Deciphering the mechanisms of phonological therapy in jargon aphasia

Background: Severe word production difficulties remain one of the most challenging clinical symptoms to treat in individuals with jargon aphasia. Clinically, it is important to determine why some individuals with jargon aphasia improve following therapy when others do not. We report a therapy study with AM, an individual with severe neologistic jargon aphasia, and provide a subsequent comparison to previous cases, with the purpose of informing both our theoretical and clinical understanding of jargon aphasia. Aims: This research aimed to investigate AM’s locus of word production deficit and determine the effectiveness of Phonological Component Analysis (PCA) therapy, a phonological cueing therapy, in the re-learning and generalization of naming responses for words. In addition, AM’s performance in therapy, linguistic profile, and ability to engage with therapy/cues were compared in a retrospective analysis with the background linguistic and therapy data of two other individuals with jargon aphasia (P9, Leonard et al., 2008; FF, Bose, 2013), who responded differentially to PCA. This was undertake to explore possible prognostic indicators of phonological therapy for jargon aphasia. Methods and Procedures: A battery of linguistic and neuropsychological tests was used to identify AM’s word production deficit. A single-subject multiple probe design across behaviours was employed to evaluate the effects of PCA therapy on the re-learning and generalization of naming responses. In the retrospective analysis of AM, P9 and FF, we compared differences and similarities in performance on various linguistic tasks, the ability to engage in therapy (i.e., ability to generate and utilize the cues), as well as to retain and maintain cues. Outcomes and Results: AM’s locus of deficit was identified in the mapping between semantics and phonology. PCA was found to be effective in improving naming in two of the three treated word lists during the treatment phase; however, these gains were not maintained. Generalization to untreated picture names was not observed. Findings from the retrospective analysis illustrated that oral reading skills, ability to segment phonological information from words and active engagement with provided cues are likely prerequisites for obtaining robust and long-term gains. Conclusions and Implications: We demonstrated that phonological therapy could be beneficial for the remediation of naming abilities at least in the re-learning phase; however, maintenance and generalization of these gains were limited. This research helps to elucidate the considerations and evaluations necessary for the appropriateness of phonological therapy and candidacy of individuals with jargon aphasia for this treatment approach

Language control and parallel recovery of language in individuals with aphasia

Background: The causal basis of the different patterns of language recovery following stroke in bilingual speakers is not well understood. Our approach distinguishes the representation of language from the mechanisms involved in its control. Previous studies have suggested that difficulties in language control can explain selective aphasia in one language as well as pathological switching between languages. Here we test the hypothesis that difficulties in managing and resolving competition will also be observed in those who are equally impaired in both their languages even in the absence of pathological switching. Aims: To examine difficulties in language control in bilingual individuals with parallel recovery in aphasia and to compare their performance on different types of conflict task. Methods & procedures: Two right-handed, non-native English-speaking participants who showed parallel recovery of two languages after stroke and a group of non-native English-speaking, bilingual controls described a scene in English and in their first language and completed three explicit conflict tasks. Two of these were verbal conflict tasks: a lexical decision task in English, in which individuals distinguished English words from non-words, and a Stroop task, in English and in their first language. The third conflict task was a non-verbal flanker task. Outcomes & Results: Both participants with aphasia were impaired in the picture description task in English and in their first language but showed different patterns of impairment on the conflict tasks. For the participant with left subcortical damage, conflict was abnormally high during the verbal tasks (lexical decision and Stroop) but not during the non-verbal flanker task. In contrast, for the participant with extensive left parietal damage, conflict was less abnormal during the Stroop task than the flanker or lexical decision task. Conclusions: Our data reveal two distinct control impairments associated with parallel recovery. We stress the need to explore the precise nature of control problems and how control is implemented in order to develop fuller causal accounts of language recovery patterns in bilingual aphasia

On natural metalinguistic abilities in aphasia: a preliminary study

Natural metalinguistic abilities, which are put into play without explicit instructions, constitute the cognitive basis for a 'reflexive' use of language, a particular manifestation of the executive function when applied to language and verbal behaviour. This reflexive use entails a specific attentional activity by speakers and hearers with regard to linguistic outputs, and an intentional experience-based control over the language use. Putting into play natural metalinguistic abilities can be considered a significant factor for explaining different kinds of adaptive processes. Our results permit us to conclude that an impairment of metalinguistic abilities is involved in aphasia to different degrees. Moreover, the examination of preserved metalinguistic abilities provides an alternative way for assessing the degree of severity of impaired communicative behaviour by people with aphasia. Our procedure, presumably, will also be useful for suggesting new factors when designing therapeutic programmes

