Parallel phonological processing of Chinese characters revealed by flankers tasks

In this study, we investigate whether readers can process the phonological information of foveal and parafoveal Chinese characters simultaneously. The original and the revised flankers tasks were applied. In both tasks, a foveal target character was presented in isolation in the no-flanker condition, flanked by a parafoveal homophone in the homophone-flanker condition, and flanked by a non-homophonic character in the unrelated-flanker condition. Participants were instructed to fixate on the target characters and press two keys to indicate whether they knew the target characters (lexical vs. non-lexical). In the original flankers task, the stimuli were presented for 150 ms without a post-mask. In the revised flankers task, we set the stimulus exposure time (duration of the stimuli plus the blank interval between the stimuli and the post-mask) to each participant’s lexical decision threshold to prevent participants from processing the target and flanker characters serially. In both tasks, reaction times to the lexical targets were significantly shorter in the homophone-flanker condition than in the unrelated-flanker condition, suggesting parallel phonological processing of Chinese characters. In the revised flankers task, accuracy rates to the lexical targets were significantly lower in the unrelated-flanker condition compared to the homophone-flanker condition, further supporting parallel phonological processing of Chinese characters. Moreover, reaction times to the lexical targets were the shortest in the no-flanker condition in both tasks, reflecting the attention distribution to both the target and flanker characters. The findings of this study provide valuable insights into the parallel processing mechanisms involved in reading.

Stimuli

Experimental procedures

Results

The phonological information of the parafoveal flanker characters not only influenced participants' reactions times, but also accuracy rates to the lexical target characters. This significant phonological POF effect suggested readers can simultaneously process the phonological information of foveal and parafoveal Chinese characters.

Q ＆ A : What is the POF (parafoveal-on-foveal) effect?

Parafoveal-on-foveal effects refer to the possibility that processing of the parafoveal word can influence the fixation durations on the foveal word during reading, which were normally regarded as evidence for parallel lexical processing. 

In the staircase procedure, the duration of ISI varied following the designed algorithm to estimate the ISI threshold for the lexical decision, which was then applied in the revised flankers task.