Grammatical Class Effects Across Impaired Child and Adult Populations

The Effectiveness of Transcranial Magnetic Stimulation (TMS) Paradigms as Treatment Options for Recovery of Language Deficits in Chronic Poststroke Aphasia

Background

In an effort to boost aphasia recovery, modern rehabilitation, in addition to speech and language therapy (SALT), is increasingly incorporating noninvasive methods of brain stimulation. The present study is aimed at investigating the effectiveness of two paradigms of neuronavigated repetitive transcranial magnetic stimulation (rTMS): (i) 1 Hz rTMS and (ii) continuous theta burst stimulation (cTBS) each as a standalone treatment for chronic aphasia poststroke.

Methods

A single subject experimental design (SSED) trial was carried out in which six people with aphasia (PWA) were recruited, following a single left hemispheric stroke more than six months prior to the study. Three individuals were treated with 1 Hz rTMS, and the remaining three were treated with cTBS. In all cases, TMS was applied over the right pars triangularis (pTr). Language assessment, with standardized and functional measures, and cognitive evaluations were carried out at four time points: twice prior to treatment (baseline), one day immediately posttreatment, and at follow-up two months after treatment was terminated. Quality of life (QoL) was also assessed at baseline and two months posttreatment. In addition, one of the participants with severe global aphasia was followed up again one and two years posttherapy.

Results

For all participants, both rTMS paradigms (1 Hz rTMS and cTBS) generated trends towards improvement in several language skills (i.e., verbal receptive language, expressive language, and naming and reading) one day after treatment and/or two months after therapy. Rated QoL remained stable in three individuals, but for the other three, the communication scores of the QoL were reduced, while two of them also showed a decline in the psychological scores. The participant that was treated with cTBS and followed for up to two years showed that the significant improvement she had initially exhibited in comprehension and reading skills two months after TMS (1^st follow-up) was sustained for at least up to two years.

Conclusion

From the current findings, it is suggested that inhibitory TMS over the right pTr has the potential to drive neuroplastic changes as a standalone treatment that facilitates language recovery in poststroke aphasia.

Neural processing of nouns and verbs in spontaneous speech of patients with schizophrenia

Previous fMRI-studies investigating the production of nouns and verbs in healthy participants reported predominantly activation in the left inferior frontal gyrus (IFG) for both classes of words with increased neural responses for verbs. To date, comparable imaging data for spontaneous speech in patients with schizophrenia is missing. These results are novel and may contribute to understand the neural basis of noun and verb production in a "natural" environment. Fifteen patients with schizophrenia and fifteen healthy control participants described pictures for one minute each while BOLD signal changes were measured with fMRI. In an event-related design, activations related to noun and verb production were extracted in the imaging analysis. Imaging results revealed increased activation for nouns and decreased activation for verbs in the left IFG in the patients. A post-hoc analysis revealed that patients produced significantly more transitive verbs which were negatively associated with activation in the left IFG. We conclude that a subtle linguistic processing deficit in schizophrenia may lead to an increased use of transitive as compared to intransitive verbs in connected speech and to a deviant pattern of brain activation related to the processing of verbs.

Naming error in multiple sclerosis patients: A pilot study in Isfahan, Iran

Background:

Although cognitive impairment is common in multiple sclerosis (MS) patients, language difficulties are controversy and little information is available on nonEnglish languages. Therefore, the present cross-sectional study was conducted to assess the naming accuracy in Persian relapsing-remitting MS (RRMS) patients.

Materials and Methods:

Thirty RRMS patients were recruited from Kashani Comprehensive MS Center, Isfahan, Iran. Their performance on measures of mini mental state examination (MMSE), Expanded Disability Status Scale, and Naming Test was compared with control participants.

Results:

MS patients were found to have much more naming errors than the control group (2.1 ± 1.8 vs. 0.54 ± 1.1 P = 0.02). Average MMSE score of MS patients was 27.23 (range = 18–30, standard deviation [SD] = 2) versus 28.96 (range = 19–30, SD = 3.2) in controls.

Conclusion:

The present study suggests that naming ability can be impaired in RRMS regardless of disability score. Specific language function tests including naming should be considered in the process of evaluating and rehabilitating patients with MS.

Lexical access in a bilingual speaker with dementia: Changes over time

In this article, we explore the naming skills of a bilingual English-Norwegian speaker diagnosed with Primary Progressive Aphasia, in each of his languages across three different speech contexts: confrontation naming, semi-spontaneous narrative (picture description), and conversation, and at two points in time: 12 and 30 months post diagnosis, respectively. The results are discussed in light of two main theories of lexical retrieval in healthy, elderly speakers: the Transmission Deficit Hypothesis and the Inhibitory Deficit Theory. Our data show that, consistent with the participant's premorbid use of and proficiency in the two languages, his performance in his L2 is lower than in his L1, but this difference diminishes as the disease progresses. This is the case across the three speech contexts; however, the difference is smaller in the narrative task, where his performance is very low in both languages already at the first measurement point. Despite his word finding problems, he is able to take active part in conversation, particularly in his L1 and more so at the first measurement point. In addition to the task effect, we find effects of word class, frequency, and cognateness on his naming skills. His performance seems to support the Transmission Deficit Hypothesis. By combining different tools and methods of analysis, we get a more comprehensive picture of the impact of the dementia on the speaker's languages from an intra-individual as well as an inter-individual perspective, which may be useful in research as well as in clinical practice.

The Locus Preservation Hypothesis: Shared Linguistic Profiles across Developmental Disorders and the Resilient Part of the Human Language Faculty

Grammatical markers are not uniformly impaired across speakers of different languages, even when speakers share a diagnosis and the marker in question is grammaticalized in a similar way in these languages. The aim of this work is to demarcate, from a cross-linguistic perspective, the linguistic phenotype of three genetically heterogeneous developmental disorders: specific language impairment, Down syndrome, and autism spectrum disorder. After a systematic review of linguistic profiles targeting mainly English-, Greek-, Catalan-, and Spanish-speaking populations with developmental disorders (n = 880), shared loci of impairment are identified and certain domains of grammar are shown to be more vulnerable than others. The distribution of impaired loci is captured by the Locus Preservation Hypothesis which suggests that specific parts of the language faculty are immune to impairment across developmental disorders. Through the Locus Preservation Hypothesis, a classical chicken and egg question can be addressed: Do poor conceptual resources and memory limitations result in an atypical grammar or does a grammatical breakdown lead to conceptual and memory limitations? Overall, certain morphological markers reveal themselves as highly susceptible to impairment, while syntactic operations are preserved, granting support to the first scenario. The origin of resilient syntax is explained from a phylogenetic perspective in connection to the "syntax-before-phonology" hypothesis.

Diagnosing bilectal children with SLI: Determination of identification accuracy

Very little is known about diagnosing specific language impairment (SLI) in children who are exposed daily to a dialect (community language) and a standard variety (school instruction). The research reported here examines the specificity and sensitivity of language tests used so far to evaluate language performance in the context of diglossia (Cyprus). Sixteen children with SLI aged 5-9 years and 22 age-matched typically developing children were examined on a range of language tests modified to include dialectal differences. Properties of each test were evaluated through logistic regression analysis in order to identify children with SLI. The analysis revealed that many of the tests used are sufficiently accurate concerning sensitivity and specificity levels. Furthermore, a combination of tests is proposed as a good tool for diagnostic purposes. Speech and language therapists as well as researchers can now rely on an accurate diagnostic procedure within a practice-based evidence framework.