lecture 5 - speech production

Question 1

tongue twisters are tricky because:

Answer 1

rapid sequence of overlapping neural patterns

Question 2

strategies for fluent speech (to reduce processing demands while planning what to say):

Answer 2

1) preformulation = producing phrases used before (accounts for 70% of speech)
2) underspecification = full meaning not explicit e.g. ‘something, ‘things’, ‘them’
3) repetition

Question 3

spreading activation theory (Dell): 4 levels to speech production

Answer 3

1) semantic level = planning level
2) syntactic level = grammatical structure of words (planning)
3) morphological level = morphemes (basic units of meaning)
4) phonological level = phonemes (basic units of sound)
SSMP

Question 4

mild cog impairment - how to monitor disease progression

Answer 4

monitor reduction in semantic content

Question 5

how can we account for mixed findings?

Answer 5

flexibility: speakers are flexible and depends on their immediate goals and situational demands

Question 6

spoonerisms

Answer 6

when initial letters if 2 words are switched - phoneme exchange error

Question 7

Freudian slips

Answer 7

speech errors products of unconscious/repressed thoughts
limitation: where Freud stressed intrusion of thoughts from outside language system, research suggests most errors reflect inner workings of language system

Question 8

semantic substitution errors

Answer 8

when correct word is replaced by word of similar meaning - suggests we plan grammatical structure (syntactic level) before finding precise words to fit that structure

Question 9

morpheme exchange errors

Answer 9

inflections or suffixes remaining in place but attached to wrong words (e.g. I randomed some samply’) - word stems seem to be planned before inflections are added (so processed separately - inflections/suffixes are altered to fit with new word stems)

Question 10

number-agreement errors

Answer 10

singular verbs are mistakenly used with plural subjects & vice versa (e.g. the government ‘have’ made a mess, instead of ‘has)

Question 11

cause of errors

Answer 11

misapplications for combining one type of unit with another - misapplication occurs within a given level (so similar units exchanged)

Question 12

speech errors demonstrate that an utterance is planned

Answer 12

Support for this idea comes from anticipation errors: a particular unit (e.g., a phoneme) is activated as the utterance is being planned, but is produced too early
e.g. “leading list” - the phoneme “l” is produced earlier than intended (and competes with and ultimately replaces the “r”)

Question 13

speech dysfluencies examples

Answer 13

breaks and irregularities within the flow e.g. false starts, restarted/repeated phrases, repeated syllables, fillers ‘uh’, ‘well’, repaired utterances (correcting their slips)

Question 14

error detection: Perceptual loop theory (Levelt)

Answer 14

speakers detect own errors by listening to themselves and discovering what they said differed from what they intended (same when detecting others’ speech with their comprehension system)
error detection is slow

Question 15

error detection: Conflict-based theoretical account (Nozari)

Answer 15

error detection relies on info generated by the speech-production system - conflict monitoring during competition among possible words at time of response
error detection is faster: monitor inner speech

Question 16

evidence is more supportive of detecting errors by conflict monitoring:

Answer 16

1) success of brain-damaged patients in detecting own speech errors depends more on their speech-production ability than their comprehension ability

Question 17

limitations of research in this area:

Answer 17

1) hard to carry out systematic research when occurrence of speech erros and corrections are unpredictable
2) processes involved occur rapidly

Question 18

theories of speech production:

Levelt’s theoretical approach & WEAVER (1989)

Answer 18

computational model: WEAVER++ (Word-form Encoding by Activation & VERification)
focuses on processes involved in producing individual spoken words

Question 19

WEAVER assumptions: 3 main levels

Answer 19

1) feed-forward activation-spreading network - from meaning to sound (highest-lowest)
2) 3 levels:
highest level = nodes representing lexical concepts
second level = nodes representing lemmas (abstract words) from the mental lexicon (word representations specified syntactically & semantically but phonologicaly)
lowest level = nodes representing morphemes & their phonemic (sound-based) segments

speech errors are avoided by monitoring speech

Question 20

lexical selection depends on (WEAVER):

Answer 20

competitve process based on number of lexical units activated - lemma is selected when it is activated more than others

Question 21

morphological encoding & phonological encoding (WEAVER)

Answer 21

1) basic word form of selected lemma is activated
2) word’s syllables are computed
therefore lexicalisation happens = we turn thoughts underlying words into sounds
processing is discrete (separate)

Question 22

Parallel activation will lead to ________ errors

Answer 22

anticipation errors (i.e. word exchange errors and spoonerisms)

Question 23

we can see distinction between lemma and word in the tip-of-the-tongue state

Answer 23

occurs when semantic processing is successful but phonological processing is not
(lemma has been activated but the word form (lexeme) cannot be accessed)
have a concept in mind but can’t find the word

Question 24

Weaknesses of WEAVER

Answer 24

cannot account for the finding that info about the sounds of words also influence which words speakers produce or that semantic word substitutions involve words that are more phonologically similar than is expected by chance

Question 25

Advanatge of model

Answer 25

1) can predict speed of word production

2) focuses on error-free speech - makes sense

Question 26

Ferreira & Griffin (2003)

Answer 26

incomplete sentences shown followed by unrelated pic
had to name the pic (not complete the sentence)
primed sentence completions that were semantically related to pic were substituted for picture names more often than unrelated completions (e.g. nun for priest)
primed sentence completions that were homopones of semantic competitors also substituted for pic names (e.g. none for priest)
- shows that semantic AND phonological info can jointly influence lexical selection (supports interactive theories)

Question 27

spreading activation model (Dell)

Answer 27

nodes (correspond to words or concepts) vary in activation
when a node/word is activated, activation spreads to to other related nodes
can also account for sounds

Question 28

spreading activation model: 4 levels

Answer 28

speech planning happens at same time at all 4 levels
1) semantic level = meaning/abstract representation
2) syntactic level = grammatical structure of words
3) morphological level = morphemes
4) phonological level = phonemes (pronunication info)
SSMP
categorical rules at each level
a lexicon in the form of a connectionist network - nodes for words, morphemes and phonemes

Question 29

insertion rules (spreading activation model):

Answer 29

1) most activated node belonging to most appropriate category is chosen
2) after selection, its activation level reduces to zero - prevents it from being selected repeatedly

Question 30

weaknesses of spreading activation model

Answer 30

1) focuses on indvidual words
2) focused on errors
3) can’t say much about time take to produce words

Question 31

advantages of spreading activation model

Answer 31

1) predicts nature and number of speech errors