Phonological Priming and Lexical Access in Spoken Word Recognition

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Phonological Priming and Lexical Access in Spoken
Word Recognition
   

• Christine P. Malone
• Minnesota State University Moorhead

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Problems Under Investigation

• How do the processes occurring during early
  stages of spoken word recognition affect
  single-word shadowing (naming) performance?
• How is a string of incoming phonetic features
  mapped onto a remembered lexical item?
• How does phonological information influence the
  organization of lexical items in memory?

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Background on Activation

• During spoken word recognition, listeners
  automatically evaluate the unfolding input by
  activating a set of potential lexical candidates,
  which then compete for recognition.
• The incoming sound pattern determines the
  potential candidates.
• Degree of activation is determined by match
  between the potential candidates and the
  unfolding sensory input.

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Connectionist Models

• Difficulty obtaining facilitation following
  beginning phonological overlap across different
  tasks
• Theoretical interest turned from cohort to
  connectionist theory.
• Multi-level architecture composed of simple
  processing units, called nodes. Adapted from
  visual word recognition.

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Levels of Speech Processing

• Feature Level--Break the speech stream into
  phonetic features, such as voiced/voiceless.
• Phoneme Level--Interpret stream of features and
  produce a prelexical representation.
• Lexical Level--Identify the word.

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A Simplified Connectionist Model(adapted from
Colombo, 1986)
INPUT
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Levels of Speech Processing

• Feature LevelBreak speech into phonetic features
  (e.g., voiced/voiceless)
• Phoneme Level--Interpret stream of features and
  produce a pre-lexical representation.
• Lexical Level--Identify the word.

INPUT
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Priming and the Naming Task

• Shadowing task (naming) involves lexical
  processing, but is relatively unaffected by
  postlexical processing.
• Effect of having recognized the prime on
  recognizing the target?
• Phonological priming--assess differential levels
  of residual activation when manipulating
  phonological overlap and lexicality of prime.

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Experiment 1 Stimuli

• Target motivate
•  
• Match Mismatch
• Early Overlap motorist demote
• Late Overlap innovate atrium
• Unrelated vocalist vocalist

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Hypotheses

• If inhibition takes place among beginning
  phonemes, then Early Overlap/Match targets will
  have longer latencies compared to Late
  Overlap/Match targets.
• If overall match (and not location) is important
  in activation, then Mismatch pairs should show
  same patterns as Match pairs.

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Method

• Auditory priming paradigm, 100 ms ISI
• Single word shadowing (or naming) task, each list
  contained 8 EM, 8 EMM, 8 LM, 8 LMM, and 8
  Unrelated pairs.
• Digitally recorded stimuli (22kHz, 16-bit) using
  SoundEdit and presented via PsyScope.
• Voice-activated reaction times recorded from
  target onset until beginning of vocal response.

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Graph
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Shadowing Latencies
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Conclusions

• Shared beginnings slowed naming of target
  (inhibition) for word and nonword targets.
• Potential candidates are inhibited based on
  matching beginning information, supporting
  connectionist architecture.

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Applications

• Questions regarding the lexicon architecture have
  important implications for how we understand and
  model the word recognition system.
• Empirical data is useful for scientists studying
  language processing, as well as for scientists
  developing speech recognition systems.

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