Interpreting Mini-Mental State Examination Performance in Highly Proficient Bilingual Spanish-English and Asian Indian-English Speakers: Demographic Adjustments, Item Analyses, and Supplemental Measures.

Purpose: Performance on the Mini-Mental State Examination (MMSE), among the most widely used global screens of adult cognitive status, is affected by demographic variables including age, education, and ethnicity. This study extends prior research by examining the specific effects of bilingualism on MMSE performance. Method: Sixty independent community-dwelling monolingual and bilingual adults were recruited from eastern and western regions of the United States in this cross-sectional group study. Independent sample t tests were used to compare 2 bilingual groups (Spanish-English and Asian Indian-English) with matched monolingual speakers on the MMSE, demographically adjusted MMSE scores, MMSE item scores, and a nonverbal cognitive measure. Regression analyses were also performed to determine whether language proficiency predicted MMSE performance in both groups of bilingual speakers. Results: Group differences were evident on the MMSE, on demographically adjusted MMSE scores, and on a small subset of individual MMSE items. Scores on a standardized screen of language proficiency predicted a significant proportion of the variance in the MMSE scores of both bilingual groups. Conclusions: Bilingual speakers demonstrated distinct performance profiles on the MMSE. Results suggest that supplementing the MMSE with a language screen, administering a nonverbal measure, and/or evaluating item-based patterns of performance may assist with test interpretation for this population.

Agrammatism in Jordanian-Arabic speakers.

The studies of agrammatism show that not all morpho-syntactic elements are impaired to the same degree and that some of this variation may be due to language-specific differences. This study investigated the production of morpho-syntactic elements in 15 Jordanian-Arabic (JA) speaking individuals with agrammatism and 15 age-matched neurologically healthy individuals. Two experiments were conducted to examine the production of complementizer, tense, agreement and negation morphology in JA. The results indicated that the speakers of JA with agrammatism had marked dissociations in producing specific morpho-syntactic elements. The observed impairment patterns overlapped, in many respects, with those observed in other linguistic groups. The findings are discussed with respect to current theories of agrammatism, including both morpho-syntactic and computational accounts.

Functional category production in English agrammatism.

BACKGROUND: Individuals with agrammatism show selective deficits in functional categories. The Tree Pruning Hypothesis (TPH; Friedmann & Grodzinsky, 1997) suggests that this results from inability to project certain nodes in the syntactic tree. On this account, higher nodes in the tree are more vulnerable than lower ones. Other theories, however, suggest that functional category impairments can be explained in the context of a morphological deficit (e.g., Arabatzi & Edwards, 2002; Penke, 2003; Thompson, Fix, Gitelman, 2002). AIMS: This study examined production of complementizers, tense, and agreement morphology in four English-speaking agrammatic participants to test the hierarchical nature of functional category deficits. The consistency of verb inflection errors was also tested under conditions examining a minimal set versus a full array of English inflected forms. MATERIALS #ENTITYSTARTX00026; PROCEDURES: In experiment 1, participants were asked to produce sentences by using a complementizer (i.e. whether, that, and if), a tense (-ed) or agreement marker (-s), in structured sentence elicitation tasks. In experiment 2, the participants' production of both finite and nonfinite verb inflection forms was examined. OUTCOME #ENTITYSTARTX00026; RESULTS: All participants produced complex sentences successfully using a complementizer, indicating intact projection to the Complementizer Phrase (CP). As for tense and agreement (structures within the Inflection Phrase (IP)), the agrammatic speakers were impaired in both categories and they showed higher scores in nonfinite vs. finite verb conditions. Further, their errors were dominated by substitutions, rather than omissions, with various non-target morphemes. CONCLUSIONS: Our agrammatic participants' deficits are morphological, rather than syntactic. The participants were able to project to the upper most structure, CP. They showed the ability to project verb inflection and to implement inflectional rules in their grammar. However, instantiation of grammatical markers sometimes failed to operate, resulting in incorrect inflectional forms. These findings suggest that within the domain of functional categories, IP- and CP-level deficits may result from disruption of differing underlying mechanisms and, therefore, they may require separate treatment strategies.

Judgment of functional morphology in agrammatic aphasia.

Individuals with agrammatic Broca's aphasia show deficits in production of functional morphemes like complementizers (e.g., that and if) and tense and agreement markers (e.g., -ed and -s), with complementizers often being more impaired than verbal morphology. However, there has been comparatively little work examining patients' ability to comprehend or judge the grammaticality of these morphemes. This paper investigates comprehension of complementizers and verb inflections in two timed grammaticality-judgment experiments. In Experiment 1, participants with agrammatic Broca's aphasia and grammatical-morphology production deficits (n=10) and unimpaired controls (n=10) heard complement clause sentences, subject relative clause sentences, and conjoined sentences. In Experiment 2, the same participants heard sentences with finite auxiliaries, sentences with finite main verbs, and sentences with uninflected verbs. Results showed above-chance accuracy in aphasic participants' judgments for complementizer sentences in Experiment 1, but chance performance for verb inflections in Experiment 2. This pattern held regardless of whether the verb inflections were affixes or free-standing auxiliaries. Implications of these results for theories of agrammatic morphological impairments, including feature underspecification accounts (Wenzlaff & Clahsen, 2004; Burchert, Swoboda-Moll & DeBleser, 2005a) and hierarchical structure-based accounts (Friedmann & Grodzinsky, 1997; Izvorski & Ullman, 1999), are discussed.

