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Purpose: Repetitive transcranial magnetic stimulation (rTMS) can enhance aphasia recovery. Most studies have used inhibitory stimulation targeting the right inferior frontal gyrus. However, the motor cortex, observed to contribute to the prediction of aphasia recovery, is involved in word production and could be an appropriate target for rTMS. We aimed to observe behavioral changes in a picture naming task induced by inhibitory rTMS targeting the right motor cortex of the lips in people with poststroke aphasia. Method: Using a single-case experimental design, we included three participants with chronic poststroke aphasia who had phonological deficits. Each participant performed a verbal picture naming task 3 times a week for 2, 3, or 4 weeks (pseudorandom across participants) to establish a baseline naming ability for each participant. These were not therapy sessions, and no feedback was provided. Then, each participant received the intervention, inhibitory continuous theta burst stimulation targeting the right motor cortex of the lips, 3 times a week for 2 weeks. Naming testing continued 3 times a week, for these latter 2 weeks. No therapy was performed at any time during the study. Results: Visual analysis of the graphs showed a positive effect of rTMS for P2 and P3 on picture naming accuracy and a tendency toward improvement for P1. Statistical analysis showed an improvement after rTMS for P1 (τ = 0.544, p = .013, SETau = 0.288) and P2 (τ = 0.708, p = .001, SETau = 0.235). For P3, even if the intervention allowed some improvement, this was statistically nonsignificant due to a learning effect during the baseline naming testing, which lasted the longest, 4 weeks. Regarding specific language features, phonological errors significantly decreased in all patients. Conclusions: The motor cortex of the lips could be an appropriate target for rTMS to improve naming in people with poststroke aphasia suffering from a phonological deficit. This suggests the possibility to individualize the target for rTMS, according to the patient's linguistic impairment. [ABSTRACT FROM AUTHOR]

Background: Utterance production is affected under dual-task conditions, but so far studies have shown an impact either on lexical or on phonological processes, but not on both simultaneously. Aims: In the present study, we aimed at investigating how interference on lexical and phonological encoding is modulated by the timing of the concurrent task and by the attentional requirement (divided vs focused attention). Methods: Participants with aphasia (PWA) underwent a picture naming task and an auditory detection task, with auditory stimuli presented at different stimulus onset asynchronies (SOAs). The dual-task was performed under divided (Experiment 1) and focused attention (Experiment 2). Outcome & Results: Omission errors increased under dual-task at early SOA only in Experiment 1 while phonological errors increased at later SOAs in both experiments. Conclusion: These patterns of errors indicate that lexical and phonological processes are impacted under dual-task conditions, giving rise to an increase of specific types of errors at specific SOAs. They also show that very mild anomia may be more severe when assessed under dual-task conditions. [ABSTRACT FROM AUTHOR]

Background: The question of how much speakers plan ahead before they start articulating their message is essential to understand how fluency is ensured during speech production. This question has been largely investigated in healthy speakers. Surprisingly, this remains unexplored for brain-damaged speakers, even though a reduced span of encoding might account for the fact that those impaired speakers often produce scattered speech. Aims: In this study, we examine whether the span of encoding is reduced in some left hemisphere brain-damaged speakers by taking advantage of two linguistic phenomena which provide an insight into ahead phonological planning. Methods and procedures: First, we elicit the production of French sequences involving obligatoryliaisons(e.g., /mõ/ and /ami/ produced /mõ.nami/), for which the correct production requires ahead planning, at least up to the first phoneme of the following word of the utterance. Second, we use tongue-twister-like sequences in order to elicit contextual phonological errors, as phoneme anticipation errors (e.g., bureau vert—green desk—produced /vyRo.vER/) suggest that the speaker has planned ahead before articulating. If brain-damaged speakers do present a reduced span of encoding, they should both produce a high rate of liaison consonant omissions and a low rate of anticipation contextual phonological errors. Outcome and results: The results on a group of 13 speakers with aphasia and/or apraxia of speech overall show few contextual (syntagmatic) errors despite a high rate of segmental errors, whereas the majority of phonological errors produced on the same utterances by healthy speakers were syntagmatic. The speech/language impaired participants also presented a high rate of obligatory liaison consonants omission. Crucially, a negative correlation was observed between the rate of phoneme anticipation errors and the rate of liaison consonant omission. Conclusion: These results suggest that some brain-damaged speakers present a span of phonological encoding limited to single words and that the use of inter-word sandhi phenomena, such as French liaison and the analysis of phoneme anticipation errors, are valid linguistic tools to inform on the span of encoding. [ABSTRACT FROM PUBLISHER]

Post-stroke aphasia recovery is multifactorial and results from a complex equation between four types of interrelated factors : a) neurobiological factors, such as lesion size and location, but also to some extent the neural reserve in undamaged brain areas ; b) behavioral factors, mostly related to the initial severity of stroke symptoms ; c) personal factors, such as age and gender, that remain however poorly investigated and debated and d) therapeutic factors, related to medical endovascular interventions and to speech and language therapy. Future studies are crucial to determine more precisely the weight and the interaction of these factors in the recovery process of post-stroke aphasia., Competing Interests: Les auteurs n’ont déclaré aucun conflit d’intérêts en relation avec cet article.