Effect of two trigram-words displayed at different visual angles on word recognition accuracy and reaction time

摘要

The objectives of this study were to study visual recognition accuracy (correct rate – CR) of reading andreaction time (RT) responses when two trigram-words presented at different visual angles. Thirty graduatestudents were recruited. Each pair of trigram-words were shown at 1, 2, and 3 degrees of arc from the centerof the fovea (horizontal visual angles of 2, 4, and 6 degrees), in three experimental blocks. Each block used atotal 180 pairs of trigram-words comprising Type 1 (two identical trigram-words, e.g. “pan-pan”), Type 2(two completely different trigram-words, e.g. “pan-box”), and Type 3 (different only the middle letter oftrigram-words, e.g. “pan-pin”) stimuli. The participants were instructed to press button “1” if the two-wordsshown were identical, and press button “2” if they were different, as quickly as possible. CRs and RTs wererecorded. The results showed that CR of Type 1 stimuli was highest at 2 degree apart when compared withthose at 4 and 6 degrees apart, indicating that two identical words could be identified best at the foveal edge(at the edge of 2 degrees in diameter). At 6 degree, CR of Type 2 stimuli was highest, followed by Type 3 andType 1 stimuli, respectively, indicating that at peripheral vision, completely different words could be easiestidentified. Moreover, RTs of Type 2 stimuli were shortest, and CRs of Type 2 stimuli were highest in everyvisual angle. These findings were the first to show that completely different words recognitions were notaffected by wider visual angles, possibly caused by orthographic processing of different word shapes. Thesedata can be used for further developing reading training software for improving visual span.