man and woman in iat
Go back to blog
What is an Implicit Association Test (IAT)?
8 Min.
We are all somewhat biased due to our past experiences and the upbringing and education we have been given. It remains more or less unconscious in our minds, defining our beliefs, influencing our attitudes, and shaping our behavior. It is the reason why we associate the color black with elegance and red with passion. However, it is also the reason why technology is still more associated with boys than girls, or why, in part, we still suffer from racism.

To overcome these biases we first need to identify those implicit associations. However, just asking someone openly about their inherent prejudices or automatic preferences won't give us very accurate information, as it can be altered by several mechanisms, such as the social desirability bias or other cognitive biases.

The Implicit Association Test (IAT) is one of the implicit techniques developed by scientists, designed to uncover those unconscious attitudes and beliefs. Below you will learn what is the implicit association test and how this 10-minute test can tell you things about you that you probably didn't realize. 

What is an Implicit Association Test (IAT) work?

The first Implicit Association Test (IAT) was developed in 1998 (Greenwald, A. G., McGhee, D. E., & Schwartz, J. L. K., 1998). Years before, in 1995, social psychologists Mahzarin Banaji and Anthony Greenwald, stated the idea that, if memories that are not available to awareness can affect our actions, associations can also influence our attitudes and behavior.  The IAT was developed in order to prevent access to consciousness and therefore, to bypass the social biases that happen when using explicit techniques (interviews, surveys, or focus groups) and that can influence responses. 

Implicit Association Test Definition:

An Implicit Association Test  (IAT) is a psychological test whose objective is to reveal unconscious attitudes, automatic preferences, and hidden biases by measuring the time that takes an individual to classify concepts into two categories.

If the participant reacts quickly in classifying one concept into one category, it is said the relationship between the concept and the category is familiar, frequent, or inherent in the mind of the individual. That is, the concept and the category are mentally associated. 

For example, if a participant reacts significantly faster when pairing the word Success with Skinny (Category A) than with Fat (category B), Success and Skinny are implicitly more associated, more interconnected in the participant's mind. Depending on how the experimental design was defined, we could infer that the participant may give too much importance to body image, or that is just another victim of certain advertisements we are all surrounded by. In any case, IAT tests are uncovering implicit associations of these concepts that may not be accessible to the conscious mind, or that may be too controversial or embarrassing to bring to light.

Implicit Association Tests are just one of the several implicit bias tests that measure unconscious attitudes and beliefs in the market. However, IATs, along with Priming Tests, are the most commonly used by both academics and businesses to assess those implicit attitudes. If you want to learn more information about IAT, Priming Tests, and other implicit bias tests, please, follow this link

woman taking an online iat

How does the IAT work?

The Implicit Association Test is grounded in how our brains process information, a phenomenon explained, in part, by a dual-process model (eg, Strack & Deutsch, 2004) which differentiates between a propositional and associative information processing system:

  1. The Slow Route: The propositional system, also known as System 2 (Kahneman, 2011), corresponds to explicit reasoning processes and operates consciously but slowly.
  2. The Fast Route: The associative system, also known as System 1  (Kahneman, 2011), corresponds to the spread of activation processes and operates quickly but with limited conscious accessibility (Schnabel et al., 2008).

So, what does the IAT measure? The IAT seeks to measure only the fast route so the responses contaminated by the conscious mind get suppressed and eliminated. One of the main questions is at which time intervals are responses triggered by system 1 and by system 2. 

Timing of System 1 and System 2

When a stimulus event takes place (0ms), our brain starts processing the information. It takes approximately 200-300ms to process and to react to it, for example, by pressing a keyboard key. Accordingly, the responses that occur in less time than 200-300ms are considered too fast and should be eliminated. Responses that take longer than 650-900 ms are considered contaminated by conscious decision making and are also rejected.

graphic of the timing for the implicit reactions

However, there is no exact scope of time where System 1 occurs, because some participants react quicker than others, and some images or words are more complex to process than others. Several algorithm methods are applied to clean the data. 

Within the established timing, if a concept is more quickly classified into a category A than into a category B, the concept and the category A are more unconsciously associated in the mind of the participant. The quicker the answer, the stronger the association. 

What does an IAT look like?

