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This review synthesizes findings from 117 studies that have manipulated various picture-word interference (PWI) task properties to establish whether semantic context effects reflect competitive word retrieval, or are driven by noncompetitive processes. Manipulations of several PWI task parameters (e.g., distractor visibility) have produced contradictory findings. Evidence derived from other manipulations (e.g., visual similarity between targets and distractors) has been scarce. Some of the manipulations that have furnished reliable effects (e.g., distractor taboo interference) do not discriminate between the rival theories. Interference from nonverbal distractors has been shown to be a genuine effect dependent on adequate lexicalization of interfering stimuli. This supports the swinging lexical network hypothesis and the selection-by-competition-with-competition-threshold hypothesis while undermining one of the assumptions of the response exclusion hypothesis. The contribution of pre-lexical processes, such as an interaction between distractor processing and conceptual encoding of the target to the overall semantic context effect is far from settled.

Background: Evidence-based recommendations for a core outcome set (COS; minimum set of outcomes) for aphasia treatment research have been developed (the Research Outcome Measurement in Aphasia--ROMA, COS). Five recommended core outcome constructs: communication, language, quality of life, emotional well-being and patient-reported satisfaction/impact of treatment, were identified through three international consensus studies. Constructs were paired with outcome measurement instruments (OMIs) during an international consensus meeting (ROMA-1). Before the current study (ROMA-2), agreement had not been reached on OMIs for the constructs of communication or patient-reported satisfaction/impact of treatment. Aim: To establish consensus on a communication OMI for inclusion in the ROMA COS. Methods & Procedures: Research methods were based on recommendations from the Core Outcome Measures in Effectiveness Trials (COMET) Initiative. Participants with expertise in design and conduct of aphasia trials, measurement instrument development/testing and/or communication outcome measurement were recruited through an open call. Before the consensus meeting, participants agreed on a definition of communication, identified appropriate OMIs, extracted their measurement properties and established criteria for their quality assessment. During the consensus meeting they short-listed OMIs and participants without conflicts of interest voted on the two most highly ranked instruments. Consensus was defined a priori as agreement by [greater than or equal to] 70% of participants. Outcomes & Results: In total, 40 researchers from nine countries participated in ROMA-2 (including four facilitators and three-panel members who participated in pre-meeting activities only). A total of 20 OMIs were identified and evaluated. Eight short-listed communication measures were further evaluated for their measurement properties and ranked. Participants in the consensus meeting (n = 33) who did not have conflicts of interest (n = 29) voted on the top two ranked OMIs: The Scenario Test (TST) and the Communication Activities of Daily Living--3 (CADL-3). TST received 72% (n = 21) of 'yes' votes and the CADL-3 received 28% (n = 8) of 'yes' votes. Conclusions & Implications: Consensus was achieved that TST was the preferred communication OMI for inclusion in the ROMA COS. It is currently available in the original Dutch version and has been adapted into English, German and Greek. Further consideration must be given to the best way to measure communication in people with mild aphasia. Development of a patient-reported measure for satisfaction with/impact of treatment and multilingual versions of all OMIs of the COS is still required. Implementation of the ROMA COS would improve research outcome measurement and the quality, relevance, transparency, replicability and efficiency of aphasia treatment research.

