Word scanning in native and non-native languages: insights into reading with declined accommodation.

This study investigated the effects of declined accommodation on reading performance in non-native and native languages. Eighteen native Japanese speakers participated: eight presbyopes and ten non-presbyopes. In the experiment, participants were asked to scan, or sequentially read six-word items presented in two-line texts, identify a non-word target as quickly as possible, and indicate its location. In addition to the participant type (presbyopes/non-presbyopes) and language of the reading material (Japanese/English), viewing distance (35 cm/70 cm) and contrast (18%/100%) were manipulated. The results showed that the presbyopes exhibited worse reading performance than the non-presbyopes at closer distances irrespective of the language. Notably, the inferiority of the presbyopes' reading performance was more pronounced when they read in a non-native language than in their native language. It should be noted that differences in reading performance between the presbyopes and non-presbyopes were subtle for high-contrast words at longer viewing distances, indicating that age- or cohort-related perceptual, motor, and cognitive differences were almost negligible, but accommodation mattered. These results suggest that the effect of accommodation decline is influenced by the language of the reading material.