This article was originally published on The Psych Report before it became part of the Behavioral Scientist in 2017.

In this article, we review five works that influenced psychology’s understanding of metaphor. Together these five works introduce the field of metaphor research and illustrate several key findings: the ubiquity of metaphors in daily life, how metaphors evolve within a language, and how metaphors can subtly influence perception, speech, and even decision making.

Imagine the following:

It’s been another busy week at work, and you’ve just sat down to watch dozens of Friends reruns curled up on your couch, when you get an email from your boss.

Great. Now you have to get your presentation ready by Monday. You put on some pants and call your colleague. She answers with a tone of misplaced peppiness, which you can only attribute to her blissful ignorance of the rescheduled meeting. Did you hear? Wednesday’s meeting has been moved to Monday. No, reread the email. It says Monday! Oh wait, it says “forward two days.” No, but that means the meeting is on Monday! I’m calling Cheryl. Your colleague thought the meeting was moved to Friday. You thought it was moved to Monday. The confusion here is not uncommon, and is inherently rooted in our choice of language.

Now imagine a second scenario: You are tasked with solving the crime problem in the city of Addison. On your first day, a colleague hands you the following report:

“Crime is a beast ravaging the city of Addison. Five years ago Addison was in good shape, with no obvious vulnerabilities. Unfortunately, in the past five years the city’s defense systems have weakened, and the city has succumbed to crime. Today, there are more than 55,000 criminal incidents a year – up by more than 10,000 per year. There is a worry that if the city does not regain its strength soon, even more serious problems may start to develop.” [footnoote, with explanation of experiment 2]

What solutions would you recommend to address Addison’s problem with crime? Would your recommendations change if the first sentence of the above report read “Crime is a virus…,” rather than “Crime is a beast…?” Recent research on metaphor suggests it would.

Complex social issues like crime cannot be easily expressed. Neither can abstract concepts like time, nor many of the things and situations we need to describe and communicate on a daily basis. That is where metaphors come in. Across all cultures and languages, humans use metaphors to describe diverse concepts such as time, crime, emotions, and motion (Lakoff and Johnson, 1980). But metaphors are more than just eloquent descriptions.

Research has shown that metaphors impact speech, perception, neural activity, and decision making in a substantially different, and often surprising way, compared to regular language. The five works reviewed below introduce the field of metaphor research and illustrate key findings in the field: the ubiquity of metaphors in daily life, how metaphors evolve within a language, and how metaphors can profoundly influence perception, speech, even decision making.

1: The Role of Mind and Body in Abstract Thought

Lera Boroditsky and Michael Ramscar (2002) examined metaphor by asking a variety of people that same ambiguous question from the email above: “Suppose you are told that next Wednesday’s meeting has been moved forward 2 days. What day is the meeting now that it has been rescheduled?” Embedded in this question is a pervasive, but ambiguous, metaphor in the English language, describing time in terms of space. (The ambiguity comes from two ways of conceptualizing time. In one case, time is a destination that you move towards. In another, you are stationary and time moves towards you: For example, “The holiday season is approaching” or “We’re approaching the holiday season”). What Boroditsky and Ramscar found was that a participant’s answer to the question above depended on his/her current experience and movement through space.

In a series of 4 experiments, Boroditsky and Ramscar asked groups of people, experiencing different types of motion, the same question about the meeting date. In one experiment, they presented San Francisco airport-goers with the ambiguous question. Those who had just landed at the airport were most likely to choose Friday and thus adopt a self-moving metaphor, time as destination. People who were just about to take off also chose Friday more, but the effect was slightly less. And those who were waiting to pick someone up at the airport were equally likely to say Monday or Friday. The authors posit that an individual’s conception of time may be influenced by their physical movement through space. Most of those who just landed and most of those about to take off conceptualized time using a self-moving metaphor; when an event in time is a destination, and the individual moves through time. In this case, a meeting that was moved forward by two days would be two days farther in front of the individual, on Friday. Those who responded Monday likely conceptualized time as flowing past a stationary self. In that case, a meeting moved forward in time would be two days earlier, on Monday. Boroditsky and Ramscar found this pattern of answers held across different contexts; whether moving forward in a lunch line, a train, or an office chair.

Whether an individual is rushing through life, or time is flying by, Boroditsky and Ramscar’s research illustrates how a seemingly objective question is actually quite subjective, and people’s answers can be different depending on their metaphoric interpretation of time and space.

Boroditsky, L. & Ramscar, M. (2002). The Roles of Body and Mind in Abstract Thought. Psychological Science, 13(2), 185-188.

2: Metaphors We Live By

Twenty years before Boroditsky and Ramscar published their investigation of time metaphors, George Lakoff and Mark Johnson helped lay the foundation for metaphor research with their book, Metaphors We Live By (1980). In their book, Lakoff and Johnson suggest that thinking of one concept in the abstracted terms of another is a powerful tool that humans use and one that is central to human cognition.

This ubiquity of metaphor is illustrated with their classic example of the argument-is-war metaphor. Arguments can be won or lost. Claims can be attacked or defended. Points can be right on target. People, they suggest, structure their descriptions of one concept using the familiar language from another concept, as an efficient way to point out relational similarities between two seemingly distant ideas. Furthermore, Lakoff and Johnson question how the world may be different if the metaphors were different; if it were more common to compare an argument to a dance–something elegant and cooperative, rather than combative and harsh.