Background: Verbal fluency tasks are routinely used in clinical assessment and research studies of aphasia. People with aphasia produce fewer items in verbal fluency tasks. It remains unclear if their output is limited solely by their lexical difficulties and/or has a basis in their executive control abilities. Recent research has illustrated that detailed characterization of verbal fluency performance using temporal characteristics of words retrieved, clustering and switching, and pause durations, along with separate measures of executive control stands to inform our understanding of the lexical and cognitive underpinnings of verbal fluency in aphasia. Aims: To determine the locus of the verbal fluency difficulties in aphasia, we compared semantic and letter fluency trials between people with aphasia and healthy control participants using a wide range of variables to capture the performance between the two groups. The groups were also tested on separate measures of executive control to determine the relationship amongst these tasks and fluency performance. Methods & Procedures: Semantic (animal) and letter (F, A, S) fluency data for 60s trials were collected from 14 people with aphasia (PWA) and 24 healthy adult controls (HC). Variables, such as number of correct responses, clustering and switching analyses, were performed along with temporal measures of the retrieved words (response latencies) and pause durations. Participants performed executive control tasks to measure inhibitory control, mental-set shifting and memory span. Outcomes & Results: Compared with HC, PWA produced fewer correct responses, showed greater difficulty with the letter fluency condition, were slower in getting started with the trials, showed slower retrieval times as noted in within- and between-cluster pause durations, and switched less often. Despite these retrieval difficulties, PWA showed a similar decline in the rate of recall to HC, and had similar cluster size. Executive control measures correlated primarily with the letter fluency variables: mostly for PWA and in one instance for HC. Conclusions & Implications: Poorer performance for PWA is a combination of difficulties in both the lexical and executive components of the verbal fluency task. Our findings highlight the importance of detailed characterization of fluency performance in deciphering the underlying mechanism of retrieval difficulties in aphasia, and illustrate the importance of using letter fluency trials to tap into executive control processes.

Background: Mental capacity legislation in the UK is designed to safeguard the rights of people who may need support, or may be unable, to make autonomous decisions. Very limited evidence has been published about the impact of the COVID-19 pandemic on the application of mental capacity legislation and, to our knowledge, none on the ability of speech and language therapists (SLTs) to support people with communication disabilities to engage in decision-making. Aims: To describe how UK SLTs supported people with communication disabilities to make decisions and participate in mental capacity assessments, best interests decision-making and advance care planning during the COVID-19 pandemic. Methods & Procedures: This descriptive, cross-sectional study used an online survey to collect quantitative and qualitative data about SLTs' practice experiences between August and November 2020. SLTs working with a range of adult clinical populations in different care settings were sampled purposively from all UK jurisdictions. Participants were recruited through professional networks and social media. Quantitative data were summarized using descriptive statistics. Qualitative data were analysed thematically. Outcomes & Results: Data were collected from 107 SLTs working in a range of settings across all four UK nations. The sample included SLTs working with people with neurological conditions, learning disabilities, mental health conditions and acute confusion. The need for SLT support appeared to increase during the pandemic. Most respondents were still able to offer support; however, the amount and nature of support varied. Quality of support was impacted by adjustments associated with social distancing and infection control restrictions. Personal protective equipment (PPE) was identified as a barrier to communication. Indirect working methods (e.g., telehealth) were inaccessible to some people with communication disabilities. Most respondents felt confident that legal requirements were upheld, but suggested this group was less able to engage in decision-making and had reduced access to support to manage their own health conditions. Conclusions & Implications: Some SLT services were limited in their ability to meet the decision-making support needs of people with communication disabilities during the COVID-19 pandemic due to structural and systemic barriers. This suggests that existing inequities in the provision of care for people with communication disabilities in the UK were amplified during the pandemic.

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 with previous cases, with the purpose of informing both our theoretical and clinical understanding of jargon aphasia. Aims: 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 and FF), who responded differentially to PCA. This was undertake to explore possible prognostic indicators of phonological therapy for jargon aphasia. Methods & 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 use the cues), as well as to retain and maintain cues. Outcomes & 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, the ability to segment phonological information from words and active engagement with provided cues are likely prerequisites for obtaining robust and long-term gains. Conclusions & 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.

