Memory-Based or Experience-Based? Subject-Object Asymmetry in Mandarin Relative Clause Processing from the Aging Perspective.

The processing difficulty of subject relative clauses (SRCs) and object relative clauses (ORCs) in Mandarin Chinese has been a controversial issue in psycholinguistics. Memory-based accounts and experience-based accounts make contrastive predictions regarding the processing asymmetry. Given that older adults tend to have lower memory and richer language experience, the processing of relative clauses in older adults can reveal which theoretical account offers a more adequate explanation of sentence comprehension. The present study compared the processing of Mandarin SRCs and ORCs in older and younger adults using a self-paced reading paradigm. The results revealed that both groups showed lower accuracy for SRCs than ORCs, but this effect was larger in older adults. These age-related differences cannot be attributed to different strategic trade-off mechanisms and task experience. During online processing, older adults performed more slowly than younger adults, but no significant interaction was found between age and RC type. These findings suggest that aging affects sentence comprehension at the post-interpretive and decision processes, while online syntactic processing remains relatively preserved but globally slowed. The findings are largely consistent with memory-based accounts, indicating that age-related changes in sentence comprehension may be attributed to memory decline in older adults.