Form perception speed is critical for the relationship between non-verbal number sense and arithmetic fluency

Form perception has been found to be critical for arithmetic fluency. How visual processing of form is related to arithmetic fluency is a question that remains to be answered. The current study hypothesized that form perception speed correlates with arithmetic fluency. Experiment 1 applied a between-subject design. 227 fifth grade students were recruited and randomly divided into two experimental groups. The groups performed the same figure-matching task, but with different stimulus durations: 400 ms or 1000 ms. The results showed that the 400 ms group had greater arithmetic fluency than the 1000 ms group, and form perception measured only in 400 ms group could explain the relationship between non-verbal number sense and arithmetic fluency. Experiment 2 applied a within-subject design. 245 fifth-grade students were recruited and all participants were administered a 400-ms figure-matching task and a 1000-ms figure-matching task. The form perception measured with 400 ms or 1000 ms duration could explain the relationship between non-verbal number sense and arithmetic fluency. These findings indicate that form perception speed underlies the association among form perception, non-verbal number sense, and arithmetic fluency.