Petroleum‐based plastics levy significant environmental and economic costs that can be alleviated with sustainably sourced, biodegradable, and bio‐based polymers such as polyhydroxyalkanoates (PHAs). However, industrial‐scale production of PHAs faces barriers stemming from insufficient product yields and high costs. To address these challenges, we must look beyond the current suite of microbes for PHA production and investigate non‐model organisms with versatile metabolisms. In that vein, we assessed PHA production by the photosynthetic purple non‐sulfur bacteria (PNSB) Rhodomicrobium vannielii and Rhodomicrobium udaipurense. We show that both species accumulate PHA across photo‐heterotrophic, photo‐hydrogenotrophic, photo‐ferrotrophic, and photo‐electrotrophic growth conditions, with either ammonium chloride (NH4Cl) or dinitrogen gas (N2) as nitrogen sources. Our data indicate that nitrogen source plays a significant role in dictating PHA synthesis, with N2 fixation promoting PHA production during photoheterotrophy and photoelectrotrophy but inhibiting production during photohydrogenotrophy and photoferrotrophy. We observed the highest PHA titres (up to 44.08 mg/L, or 43.61% cell dry weight) when cells were grown photoheterotrophically on sodium butyrate with N2, while production was at its lowest during photoelectrotrophy (as low as 0.04 mg/L, or 0.16% cell dry weight). We also find that photohydrogenotrophically grown cells supplemented with NH4Cl exhibit the highest electron yields – up to 58.89% – while photoheterotrophy demonstrated the lowest (0.27%–1.39%). Finally, we highlight superior electron conversion and PHA production compared to a related PNSB, Rhodopseudomonas palustris TIE‐1. This study illustrates the value of studying non‐model organisms like Rhodomicrobium for sustainable PHA production and indicates future directions for exploring PNSB metabolisms. [ABSTRACT FROM AUTHOR]

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 categorization 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) 4 times. Each presentation of the items was accompanied by a different cueing condition (phonological, semantic, nonassociated 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 were analyzed using generalized 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; that is, 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.

The subjective experience of neurological symptoms provides useful information for assessment, intervention and care. However, research in the subjective experience of aphasia is limited. Word production difficulties are universal to aphasia, and interdisciplinary research has produced sophisticated models of the multiple stages and processes involved. Critically, this word-production research does not incorporate the subjective experience of symptoms. We carried out a metaphor-led discourse analysis on autobiographical accounts written by people with aphasia, to determine whether subjective descriptions of word finding difficulties are consistent with the stages and processes of psycholinguistic models. Metaphor-led discourse analysis was used to identify, code and interpret metaphorical expressions describing word production difficulties in 12 English-language autobiographical accounts written by people with aphasia. These expressions were then analysed to determine the systematic metaphors (i.e., the related concepts which are used consistently to describe a particular topic). Two distinct types of systematic metaphor emerged in the analysis: conventional systematic metaphors frequently recurring throughout all or most of the accounts; novel systematic metaphors used in one or two extended passages in an overlapping subset of the accounts. 4020 metaphorical expressions described word production, predominantly using conventional metaphors about communication and cognition. The conventional metaphor WORD-PRODUCTION AS MOVING OBJECTS OUT OF A CONTAINER was the most prevalent, with elaborations and variations allowing mapping of different symptoms. Other conventional metaphors included: WORD PRODUCTION AS A JOURNEY/HUNTING/HERDING THROUGH A LANDSCAPE, allowing description of effortful or partial retrieval, neuroplastic recovery, and internal strategies; APHASIA AS BODILY IMPAIRMENT, which described various symptoms in terms of different body parts, including self-monitoring difficulties; and APHASIA AS FRAGMENTATION AND PERSONIFICATION OF SELF and SELF AS MACHINE/COMPUTER to describe a disrupted sense of agency and attention. Novel systematic metaphors were used to describe certain symptoms: APHASIA AS SILENCE and APHASIA AS SPIRITUAL EXPERIENCE were used to describe a lack of 'inner speech', and APHASIA AS A DISMEMBERED TREE to describe problems making semantic associations. This research demonstrates the many consistencies of subjective descriptions of word production difficulties in aphasia with theoretical models, but also shows that some subjectively salient symptoms, in particular attentional and self-monitoring difficulties, and a lack of inner speech, are not captured by all theoretical models. Careful attention to the way that people with aphasia describe their symptoms can provide a valuable source of information to be integrated with objective measures. [ABSTRACT FROM AUTHOR]