We have developed an Implicit Association Test so you can experience how the test works. You can access it by clicking in the blue pop up that appears in the bottom-left part of this page. If it doesn’t appear, please, refresh your browser. After completing the test, you will have access to your personal IAT scores, along with the average results of the test that have been taken so far. 


In the IAT, the participant has to classify, as quickly as possible, words or images that will pop up in the screen into their corresponding category or attribute group. There are two categories and two attribute groups. Categories are the two targets we want to compare.

table with the categories and attributes of an example of a IAT test

There are multiple trials in which attributes and categories must be paired. For example, our brand + good vs. competitor + bad; and vice versa: our brand + bad vs. competitor + good

Phase 1: Instructions

First, directions are given to explain how to pair words and/or images as quickly as possible. It also shows the words and images that will appear in four category groups: 

In this study, you will complete an Implicit Association Test (IAT) in which you will be asked to sort pictures and words into groups as fast as you can. This study should take about 10 minutes to complete. Next, you will use the 'E' and 'I' computer keys to categorize items into groups as quickly as you can. 
If you make a mistake, a red X will appear on the screen. These are the four groups and the items that belong to each:

  • Good: Stylish, Robust, Fast, Light, Enduring, Sophisticated
  • Bad: Broken, Dirty, Outdated, Slow, Gross, Heavy
  • Category 1: 6 images of Category 1 
  • Category 2:  6 images of Category 2

Phase 2: Familiarization

Second, respondents have to classify each word or image that appears in the center of the screen into their correct categories using the “E” and “I” computer keys. First, the group of categories (Category 1 and Category 2) and then the group of attributes (Good and Bad). The objective of the familiarization phase is that respondents understand what they have to do and become familiar with the procedure. The results obtained in this phase will not be considered in the report.

iat familiarization

Phase 3: Test

Lastly, this phase includes several trials in which attributes and categories are paired and mixed. That is, this time the elements that will randomly pop up on the center of the screen belong to both categories or groups of attributes, and the location (at the corners) of the different groups to pair these elements with will also alternate in order to avoid learning biases, as shown in the image below.

iat test

If attributes of the category Good are more associated with Category 1, the time to pair them will be shorter. Good and Category 1 would be naturally associated in the participant's mind.

What do the IAT results look like?

IAT test results usually look like the graph below. The two bars correspond to the two attributes (groups of concepts), and the graph indicates the response times for classifying attributes into one of the categories. The shorter bar indicates a quicker classification and therefore, a stronger association of this attribute with this category.

iat results

Bringing the IAT to the next level

Online IAT

Online IAT tests, along with Priming Tests, have become a scalable and cost-effective research tool that allows gathering unconscious data of hundreds of participants in record time and cost savings. 

The participants do not have to go to a laboratory or wear any physiological sensors. The only requirements are a connection to the internet, a computer, tablet, or smartphone, and approximately 10 minutes of focus in order to accomplish the task. 

For this reason, IAT tests are being increasingly employed by brands, market research organizations, and other real-world (end-application) research institutes and other types of neuromarketing companies, in order to have an extra layer of nonconscious information from their audiences and better predict their behavior.  This way, IAT predicts nonconscious attitudes that help these organizations to improve their brand positioning strategies, selection of brand representatives, packaging analysis, how brand preference changes when viewing an advertising piece, or any other marketing element... In essence, IAT studies show the degree of non-conscious preference of the elements to be evaluated.

Combining IAT with other implicit and explicit methods

By combining implicit methods with other techniques such as EEG, GSR, BVP, eye tracking, etc; or declarative procedures such as surveys, interviews or focus groups, it permits researchers can develop to have a comprehensive understanding of what's going on in the participant’s mind, and thus, better understand their behavior. Bitbrain Labs, include these Implicit Bias Tests, that are frequently combined with Bitbrain's EEGGSR, BVPECG, EMG, temperature and respiration sensors, Indoor Positioning Systems, or Tobii Pro eye trackers, and with declarative procedures. 

participant performing an online IAt throughout his mobile phone


The Implicit Association Test was highly employed by social psychology scientists in order to explore unconscious attitudes towards racial groups, gender, sexuality, age, and religion.  After 40 years, implicit measures are still used, not only to widen social research discoveries but also to polish and improve these techniques. In addition, commercial applications such as consumer behavior or political preference research are being addressed and employed in order to predict and identify an implicit preference toward a product, brand, celebrity, or politician. 
If you want to continue learning about Implicit Bias techniques, their applications, and to see some interesting scientific references on the topic, read the Introduction to Implicit Bias Tests: IAT and Priming implicit test entry.

