Neurocognitive mechanism for morphological complex word processing
ABULIZI Abudukelimu1,2, JIANG Minghu1,2, YAO Dengfeng1,2, ABUDUKELIMU Halidanmu3
1. Laboratory of Computational Linguistics, School of Humanities, Tsinghua University, Beijing 100084, China;
2. Center for Psychology and Cognitive Science, Tsinghua University, Beijing 100084, China;
3. State Key Laboratory of Intelligent Technology and Systems, Tsinghua University, Beijing 100084, China
Abstract：Event-related potentials (ERPs) were used to investigate electrophysiological correlates of Uyghur morphological word processing in lexical decision paradigms. Four stimuli were used with monomorphemic words, bimorphemic inflected nouns (case suffix is added to the stem), monomorphemic pseudowords (changing one or two letters in monomorphemic nouns) and inflected pseudowords (changing one or two letters in stems). The mean phonemic length of all the words was controlled to be six letters long. EEG data showed N400 effects for the bimorphemic complex words and pseudowords in the 350-550 time windows. The N400 effects for the bimorphemic pseudoword were demonstrated that subjects failed all lexical searches when processing bimorphemic pseudowords. The effect for the bimorphemic complex words most probably reflects the access and possible interaction of the stems and suffixs. The EEG data also showed the differences in the neurocognitive underpinning that supports monomorphemic words, bimorphemic inflected words and both types of pseudoword processing. The mean amplitudes for bimorphemic words are more negative in the right hemisphere electrodes than for monomorphemic words. The experimental results reveal that native Uyghur speakers represent and access inflected Uyghur words in a morphologically decomposed form, while monomorphemic words are accessed as a single form.