Sentence Processing A Sentence Comprehension

Sentence comprehension processes involve more than combining the meaning of individual words in a sensible fashion. Even though the sentence ''the girl chased the dog'' has the same content words as ''the dog chased the girl'' and ''the girl was chased by the dog,'' it is clear that the first sentence means something different than the latter two. Clearly, the grammatical roles that nouns play (e.g., subject vs object) and sentence structure (e.g., active vs passive) play a role in determining sentence meaning. Most models of sentence comprehension assume that in order to understand a sentence, the constituents (e.g., noun phrase, verb phrase, and prepositional phrase) of a sentence must be identified and related to each other structurally. The ''parser'' is the term used to describe the module that assigns syntactic structure to a sentence. Parsing allows the determination of the grammatical roles, such as subject, direct object, and indirect object. These grammatical roles are assumed to be mapped onto ''thematic roles''—that is, conceptual roles that entities play with respect to a verb such as the agent (i.e., the entity carrying out the action), theme (i.e., the entity being acted upon), recipient, or location. The mapping between grammatical roles and thematic roles varies for different verbs and may vary for the same verb depending on the sentence. For example, the thematic roles of the subjects of the phrases ''the boy received,'' ''the girl opened,'' and ''the key opened'' are ''recipient,'' ''agent,'' and ''instrument,'' respectively. Because of this variation in mapping, the lexicon needs to contain verb-specific information concerning the possible mappings between grammatical and thematic roles.

It is often the case that the syntactic structure to be assigned to a sequence of words is ambiguous. For example, for a sentence beginning with ''The defendant examined,'' ''examined'' could be the main verb or could be part of a reduced relative clause construction (e.g., ''The defendant examined by the lawyer was innocent''). A major issue in research on sentence processing has been whether a strict modular approach applies in which the parser assigns syntactic structure purely on the basis of syntactic rules of thumb (e.g., ''choose the simplest structure'') or whether an interaction between semantic and syntactic information affects parsing decisions. For example, if semantic information influences parsing, then ''examined'' should be less likely to be taken as the main verb in a sentence beginning ''The evidence examined'' since ''evidence'' is unlikely an agent of''examine.'' Current evidence supports the interactive view.

During comprehension, it is necessary to integrate different constituents of a sentence, sometimes over distances spanning several words. For example, in the sentence ''The truck that the car splashed was green,'' it is necessary to retrieve ''truck'' as the direct object of ''splashed'' and to integrate ''green'' with ''truck'' rather than ''car.'' Consequently, researchers have assumed that comprehension makes demands on working memory resources. The concept of working memory is similar to that of short-term memory, involving the temporary maintenance of information. The term ''working'' is used to signify that this capacity is used in carrying out computations in addition to maintaining information. Individual differences in working memory capacity of normal individuals have been found to correlate with aspects of sentence comprehension performance. However, neuropsychological findings suggest that there are different components of working memory that play different roles in sentence comprehension.

Aspergers Answers Revealed

Aspergers Answers Revealed

Learn How to Help, Understand amp Cope with your Aspergers Child from a UK Chartered Educational Psychologist. Before beginning any practice relating to Aspergers it is highly recommended that you first obtain the consent and advice of a qualified health,education or social care professional.

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