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Background: In recent years some critical voices have been raised in regard to the significance of cognitive neuropsychology (CNP) to the study of brain and mind. Given the central role of language disorders in CNP research, it is time to consider the relevance of this research approach in aphasiology. Aims: We analyse the main points of criticism raised against the CNP research approach, evaluate the significance of this approach to the study of acquired language disorders, and make some suggestions concerning further development of the field. Main Contribution: The main points of criticism against CNP (reliance on single-case studies; single-minded hunt for dissociations; emptiness of theorising) have been important long-term concerns but do not take into account the fact that, during its history of circa four decades, the CNP approach has diversified. There are thus CNP studies that rely on case series analyses, focus on error analyses rather than mere dissociations, or employ computational modelling rather than the “boxes-and-arrows” models of the mental architecture. The CNP approach to cognition and its disorders is thus applicable to different research questions and theoretical stances, providing experimental rigour to single-case patient studies. With regard to clinical applications in aphasia diagnostics and treatment, the CNP approach provides a richer view on the strengths and weaknesses of a patient's cognitive-linguistic abilities. Conclusions: We believe that CNP case studies continue to be an important source of information for generating hypotheses and providing converging evidence for research on the mind and on the brain. However, there is a need for further research development especially in computational modelling of language processes, their impairments, and recovery. This research is expected to provide further benefit to clinical diagnostics and treatment of aphasia. [ABSTRACT FROM AUTHOR]

Background: The study of novel word learning in aphasia can shed light on the functionality of patients' learning mechanisms and potentially help in treatment planning. Previous studies have indicated that persons with aphasia are able to learn some new vocabulary. However, these learning outcomes appear short-lived and evidence for the ability to use the newly learned words in the long term is lacking. Aims: Participants with aphasia and matched controls underwent short training where they were taught to name novel objects with novel names. We studied the participants' word learning and particularly their long-term maintenance. We also examined whether the language and verbal short-term memory impairments of the participants with aphasia related to their ability to acquire and maintain phonological and semantic information on novel words. Methods & Procedures: Two participants with nonfluent aphasia, LL and AR, and two matched controls took part in the experiment. They were taught to name 20 unfamiliar objects by repeating the names in the presence of the object picture. Half of the items carried a definition that was used to probe incidental semantic learning. There were four training sessions, a post-training test, and follow-up tests up to 6 months post-training. Learning measures included recognition of the trained objects, as well as spontaneous and cued recall in visual confrontation naming. Incidental semantic learning was measured by spontaneous recall of the definitions. Outcomes & Results: Combining spontaneous and phonologically cued responses, LL acquired 70% and AR 55% of the novel words. With phonological cueing, LL named 50% of the items correctly up to 6 months post-training (vs 95–100% for the controls) and AR 25% up to 8 weeks post-training. AR's lexical-semantic processing, pseudoword repetition and verbal short-term capacity were inferior to those of LL. In line with this, AR learned fewer words and showed more decline in recognition memory for the trained items, and weaker recall of the semantic definitions. Conclusions: Our results support previous findings that people with aphasia can learn to name novel items. More importantly, the results show for the first time that, with phonological cueing, an individual with aphasia can maintain some of this learning up to 6 months post-training. Moreover the results provide further evidence for the significance of the functional status of lexical-semantic processing on word learning success. [ABSTRACT FROM AUTHOR]

Background: Language performance in aphasia can vary depending on several variables such as stimulus characteristics and task demands. This study focuses on the degree of verbal working memory (WM) load inherent in the language task and how this variable affects language performance by individuals with aphasia. Aims: The first aim was to identify the effects of increased verbal WM load on the performance of judgements of semantic similarity (synonymy) and phonological similarity (rhyming). The second aim was to determine if any of the following abilities could modulate the verbal WM load effect: semantic or phonological access, semantic or phonological short-term memory (STM), and any of the following executive processing abilities: inhibition, verbal WM updating, and set shifting. Method & Procedures: A total of 31 individuals with aphasia and 11 controls participated in this study. They were administered a synonymy judgement task and a rhyming judgement task under high and low verbal WM load conditions that were compared to each other. In a second set of analyses multiple regression was used to identify which factors (as noted above) modulated the verbal WM load effect. Outcomes & Results: For participants with aphasia, increased verbal WM load significantly reduced accuracy of performance on synonymy and rhyming judgements. Better performance in the low verbal WM load conditions was evident even after correcting for chance. The synonymy task included concrete and abstract word triplets. When these were examined separately the verbal WM load effect was significant for the abstract words, but not the concrete words. The same pattern was observed in the performance of the control participants. Additionally, the second set of analyses revealed that semantic STM and one executive function, inhibition ability, emerged as the strongest predictors of the verbal WM load effect in these judgement tasks for individuals with aphasia. Conclusions: The results of this study have important implications for diagnosis and treatment of aphasia. As the roles of verbal STM capacity, executive functions and verbal WM load in language processing are better understood, measurements of these variables can be incorporated into our diagnostic protocols. Moreover, if cognitive abilities such as STM and executive functions support language processing and their impairment adversely affects language function, treating them directly in the context of language tasks should translate into improved language function. [ABSTRACT FROM AUTHOR]

