Morphology and Meaning in the English Mental Lexicon

Morphology and Meaning in the English

Mental LexiconBy William Marlsen-Wilson, Lorraine

Komisarjevsky Tyler, Rachelle Waksler, and Lianne Older

Presented by Robyn Maler

Questions

How are lexical entries represented in the mental lexicon?

Are their representations based on whole phonetic words (full listing hypothesis) or morphemes (morphemic hypothesis)?

Are there differences between lexical representations at different levels?

Background

Lexical entry is distinct from access representation

Morphological category: the basic linguistic characteristics of the affixes (derivational vs. inflectional, prefix vs. suffix)

Semantic transparency: whether the form is synchronically compositional

Phonological transparency: whether the form has the same phonetic shape for both its affixed and unaffixed versions

Experimental Task Design

Cross-modal immediate repetition priming: subject hears a multimorphemic spoken word (prime) and immediately after sees a visual probe (target)

Subject must make a lexical-decision response to this probe

Response facilitation (priming) is measured by response latency relative to a baseline condition (subject’s response to same probe following unrelated prime)

Questions for Experiments 1-3:

Is the lexical entry for derived suffixed words in English morphologically structured?

How does the semantic and phonological transparency of stem and affix morphemes affect the representation of a derived form?

Experiment 1

Purpose: to determine whether there is evidence for a level of morphologically structured lexical representation that abstracts away from shared surface phonetic properties

Table 1: Experiment 1Condition Morphologi

cal TypeExample Result

1: [+Morph, +Phon]

Derived-stem Friendly/friend Priming observed

2: [+Morph, -Phon]

Derived-stem Elusive/elude Priming observed

3: [+Morph, -Phon]

Derived-stem Serenity/serene

Priming observed

4: [-Morph, +Phon]

NA Tinsel/tin No priming

Results and Discussion

Results are consistent with hypothesis that derived suffixed forms prime their free stems because of lexical entry processes and not just surface phonetic overlap

Experiment 2

Purpose: to determine whether the priming observed in [+Morph] conditions in Experiment 1 are simply due to semantic relationships between morphologically related pairs instead of shared morphemes in a morphologically structured mental lexicon

Table 2: Experiment 2Condition Morphological

typeExample Result

1: [-Sem, +Morph]

Derived-stem Casualty/casual No significant priming effect

2: [+Sem, +Morph]

Derived-stem Punishment/punish Priming observed

3: [-Sem, +Morph]

Derived-derived Successful/successor No priming

4: [+Sem, +Morph]

Derived-derived Confession/confessor No priming

5: [+Sem, -Morph, -Phon] (CONTROL)

NA Idea/notion Priming observed

6: [-Sem, -Morph, +Phon] (CONTROL)

NA Bulletin/bullet No priming

Results and Discussion

Priming only occurs when there is a synchronically semantically transparent relationship between derived and stem forms

Semantic links alone can produce priming, but semantic relatedness is not the only factor affecting facilitation!

Experiment 3

Purpose #1: to study effects of morphological type and semantic transparency more rigorously

Purpose #2: to investigate a new prime-target combination (stem-derived)

Table 3: Experiment 3

Condition Morphological type

Example Result

1: [-Sem, +Morph]

Derived-stem Casualty/casual No priming

2: [+Sem, +Morph]

Derived-stem Punishment/punish Strong priming observed

3: [-Sem, +Morph]

Derived-derived Successful/successor No priming

4: [+Sem, +Morph]

Derived-derived Confession/confessor No priming

5: [+Sem, +Morph]

Stem-derived Friend/friendly Strong priming observed

Results and Discussion

confirm results of Experiment 2

fit with prediction of shared-morpheme account of [+Sem, +Morph] priming

Experiment 4

Purpose #1: to investigate semantic transparency for prefixing morphology

Purpose #2: investigate morphological type (whether derived-derived and derived-stem prefixed pairs exhibit priming effects)

Table 4: Experiment 4

Condition Morphological type

Example Result

1: [-Sem, +Morph]

Derived-stem Restrain/strain No priming

2: [+Sem, +Morph]

Derived-stem Insincere/sincere Priming observed

3: [-Sem, +Morph]

Derived-derived Depress/express No priming

4: [+Sem, +Morph]

Derived-derived Unfasten/refasten Strong priming observed

Results and Discussion

Like the suffixed pairs, only [+Sem] prefixed pairs showed priming

Prefixed [+Sem] derived-derived pairs show strong priming effects, consistent with idea that they are not cohort competitors

Prefixed [-Sem, +Morph] forms (e.g. mistake) are represented as monomorphemic items WHEREAS prefixed [+Sem, +Morph] forms (e.g. refasten) are broken down into abstract stems and prefixes at the level of lexical entry

Experiment 5

Purpose: to investigate stem-derived order in prefixed pairs

Table 5: Experiment 5Condition Morphological

typeExample Result

1: [-Sem, +Morph]

Stem-derived Strain/restrain No priming

2: [+Sem, +Morph]

Stem-derived Sincere/insincere Priming observed

3: [-Sem, +Morph]

Bound stems Submit/permit No priming

4: [-Morph, +Phon]

Pseudoprefixed Dispatch/patch No priming

5: [-Morph, +Phon]

Initial stress Mildew/dew No priming

6: [-Morph, +Phon]

Final stress Trombone/bone No priming

Results and Discussion

Condition 3 results provide more evidence that there is no facilitation when there is no synchronic semantic basis for representing a word form as morphologically complex

Results consistent with a model of lexical representation in which there are inhibitory links between suffixes but not prefixes that share the same stem

Experiment 6

Purpose: to explore relationship between prefixed and suffixed forms

Table 6: Experiment 6

Condition Morphological type

Example Result

1: [+Sem, +Morph]

Prefix-suffix Distrust/trustful Priming observed

2: [+Sem, +Morph]

Suffix-prefix Judgment/misjudge Priming observed

3: [-Sem, +Morph]

Stem-derived Apart/apartment No priming

Results and Discussion

Consistent with a cohort-based model in which there are inhibitory links between competing suffixed forms but not prefixed and suffixed forms

In summary…Semantically transparent suffixed pairs

prime each other except in the case of two suffixed forms, which demonstrate a cohort-based inhibitory effect

Semantically transparent prefixed pairs always prime each other

Semantically opaque pairs do not prime each other

Thus, semantically transparent forms are decomposed at the level of lexical entry, while semantically opaque forms are represented monomorphemically

…cont’d

Phonological opacity had no effect on results

Thus, morphemes are phonologically abstract

What does it all mean?

Results suggest that there is a modality-independent and morphologically structured lexical level

The basic unit in terms of which the lexicon is organized, at least for derivational forms in English, is the developmentally-defined morpheme

The findings are (kind of) consistent with a partial decomposition view of the lexicon