Psychometric properties of discourse measures in aphasia: acceptability, reliability, and validity

BACKGROUND: Discourse in adults with aphasia is increasingly the focus of assessment and therapy research. A broad range of measures is available to describe discourse, but very limited information is available on their psychometric properties. As a result, the quality of these measures is unknown, and there is very little evidence to motivate the choice of one measure over another. AIMS: To explore the quality of a range of discourse measures, targeting sentence structure, coherence, story structure and cohesion. Quality was evaluated in terms of the psychometric properties of acceptability (data completeness and skewness), reliability (inter- and intra-rater), and validity (content, convergent, discriminant and known groups). METHODS & PROCEDURES: Participants with chronic mild-to-moderate aphasia were recruited from community groups. They produced a range of discourses which were grouped into Cinderella and everyday discourses. Discourses were then transcribed orthographically and analyzed using macro- and microlinguistic measures (Story Grammar, Topic Coherence, Local Coherence, Reference Chains and Predicate Argument Structure-PAS). Data were evaluated against standard predetermined criteria to ascertain the psychometric quality of the measures. OUTCOMES & RESULTS: A total of 17 participants took part in the study. All measures had high levels of acceptability, inter- and intra-rater reliability, and had good content validity, as they could be related to a level of the theoretical model of discourse production. For convergent validity, as expected, 8/10 measures correlated with the Western Aphasia Battery-Revised (WAB-R) spontaneous speech scores, and 7/10 measures correlated with the Kissing and Dancing Test (KDT) scores (r ≥ 0.3), giving an overall positive rating for construct validity. For discriminant validity, as predicted, all measures had low correlations with Raven's Coloured Progressive Matrices (RCPM) and WAB-R Auditory Verbal Comprehension scores (r < 0.3), giving an overall positive rating for construct validity. Finally, for known groups validity, all measures indicated a difference between speakers with mild and moderate aphasia except for the Local Coherence measures. Overall, Story Grammar, Topic Coherence, Reference Chains and PAS emerged as the strongest measures in the current study because they achieved the predetermined thresholds for quality in terms of each of the psychometric parameters profiled. CONCLUSIONS & IMPLICATIONS: The current study is the first to psychometrically profile measures of discourse in aphasia. It contributes to the field by identifying Story Grammar, Topic Coherence, Reference Chains and PAS as the most psychometrically robust discourse measures yet profiled with speakers with aphasia. Until further data are available indicating the strength of other discourse measures, caution should be applied when using them

Syntactic processing as a marker for cognitive impairment in amyotrophic lateral sclerosis

Despite recent interest in cognitive changes in patients with amyotrophic lateral sclerosis (ALS), investigations of language function looking at the level of word, sentence and discourse processing are relatively scarce. Data were obtained from 26 patients with sporadic ALS and 26 healthy controls matched for age, education, gender, anxiety, depression and executive function performance. Standardized language tasks included confrontation naming, semantic access, and syntactic comprehension. Quantitative production analysis (QPA) was used to analyse connected speech samples of the Cookie Theft picture description task. Results showed that the ALS patients were impaired on standardized measures of grammatical comprehension and action/verb semantics. At the level of discourse, ALS patients were impaired on measures of syntactic complexity and fluency; however, the latter could be better explained by disease related factors. Discriminant analysis revealed that syntactic measures differentiated ALS patients from controls. In conclusion, patients with ALS exhibit deficits in receptive and expressive language on tasks of comprehension and connected speech production, respectively. Our findings suggest that syntactic processing deficits seem to be the predominant feature of language impairment in ALS and that these deficits can be detected by relatively simple language tests

A Systematic Review of Semantic Feature Analysis Therapy Studies for Aphasia

Purpose : The purpose of this study was to review treatment studies of semantic feature analysis (SFA) for persons with aphasia . The review documents how SFA is used, appraises the quality of the included studies and evaluates the efficacy of SFA. Methods : The following electronic databases were systematically searched (last search February 2017) : Academic Search Complete; CINAHL Plus; E -journals; Health Policy Reference Centre; MEDLINE; PsycART ICLES; PsycINFO; and SocINDEX. The quality of the included studies was rated. Clinical efficacy was determined by calculating effect sizes ( Cohen’s d ) or percent of non-overlapping data when d could not be calculated. Results: Twenty -one studies were reviewed reporting on 55 persons with aphasia. SFA was used in six different types of studies: confrontation naming of nouns, of verbs , connected speech /discourse, group, multilingual and studies where SFA was compared with other approaches . The quality of included studies was high [ Single Case Experimental Design Scale (SCED S) average (range) =9.55 ( 8.0- 11 )]. Naming of trained items improved for 45 participants ( 81.82%). Effect sizes indicated there was a small treatment effect. Conclusions: SFA leads to p ositive outcomes despite the variability of treatment procedures, dosage, duration and variations to the traditional SFA protocol. Further research is warranted to examine the efficacy of SFA and generalization effects in larger controlled studies

