Do morphophonological rules impact both regular and irregular verb inflection? Evidence from acquired morphological impairment
-
1
New York University, United States
Introduction
The role of morphophonological rules in production is a frequent point of contention in competing theories of morphological processing. Dual-mechanism theories have posited that a single default rule (stem+ed) is used to produce the regular past tense, while all other past-tense forms are memorized and retrieved whole. However, research has suggested that a series of stochastic morphophonological rules plays a role in morphological productivity for both regular and irregular novel verbs (e.g. Albright & Hayes, 2003). Under this view, the likelihood of a given rule applying to a verb is partially dependent on its lexical support, measured as the number of phonologically similar verbs in the lexicon which take the same inflectional change (e.g. weep→wept, sweep→swept, etc.). To date, most evidence supporting this view has come from the morphological productivity of novel forms (e.g. Albright & Hayes, 2003) and from visual word recognition (Fruchter, Stockall, & Marantz, 2013). The present study extends this work by demonstrating that morphophonological rules impact production more generally, including the production of both regular and irregular past tense in RMI, an aphasic individual with an established morphological deficit (Rimikis & Buchwald, 2014).
While we previously reported differences in production for irregular verbs with either high or low levels of lexical support, the current study further examined this phenomenon, and we found that the production of the past-tense form for both regular and irregular verbs was affected by the support for that verb’s inflectional rule .
Subject
RMI, 39, right-handed male with aphasia secondary to L-MCA CVA. His production includes frequent morphological errors across tasks, with semantic and phonological errors also occurring.
Procedure
RMI was administered a past-tense elicitation task. Sentence frames including regular and irregular verbs were presented verbally and visually (e.g. “Every day I run a mile. Just like every day, yesterday I ____ a mile”; N=800).
Analyses
A confidence score was calculated for each verb, representing the amount of lexical support for its inflectional pattern based on morphophonological rules (Albright & Hayes, 2003). Logistic-regression mixed-effects models were used to assess the impact of this confidence score on RMI’s production above that of other lexical variables. Accuracy and error patterns were analyzed separately for regular and irregular verbs.
Results
Confidence score was a significant predictor of performance for both regular and irregular verbs. For regular verbs, words with higher confidence scores were more likely to be produced accurately (see Figure 1). For irregular verbs, words with lower confidence scores were more likely to be regularized (i.e. affixation of –ed, e.g. "digged").
Discussion
For irregular verbs, lexical support for the particular morphophonological rule affected error type, with words with less support being more likely to regularize. Interestingly, our findings indicate that even regular verbs are sensitive to lexical support as words with less support for the regular pattern were more vulnerable to error. These findings provide additional evidence that morphophonological rules impact spoken production, and may be problematic for accounts in which a single, default rule is used in production.
References
Albright, A., & Hayes, B. (2003). Rules vs. analogy in English past tenses: A computational/experimental study. Cognition, 90(2), 119-161.
Fruchter, J., Stockall, L., & Marantz, A. (2013). MEG masked priming evidence for form-based decomposition of irregular verbs. Frontiers in human neuroscience, 7.
Rimikis S and Buchwald A (2014). Combinatorial Processing of Irregular Verbs: Evidence from Aphasia. Front. Psychol. Conference Abstract: Academy of Aphasia -- 52nd Annual Meeting. doi: 10.3389/conf.fpsyg.2014.64.00001
Keywords:
morphology,
Aphasia,
irregular verbs,
morphological production,
morphophonological rules
Conference:
Academy of Aphasia 53rd Annual Meeting, Tucson, United States, 18 Oct - 20 Oct, 2015.
Presentation Type:
platform paper
Topic:
Student first author
Citation:
Rimikis
S and
Buchwald
A
(2015). Do morphophonological rules impact both regular and irregular verb inflection? Evidence from acquired morphological impairment.
Front. Psychol.
Conference Abstract:
Academy of Aphasia 53rd Annual Meeting.
doi: 10.3389/conf.fpsyg.2015.65.00028
Copyright:
The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers.
They are made available through the Frontiers publishing platform as a service to conference organizers and presenters.
The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated.
Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed.
For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions.
Received:
01 May 2015;
Published Online:
24 Sep 2015.
*
Correspondence:
Ms. Stacey Rimikis, New York University, New York, NY, United States, stacey.rimikis@nyu.edu