Notes for Chapter 9 Semantic Memory
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1. Let us consider the words canary, robin, penguin, and piano. As speakers of English we know many things about canary. We know that it refers to a kind of bird. We know that the thing it refers to is often yellow, has wings, has a heart, and is warm-blooded. We know that canaries fly, sing, and lay eggs. We know that a robin is a kind of bird, is warm-blooded, has a red breast, flies, has a heart, eats worms and lays eggs. We know that a penguin is a kind of bird, is warm-blooded, swims, eats fish, and lays eggs. We know that the kind of object piano refers to, is quite different from all of these.
2. How do we represent the knowledge that we all have about words? There are many redundancies, and we know of many relationships among them. Does that mean that words with similar meanings are in some sense share parts of their meaning representation? By what process or algorithm do we identify appropriate relationships? In order to demonstrate our knowledge, either directly by answering questions about it, or indirectly, by using the meaningful information appropriately, we must have access to and be able to operate on the right information.
3. #1 and #2 lead us to consider how lexical information is structured in memory and what the processes are that we use to interrogate that memory. We certainly feel that some of the things that we know about these concepts we did not learn directly, but we could figure it out. From a reasoning or problem solving, or computational perspective, we have to be able to identify some procedure (recursive process) which can effectively do the task.
4. Lexical items are of various sorts. The parts of speech in grammar help somewhat, but does not designate all of the differences that seem to exist. Content words such as nouns, verbs, and adjectives function differently from function words like prepositions, pronouns, and conjunctions. Each of these categories have words which function differently from one another. I am particularly interested in the fact that some nouns are Basic Level words. These seem to have a special status, probably due to their means of acquisition.
5. Many researchers use some variant of a semantic network to represent the lexicon in memory. Basically this model has the lexical entries connected to one another by labeled links or edges. These links identify the kind of relation that exists between the items connected with one another.
6. Answers are derived by traversing the network to find them. Some inferences that may be made are defeasible, which allows for normal or usual inferences to proceed. This works by including the concept of default reasoning which can be overruled by specific information.
7. SnePS a semantic network system developed in Buffalo by S. Shapiro and his colleagues minimizes the kinds of links by making the links themselves accessible to the processor.
8. Some issues:

The lexicon seems to relate to what has been called lexical or conceptual meaning. This gives what is usually called the meaning of the words. When, however, words are used to talk about stuff or to refer to stuff we seem to enter a different ballgame. Certain phrases often refer to things other than themselves, and sentences can be used to make assertions, ask questions, request activities, promise something, create a mood, tell stories, etc. We will not deal with many of these issues in this class, but one aspect of the more global properties of language will be used, either as a metaphor, or directly, for other reasons. Much language is contextually interpreted. That is, it relates to some integrated and (usually) coherent domain, and only makes sense within that domain. Our current term for this domain to which the discourse relates is schema.

Some properties of schemata or issues relating to schema theory