Dementia with aphasia and mirror phenomenon: examination of the mechanism using neuroimaging and neuropsychological findings: a case report.

BACKGROUND: Aphasia often appears in persons living with dementia; however, aphasia and the mirror phenomenon are rarely present at the same time. CASE PRESENTATION: Here, we report a case of fluent conversation with a person in a mirror or a magazine, and examine the underlying mechanism using brain imaging and neuropsychological findings. We found that the appearance of the mirror phenomenon may be associated with a visuospatial dysfunction caused by a decreased function of the posterior region of the right temporal and parietal lobe. Moreover, active talking to a person in a mirror or a person in a magazine could be associated with disinhibition caused by a decline in bilateral frontal lobe function. CONCLUSIONS: This case represents a very valuable and interesting presentation because it is the first report of a long-term follow-up of the course of dementia using neurological imaging, and of the neuropsychological analysis of the mechanism of conversation with a mirror image combined with aphasia.

Retraining speech production and fluency in non-fluent/agrammatic primary progressive aphasia.

The non-fluent/agrammatic variant of primary progressive aphasia (nfvPPA) presents with a gradual decline in grammar and motor speech resulting from selective degeneration of speech-language regions in the brain. There has been considerable progress in identifying treatment approaches to remediate language deficits in other primary progressive aphasia variants; however, interventions for the core deficits in nfvPPA have yet to be systematically investigated. Further, the neural mechanisms that support behavioural restitution in the context of neurodegeneration are not well understood. We examined the immediate and long-term benefits of video implemented script training for aphasia (VISTA) in 10 individuals with nfvPPA. The treatment approach involved repeated rehearsal of individualized scripts via structured treatment with a clinician as well as intensive home practice with an audiovisual model using 'speech entrainment'. We evaluated accuracy of script production as well as overall intelligibility and grammaticality for trained and untrained scripts. These measures and standardized test scores were collected at post-treatment and 3-, 6-, and 12-month follow-up visits. Treatment resulted in significant improvement in production of correct, intelligible scripted words for trained topics, a reduction in grammatical errors for trained topics, and an overall increase in intelligibility for trained as well as untrained topics at post-treatment. Follow-up testing revealed maintenance of gains for trained scripts up to 1 year post-treatment on the primary outcome measure. Performance on untrained scripts and standardized tests remained relatively stable during the follow-up period, indicating that treatment helped to stabilize speech and language despite disease progression. To identify neural predictors of responsiveness to intervention, we examined treatment effect sizes relative to grey matter volumes in regions of interest derived from a previously identified speech production network. Regions of significant atrophy within this network included bilateral inferior frontal cortices and supplementary motor area as well as left striatum. Volumes in a left middle/inferior temporal region of interest were significantly correlated with the magnitude of treatment effects. This region, which was relatively spared anatomically in nfvPPA patients, has been implicated in syntactic production as well as visuo-motor facilitation of speech. This is the first group study to document the benefits of behavioural intervention that targets both linguistic and motoric deficits in nfvPPA. Findings indicate that behavioural intervention may result in lasting and generalized improvement of communicative function in individuals with neurodegenerative disease and that the integrity of spared regions within the speech-language network may be an important predictor of treatment response.

Auditory training changes temporal lobe connectivity in 'Wernicke's aphasia': a randomised trial.

INTRODUCTION: Aphasia is one of the most disabling sequelae after stroke, occurring in 25%-40% of stroke survivors. However, there remains a lack of good evidence for the efficacy or mechanisms of speech comprehension rehabilitation. TRIAL DESIGN: This within-subjects trial tested two concurrent interventions in 20 patients with chronic aphasia with speech comprehension impairment following left hemisphere stroke: (1) phonological training using 'Earobics' software and (2) a pharmacological intervention using donepezil, an acetylcholinesterase inhibitor. Donepezil was tested in a double-blind, placebo-controlled, cross-over design using block randomisation with bias minimisation. METHODS: The primary outcome measure was speech comprehension score on the comprehensive aphasia test. Magnetoencephalography (MEG) with an established index of auditory perception, the mismatch negativity response, tested whether the therapies altered effective connectivity at the lower (primary) or higher (secondary) level of the auditory network. RESULTS: Phonological training improved speech comprehension abilities and was particularly effective for patients with severe deficits. No major adverse effects of donepezil were observed, but it had an unpredicted negative effect on speech comprehension. The MEG analysis demonstrated that phonological training increased synaptic gain in the left superior temporal gyrus (STG). Patients with more severe speech comprehension impairments also showed strengthening of bidirectional connections between the left and right STG. CONCLUSIONS: Phonological training resulted in a small but significant improvement in speech comprehension, whereas donepezil had a negative effect. The connectivity results indicated that training reshaped higher order phonological representations in the left STG and (in more severe patients) induced stronger interhemispheric transfer of information between higher levels of auditory cortex.Clinical trial registrationThis trial was registered with EudraCT (2005-004215-30, https://eudract.ema.europa.eu/) and ISRCTN (68939136, http://www.isrctn.com/).

Current Controversies on Wernicke's Area and its Role in Language.

PURPOSE OF REVIEW: The aim of the study is to assess historical anatomical and functional definitions of Wernicke's area in light of modern lesion and neuroimaging data. RECENT FINDINGS: "Wernicke's area" has become an anatomical label usually applied to the left posterior superior temporal gyrus and adjacent supramarginal gyrus. Recent evidence shows that this region is not critical for speech perception or for word comprehension. Rather, it supports retrieval of phonological forms (mental representations of phoneme sequences), which are used for speech output and short-term memory tasks. Focal damage to this region produces phonemic paraphasia without impairing word comprehension, i.e., conduction aphasia. Neuroimaging studies in recent decades provide evidence for a widely distributed temporal, parietal, and frontal network supporting language comprehension, which does not include the anatomically defined Wernicke area. The term Wernicke's area, if used at all, should not be used to refer to a zone critical for speech comprehension.

Varieties of semantic 'access' deficit in Wernicke's aphasia and semantic aphasia.

Comprehension deficits are common in stroke aphasia, including in cases with (i) semantic aphasia, characterized by poor executive control of semantic processing across verbal and non-verbal modalities; and (ii) Wernicke's aphasia, associated with poor auditory-verbal comprehension and repetition, plus fluent speech with jargon. However, the varieties of these comprehension problems, and their underlying causes, are not well understood. Both patient groups exhibit some type of semantic 'access' deficit, as opposed to the 'storage' deficits observed in semantic dementia. Nevertheless, existing descriptions suggest that these patients might have different varieties of 'access' impairment-related to difficulty resolving competition (in semantic aphasia) versus initial activation of concepts from sensory inputs (in Wernicke's aphasia). We used a case series design to compare patients with Wernicke's aphasia and those with semantic aphasia on Warrington's paradigmatic assessment of semantic 'access' deficits. In these verbal and non-verbal matching tasks, a small set of semantically-related items are repeatedly presented over several cycles so that the target on one trial becomes a distractor on another (building up interference and eliciting semantic 'blocking' effects). Patients with Wernicke's aphasia and semantic aphasia were distinguished according to lesion location in the temporal cortex, but in each group, some individuals had additional prefrontal damage. Both of these aspects of lesion variability-one that mapped onto classical 'syndromes' and one that did not-predicted aspects of the semantic 'access' deficit. Both semantic aphasia and Wernicke's aphasia cases showed multimodal semantic impairment, although as expected, the Wernicke's aphasia group showed greater deficits on auditory-verbal than picture judgements. Distribution of damage in the temporal lobe was crucial for predicting the initially 'beneficial' effects of stimulus repetition: cases with Wernicke's aphasia showed initial improvement with repetition of words and pictures, while in semantic aphasia, semantic access was initially good but declined in the face of competition from previous targets. Prefrontal damage predicted the 'harmful' effects of repetition: the ability to reselect both word and picture targets in the face of mounting competition was linked to left prefrontal damage in both groups. Therefore, patients with semantic aphasia and Wernicke's aphasia have partially distinct impairment of semantic 'access' but, across these syndromes, prefrontal lesions produce declining comprehension with repetition in both verbal and non-verbal tasks.

The anterior temporal lobes support residual comprehension in Wernicke's aphasia.

