Auditory Processing of Farsi words, Pseudowords and Nonwords

During the recent two decades, the subject of processing well-formed and ill-formed words have been exploited in the literature for different languages and different purposes. Lexical retrieval for auditory inputs has been proved to start as soon as 200 ms after the stimulus onset. However, the questions of when and how well-formed and ill-formed words change their processing paths have yet to be answered for Farsi speakers. In this study, Farsi speakers did a lexical decision task while their brain activity was being recorded by a 64 channel EEG. The stimuli included Farsi words, pseudowords and nonwords, which were very similar in structure and were consistent in terms of fundamental frequency, intensity and duration. The ERP data showed an LPC for nonwords in frontal regions, which is known to be an indicator of violating phonotactic constraints. In addition, nonwords and pseudowords showed almost equal N400 effects in parietal regions, which can reflect a more effortful semantic integration compared with words. Finally, the peak latency analysis revealed an earlier N400 peak for pseudowords as opposed to words and nonwords. The regions where N400 and LPC were identified differed from some studies in the literature.