Focusing on the locus of the breakdown for treatment of anomia: a pilot study.

The primary goal of this study was to evaluate the treatment effects of semantic feature analysis (SFA) and phonological components analysis (PCA) on word retrieval processing in persons with aphasia (PWAs). After identifying the locus of the breakdown in lexical retrieval processing, 15 monolingual native Persian speakers with aphasia were divided into two groups. After three naming trials, participants with dominant semantic deficits received SFA, and participants with primary phonological deficits were provided with PCA three times a week for eight weeks. Both approaches improved participants' naming and performance on language tests, including spontaneous speech, repetition, comprehension, and semantic processing. However, the correct naming of treated and untreated items was higher in mild-to-moderate participants, with mostly circumlocution and semantic paraphasias in the SFA group. The same holds for mild-to-moderate participants with mostly phonemic paraphasia who received PCA therapy. Moreover, the results showed that participants' baseline naming performance and semantic abilities could be associated with the treatment outcomes. Although limited by a lack of a control group, this study provided evidence supporting the possible benefits of focusing on the locus of the breakdown for treating anomia through SFA and PCA approaches, specifically in participants with mild to moderate aphasia. However, for those with severe aphasia, the treatment choice may not be as straightforward because several variables are likely to contribute to this population's word-finding difficulties. Replication with larger, well-stratified samples, use of a within-subjects alternating treatment design and consideration of treatments' long-term effects are required to better ascertain the effects of focusing on the locus of breakdown for treatment of anomia.

Treatment of verb tense inflection and sentence production in Persian individuals with agrammatism.

Production of verb morphology, especially tense inflection, is usually impaired in individuals with agrammatism. There have been relatively few studies on treatment of verb tense inflection in agrammatic aphasia. In this study we adapted ACTION (a linguistically motivated treatment) to Persian language, to treat the production of regular and irregular verbs separately in sentence context. A single-subject multiple-baseline across behaviors design was used to establish the treatment effect. Using a non-probable convenience sampling, four Persian agrammatic patients with Broca's aphasia resulting from cerebrovascular accident (CVA) were recruited for this study. Two participants received treatment first for regular verbs (Phase 1, 4 weeks), and then for irregular verbs (Phase 2, 4 weeks). The other two participants received treatment in reverse order. In the final phase of treatment (Phase 3, 4 weeks), all 4 participants underwent a sentence construction treatment. All participants showed improvement in the production of trained tenses. Treatment also generalized to production of untrained regular verbs while generalization to irregular verbs was modest. Furthermore, improvement was found on narrative scores (e.g. MLU) after treatment. These findings suggest that Persian individuals with agrammatism could be trained to correctly apply temporal information to verb inflection in elicited speech.

A narrative review of the anatomy and function of the white matter tracts in language production and comprehension.

Much is known about the role of cortical areas in language processing. The shift towards network approaches in recent years has highlighted the importance of uncovering the role of white matter in connecting these areas. However, despite a large body of research, many of these tracts' functions are not well-understood. We present a comprehensive review of the empirical evidence on the role of eight major tracts that are hypothesized to be involved in language processing (inferior longitudinal fasciculus, inferior fronto-occipital fasciculus, uncinate fasciculus, extreme capsule, middle longitudinal fasciculus, superior longitudinal fasciculus, arcuate fasciculus, and frontal aslant tract). For each tract, we hypothesize its role based on the function of the cortical regions it connects. We then evaluate these hypotheses with data from three sources: studies in neurotypical individuals, neuropsychological data, and intraoperative stimulation studies. Finally, we summarize the conclusions supported by the data and highlight the areas needing further investigation.

Mechanisms of brain activation following naming therapy in aphasia: A systematic review on task-based fMRI studies.

The pattern of brain neuroplasticity after naming therapies in patients with aphasia can be evaluated using task-based fMRI. This article aims to review studies investigating brain reorganization after semantic and phonological-based anomia therapy that used picture-naming fMRI tasks. We searched for those articles that compared the activation of brain areas before and after aphasia therapies in the PubMed and the EMBASE databases from 1993 up to April 2020. All studies (single-cases or group designs) on anomia treatment in individuals with acquired aphasia were reviewed. Data were synthesized descriptively through tables to allow the facilitated comparison of the studies. A total of 14 studies were selected and reviewed. The results of the reviewed studies demonstrated that the naming improvement is associated with changes in the activation of cortical and subcortical brain areas. This review highlights the need for a more systematic investigation of the association between decreased and increased activation of brain areas related to anomia therapy. Also, more detailed information about factors influencing brain reorganization is required to elucidate the neural mechanisms of anomia therapy. Overall, regarding the theoretical and clinical aspects, the number of studies that used intensive protocol is growing, and based on the positive potential of these treatments, they could be suitable for the rehabilitation of people with aphasia.

Extreme capsule is a bottleneck for ventral pathway.

As neuroscience literature suggests, extreme capsule is considered a whiter matter tract. Nevertheless, it is not clear whether extreme capsule itself is an association fiber pathway or only a bottleneck for other association fibers to pass. Via our review, investigating anatomical position, connectivity and cognitive role of the bundles in extreme capsule, and by analyzing data from the dissection, it can be argued that extreme capsule is probably a bottleneck for the passage of uncinated fasciculus (UF) and inferior fronto-occipital fasciculus (IFOF), and these fasciculi are responsible for the respective roles in language processing.