Facilitation and Interference Components of the Size Congruity Effect in College Students

Document Type


Degree Name

Doctor of Philosophy (Ph.D)


Educational Psychology

Date of Award

Fall 2016


The present study examined the facilitation and interference components of the size congruity effect in college students. In Experiment 1, computer mousetracking was used to capture the trajectories of responses during a numerical size congruity task in which participants were asked to select the physically larger of two digits. Response time and trajectory data supported the conclusion that numerical magnitude is automatically processed, and that the decision process continues through the motor response, consistent with the late interaction model (Faulkenberry, Cruise, Lavro, & Shaki, 2016; Santens & Verguts, 2011; Sobel, Puri, & Faulkenberry, 2016; Sobel, Puri, Faulkenberry, & Dague, in press). In Experiment 2, participants completed the Calculation Fluency Test (Sowinsky, Dunbar, & LeFevre, 2014) and the Brief Mathematics Assessment – 3 (Steiner & Ashcraft, 2012) as measures of math achievement and Form A of the abbreviated Standard Progressive Matrices test (Bilker et al., 2012) as a measure of fluid intelligence in addition to the experimental task used in Experiment 1. There were no significant findings related to fluid intelligence. Individuals with a previous diagnosis of learning disorder or attention deficit hyperactivity disorder had lower scores on measures of math achievement. Analysis of the size congruity effect replicated the findings of Experiment 1, again providing support for the automatic representation of numerical magnitude and the late interaction model. Neither facilitation nor interference was found to be significant in predicting math achievement. Facilitation and interference were evident in trajectory measures even when undiscernible in movement and initiation time, which demonstrates the value of computer mousetracking over response time alone in examining covert cognitive processes.


Tracy B. Henley

Subject Categories

Education | Educational Psychology