Introduction: Posterior cortical atrophy (PCA) is a neurodegenerative syndrome characterized by progressive impairment in visuospatial and perceptual function linked to atrophy of the occipito-parietal cortex. Besides the salient visual impairment, several studies have documented subtle changes in language may also be present. Sentence repetition is a highly constrained linguistic task involving multiple linguistic and cognitive processes and have been shown to be impaired in other AD spectrum disorders, with little consensus on its relevance in PCA. This aim of this study was to further delineate the linguistic and cognitive features of impaired language in PCA using a sentence repetition task. Method: Seven PCA patients and 16 healthy controls verbally repeated 16 sentences from the Boston Diagnostic Aphasia Examination. Responses were transcribed orthographically and coded for accuracy (percentage accuracy; percentage Correct Information Units; Levenshtein Distance) and for temporal characteristics (preparation duration (ms); utterance duration (ms); silent pause duration (ms); speech duration (ms); dysfluency duration (ms)). The potential modulating effects of attentional control and working memory capacity were explored. Results: PCA patients showed lower overall accuracy with retained semantic content of the sentences, and lower phonological accuracy. Temporal measures revealed longer preparation and utterance duration for PCA patients compared to controls, alongside longer speech duration but comparable dysfluency duration. PCA patients also showed comparable silent pause duration to controls. Attentional control, measured using the Hayling sentence completion task, predicted accuracy of sentence repetition. Discussion: The findings suggest that sentence repetition is impaired in PCA and is characterized by phonological, response planning and execution difficulties, underpinned in part by attentional control mechanisms. The emerging profile of language impairment in PCA suggests vulnerability of similar cognitive systems to other Alzheimer's syndromes, with subtle differences in clinical presentation. [ABSTRACT FROM AUTHOR]

Background: Verbal fluency tasks are included in a broad range of aphasia assessments. It is well documented that people with aphasia (PWA) produce fewer items in these tasks. Successful performance on verbal fluency relies on the integrity of both linguistic and executive control abilities. It remains unclear if limited output in aphasia is solely due to their lexical retrieval difficulties or has a basis in their executive control abilities. Analysis techniques, such as temporal characteristics of word retrieved, clustering and switching, are better positioned to inform the debate surrounding the lexical and/or executive control contribution for success in verbal fluency. Aims: To investigate the differences in quantitative (i.e., number of correct words) and qualitative (i.e., switching, clustering and word-retrieval times) performances on animal fluency task as a function of time between PWA and healthy control speakers (CS). Methods & Procedures: Animal fluency data for 60 s were collected from 34 PWA and 34 CS, and responses were time stamped. The 60-s period was divided into four equal intervals of 15 s each (i.e., 15, 30, 45 and 60 s). The number of correct words, cluster size, number of switches, within-cluster pause and between-cluster pause were evaluated as a function of four 15-s time intervals between PWA and CS. Outcomes & Results: Compared with CS, PWA produced fewer words, had smaller cluster sizes and switched a fewer number of times. A decrease in the number of switches correlated with an increase in between-cluster pause durations. PWA showed longer within- and between-cluster pauses than CS. The two groups showed specific differences in the temporal pattern of the responses: as time evolved both PWA and CS showed decreased productivity for the number of correct words, but PWA reached the asymptote earlier in the time course than CS, neither group showed a change in cluster size, and the number of switches decreased as a function of time only for CS. Conclusions & Implications: The findings suggest that for PWA the search and retrieval process is less productive and more effortful. This is indicated by smaller cluster size, fewer switches associated with increased between-cluster pause durations, as well as overall slowed retrieval times for the words. This shows that the difficulties with verbal fluency performance in aphasia have a strong basis in their lexical retrieval processes, as well as some difficulties in the executive component of the task.

