Agrammatism in aphasia is not a homogeneous syndrome, but a characterization of a nonuniform set of language behaviors in which grammatical markers and complex syntactic structures are omitted, simplified, or misinterpreted. In a sample of 71 left-hemisphere stroke survivors, syntactic processing was quantified with the Northwestern Assessment of Verbs and Sentences (NAVS). Classification analyses were used to assess the relation between NAVS performance and morphosyntactically reduced speech in picture descriptions. Voxel-based and connectivity-based lesion-symptom mapping were applied to investigate neural correlates of impaired syntactic processing. Despite a nonrandom correspondence between NAVS performance and morphosyntactic production deficits, there was variation in individual patterns of syntactic processing. Morphosyntactically reduced production was predicted by lesions to left-hemisphere inferior frontal cortex. Impaired verb argument structure production was predicted by damage to left-hemisphere posterior superior temporal and angular gyrus, as well as to a ventral pathway between temporal and frontal cortex. Damage to this pathway was also predictive of impaired sentence comprehension and production, particularly of noncanonical sentences. Although agrammatic speech production is primarily predicted by lesions to inferior frontal cortex, other aspects of syntactic processing rely rather on regional integrity in temporoparietal cortex and the ventral stream.

The present article introduces a Russian-language database of 375 action pictures and associated verbs with normative data. The pictures were normed for name agreement, conceptual familiarity, and subjective visual complexity, and measures of age of acquisition, imageability, and image agreement were collected for the verbs. Values of objective visual complexity, as well as information about verb frequency, length, argument structure, instrumentality, and name relation, are also provided. Correlations between these parameters are presented, along with a comparative analysis of the Russian name agreement norms and those collected in other languages. The full set of pictorial stimuli and the obtained norms may be freely downloaded from http://neuroling.ru/en/db.htm for use in research and for clinical purposes.

Previous research has shown that comprehenders do not always conduct a full (re)analysis of temporarily ambiguous "garden-path" sentences. The present study used a sentence-picture matching task to investigate what kind of representations are formed when full reanalysis is not performed: Do comprehenders "blend" two incompatible representations as a result of shallow syntactic processing or do they erroneously maintain the initial incorrect parsing without incorporating new information, and does this vary with age? Twenty-five younger and 15 older adults performed a multiple-choice sentence-picture matching task with stimuli including early-closure garden-path sentences. The results suggest that the type of erroneous representation is affected by linguistic variables, such as sentence structure, verb type, and semantic plausibility, as well as by age. Older adults' response patterns indicate an increased reliance on inferencing based on lexical and semantic cues, with a lower bar for accepting an initial parse and with a weaker drive to reanalyse a syntactic representation. Among younger adults, there was a tendency to blend two representations into a single interpretation, even if this was not licensed by the syntax.

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