Don't forget to take the test!

Remember that you can access it by clicking in the blue pop up that appears in the bottom-left part of this page.  If it doesn’t appear, please, refresh your browser.

Other sources

Researchers at Harvard University, University of Washington, University of Virginia, and Yale University are involved in the Project Implicit, in which they make available a several of IAT to gather data on the non-conscious bias about discriminatory behavior, stereotypes, prejudices in races and ethnicity, religion, gender, sexual orientation, etc. You can take a test on their website. Along with your personal IAT scores, they will mention possible interpretations that have a basis in research done by those universities.

About the author 

Cristina Ocejo, Marketing Communications Director at Bitbrain (LinkedInTwitter)

Cristina Ocejo holds a BSc from the University of Barcelona and an MSc in Neuromarketing by the Autonomous University of Barcelona. Cristina has 8+ years of experience working in the advertising and fashion industry worldwide. She has performed internships at Kantar Millward Brown and SetUp Media and joined Bitbrain in 2017. She is currently in charge of the Bitbrain branding, online and offline marketing, and communications of the company.

Bibliography & References

  • Baumeister R.F., Hutton D.G. (1987) Self-Presentation Theory: Self-Construction and Audience Pleasing. In: Mullen B., Goethals G.R. (eds) Theories of Group Behavior. Springer Series in Social Psychology. Springer, New York, NY.
  • Banakou D, Hanumanthu PD, Slater M (2016) Virtual Embodiment of White People in a Black Virtual Body Leads to a Sustained Reduction in Their Implicit Racial Bias. Front. Hum. Neurosci. 10:601. DOI: 10.3389/fnhum.2016.00601
  • COVER, C. N. Experimental studies on the role of verbal processes in concept formation and problem solving. Ann. N. Y. Acad. Sci., 1960, 91, 94-107. 
  • Cramer, P. (1966). Mediated priming of associative responses: The effect of time lapse and interpolated activity. Journal of Verbal Learning and Verbal Behavior, 5(2), 163–166. doi:10.1016/s0022-5371(66)80010-5 
  • Genschow O, Demanet J, Hersche L, Brass M (2017) An empirical comparison of different implicit measures to predict consumer choice. PLoS ONE 12(8): e0183937.
  • Green, A. R., et al. (2007) Implicit Bias among Physicians and its Prediction of ThrombolysisDecisions for Black and White Patients. Society of General Internal Medicine 2007;22:1231–1238. DOI: 10.1007/s11606-007-0258-5
  • Greenwald, A. G., Poehlman, T. A., Uhlmann, E. L., & Banaji, M. R. (2009). Understanding and using the Implicit Association Test: III. Meta-analysis of predictive validity. Journal of Personality and Social Psychology, 97(1), 17–41.
  • Greenwald, et al., (2002). A Unified Theory of Implicit Attitudes, Stereotypes, Self-Esteem, and Self-Concept. Psychological Review. Vol. 109, No. 1, 3–25
  • Greenwald, A.G., & Banaji, M.R. (1995). Implicit social cognition: Attitudes, self-esteem, and stereotypes. Psychological. Review, 102, 4–27.
  • Kahneman, D. (2011). Thinking, fast and slow. New York: Farrar, Straus and Giroux.
  • STORMS, L. H. Backward association: a situational effect. ]. exp. Psychol., 1958, 55, 390-395.
  • Strack, F., & Deutsch, R. (2004). Reflective and impulsive determinants of social behavior. Personality and Social Psychology. Review, 8, 220–247.
  • Everything you need to know about Implicit Reaction Time (IRTs). (2015, September 30). Retrieved March 27, 2020, from
  • Tam, T., Hewstone, M., Harwood, J., Voci, A., & Kenworthy, J. (2006). Intergroup Contact and Grandparent–Grandchild Communication: The Effects of Self-Disclosure on Implicit and Explicit Biases Against Older People. Group Processes & Intergroup Relations, 9(3), 413–429.

You might be interested in: