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The current study examines the hypothesis that differential aphasia may be due to a problem with language control rather than with language-specific impairment and how this is related to non-linguistic cognitive control abilities. To this end, we report a case study of an L2 dominant French-English bilingual aphasia patient with larger impairments in French than in English. We assessed cross-language interactions using cognates in three lexical decision (LD) tasks, and non-linguistic cognitive control with a flanker task. We also examined functional connectivity between brain regions crucial for language control and language processing. We observed the preservation of cognate effects in a generalized lexical decision task requiring little language control, which indicates intact functionality (and cross-lingual interactivity) of lexical representations. On the other hand, we found diminished linguistic as well as non-linguistic control abilities, suggesting a domain general control impairment. Resting-state functional Magnetic Resonance Imaging (rs-fMRI) analysis revealed altered connectivity between the patient's language control and processing network, consistent with the behavioral data. Altogether, these results are in line with the hypothesis that differential aphasia may originate from general cognitive control difficulties.

Stroke in the language dominant hemisphere is the most frequent cause of aphasia. In the course of post-stroke aphasia different mechanisms can contribute to the recovery of language: recovery from ischemia, compensatory rerouting of language modalities and neuroplasticity occur at different time scales after the initial injury. These mechanisms may occur spontaneously or may be induced or influenced by various therapeutic interventions. This report contains a systematic review of the literature concerning the debated role of the right hemisphere in the recovery from stroke-related aphasia. The existing literature was approached using the PICOS principle and well-established inclusion and exclusion criteria. Although many gaps remain in the knowledge on the role of the right hemisphere, there is some evidence of a facilitation of spontaneous language recovery in the acute and subacute phase. In the subacute and chronic phase, the right hemisphere homologous language areas, along with memory and attention-related areas, facilitate treatment related improvement. In contrast, in therapy-free periods in the chronic stage, the right hemisphere no longer contributes to language recovery or may even be inhibitory. Injury-, language- and therapy-related variables impact on the role of the right hemisphere in aphasia recovery.

Summary Introduction Facial allotransplantation constitutes a reconstructive option after extensive damage to facial structures. Functional recovery has been reported but remains an issue. Case report – Methods A patient underwent facial allotransplantation after a ballistic injury with extensive facial tissue damage. Speech motor function was sequentially assessed clinically, along with repeated electromyography of lip movements during a follow-up of 3 years. Results Facial nerve recovery could be demonstrated within the first month, followed by a gradual increase in electromyographic amplitude and decrease in reaction times. These were accompanied by gradual improvement of clinical assessments. Conclusions Axonal recovery starts early after transplantation. Electromyographic testing is sensitive in demonstrating this early recovery, which ultimately results in clinical improvements.

Motor speech requires numerous neural computations including feedforward and feedback control mechanisms. A reduction of auditory or somatosensory feedback may be implicated in disorders of speech, as predicted by various models of speech control. In this paper the effects of reduced somatosensory feedback on articulation and intelligibility of individual phonemes was evaluated by using topical anesthesia of orobuccal structures in 24 healthy subjects. The evaluation was done using a combination of perceptual intelligibility estimation of consonants and vowels and acoustic analysis of motor speech. A significantly reduced intelligibility was found, with a major impact on consonant formation. Acoustic analysis demonstrated disturbed diadochokinesis. These results underscore the clinical importance of somatosensory feedback in speech control. The interpretation of these findings in the context of speech control models, neuro-anatomy and clinical neurology may have implications for subtyping of dysarthria.

Objective In contrast to the wealth of studies on quality of life (QoL) in patients with Parkinson's disease, the number of reports on QoL in caregivers, especially partners as primary caregivers, is fairly limited. In this report we wanted to investigate if patients and caregiving partners are able to reliably estimate each other's present and former QoL. Methods We used a visual analogue scale in order to obtain the patients’ and their partners’ scores of present and former QoL. Moreover we studied correlations of these mutual estimates with demographic variables and measures of patient dependency. Results As expected both patients and partners considered their QoL as decreased when compared to former QoL. Interestingly both patients and partners were able to reliably estimate each other's QoL. Patients judged their own former QoL and that of their partner as lower as did their partners. All QoL measures were significantly correlated to measures of mental state and patient dependency. There was a negative correlation with increasing age but not with disease duration. Conclusion These results indicate the validity of using proxy information by a caregiving partner in estimations of QoL.

Purpose: Most studies on treatment of prosody in individuals with dysarthria due to Parkinson's disease are based on intensive treatment of loudness. The present study investigates the effect of intensive treatment of speech rate and intonation on the intelligibility of individuals with dysarthria due to Parkinson's disease. Methods: A one group pretest posttest design was used to compare intelligibility, speech rate, and intonation before and after treatment. Participants included eleven Dutch-speaking individuals with predominantly moderate dysarthria due to Parkinson's disease, who received five one-hour treatment sessions per week during three weeks. Treatment focused on lowering speech rate and magnifying the phrase final intonation contrast between statements and questions. Intelligibility was perceptually assessed using a standardized sentence intelligibility test. Speech rate was automatically assessed during the sentence intelligibility test as well as during a passage reading task and a storytelling task. Intonation was perceptually assessed using a sentence reading task and a sentence repetition task, and also acoustically analyzed in terms of maximum fundamental frequency. Results: After treatment, there was a significant improvement of sentence intelligibility (effect size .83), a significant increase of pause frequency during the passage reading task, a significant improvement of correct listener identification of statements and questions, and a significant increase of the maximum fundamental frequency in the final syllable of questions during both intonation tasks. Conclusion: The findings suggest that participants were more intelligible and more able to manipulate pause frequency and statement-question intonation after treatment. However, the relationship between the change in intelligibility on the one hand and the changes in speech rate and intonation on the other hand is not yet fully understood. Results are nuanced in the light of the operated research design. Learning outcomes: The reader will be able to: (1) describe the effect of intensive speech rate and intonation treatment on intelligibility of speakers with dysarthria due to PD, (2) describe the effect of intensive speech rate treatment on rate manipulation by speakers with dysarthria due to PD, and (3) describe the effect of intensive intonation treatment on manipulation of the phrase final intonation contrast between statements and questions by speakers with dysarthria due to PD. (C) 2015 Elsevier Inc. All rights reserved.

Deep brain stimulation (DBS) of the subthalamic nucleus (STN) has become an established therapeutic option for advanced Parkinson's disease (PD). In this study, the effects of unilateral and bilateral STN stimulation on spontaneous language production are explored, by comparing linguistic performance in different stimulation conditions with normative data of healthy subjects. Language samples of ten PD patients with DBS of the STN were obtained in four stimulation conditions: bilateral stimulation on, bilateral stimulation off, stimulation of the left STN only and stimulation of the right STN only. The spontaneous language production differed from the normative data in all four stimulation conditions. Especially morphosyntactic elements of spontaneous language production were altered. Despite these linguistic differences with normal controls no significant differences between stimulation conditions were found. These results emphasize that the effects of STN stimulation on spontaneous language production reflect a complex interplay of multiple factors.

Patients with Parkinson’s Disease (PD) evidence an impairment of implicit language processing, specifically for phonology, morphology and syntax. The current manuscript reports an electrophysiological investigation of semantic comprehension of action words in PD. In seven patients with advanced PD, we investigated the dopaminergic effects on action-word comprehension by means of event-related potentials. The patients were asked to silently read a randomized series of verbs, consisting of hand action and non-action verbs. Using LORETA-analysis, the current densities in ten brain areas of interest were studied over a predefined time window from 150 to 260 ms after word onset. Higher current densities were found after levodopa administration. In 5/7 patients a temporal increase in current density was found in these areas between 200 and 230 ms after word onset. In 1 of these 5 patients, this occurred only during the on-evaluation. Moreover, our results suggest a laterality of these effects, corresponding with the laterality of clinical motor signs. These results are discussed in a broad context of neuromodulatory influence of dopamine on semantic activation and lateralized physiological changes in PD.

In this manuscript we report speech dysfluencies in two patients with the syndrome of “pure akinesia with gait freezing”. The severity, the nature and the distribution of the dysfluencies were analyzed, as well as the effects of delayed auditory feedback. Word-initial repetitions were the most frequent type of dysfluency, followed by prolongations. Blocks were not found. The effect of delayed auditory feedback differed between both cases. These results allow formulating the hypothesis of a double pathophysiological mechanism underlying speech dysfluencies in this disorder.

In this report, we have analyzed the effects of left and right STN stimulation separately on different aspects of speech. Significant differences were found between left and right stimulation. It appears that selective left-sided stimulation has a profoundly negative effect on prosody, articulation and hence intelligibility. Right-sided stimulation does not display this side-effect. There is no significant difference in speech characteristics between bilateral stimulation on and off. We suggest that a balanced tuning of bilateral basal ganglia networks is necessary for speech, and that the left circuit is probably dominant.

We describe the outcome of deep brain stimulation of the internal pallidum in a 57-year old patient with multiple system atrophy. Although the prominent dystonic features of this patient were markedly attenuated post-operatively, the outcome was to be considered unfavourable. There was a severe increase in akinesia resulting in overall decrease of mobility in limbs as well as in the face. As a result, the patient was anarthric and displayed dysphagia. A laterality effect of stimulation on oro-facial movements was demonstrated. The patient died 7 months post-operatively. This report adds to the growing consensus that multiple system atrophy patients are unsuitable candidates for deep brain stimulation.