Two types of ambiguities commonly encountered during sentence comprehension are lexical and syntactic ambiguities. Disambiguation is typically achieved easily, as it is aided by language cues, such as the frequency of occurrence and/or the plausibility of interpretation with relation to the surrounding context. This research will investigate the use of frequency and plausibility cues within lexical and syntactic ambiguities, as a function of working memory capacity. Frequency cues will be manipulated while plausibility cues are held constant, and vice versa, in high and low working memory groups. An individual's ability to resolve ambiguities will be calculated by comparing ambiguous sentences to unambiguous control sentences using a self-paced reading paradigm, previously shown to be sensitive to ambiguity effects and differences in working memory capacity.
The first aim i s to investigate whether a common cognitive mechanism is utilized when resolving these ambiguities. In the 1990s, lexical processing, syntactic processing, and language cues were proposed to utilize a single mechanism. This idea countered the concept of modularity proposed by Fodor in the 1980s. No work has been published to test whether a single mechanism is used to resolve these ambiguities, despite significant implications for language processing models and theories.
The second aim i s to determine whether frequency cues are used to a greater extent than plausibility cues within an individual, as plausibility cues may be more difficult to process.
The third aim i s to determine whether frequency and plausibility cues are used differently in sentence processing as a function of working memory, as individuals with low working memory may have increased difficulty processing language cues. The results of this research will increase scientific knowledge of normal ambiguity resolution in sentence processing, and the cognitive resources that support ambiguity resolution. Previous research has suggested that ambiguities in sentence comprehension are disambiguated by language cues and mediated by an individual's working memory capacity. The goal of this research is to further the pursuit of fundamental knowledge regarding the mechanisms that support the disambiguation of lexical and syntactic ambiguities as a function of working memory capacity. The results of this research may be applied to the development of more detailed models of normal language processing, which may lead to better diagnostic tools and treatment programs for rehabilitating persons with disordered language and improving their quality of life. ? ? ?