Syntactic Movement and Length Effect: An Eye-tracking Analysis

constituent ordering, is not arbitrary; rather, it is aimed at fulfilling efficiency principles. Length effect- as a formal characteristic- is a significant determinant in the occurrence of movement rules. The ultimate structural configuration of sentences is interwoven with processing ease. Adopting eye movement registration technique, the current research study aims to explore eye behavior in response to processing difficulty of syntactically different but semantically identical sentences and provide behavioral evidence for the effect of length on the occurrence of movement in structural sentence pairs in Persian. Encompassing two syntactic movements (relative clause extraposition and postposing) through 2 sets of 40 sentence pairs in two length levels (short and long), some eye behavior such as fixation count/duration and regression were registered and analyzed using SPSS. Regarding the patterns of fixation, when the constituents under study were short, there was either no significant difference before and after the occurrence of syntactic movement, or the mean of fixation count and duration was lower in sentences with canonical constituent ordering; however, the patterns appeared to be reversed and hence a significant difference was spotted by the increase of constituent length. Regarding regressions, the mean regressions declined after the post-verbal movement of constituents by the increase of length. It can be concluded that syntactic movement is weight-sensitive and aimed at easing processing difficulty. Also, the likelihood of post-verbal movement in extraposition and scrambling increases by the rise of length and driven by the incentive of increase of processing efficiency.