Creative Commons License

Creative Commons License
This work is licensed under a Creative Commons Attribution-Noncommercial-No Derivative Works 4.0 License.

Preferred Name

Chris Hill

Date of Award

Fall 2017

Document Type


Degree Name

Doctor of Psychology (PsyD)


Department of Graduate Psychology


Gregg Henriques

Craig Shealy

Kenneth Critchfield


Given the current state of the literature and weaknesses of many previous prevalence studies, the primary purpose of this research study was to gather base-rate data of color-grapheme synesthesia in a general population sample. Over a period of seven months, 502 participants enrolled in the study on Mechanical Turk and completed the online Synesthesia Battery. The primary data collected was the participant’s score on the synesthesia test, whereby a score of a one or below is deemed by the battery to be indicative of someone with a color-grapheme synesthetic ability. Of the 502 participants, eight percent (0.082) of the population sampled had scores below one, the cutoff suggestive of synesthesia on the Synesthesia Battery. This is a much higher percentage of the population than previously reported by previous studies. Exploratory analyses of demographic variables revealed some significant findings for handedness and education, such that left-handed people may have a greater representation among synesthetes than right-handed people and participants meeting the one score cutoff suggestive of synesthesia were more likely to have a graduate education.

Included in

Psychology Commons



To view the content in your browser, please download Adobe Reader or, alternately,
you may Download the file to your hard drive.

NOTE: The latest versions of Adobe Reader do not support viewing PDF files within Firefox on Mac OS and if you are using a modern (Intel) Mac, there is no official plugin for viewing PDF files within the browser window.