Phonological Priming and Lexical Access in Spoken Word Recognition

1. Phonological Priming and Lexical Access in Spoken Word Recognition Christine P. Malone Minnesota State University Moorhead

2. 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?

3. 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.

4. 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.

5. 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.

6. WORD LETTER FEATURE A Simplified Connectionist Model(adapted from Colombo, 1986) INPUT

7. WORD LETTER FEATURE Levels of Speech Processing • Feature Level—Break 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

8. 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.

9. Experiment 1 Stimuli Target: motivate Match Mismatch Early Overlapmotorist demote Late Overlapinnovateatrium Unrelated vocalist vocalist

10. 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.

11. 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.

12. Graph

13. Shadowing Latencies

14. 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.

15. 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.