Production and Comprehension of Time Reference in Korean Nonfluent Aphasia.
OBJECTIVE
Individuals with nonfluent agrammatic aphasia show impaired production and comprehension of time reference via verbal morphology. However, cross-linguistic findings to date suggest inconsistent evidence as to whether tense processing in general is impaired or time reference to the past is selectively difficult in this population. This study examined production and comprehension of time reference via verb morphology in Korean-speaking individuals with nonfluent aphasia.


METHODS
A group of 9 healthy controls and 8 individuals with nonfluent aphasia (5 for the production task) participated in the study. Sentence priming production and auditory sentence to picture matching tasks were used, parallel with the previous cross-linguistic experiments in English, Chinese, Turkish, and others.


RESULTS
The participants with nonfluent aphasia showed different patterns of impairment in production and comprehension. In production, they were impaired in all time references with errors being dominated by substitution of incorrect time references and other morpho-phonologically well-formed errors, indicating a largely intact morphological affixation process. In comprehension, they showed selective impairment of the past, consistent with the cross-linguistic evidence from English, Chinese, Turkish, and others.


CONCLUSIONS
The findings suggest that interpretation of past time reference poses particular difficulty in nonfluent aphasia irrespective of typological characteristics of languages; however, in production, language-specific morpho-semantic functions of verbal morphology may play a significant role in selective breakdowns of time reference.
Aphasia & Neurolinguistics Research Laboratory, Communication Sciences and Disorders, Northwestern University, Evanston, IL, USA ; Department of Speech, Language, and Hearing Sciences, Purdue University, West Lafayette, IN, USA.
Jiyeon
J
Lee
Department of Neurology, Asan Medical Center, University of Ulsan College of Medicine, Seoul, Korea.
Miseon
M
Kwon
Department of Neurology, Bobath Memorial Hospital, Seongnam, Korea.
Hae Ri
HR
Na
Center for Language and Cognition Groningen, University of Groningen, Groningen, The Netherlands.
Roelien
R
Bastiaanse
Aphasia & Neurolinguistics Research Laboratory, Communication Sciences and Disorders, Northwestern University, Evanston, IL, USA.
Cynthia K
CK
Thompson
Aphasia; Korean language; Tense; Time reference; Verb inflection