Date of Graduation

Spring 2023


Master of Science in Psychology



Committee Chair

Bogdan Kostic


Accurate and quick license plate recall is important for identification purposes, especially in emergency situations, such as hit-and-runs. Previous research has shown that there are particular patterns of license plate designs that are easier to recall, such as a higher digit to letter ratio. Missouri license plate patterns (AB1-C2D) somewhat diverge from what research suggests works best for recall. The current study sought to determine if including color into license plate designs would improve recall. There were 48 undergraduate students from Missouri State University who participated in the experiment. Participants saw 100 timed trials of license plate stimuli, where they saw the stimuli for half a second, waited six seconds, then had 10 seconds to recall the license plate stimulus they saw. Participants randomly saw one of two formats for the license plate stimuli; either the digits in the stimuli would be in color or the stimuli would be in all-black text. The hypothesis that the inclusion of color would improve recall was not supported, as there were no significant differences in recall between the two groups based on format. While color may be useful, future research should continue to look for additional ways to improve designs that would be easy to implement.


license plates, memory recall, license plate design, color effects

Subject Categories



© Hannah R. Johnson

Open Access

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Psychology Commons