Despite considerable recent progress in understanding the underlying neurobiology of primary progressive aphasia (PPA) syndromes, relatively little attention has been directed toward the examination of behavioral interventions that may lessen the pervasive communication problems associated with PPA. In this study, we report on an individual with a behavioral profile and cortical atrophy pattern consistent with the logopenic variant of PPA. At roughly two-and-a-half years post onset, his marked lexical retrieval impairment prompted administration of a semantically based intervention to improve word retrieval. The treatment was designed to improve self-directed efforts to engage the participant’s relatively preserved semantic system in order to facilitate word retrieval. His positive response to an intensive (2-week) dose of behavioral treatment was associated with improved lexical retrieval of items within trained categories, and generalized improvement for naming of untrained items that lasted over a 6-month follow-up interval. These findings support the potential value of intensive training to achieve self-directed strategic compensation for lexical retrieval difficulties in logopenic PPA. Additional insight was gained regarding the neural regions that supported improved performance by the administration of a functional magnetic resonance imaging protocol before and after treatment. In the context of a picture-naming task, post-treatment fMRI showed increased activation of left dorsolateral prefrontal regions that have been implicated in functional imaging studies of generative naming in healthy individuals. The increased activation in these frontal regions that were not significantly atrophic in our patient (as determined by voxel-based morphometry) is consistent with the notion that neural plasticity can support compensation for specific language loss, even in the context of progressive neuronal degeneration.

Few studies have investigated language recovery patterns and the mechanisms of crossed bilingual aphasia following a subcortical stroke. In particular, Korean-Japanese crossed bilingual aphasia has not been reported. A 47-year-old, right-handed man was diagnosed with an extensive right basal ganglia hemorrhage. He was bilingual, fluent in both Korean and Japanese. After his stroke, the patient presented with crossed aphasia. We investigated changes in the Korean (L1) and Japanese (L2) language recovery patterns. Both Korean and Japanese versions of the Western Aphasia Battery (WAB) were completed one month after the stroke, and functional magnetic resonance imaging (fMRI) was performed using picture-naming tasks. The WAB showed a paradoxical pattern of bilingual aphasia, with an aphasia quotient (AQ) of 32 for Korean and 50.6 for Japanese, with Broca's aphasia. The patient scored better in the Japanese version of all domains of the tests. The fMRI study showed left lateralized activation in both language tasks, especially in the inferior frontal gyrus. After six months of language therapy targeting L1, the Korean-WAB score improved significantly, while the Japanese-WAB score showed slight improvement. In this case, the subcortical lesion contributed to crossed bilingual aphasia more highly affecting L1 due to loss of the cortico-subcortical control mechanism in the dominant hemisphere. The paradoxical pattern of bilingual aphasia disappeared after lengthy language therapy targeting L1, and the therapy effect did not transfer to L2. Language recovery in L1 might have been accomplished by reintegrating language networks, including the contralesional language homologue area in the left hemisphere.

Objectives:The purpose of the current study was to identify characteristics of acquired phonological dyslexia in Korean patients with brain damage and relationship between those characteristics and brain lesions. Methods: Thirty normal controls and six brain-damaged patients participated in the study. Assessment tasks of orthographic, phonological, and semantic processing were developed based on the cognitive model of single word reading and were administered to participants to evaluate reading ability. Orthographic processing assessment was performed to evaluate whether participants recognized letters and visual word forms. Phonological tasks assessed the ability to segment and manipulate sounds in words. A semantic task was performed in order to examine if semantic knowledge was preserved. Reading aloud task of words/nonwords was also performed with the intention of identifying characteristics of phonological dyslexia. Results: There was a significant difference in orthographic, semantic, and reading aloud performance between the normal control group and patient group. The patient group showed relatively preserved orthographic and semantic processing although most of them were not able to perform the phonological tasks. Significant differences between word and nonword reading aloud in patients indicated features of phonological dyslexia. Conclusion: Orthographic, phonological, and semantic tasks were administered to participants with perisylvian lesion. Our results showed impaired phonological processing and nonword reading compared to relatively preserved performance on orthographic, semantic tasks and word reading. These results are consistent with previous studies on phonological dyslexia, and characteristics of acquired phonological dyslexia in the Korean language were associated with perisylvian language areas.

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