Lakoff and Johnson also point out that even many of the words that appear to have literal meaning were once metaphoric from some earlier iteration of the word. Take the word obligation–a duty or a responsibility. This word is actually a metaphoric expansion of the Latin usage, which comes from a word meaning, literally, a binding. Over time, this metaphor has been conventionalized and turned into something that seems literal today.

In Metaphors We Live By, Lakoff and Johnson explore the power of metaphor in shaping human language and cognition. Though not without its controversy, Metaphors We Live By inspired decades of research and theories about how metaphors influence human cognition.

Lakoff, G., & Johnson, M. (1980). Metaphors we live by. 1980. Chicago: U of Chicago Press.

3: The Career of Metaphor

Another influential force in the field of metaphor has been the research of Brian Bowdle and Dedre Gentner. In a 2005 study, they found that metaphors can become embedded in language over time, such that the metaphor no longer carries a comparison but is understood as a literal statement. In their study, Bowdle and Gentner presented novel or conventional metaphors and stimuli to participants. Conventional metaphors are the inconspicuous, everyday metaphors (e.g. our love is a drug), whereas novel metaphors are the ornamental, and imagery-rich metaphors (e.g. our love is a fruit). Usually, conventional metaphors can be quickly understood, whereas novel metaphors require an unfamiliar comparison between two concepts.

Bowdle and Gentner measured reaction time in order to test how quickly people processed and understood different novel and conventional lingual comparisons, similes and metaphors. As they hypothesized, novel similes were comprehended faster than novel metaphors. (e.g. our love is like a fruit vs. our love is a fruit) However, the opposite was true for conventional comparisons. Conventional metaphors were comprehended faster than conventional similes. (e.g. our love is a drug vs. our love is like a drug) These results led Bowdle and Gentner to propose the Career of Metaphor hypothesis. This theory argues that, as a metaphor becomes more and more conventionalized, the mode of processing shifts from a time-consuming comparison to a faster categorization method. Eventually, they argue, a metaphor that has become so conventionalized becomes a “dead” metaphor and is comprehended essentially as a literal statement. After all, nobody thinks of literal bondage when they hear the word obligation.

Bowdle, B. F., & Gentner, D. (2005). The career of metaphor. Psychological Review, 112(1), 193.

4: The time-course of metaphor comprehension: An event-related potential study

In one of the earliest neuroimaging studies of metaphor Pynte, Besson, Robichon, and Poli (1996) examined participants electroencephalogram (EEG) recordings while they read sentences containing metaphors. Participants read sentences that either contained familiar metaphors, unfamiliar metaphors, or literal [control] sentences. During the presentation of the sentences, the researchers recorded electrical activity along the participant’s scalp using an EEG system. Going into the experiment, the researchers knew that every time an individual reads a word there is a measurable brain response 400 milliseconds later. This response is referred to as an N400 and is thought to be a neural indication of comprehension of that word. Pynte and colleagues found larger N400 responses for words used in metaphoric contexts than in literal contexts. This was one of the first experiments to suggest that our brain is doing something quantifiably different when we read metaphoric sentences. Since this initial study, and with increased neuroimaging technology, researchers have recently expanded the methods and improved the techniques for acquiring clean, reliable data about our surges of our brain’s electrical activity when we are exposed to different metaphors, in order to understand how metaphors work at a neural level.

Pynte, J., Besson, M., Robichon, F. H., & Poli, J. (1996). The time-course of metaphor comprehension: An event-related potential study. Brain and Language, 55(3), 293-316.

5: Metaphors We Think With: The Role of Metaphor in Reasoning

So, is crime a virus or a beast? A recent study by Paul Thibodeau and Lera Boroditsky (2011) begins to unravel the tangle between language, thought, and decisions making. In a series of experiments, Thibodeau and Boroditsky examined how using two different metaphors to describe the exact same problem of crime can prime people to suggest different solutions to the same problem. Participants were presented with the paragraph below. The first sentence contained either the word “beast” or the word “virus.” They were then asked to identify solutions to Addison’s crime problem.

“Crime is a {beast/virus} ravaging the city of Addison. Five years ago Addison was in good shape, with no obvious vulnerabilities. Unfortunately, in the past five years the city’s defense systems have weakened, and the city has succumbed to crime. Today, there are more than 55,000 criminal incidents a year – up by more than 10,000 per year. There is a worry that if the city does not regain its strength soon, even more serious problems may start to develop.”

Thibodeau and Boroditsky found that people’s suggestions about solutions to the crime problem in Addison were significantly different depending on the metaphor with which they were primed. Those who who read “Crime is a beast…” were more likely to suggest enforcement-based solutions (i.e. more police force, longer sentencing for violators, etc.). Those who read “Crime is a virus…” were more likely to suggest education initiatives or economic policy changes. Remember, this is despite the fact that each description of Addison contains the exact same objective statistics about crime.

The reasons why the virus or beast metaphors affect how people think about crime may be somewhat intuitive when one considers the possible solutions for dealing with viruses or beasts. When thinking about solutions for beasts, thoughts of cages, enforcement, and brute force arise as answers to the problem. When thinking about solutions for viruses, thoughts of antidotes and preventions, and social reform emerge as answers.

Lastly, Thibodeau and Boroditsky report that people rarely identified the metaphor as being influential to their solution for Addison’s crime problem, which illustrates the subtle power of metaphors to influence decision making. This research adds to the growing body of literature showing that using different metaphors to frame a situation can prime people to conceptualize that scenario in completely different ways.

Thibodeau, P. H., & Boroditsky, L. (2011). Metaphors we think with: The role of metaphor in reasoning. PLoS One, 6(2), e16782.

This article has been updated.