The Psychology of the Halo Effect

Physical attractiveness often shapes how we perceive traits like intelligence, success, and kindness. This common tendency is explained by a psychological bias known as the halo effect. 

The halo effect is a type of cognitive bias where a single positive trait, such as attractiveness, influences how we judge an individual’s other characteristics. This occurs unconsciously, serving as an automatic mental shortcut. Our brains process large amounts of information daily, hence they rely on shortcuts to make quick judgements, with physical attractiveness serving as one such shortcut, leading to the generalisation from one positive trait to form a broader judgement. 

Gulati et al. (2024) investigated the halo effect using artificial intelligence-based beauty filters. In this online study, participants rated facial images in two conditions: original and attractive after applying a filter. A 7-point Likert scale was provided for seven attributes: attractiveness, intelligence, trustworthiness, sociability, happiness, femininity and unusualness. Findings illustrated that the same individuals receive significantly higher ratings of attractiveness and other traits, like intelligence, in the attractive condition. This illustrates that people perceive attractive individuals as more sociable and trustworthy, even when there is no evidence of such traits, illustrating the halo effect in place. Similarly, findings from Lenoir & Stocks (2020) illustrated that attractive individuals are judged to behave more positively and to exhibit fewer negative behaviours. Together, these studies highlight how one characteristic can form general perceptions of personality. However, Gulati et al. (2024) also concluded that although faces with the filter received higher ratings, the strength of the link between attractiveness and trait judgements became weaker in the filter condition – attractiveness still influenced trait judgements, but had a weaker influence on participants’ judgments of personality traits. This may be because when people use beauty filters, attractiveness becomes artificial, and therefore, people place less weight on physical attractiveness when forming trait judgments. All in all, ratings increased in the filter condition, but the predictive power of attractiveness on trait judgments slightly weakened.

In social settings, this becomes evident, as attractive individuals may be treated more favourably or receive greater opportunities and trust from others. As a result, this reinforces the bias over time, as others respond more positively to them, supporting the idea that they possess desirable traits. The halo effect not only shapes opinions but also influences outcomes too, as attractive people may receive more job opportunities or less harsh punishments in court, as outlined by Yang et al. (2019). The researchers concluded that attractive and trustworthy-looking defendants were judged more favourably, while unattractive or untrustworthy defendants received harsher punishments, such as longer prison sentences and greater fines.

In contrast, what is less discussed is the opposite of the halo effect: the horn effect. The horn effect occurs when a single negative trait leads us to form a general negative impression of an individual. Research by Nisbett & Wilson (1977) suggests that negative first impressions can form evaluations, as global judgements influence how certain traits are perceived. This cognitive bias means that a negative trait, such as untidiness, can lead individuals to judge a person as less trustworthy or capable.

All in all, both the halo and horn effects illustrate how first impressions can influence our thinking and, through a psychological lens, highlight how our judgements are not solely rational but are influenced by mental shortcuts that simplify social information. Delving into these cognitive biases can help us become aware of how we evaluate and perceive others, consider our assumptions carefully, and thus make more accurate and fair judgements. 

Written by Shreya Dhaliwal

Related articles: The endowment and nudge effects

REFERENCES

Gulati, A., Martínez-Garcia, M., Fernández, D., Lozano, M. A., Lepri, B., & Oliver, N. (2024). 

What is beautiful is still good: The attractiveness halo effect in the era of beauty filters. Royal Society Open Science, 11(11). https://doi.org/10.1098/rsos.240882.   

Gupta, P. (2020, September 21). Falling in love at first sight easily? The halo and horn effect. Medium. https://parulgupta-40907.medium.com/falling-in-love-at-first-sight-easily-heres-what-you-should-know-about-halo-and-horn-effect-16c7236aeaf6.   

Lasky, J. (2024). Halo Effect. EBSCO. https://www.ebsco.com/research-starters/psychology/halo-effect.

Lenoir, K., & Stocks, E. (2019). Attractiveness norm violations and the halo effect. Undergraduate Journal of Psychology, 31(1).   

Nisbett, R. E., & Wilson, T. D. (1977). The halo effect: Evidence for unconscious alteration of judgments. Journal of Personality and Social Psychology, 35(4), 250–256. https://doi.org/10.1037/0022-3514.35.4.250.  

Yang, Q., Zhu, B., Zhang, Q., Wang, Y., Hu, R., Liu, S., & Sun, D. (2019). Effects of male defendants’ attractiveness and trustworthiness on simulated judicial decisions in two different swindles. Frontiers in Psychology, 10. https://doi.org/10.3389/fpsyg.2019.02160.