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1
The Unaccusative Construction in Aphasia
Implications for the Representation of Syntactic
Movement Tara McAllister1,3, Gloria Waters1,
David Caplan2, Asaf Bachrach3 (1) Department of
Health Sciences, Sargent College, Boston
University (2) Neuropsychology Laboratory,
Massachusetts General Hospital (3) Department of
Linguistics and Philosophy, Massachusetts
Institute of Technology
Introduction
Study Design
Results
Conclusion

• Task 1 Single-Word Naming (cf. Thompson 2003)
• Targets were 15 unaccusative and 10 unergative
  verbs, balanced for lexical frequency across
  classes.
• Prediction Patients will name unergative verbs
  with greater accuracy than unaccusative verbs.
• Task 2 Sentence Production (cf. Lee Thompson
  2004)
• Pictures from Task 1 were presented together with
  the bare stem of the target verb in spoken and
  written form.
• Prediction Patients will produce significantly
  fewer errors affecting argument structure in
  unergative sentences.
• Task 3 Auditory Sentence-Picture Matching
• Subjects chose one of two pictures to match a
  spoken sentence. As a baseline for movement
  effects, simple transitive verbs were presented
  in active and passive conditions. Alternating
  unaccusative verbs were presented in transitive
  and intransitive conditions.

• Accuracy data were analyzed using a
  repeated-measures ANOVA with the factors of Group
  and Verb Type (Tasks 1 and 2) or Group, Verb
  Type, and Movement Condition (Task 3).
• The difference in accuracy between controls and
  patients reached significance in only one task.
• Reaction time data, collected for Task 3 only,
  revealed that patients responded significantly
  more slowly than controls.

• As predicted, unaccusative verbs were associated
  with decreased performance across production and
  comprehension tasks. Unexpectedly, though, this
  pattern was observed in age-matched controls as
  well as patients with aphasia, with no
  interaction of group and verb type.
• The results of this experiment did not point to
  an aphasia-specific deficit in the representation
  of movement chains.
• Instead, these results supported the hypothesis
  that deficits in aphasic comprehension and
  production are at least in part a reflection of
  reduced processing capacity.
• However, these findings are not incompatible with
  the claim of a representational deficit affecting
  movement in aphasia.
• A single case study (BD) suggested that
  structure-specific movement deficits may be
  characteristic of a subset of individuals with
  aphasia.
• Patients tested here mostly had mild, fluent
  aphasia, while claims about movement deficits are
  frequently specific to agrammatic aphasia.
  Further investigation with a more targeted sample
  of the aphasic population is indicated.

Recent studies have reported impairment in
agrammatic aphasic production of unaccusative
verbs, which contain a passive-like chain of
movement. A theory that links comprehension
deficits in aphasia to representation of movement
chains would also predict a deficit in
comprehension of unaccusatives. We tested the
hypothesis that aphasic patients have specific
deficits affecting movement-related structures by
examining the production and comprehension of
unaccusative and non-movement stimuli in nine
adults with aphasia and matched controls.
Accuracy
Unaccusatives in Aphasia

• The Unaccusative Hypothesis (Perlmutter, 1978)
• Intransitive verbs fall into two classes based on
  the thematic role assigned to the subject.
• Subject Agent Unergative.
• Subject Theme Unaccusative.
• Unaccusative verbs (e.g. fall, bounce, die)
  involve a chain of object-to-subject movement, as
  observed in the passive.
• Evidence from the resultative construction
• Unaccusative The riveri froze ti solid.
• Unergative The boyi laughed (himselfi) silly.
• Several studies have described unaccusative
  production deficits in agrammatic aphasia.
• Thompson (2003), Lee Thompson (2004)
  Unaccusative verbs are produced less accurately
  than frequency-matched unergative verbs in
  picture-naming and sentence production tasks.
• Bastiaanse van Zonneveld (2005) In sentence
  production, unaccusative verbs of alternating
  transitivity are produced more accurately in the
  transitive (non-movement) frame.
• A comprehension deficit has not been documented,
  but existing studies are limited.
• Do these findings point to a representational
  deficit affecting movement constructions?
• If so, affected individuals should show an
  unaccusative deficit across tasks and modalities
  non-aphasic individuals should not.
• Goals of this study
• (1) Devise a more sensitive test for
  comprehension of unaccusatives.

Reaction Time
References

• Bastiaanse, R., van Zonneveld, R. (2005).
  Sentence production with verbs of alternating
  transitivity in agrammatic Brocas aphasia.
  Journal of Neurolinguistics, 18, 57-66.
• Caplan, D., Waters, G., DeDe, G., Michaud, J.,
  Reddy, A. (2007). A Study of Syntactic Processing
  in Aphasia I Behavioral (psycholinguistic)
  aspects. Brain and Language, 101, 103-50.
• Lee, M., Thompson, C. (2004). Agrammatic
  aphasic production and comprehension of
  unaccusative verbs in sentence contexts. Journal
  of Neurolinguistics, 17, 315-330.
• Perlmutter, D. (1978). Impersonal Passives and
  the Unaccusative Hypothesis. In Papers from the
  Fifth Annual Meeting of the Berkeley Linguistics
  Society (pp. 157-189). University of California,
  Berkeley Berkeley Linguistic Society.
• Thompson, C. (2003). Unaccusative verb production
  in agrammatic aphasia The argument structure
  complexity hypothesis. Journal of
  Neurolinguistics ,16, 151-167.
• This research was supported by NIDCD grant DC
  00942 to David Caplan.

Methods

• 9 subjects with aphasia (5 males)
• Mean age 62 years
• Mean years of education 16
• Inclusionary criteria were history of CVA,
  diagnosis of aphasia, and native English speaker
  status.
• Subjects were not included or excluded based on
  aphasic syndrome, lesion location, or severity.
• Subjects tested exhibited relatively mild, fluent
  aphasia. No subject fit the profile of
  agrammatism in production.
• 12 age- and education-matched controls (5 males)