Introduction

Canonical bias vs. variant equivalence

• Carefully-articulated words in canonical forms fare better in word recognition (e.g., Pitt, 2009; Tucker and Warner, 2011)

• Multiple pronunciations of a word with different variants (e.g., [nt] vs [n_] for "center") fare equally well (e.g., Sumner and Samuel, 2005) 
  • no difference in canonical vs. non-canonical forms

Canonical bias vs. variant equivalence (cont.)

• Explaining the canonical bias
  • prominence of the (infrequent, but) idealized word form
  • [variant equivalence] depends on the [following] phonological context
    • the context for variants has to be present
    • [wɪkɪb] (variant for "wicked") only triggers lexical access preceding a labial-initial word (Gaskell and Marslen-Wilson, 1996)
    • a word like "tas" can trigger "tast" when the following word provides a context for t-deletion (Mitterer and McQueen, 2009)

• Explaining the variant equivalence
  • the co-present phonetic and/or allophonic properties in natural speech

Reconciling the two opposing views

• Cannot be simply explained by frequency effect

• Possibility: Variants may be linked with how a word is pronounced (phonetic composition/context)

• E.g., post-nasal [t] deletion is less likely when the following syllable is more prominent

• Hypothesis: in careful speech, the reduced form has disadvantage

Experiment 1

Participants and Stimuli

• Participants: 60 undergraduates, monolinguals of AE

• Stimuli:

  • 48 critical primes with medial /nt/

  • 144 filler primes and targets

    • 48 real-real pairs, 96 pseudo-real pairs

  • all words were pronounced in three conditions:

    • careful [nt], careful [n], casual [n]

Design and Procedure

• Within-subject, blocked by condition

• One trial:

  • auditory prime -> 100 ISI -> visual target -> response

  • next trial: 1000 ms after a response, or 3000 ms

• Lexical decision on the target

Hypotheses and Predictions

• If canonical bias is independent of phonetic context

  • careful [nt] > careful [n_] and casual [n_]

• If word-level phonetic context drives the difference

  • careful [nt] and casual [n_] > careful [n_]

Results

• Significant relatedness x prime condition interaction
  • careful [n_] condition has worse priming effect (slower than careful [nt] and casual [n_] condition when words are related)

Discussion

• Replicating the results of previous findings:
  • Priming effects are strong for carefully articulated canonical variants
  • No priming effect for carefully articulated non-canonical variants

• New finding:
  • Casual non-canonical form is just as robust in priming condition

Experiment 2

Participants and Stimuli

• Participants: 48 native AE speakers

  • three groups (between-subject design)

• Critical primes remain the same as in exp1

  • careful [nt], careful [n_], casual [n_]

  • target: [nn] pseudowords (e.g., splinner)

Design (quite complex...)

• Each condition has two lists 
• Each list has two blocks:
  • Block 1 (auditory primes and fillers):
    • 24 primes (careful splinter or casual/careful splinner )
    • 24 pseudoword fillers
    • 36 real word filler
  • Block 2 (visual targets and fillers):
    • 48 targets
      • 24 targets: "splinner"
      • 24 "new"
    • 48 pseudo word fillers (half old, half new)
    • 72 real word fillers (half old, half new)

Task/Procedure

• Task:
  • block 1 (primes): pressed a button at item completion
  • block 2 (targets): lexical decision
    • Analysis depends on Block 2
    • To see "Whether the prime inhibits the ability to reject the target pseudowords"

• Why not direct priming?
  • There may be effects of form-based, not lexical, activation with direct lexical decision on the p
  • Analysis on block 2 avoided explicit decisions about word form

Results

• Significant prime condition x target type interaction
  • careful [n_] primes shows no inhibition effect (not slower) for primed targets

Discussion (cont.)

• The bias toward canonical variants is not due to an idealized lexical representation.
  • careful [nt] = casual [n_]

• A reduced, surface-based variant is not costly to spoken word recognition.
  • careful [nt] = casual [n_]

Discussion

• The recognition of variant words depends heavily on the phonetic composition of the entire word.
  • careful [n_] vs. casual [n_]

• Variants experienced with different frequencies result in similar patterns
  • careful [nt] = casual [n_]

• Carefully reduced variants do not get into long-term memory even when it resembles the target

Discussion and Conclusion

Explaining canonical bias vs. variant equivalence

• Differences between processing careful and casual speech
  • Careful speech, processed better with clear signal
    • The difference between careful [nt] vs careful [n_]
    • No enough phonetic residual to cue absent sounds
      • i.e., the context for reduced variants is not there
  • Casual speech, noisy signal, top-town processing
    • Careful [nt] worked as well as casual [n_]
  • This account avoids the problem of frequency-based explanation

• Conclusion

• Multiple pronunciation variants are recognized equally well in a congruent phonetic word frame.

• Canonical bias may partially be bolstered by "comparisons", not by an idealized representation.
  • using a process-base account to explain the long-term memory benefits for perceived standard forms.

• Thoughts

• No casual [nt]
  • Maybe [nt] will always win regardless of the phonetic context

• Express letters
  • difficult to read
  • who's the audience?