Oral and written picture description in individuals with aphasia

Aim: To explore the differences between the oral and written description of a picture in individuals with chronic aphasia (IWA) and healthy controls. Descriptions were controlled for productivity, efficiency, grammatical organization, substitution behavior and discourse organization. Method: 50 IWA and 50 healthy controls matched for age, gender and education, provided an oral and written description of a black and white situational drawing from the Dutch version of the Comprehensive Aphasia Test. Between- and within-group analyses were carried out and the reliability of the test instrument was assessed. Results: The language samples of the healthy controls were more elaborate, more efficient, syntactically richer, more coherent and consisted of fewer spoken and written language errors than the samples of the IWA. Within-group comparisons showed that connected writing is more sensitive than connected speech to capture aphasic symptoms. Conclusion: The analysis of both modalities (speech and writing) at discourse level allows to simultaneously assess microlinguistic and macrolinguistic skills and their potential interrelations in a given IWA. Connected writing appears to be more sensitive in discriminating IWA from healthy controls than connected speech. This method for analyzing language samples should, however, be used in conjunction with other assessment tools

Comparing uni-modal and multi-modal therapies for improving writing in acquired dysgraphia after stroke.

Writing therapy studies have been predominantly uni-modal in nature; i.e., their central therapy task has typically been either writing to dictation or copying and recalling words. There has not yet been a study that has compared the effects of a uni-modal to a multi-modal writing therapy in terms of improvements to spelling accuracy. A multiple-case study with eight participants aimed to compare the effects of a uni-modal and a multi-modal therapy on the spelling accuracy of treated and untreated target words at immediate and follow-up assessment points. A cross-over design was used and within each therapy a matched set of words was targeted. These words and a matched control set were assessed before as well as immediately after each therapy and six weeks following therapy. The two approaches did not differ in their effects on spelling accuracy of treated or untreated items or degree of maintenance. All participants made significant improvements on treated and control items; however, not all improvements were maintained at follow-up. The findings suggested that multi-modal therapy did not have an advantage over uni-modal therapy for the participants in this study. Performance differences were instead driven by participant variables

What does a cue do? Comparing phonological and semantic cues for picture naming in aphasia

Purpose: Impaired naming is one of the most common symptoms in aphasia, often treated with cued picture naming paradigms. It has been argued that semantic cues facilitate the reliable categorisation of the picture, and phonological cues facilitate the retrieval of target phonology. To test these hypotheses, we compared the effectiveness of phonological and semantic cues in picture naming for a group of individuals with aphasia. To establish the locus of effective cueing, we also tested whether cue type interacted with lexical and image properties of the targets. Method: Individuals with aphasia (n=10) were tested with a within-subject design. They named a large set of items (n=175) four times. Each presentation of the items was accompanied by a different cueing condition (phonological, semantic, non-associated word and tone). Item level variables for the targets (i.e., phoneme length, frequency, imageability, name agreement and visual complexity) were used to test the interaction of cue type and item variables. Naming accuracy data was analysed using generalised linear mixed effects models. Results: Phonological cues were more effective than semantic cues, improving accuracy across individuals. However, phonological cues did not interact with phonological or lexical aspects of the picture names (e.g., phoneme length, frequency). Instead, they interacted with properties of the picture itself (i.e., visual complexity), such that phonological cues improved naming accuracy for items with low visual complexity. Conclusions: The findings challenge the theoretical assumptions that phonological cues map to phonological processes. Instead, phonological information benefits the earliest stages of picture recognition, aiding the initial categorization of the target. The data help to explain why patterns of cueing are not consistent in aphasia, i.e., it is not the case that phonological impairments always benefit from phonological cues and semantic impairments form semantic cues. A substantial amount of the literature in naming therapy focuses on picture naming paradigms. Therefore, the results are also critically important for rehabilitation, allowing for therapy development to be more rooted in the true mechanisms through which cues are processed