Number of sense effects of Chinese disyllabic compounds in the two hemispheres (original) (raw)
Related papers
Frontiers in Psychology
In English, an extensive body of work in both behavioral and neuropsychological domains has produced strong evidence that homonymy (words with many distinct meanings) and polysemy (many related senses) are represented, retrieved, and processed differently in the human brain. In Chinese, most words are compounds, and the constituent characters within a compound word can have different meanings and/or related senses on their own. Thus, in order to resolve lexical ambiguity in Chinese, one has to consider the composition of constituent characters, as well as how they contribute to whole word reading, known as "sublexical ambiguity." This study investigates how two types of sublexical ambiguity affect Chinese word processing. The number of meanings (NOM) and the number of senses (NOS) corresponding to the first character of Chinese compounds were manipulated in a lexical decision task. The interactions between NOM and NOS were observed in both behavioral results and N400s, in which NOM disadvantage effect was found for words with few-senses only. On the other hand, the NOS facilitation effect was significant for words with multiplemeanings (NOM > 1) only. The sublexical ambiguity disadvantage suggested that semantically unrelated morphemes are represented as separate entries. For characters with multiple meanings, one orthographic form is associated with more than one morphemic representation. In contrast, the sublexical sense advantage supported the idea that semantically related senses that shared a morphological root are represented within a single entry. The more senses listed in a morphological root, the stronger representation will be formed. These results suggest that two types of sublexical ambiguities are represented and processed differently in Chinese word recognition models and also demonstrate that how they interact with each other in the mental lexicon.
Sublexical ambiguity effect in reading Chinese disyllabic compounds
Brain and language, 2011
For Chinese compounds, neighbors can share either both orthographic forms and meanings, or orthographic forms only. In this study, central presentation and visual half-field (VF) presentation methods were used in conjunction with ERP measures to investigate how readers solve the sublexical semantic ambiguity of the first constituent character in reading a disyllabic compound. The sublexical ambiguity of the first character was manipulated while the orthographic neighborhood sizes of the first and second character (NS1, NS2) were controlled. Subjective rating of number of meanings corresponding to a character was used as an index of sublexical ambiguity. Results showed that low sublexical ambiguity words elicited a more negative N400 than high sublexical ambiguity words when words were centrally presented. Similar patterns were found when words were presented to the left VF. Interestingly, different patterns were observed for pseudowords. With left VF presentation, high sublexical ambiguity psudowords showed a more negative N400 than low sublexical ambiguity pseudowords. In contrast, with right VF presentation, low sublexical ambiguity pseudowords showed a more negative N400 than high sublexical ambiguity pseudowords. These findings indicate that a level of morphological representation between form and meaning needs to be established and refined in Chinese. In addition, hemispheric asymmetries in the use of word information in ambiguity resolution should be taken into account, even at sublexical level.
Controlled semantic processes within and between the two cerebral hemispheres
Laterality: Asymmetries of Body, Brain and Cognition, 2015
To test the separate and combined abilities of the two cerebral hemispheres to perform controlled semantic selection and integration processes, Hebrew readers saw pairs of words and had to decide whether the two words were semantically related. The first word in each pair was presented centrally. The second word was presented in the left, right, or central visual field (LVF, RVF, and CVF). We compared response latencies for related pairs in two conditions: In the ambiguous condition, the first word was a homograph (either homophonic or heterophonic) and the second word was related to either its dominant or subordinate meaning. In the unambiguous condition, homographs were replaced with unambiguous control words. Irrespective of VF or homograph type, response times for ambiguous pairs were significantly longer than for unambiguous pairs only when targets were related to the subordinate meaning of the homograph. In the left hemisphere (RVF/LH), this ambiguity effect was larger for heterophones than for homophones, whereas in the right hemisphere (LVF/RH), similar patterns were observed for both types of homographs. Finally, performance patterns in the CVF revealed the same patterns as those in the RVF/LH, and were different from those in the LVF/RH. The implications of these results are discussed.
Brain and Language, 2008
The present study examined the manner in which both hemispheres utilize prior semantic context and relative meaning frequency during the processing of homographs. Participants read sentences biased toward the dominant or the subordinate meaning of their final homograph, or unbiased neutral sentences, and performed a lexical decision task on lateralized targets presented 250 ms after the onset of the sentence-final ambiguous prime. Targets were either related to the dominant or the subordinate meaning of the preceding homograph, or unrelated to it. Performance asymmetry was found in the absence of a biasing context: dominant-related targets were exclusively facilitated in the RVF/LH, whereas both dominant-and subordinate-related targets were facilitated in the LVF/RH. Performance symmetry was found in the presence of a biasing context: dominant-related targets were exclusively activated in dominant-biasing contexts, whereas both dominant-and subordinate-related targets were facilitated in subordinate-biasing contexts. The implications of the results for both general and hemispheric models of word processing are discussed.