A psychometric analysis of functional category production in English agrammatic narratives.

Hierarchical models of agrammatism propose that sentence production deficits can be accounted for in terms of clausal syntactic structure [Friedmann, N., & Grodzinsky, Y. (1997). Tense and agreement in agrammatic production: Pruning the syntactic tree. Brain and Language, 56, 397-425; Hagiwara, H. (1995). The breakdown of functional categories and the economy of derivation. Brain and Language, 50, 92-116]. Such theories predict that morpho-syntactic elements associated with higher nodes in the syntactic tree (complementizers and verb inflections) will be more impaired than elements associated with lower structural positions (negation markers and aspectual verb forms). While this hypothesis has been supported by the results of several studies [Benedet, M. J., Christiansen, J. A., & Goodglass, H. (1998). A cross-linguistic study of grammatical morphology in Spanish- and English-speaking agrammatic patients. Cortex, 34, 309-336; Friedmann, N. (2001). Agrammatism and the psychological reality of the syntactic tree. Journal of Psycholinguistic Research, 30, 71-88; Friedmann, N. (2002). Question production in agrammatism: The tree pruning hypothesis. Brain and Language, 80, 160-187], it has also been challenged on several grounds [Burchert, F., Swoboda-Moll, M., & De Bleser, R. (2005a). Tense and agreement dissociations in German agrammatic speakers: Underspecification vs. hierarchy. Brain and Language, 94, 188-199; Lee, M. (2003). Dissociations among functional categories in Korean agrammatism. Brain and Language, 84, 170-188; Lee, J., Milman, L. H., & Thompson, C. K. (2005). Functional category production in agrammatic speech. Brain and Language, 95, 123-124]. In this paper the question of hierarchical structure was re-examined within the framework of Item Response Theory [IRT, Rasch, G. (1980). Probabilistic models for some intelligence and attainment tests (Expanded ed.). Chicago: University of Chicago Press]. IRT is a probabilistic model widely used in the field of psychometrics to model behavioral constructs as numeric variables. In this study we examined production of functional categories (complementizers, verb inflections, negation markers, and aspectual verb forms) in narrative samples elicited from 18 individuals diagnosed with nonfluent aphasia and 18 matched controls. Data from the aphasic participants were entered into an IRT analysis to test (1) whether production of clausal functional categories can be represented as a variable on a numeric scale; and (2) whether production patterns were consistent with hierarchical syntactic structure. Pearson r correlation coefficients were also computed to determine whether there was a relation between functional category production and other indices of language performance. Results indicate that functional category production can be modeled as a numeric variable using IRT. Furthermore, although variability was observed across individuals, consistent patterns were evident when the data were interpreted within a probabilistic framework. Although functional category production was moderately correlated with a second measure of clausal structure (clause length), it was not correlated with more distant language constructs (noun/verb ratio and WAB A.Q.). These results suggest that functional category production is related to some, but not all, measures of agrammatic language performance.

Initial validity and reliability of the SCCAN: using tailored testing to assess adult cognition and communication.

PURPOSE: The Scales of Cognitive and Communicative Ability for Neurorehabilitation (SCCAN; L. Milman & A. Holland, 2007) was developed in the hospital setting to address changes in assessment practice. The SCCAN was designed to provide an overview of impairment and activity limitations across 8 cognitive scales (Speech Comprehension, Oral Expression, Reading, Writing, Orientation, Attention, Memory, and Problem Solving). The scales were developed using item response theory so that tailored testing could be implemented to reduce test administration time. This research investigated the validity and reliability of the SCCAN. METHOD: A battery of neuropsychological tests was administered to 40 neurologically healthy control participants and 51 participants diagnosed with left-hemisphere pathology, right-hemisphere pathology, or probable Alzheimer's disease. Analyses were performed to assess test sensitivity and specificity, construct validity, administration time, and reliability. RESULTS: The test accurately classified 95% of the control participants and 98% of the participants diagnosed with neurological disorders. Results indicate that the test also differentiated the performance profiles of the 3 clinical populations. In addition, test scores correlated significantly with external measures of the same cognitive areas. Mean administration time was 34 min. Test-retest stability (r = .96, p < .001) and internal consistency (r = .99, p < .001) coefficients were both significant, indicating that tailored testing procedures generated reliable test scores.