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

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?

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.

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

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.

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

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. WORD FEATURE LETTER INPUT

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.

Experiment 1 Stimuli Target: motivate MatchMismatch Early Overlapmotoristdemote Late Overlapinnovateatrium Unrelatedvocalistvocalist

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.

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.

Graph

Shadowing Latencies

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.

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.