Background: Novel word learning of persons with aphasia is little studied, even though a better understanding of learning processes would inform development of effective treatment strategies. Recent evidence suggests some remaining verbal learning capacity in persons with aphasia. Long-term maintenance of newly learned active vocabulary has not been reported previously in persons with aphasia. Aims: To explore learning and long-term maintenance of novel words in persons with aphasia. Methods & Procedures: Two English-speaking males with chronic anomic aphasia and two age-matched controls were taught novel names of 20 unfamiliar objects. Half of the words were taught with semantic information (definition) and half without. Participants were instructed to learn the names. The experiment included four training sessions, one post-training test and four follow-up tests administered 1 week, 4 weeks, 8 weeks, and 6 months post-training. We tested explicit learning of the new names through visual confrontation naming. In addition, incidental learning of semantic information was probed over the follow-up period. Outcomes & Results: The two participants with aphasia learned 6-8 of the 20 novel names during the training. However, this new vocabulary dissipated during the 6-month follow-up. As expected, the controls showed better performance both in acquisition and in maintenance of the new vocabulary over the follow-up period. As regards the accuracy of semantic information, the aphasic participant with semantic impairment demonstrated worse incidental learning of semantic information than controls and the participant with intact lexical semantics. Conclusions: Some new vocabulary can be acquired even in chronic aphasia but the ability to spontaneously retrieve the newly learned words gradually dissipates over the weeks following learning. Our results also indicate an interaction between the level of lexical-semantic processing skills and incidental learning of new lexical-semantic knowledge in aphasia. [ABSTRACT FROM AUTHOR]

Background: We present an anomia treatment study using a modified contextual priming (CP) technique for two anomic participants. The reason for the modification attempt is that the most recent studies have indicated that the CP procedure is less effective in the case of impairment to lexical-semantic processes than in the case of phonological deficits (see Martin, Fink, & Laine, 2004a; Martin, Fink, Laine, & Ayala, 2004b; Renvall, Laine, & Martin, 2005). Aims: Our aim is to study the within- and post-treatment effects of a modified CP procedure and especially whether additional semantic tasks can increase benefits from the CP treatment. Methods & Procedures: The treatment was conducted for two participants with acquired anomia: LV has primarily a semantic component underlying her anomia, while JP suffers primarily from a phoneme-sequencing deficit. The CP procedure encompassed repeated cycles of spontaneous naming attempts and repetition of target names using arrays of multiple pictures where the targets were either semantically related or unrelated. Our modification was to add picture-to-word matching and phonological "rhyming syllable identification" with the targets to the training sequence. The treatment was carried out in a single-subject multiple-baseline design consisting of several baseline measurements, treatment sessions along with within-treatment measurements, and a post-treatment measurement 1.5 months later. Outcomes & Results: Both participants showed short-term facilitation of naming target items in all treatment conditions. For LV, post-treatment improvement of naming was statistically significant in the semantic condition irrespective of additional task type, even though the improvement was strongest when the semantic condition was coupled with the additional semantic tasks. In the case of JP, post-treatment improvement was observed in the semantic condition coupled with additional semantic tasks, and in the unrelated condition with both semantic and phonological tasks. No strong evidence of generalisation to untreated items was observed for either of the participants. Conclusions: The modified CP procedure can provide longer-term improvement of naming target items than the CP training without additional tasks in the face of a lexical-semantic deficit. With lexical-semantic disturbance, the semantic context provided the best results. However, the nature of the additional tasks (semantic vs phonological) appeared to be less important for the treatment of target naming. [ABSTRACT FROM AUTHOR]

Background: Repetition priming is often a component of treatments for word-finding disorders. It can facilitate or interfere with naming success depending on a number of factors. Here we investigate the effectiveness of massed priming coupled with semantic or phonological context as a treatment for naming impairments arising from semantic and phono- logical deficits. Aims: We aimed to determine whether (1) this procedure, used previously in a short-term facilitation study, would effectively improve word retrieval in a treatment study, and (2) the pattern of facilitation or interference observed in the facilitation study would carry over to the treatment programme. Methods & Procedures: We used a single subject multiple baseline design. There were two participants: LP with a phonological encoding deficit and AS with both semantic and phonological deficits, Treatment involved identifying and repeating the names of words that were related semantically or phonologically, or unrelated. Pm and post measures of naming were used to assess overall effectiveness of the treatment. Acquisition, maintenance, and generalisation were measured with baseline tests at the start of each session. Correct responses and errors on within-training naming probes were used to measure sensitivity to priming in a particular context. Outcomes & Results: LP benefited from this procedure regardless of the training context AS showed interference in the semantic context during training and only modest short-term gains. These outcomes were predicted by theft performance on an earlier facilitation study. Conclusions: Contextual repetition priming has different effects on naming and these differences appear to be related to the context of training (semantic or phonological) and the primary source of an individual's naming impairment (semantic or phonological). This procedure is most effective when semantic processing of words is relatively spared. [ABSTRACT FROM AUTHOR]