Ling 580E Lexical Ambiguity

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Ling 580ELexical Ambiguity

• Forster Hector 2002

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Salient Nuggets

• Semantic features active early in the lexical
  processing cycle
• Form features active early as well
• Dense orthographic neighborhoods for non-words
  have an inhibitory effect on lexical decision
  (less clear for words)?
• Within orthographic neighborhoods, semantic
  features of neighbors can affect a modified
  lexical decision task

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Experiments

• Task Is the letter string an animal?
• Question Do high-N nonwords take longer to
  classify than others?
• Question Do the semantic features of neighbors
  have an effect?

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Experiment 1

• Is the letter string an animal?
• Experiment 1 materials (differing Ns)
• bear ramen ramin
• bees valley walley
• eagle polar poler
• turtle
• Results no effect of N
• Problem Lit suggests a intrinsic form-first
  effect for non-words, irrespective of task

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Experiment 2

• Is the letter string an animal?
• Experiment 2 materials (differing Ns)
• whale ramen ramin whele
• lizard valley walley bizard
• eagle polar poler eigle
• turtle turple
• Results nonwords with an animal neighbor did
  have an effect, but nonwords with nonexamplar
  neighbor (e.g., cishop) had no effect

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Experiment 2

• Suggests Semantic properties of individual
  neighbors are taken into account prior to
  decision
• But, semantically irrelevant candidates do not
  slow the decision process
• Thus, semantic context animal or not affects
  RT depending on the semantic features of
  orthographically similar neighbors

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Experiment 3

• Is the letter string a word? (lex. decision)
• Experiment 3 materials

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Experiment 3

• Experiment 3 results

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Experiment 4

• Is the letter string an animal?
• Experiment 4 materials

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Experiment 4

• Results high non-N nonwords with an animal
  neighbor did not take longer to reject than low-N
  nonwords with an animal neighbor
• In other words, animal neighbor was the most
  important variable
• ..what appears to be happening is that the
  presence of a single animal neighbor does indeed
  delay any decision...but only one word needs to
  be checked. The other neighbors are ignored.

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General Info

• Some models (e.g., links model) predict form
  processing before semantic processing
  therefore, orthographic neighbors should have an
  effect irrespective of task (e.g., semantic,
  lexical decision, etc.)
• Some models (e.g. cascaded semantic-first)
  predict salient semantic features will affect
  task, but form will not (e.g., no non-word N
  effect in semantic task)

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General info

• Experiments 1,2,4 show that semantic effects are
  important non-words with animal neighbors
  faster than others in a semantic categorization
  task
• Experiment 3, however, shows the form is also
  important non-words with no neighbors much
  faster in lexical decision
• What the results dont tell us how early are
  the semantic effects

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Relevance

• Semantic context relevant