categorization of individuals on the basis of multiple social features. Journal of personality and social psychology, 62(2), 207-218.
Stone, J., Perry, W., & Darley, J. M. (1997). “White men can’t jump”: Evidence for the perceptual confirmation of racial stereotypes following a basketball game. Basic and Applied Social Psychology, 19(3), 291-306.
Tajfel, H., & Wilkes, A. L. (1963). Classification and quantitative judgement. British Journal of Psychology, 54(2), 101-114. doi
Wigboldus, D. H., Sherman, J. W., Franzese, H. L., & Knippenberg, A. v. (2004). Capacity and comprehension: Spontaneous stereotyping under cognitive load. Social Cognition, 22(3), 292-309.
Wilder, D. A. (1984). Empirical contributions: Predictions of belief homogeneity and similarity following social categorization. British Journal of Social Psychology, 23(4), 323-333.


Felicity Menzies is CEO and Principal Consultant at Include-Empower.Com, a diversity and inclusion consultancy with expertise in inclusive leadership, unconscious bias, cultural intelligence and inclusion, gender equity, empowering diverse talent. Felicity is an accredited facilitator with the Cultural Intelligence Centre and the author of A World of Difference. Felicity has over 15 years of experience working with and managing diverse workforces in blue chip companies and is a Fellow of Chartered Accountants of Australia and New Zealand. Felicity also holds a Bachelor of Commerce and a Bachelor of Arts in Psychology.