Stem Homograph Inhibition and Stem Allomorphy: Stem Homograph Inhibition and Stem Allomorphy: RepresentingRepresenting

and Processing Inflected Forms in a Multilevel Lexical and Processing Inflected Forms in a Multilevel Lexical System, 1999System, 1999

&&Morphological Parsing and the Perception of Lexical Morphological Parsing and the Perception of Lexical

Identity:Identity:A Masked Priming Study of Stem Homographs, 2002A Masked Priming Study of Stem Homographs, 2002

William Badecker and Mark AllenWilliam Badecker and Mark Allen

Presented by Nataliya ChabanyukPresented by Nataliya Chabanyuk

Instructor Nina KazaninaInstructor Nina Kazanina

PsycholinguisticsPsycholinguistics

Research questionResearch question

Two views are opposed:Decompositional, parsing: (novel words as unboyfriendable )

VSWhole word based access(frequent morphological complex

words )

Any preference? Should the both work?

Research questionResearch question

When and where decompositional processes come into play in the comprehension system:

Only for learning?Or, also

For recognition and comprehension?

BackgroundBackground Evidences that morphological structure plays a role in the processing of complex

words are compatible with both

whole-word and decompositionalwhole-word and decompositional models of representation.

• Inhibitory priming between stem homographs in Italian:

• colp-a colp-o ‘guilt’/’blow’• coll-o/pont-e colp-o ‘neck/bridge’

BackgroundBackground

Interpretation:Interpretation: inhibition reflects a competetive realtionship between stem representations rather than whole-word representations in the mental lexicon.

BUTBUTPerhaps the orthographic similarity alone

can account for the inhibition that is observed in the stem homograph condition?

TerminologyTerminology

Processing/representational level:lemma VS lexeme

Lexeme:Lexeme: form based lexical representationLemma:Lemma: modality-neutral lexical

represenation

Lexemes goes & went have one lemme in common,

probably go.

Experiment 1 & 2, 1999Experiment 1 & 2, 1999To take stem homograph inhibition

as evidence for morphological decomposition,it must be shown that the inhibition derives

from stem-level competition and not justfrom word-level orthographic competition.

Ex.2 shows that words that areorthographically related in the same way that

stem homographs are will not inhibiteach other in the same way or to the same

degree that stem homographs do.

Experiment 1 & 2, 1999Experiment 1 & 2, 1999• Stem homograph: MOR-IA• Orthographic relative: MORAL• Stem homograph• allomorph: MUER-E MOR-OS• Orthographic related: MIR-AN• Unrelated control: SILL-A

Recognition of the plural noun mor-os (Moors) should be slowed not just by the verb form mor-ia(die, 1st/3rd person sing. Imperfect), but also by an allomorph of this form, muer-e(die, 3rd person sing, present)

Experiment 1 & 2, 1999Experiment 1 & 2, 1999

Participants: native speakers of Spanish

Procedure: Fixation cross for 400 ms50 ms after:Prime for 250 msImmediately after:Target and remained present until the participant made a response

Experiment 1, 1999

Experiment 2, 1999

DiscussionDiscussion

Competition may arise at another level within the lexical processing system:

specifically, at a level of representation where all the members of an inflectional paradigm share a single (abstract) morphological entry. (M-level).

• Results go AGAINSTAGAINST the hypothesis that the stem homoghraph effect can be reduced to an orthographic phenomena.

Ex.1, 2002Ex.1, 2002

Masked prime with subject awareness control

Partcipants: Spanish nativeProcedure: ££££££££££££ for 500 msMasked prime for 67 ms: 4 screen refresh

ticks at 16.67 msTarget for 500 msLexical desicion taskITI 1500 ms

Ex.1, 1999 & Ex. 1, 2002Ex.1, 1999 & Ex. 1, 2002

To contrast masked masked stem homograph primes with unmaskedunmasked stem homograph primes in the frame of the paersing model of inflectional processing.

Prediction:Prediction: Facilitative effect of masked stem

homographs primes AGAINSTAGAINST

Inhibition effect of unmasked stem homograph prime

Unmasked prime from Ex.1, 1999

Masked prime from Ex.1, 2002

DiscussionDiscussionStem homographs are not not just whole-word

orthographic neibours.The facilitation indicates that ambiguousstems activate multiple affiliated lemmas

prior to recognition. On the decomposition

plus selection model we find facilitation, ratherthan inhibition or no effect, because suppression

occurs only when lexical selection inducesthe conscious perception of a word as a particular

word.

Ex.2 & ex. 3, 2002Ex.2 & ex. 3, 2002To test hard-wired model against

the parsing model:

InhibitionInhibition for masked stem homograph allomorph in former case AGAINSTAGAINST nul-

effect in the latter case. cierr-a cerr-o close/hill To rule outrule out other potential reasons for the

expected null effect: e.g. semantics and to verify the masked prime facilitates other members of their inflectionalm cohort

cierr-a cerr-ar

Experiment 2, 2002

Experiment 3, 2002

Ex. 4, 2002Ex. 4, 2002

• To ensure that a masked stem homograph facilitates an allomorphic memebr of its competitor lemma’s paradigm and not just lexeme level entries that correspond to the exact orthographic form of the prime’s stem.

• cerr-o cierr-a• So, if masked RevSHA priming is

facilitative, then we will have evidence that masked SH facilitaiton derives from facilitaiton derives from lemma-level sourceslemma-level sources.

Experiment 3, 2002

Experiment 4, 2002

Experiment 1, 2002

Experiment 4, 2002

DiscussionDiscussionLexical processing does notdoes not operate exclusivelyin terms of whole-wordterms of whole-word recognition procedures

For familiar words with ambiguous morphological constituents.

Even if the access systemhas supplementary whole-wordsupplementary whole-word procedures

for familiar targets, the facilitation and inhibitionobserved, respectively, in masked and

unmasked stem-homograph priming indicatesthat the decomposition approachdecomposition approach still contributes

to the recognition process for these forms.

ConclusionConclusion Obligatory decompositionObligatory decomposition of complex words may be favored

regardless of whole-word familiarity because it offers a way to extract the

morpho-syntacticand conceptual information that is encoded

separately in affixes and stems.

Timing makes difference!Timing makes difference!