Background: Jargon aphasia is one of the most intractable forms of aphasia with limited recommendation on amelioration of associated naming difficulties and neologisms. The few naming therapy studies that exist in jargon aphasia have utilized either semantic or phonological approaches, but the results have been equivocal. Moreover, the effect of therapy on the characteristics of neologisms is less explored. Aims: This study investigates the effectiveness of a phonological naming therapy (i.e. phonological component analysis--PCA) on picture-naming abilities and on quantitative and qualitative changes in neologisms for an individual with jargon aphasia (FF). Methods & Procedures: FF showed evidence of jargon aphasia with severe naming difficulties and produced a very high proportion of neologisms. A single-subject multiple probe design across behaviours was employed to evaluate the effects of PCA therapy on the accuracy for three sets of words. In therapy, a phonological components analysis chart was used to identify five phonological components (i.e. rhymes, first sound, first sound associate, final sound and number of syllables) for each target word. Generalization effects--change in per cent accuracy and error pattern--were examined comparing pre- and post-therapy responses on the Philadelphia Naming Test, and these responses were analysed to explore the characteristics of the neologisms. The quantitative change in neologisms was measured by change in the proportion of neologisms from pre- to post-therapy and the qualitative change was indexed by the phonological overlap between target and neologism. Outcomes & Results: As a consequence of PCA therapy, FF showed a significant improvement in his ability to name the treated items. His performance in maintenance and follow-up phases remained comparable with his performance during the therapy phases. Generalization to other naming tasks did not show a change in accuracy, but distinct differences in error pattern (an increase in proportion of real word responses and a decrease in proportion of neologisms) were observed. Notably, the decrease in neologisms occurred with a corresponding trend for increase in the phonological similarity between the neologisms and the targets. Conclusions & Implications: This study demonstrated the effectiveness of a phonological therapy for improving naming abilities and reducing the amount of neologisms in an individual with severe jargon aphasia. The positive outcome of this research is encouraging, as it provides evidence for effective therapies for jargon aphasia and also emphasizes that use of the quality and quantity of errors may provide a sensitive outcome measure to determine therapy effectiveness, in particular for client groups who are difficult to treat.

Background: In addition to the well-known linguistic processing impairments in aphasia, oro-motor skills and articulatory implementation of speech segments are reported to be compromised to some degree in most types of aphasia. Aims: This study aimed to identify differences in the characteristics and coordination of lip movements in the production of a bilabial closure gesture between speech-like and non-speech tasks in individuals with aphasia and healthy control subjects. Methods & Procedures: Upper and lower lip movement data were collected for a speech-like and a non-speech task using an AG 100 EMMA system from five individuals with aphasia and five age- and gender-matched control subjects. Each task was produced at two rate conditions (normal and fast), and in a familiar and a less familiar manner. Single articulator kinematic parameters (peak velocity, amplitude, duration and cyclic spatio-temporal index) and multi-articulator coordination indices (average relative phase and variability of relative phase) were measured to characterize lip movements. Outcomes & Results: The results showed that when the two lips had similar task goals (bilabial closure) in speech-like and non-speech task, kinematic and coordination characteristics were not found to be different. However, when changes in rate were imposed on the bilabial gesture, only speech-like task showed functional adaptations, indicated by a greater decrease in amplitude and duration at fast rates. In terms of group differences, individuals with aphasia showed smaller amplitudes and longer movement durations for upper lip, higher spatio-temporal variability for both lips, and higher variability in lip coordination than the control speakers. Rate was an important factor in distinguishing the two groups, and individuals with aphasia were limited in implementing the rate changes. Conclusions & Implications: The findings support the notion of subtle but robust differences in motor control characteristics between individuals with aphasia and the control participants, even in the context of producing bilabial closing gestures for a relatively simple speech-like task. The findings also highlight the functional differences between speech-like and non-speech tasks, despite a common movement coordination goal for bilabial closure. (Contains 1 note, 4 figures, and 4 tables.)