Differences and Interactions Between Cerebral Hemispheres When Processing Ambiguous Words
Lecture Notes in Computer Science, 2007
It is well known that the brain (especially the cortex) is structurally separable into two hemispheres. Many neuropsychological studies show that the process of ambiguity resolution requires the intact functioning of both cerebral hemispheres. Moreover, these studies suggest that while the Left Hemisphere (LH) quickly selects one alternative, the Right Hemisphere (RH) maintains alternate meanings. However, these hemispheres are connected through the corpus callosum and presumably the exchange of information is useful. In addition, many works show that the Left Hemisphere (LH) is more influenced by the phonological aspect of written words whereas lexical processing in the Right Hemisphere (RH) is more sensitive to visual form. This distinction suggests that the interconnections between the hemispheres may be used to strengthen or correct incorrect interpretations by one hemisphere. We test this hypothesis by (I) postulating that in the Left Hemisphere (LH) orthography, phonology and semantics are interconnected while (II) the Right Hemisphere (RH), phonology is not connected directly to orthography and hence its influence must be mitigated by semantical processing (III) seeing if corrections in ambiguous word processing can be aided by information in the other hemisphere. We investigate this by complementary human psychophysical experiments and by dual (one RH and one LH) computational neural network model architecturally modified from Kawamoto's (1993) model to follow our hypothesis. Since the different models have different rates of convergence, we test (III) by halting processing, and using an analogue to priming to compare the rate of convergence to a corrected semantics in the LH working alone and working with information obtained from the RH at the same point in processing. In this paper we present results of the computational model and show that (I) the results obtained from the two hemispheres separately are analogous to the human experiments and (II) the use of the RH information does indeed help such corrections.
Aphasiology, 2006
Background-Drawing heavily on results from studies with divided visual field (dvf) presentation, current models of hemispheric differences in word semantic processing converge on a proposal (henceforth, "the standard model") that is increasingly being applied in studies of individuals with brain damage. According to this model, left hemisphere processes focus word meanings to their core, whereas right hemisphere processes keep wider representations active. Aims-This paper has three aims: (a) to raise concerns about methodological aspects of the dvf studies that are usually cited in support for the standard model, specifically assumptions about interpretation of lateral dvf prime presentation and priming measures; (b) to highlight areas of further research and theoretical clarification, with reference to studies with central presentation and general models of word-meaning processing; and (c) to discuss the implications of these concerns for deriving a model of hemispheric differences in word-meaning processing, using evidence from paired word priming studies as an example. Main Contribution-The paper discusses problematic assumptions about paired word priming studies of hemispheric contributions to word semantic processing and proposes further research to clarify these assumptions. Furthermore, it introduces an alternative interpretation of the available data, which provides a more parsimonious account of hemispheric engagement in the paired word semantic priming task. Conclusions-Current evidence about hemispheric differences in word-meaning processing is far from conclusive. It is important to consider alternative interpretations of the available evidence when applying models based on this evidence to the study of language disorders. The alternative account proposed in this paper suggests that LH processing, rather than generally reducing activated word meanings to their core, is important for maintaining meanings that are unambiguous and consistent.
Sentence context and lexical ambiguity resolution by the two hemispheres
Neuropsychologia, 1998
A lexical decision experiment investigated hemisphere asymmetries in resolving lexical ambiguity within a sentence context. Sentences that biased a single meaning (either dominant or subordinate) of sentence-final ambiguous words were followed by a lateralized target related to the sentence-congruent or -incongruent meaning of the ambiguous word, or an unrelated word. In the RVF sentence-congruent targets were facilitated, while incongruent targets were not primed. In contrast, related targets were facilitated in the LVF, regardless of sentence context. This suggests that selecting the contextually appropriate word meaning requires the left hemisphere, and supports a right hemisphere role in maintaining alternate word senses.
Overlap and dissociation of semantic processing of chinese characters
2000
The functional anatomy of Chinese character processing was investigated using fMRI. Right-handed Mandarin-English bilingual participants made either semantic or perceptual size judgements with characters and pictures. Areas jointly activated by character and picture semantic tasks compared to size judgement tasks included the left prefrontal region (BA 9, 44, 45), left posterior temporal, left fusiform, and left parietal regions. Character processing produced greater activation than picture processing in the left mid and posterior temporal as well as left prefrontal regions. The lateral occipital regions were more active during picture semantic processing than character semantic processing. A similar pattern of activation and contrasts was observed when English words and pictures were compared in another set of bilingual participants. However, there was less contrast between word and picture semantic processing than between character and picture processing in the left prefrontal region. When character and word semantic processing were compared directly in a third group, the loci of activation peaks was similar in both languages but Chinese character semantic processing was associated with a larger MR signal change. The semantic processing of Chinese characters, English words, and pictures activates a common semantic system within which there are modality-specific differences. The semantic processing of Chinese characters more closely resembles English words than pictures.