[4][5] According to conceptual metaphor theory, people think in terms of frames that are physically realized in the neurocircuitry of the brain.
A part in the brain for quantity and another for verticality are frequently activated together forming a circuit that combines both concepts.
Specifically, Boulenger, Shtyrov, and Pulvermuller (2012)[10] and others[11] found that metaphors depicting a physical activity ("she grasped the idea" or "kick the habit") are processed through the brain's motor cortex much faster than literal language.
Therefore, people need to have some amount of prior knowledge about both the source and target domains for metaphorical framing to be successful.
The researchers found that, on the one hand, participants who read the "crime is a beast" metaphor were more likely to support crime-fighting strategies such as increasing the number of police officers and building more jails.
A follow-up study demonstrated that participants were unaware of the influence of the metaphorical frame on their attitudes toward crime.
It is important to note, here, that recent evidence suggests that this particular metaphor is not as effective when compared to a control group.
[21] Specifically, Steen, Reijnierse, and Burgers (2014) find that people tend to favor crime-fighting strategies irrespective of the frame they were presented.
[24] For instance, Santa Ana (1999) analyzed the newspaper Los Angeles Times during their coverage of the 1994 political debate over California's anti-immigrant Proposition 187 that would have prevented undocumented Californians from using state services.
Santa Ana found that in their coverage, the LA Times frequently framed immigrants as animals (e.g., "The truth is, employers, hungering for really cheap labor hunt out the foreign workers" and "Once the electorate's appetite has been whet with the red meat of deportation as a viable policy option").
Research also shows that metaphorically framing immigration as a flood (e.g., a wave of refugees) can increase support for a wall at the US-Mexico border.
[25] In this example, researchers conducted a content analysis of social media posts (i.e., tweets) and also experimentally exposed people to a frame describing immigration in terms of a flood or a control group.
People then use the heightened mental association of flood-levee to think about immigration as refugee-wall—thus espousing greater support for a border wall.
[27] In this study, researchers exposed participants to three conditions of a news article describing climate change.
In one condition, participants read climate change framed as a war (e.g., "the entire country should be recruited to fight this deadly battle").