语音意识缺陷儿童的言语知觉技能

Considerable studies find that developmental dyslexia is associated with deficits in phonological processing skills, especially phonological awareness. In order to explore the nature of phonological awareness deficits in dyslexia, researchers have begun to investigate the role of speech perception. The findings about speech perception abilities in dyslexics are inconsistent. The heterogeneity of dyslexia may be responsible for the inconsistency of findings. Considering the general suggestion that phonological awareness deficits in dyslexia are attributed to categorical perception deficits, it is more direct to examine whether children with phonological awareness difficulties or phonological dyslexia show speech categorization deficits consistently. The present study would investigate whether Chinese children with phonological awareness deficits or phonological dyslexia showed abnormal speech perception. The whole study consisted of two parts. Part I screened children with phonological-awareness deficits from Year 3 kindergartens and examined their abilities of perceiving native category continuum, nonnative category contrasts and non-speech sound series. Part II selected phonological dyslexics from an elementary school as participants, and further explored the relation between phonological deficits and speech perception. The first two experiments of Part II examined separately the abilities to label stimuli in native category continuum and brief stops in different contexts, the last experiment investigated the adaptation effects of different participant groups. The main conclusions are as follows: 1) Children with phonological dyslexia showed categorical perception deficits: they had lower consistency than controls when perceiving stimuli within phonetic categories, especially for the stimuli which were not natural sounds. 2) Children with phonological dyslexia exhibited a general difficulty of perceiving brief segments of stops from different contexts. 3) Children with phonological dyslexia did not show adaptation to repeatedly presented stimuli. Based on the present conclusions and the findings of previous studies, we suggested that the representations of sound stimuli in phonological dyslexics’ brains are different from those in normal children’s; the representations of sound stimuli in dyslexics’ cortical neural networks are more diffuse and inconsistent.

空间关系类别的形成与计算

Spatial categorization and computation were studied systematically and sequentially in the dissertation, in which, category learning paradigm was transferred to spatial domain. Four parts were developed in our study, in which, the former two parts investigated the mechanism of spatial categorization, and the latter two parts explored two applied issues. Spatial category formation was investigated by two aspects in distance and angle respectively in research one. The results showed that subjects can make accurate judgment and rating for corresponding spatial categorical prototypes and boundaries. In the second research, the formation of spatial relationship categorization was examined through two factors of number of categories and different spatial configurations. The results were repeated in this part, and also, different influences of reference of frame were found in the process of spatial categorization. In the third research, the influences of spatial categorization on spatial localization were found, that in subject could make different location judgment with new acquired spatial categories. Spatial position distribution has no effect on spatial localization on the other hand. The result that reference objects have significant influences on applicability of spatial relationship was found in research four. Our Bayesian hierarchical model could be applied in simulation and prediction of perception of “above” spatial relationship. Theoretical significance and applied importance were discussed in detail.