Computational Models of Speech Production

What are some methods of testing speech production?

Speech errors

Timing of speech onset

Tip of the tongue state

What can we learn from speech errors?

Highlights the processes that are required to plan and execute speech

What is the Model of Utterance Generation? (Fromkin, 1971)

Serial processing (Discrete) -> each stage must be completed before the next can begin

What are the stages of the Model of Utterance Generation? (Fromkin, 1971)

Meaning

Syntactic Structure

Position of intonation

Lexicon look up

Morphonemic contraints

What are some models of speech production?

Dell (1986) and Levelt et al's model (1999)

What are two different types of models?

Box & Arrow + Computational Models

What are nodes in neural networks?

Groups of neurons

What is a summary of Dell's (1986) model of spreading activation?

Semantic and phoneme levels all active at once

What are some predictions of Dell's (1986) model?

Spreading activation results in activation of related items at all levels of processing

Processing items that overlap in semantics and/or phonology will result in higher error rates than processing items that do not overlap

What is some evidence behind Dell's (1986) model?

Semantic and phonological similarity can result in speech errors suggesting that processing is fluid and interactive

What is a blend error?

Both concepts become active resulting in a cascade of processing to the level of phonology

What is a summary of Levelt et al's (1999) model?

Word-form Encoding by Activation and VERification

What does the term discrete mean in the WEAVER++ model? Levelt et al (1999)

Activation is 'feed forward' can only move from meaning to sound (one way)

What is LEMMA?

The word form and the syntactic information that links with the word form

What are competitive processes?

Selection of items at each level is based on competition between items

What does Levelt et al's (1999) model predict?

Items which are semantically similar will inhibit processing

What is some evidence to back up the WEAVER++ model?

Mean Reaction Times (RTs) in milliseconds for Semantically related & unrelated items

Is speech production based on interactive processes?

Evidence that semantically related items inhibit processing of each other suggests that speech production processes are discrete

What about Speech Errors in Levelt et al.'s WEAVER ++ model?

Errors may occur if the wrong concept is selected and processed to the phonological level

Is processing interactive or discrete?

According to Levelt et al. phonological similarity should not affect processing of competing items- this is disputed