Wernicke's aphasia occurs after a stroke to classical language comprehension regions in the left temporoparietal cortex. Consequently, auditory-verbal comprehension is significantly impaired in Wernicke's aphasia but the capacity to comprehend visually presented materials (written words and pictures) is partially spared. This study used functional magnetic resonance imaging to investigate the neural basis of written word and picture semantic processing in Wernicke's aphasia, with the wider aim of examining how the semantic system is altered after damage to the classical comprehension regions. Twelve participants with chronic Wernicke's aphasia and 12 control participants performed semantic animate-inanimate judgements and a visual height judgement baseline task. Whole brain and region of interest analysis in Wernicke's aphasia and control participants found that semantic judgements were underpinned by activation in the ventral and anterior temporal lobes bilaterally. The Wernicke's aphasia group displayed an 'over-activation' in comparison with control participants, indicating that anterior temporal lobe regions become increasingly influential following reduction in posterior semantic resources. Semantic processing of written words in Wernicke's aphasia was additionally supported by recruitment of the right anterior superior temporal lobe, a region previously associated with recovery from auditory-verbal comprehension impairments. Overall, the results provide support for models in which the anterior temporal lobes are crucial for multimodal semantic processing and that these regions may be accessed without support from classic posterior comprehension regions.

"My Mind Is Doing It All": No "Brake" to Stop Speech Generation in Jargon Aphasia.

OBJECTIVE: To study whether pressure of speech in jargon aphasia arises out of disturbances to core language or executive processes, or at the intersection of conceptual preparation. BACKGROUND: Conceptual preparation mechanisms for speech have not been well studied. Several mechanisms have been proposed for jargon aphasia, a fluent, well-articulated, logorrheic propositional speech that is almost incomprehensible. METHODS: We studied the vast quantity of jargon speech produced by patient J.A., who had suffered an infarct after the clipping of a middle cerebral artery aneurysm. We gave J.A. baseline cognitive tests and experimental word- and sentence-generation tasks that we had designed for patients with dynamic aphasia, a severely reduced but otherwise fairly normal propositional speech thought to result from deficits in conceptual preparation. RESULTS: J.A. had cognitive dysfunction, including executive difficulties, and a language profile characterized by poor repetition and naming in the context of relatively intact single-word comprehension. J.A.'s spontaneous speech was fluent but jargon. He had no difficulty generating sentences; in contrast to dynamic aphasia, his sentences were largely meaningless and not significantly affected by stimulus constraint level. CONCLUSIONS: This patient with jargon aphasia highlights that voluminous speech output can arise from disturbances of both language and executive functions. Our previous studies have identified three conceptual preparation mechanisms for speech: generation of novel thoughts, their sequencing, and selection. This study raises the possibility that a "brake" to stop message generation may be a fourth conceptual preparation mechanism behind the pressure of speech characteristic of jargon aphasia.

Impalement brain injury from steel rod causing injury to jugular bulb: case report and review of the literature.

BACKGROUND: The management of impalement penetrating brain injuries (IPBI) from non-missile objects is extremely challenging, especially when vascular structures are involved. Cerebral angiography is a crucial tool in initial evaluation to assess for vascular injury as standard non-invasive imaging modalities are limited by foreign body artifact, especially for metallic objects. CASE STUDY: This study reports a case of an IPBI caused by a segment of steel rebar resulting in injury to the left jugular bulb and posterior temporal lobe. It describes the initial presentation, radiology, management and outcome in this patient and reviews the literature of similar injuries.

Visual Attention to Semantic and Orthographic Associations in Fluent Aphasia: Evidence from Eye-Tracking.

We examined the allocation of visual attention in an association task by both neurotypical participants (n = 11) and adults with fluent aphasia (n = 12). Participants were presented with a picture (e.g., a basket) followed by a semantically related association (i.e., "strawberry") and an orthographically related association (i.e., "b," the first letter of "basket"). An eye tracker recorded their eye movements for three areas of interest (AOI): the picture, the semantic associate, and the orthographic associate, over 1396 observations. Results showed that both neurotypical participants and participants with aphasia looked longer at the semantic associate than at the picture, and this difference was more pronounced for neurotypicals than for people with aphasia (PWA). Neurotypicals also looked longer than the PWA group at the orthographic associate than at the prior picture. Regarding eye fixation counts, both participant groups looked more frequently at the semantic associate than at either the picture or the orthographic associate. Notably, this pattern was more pronounced among neurotypical participants than PWA. Our findings emphasize the importance of semantic associations in fluent aphasia and suggest a potential rehabilitative approach in speech and language therapy.

[FMRI-study of speech perception impairment in post-stroke patients with sensory aphasia].

The aim of the study was to find neurophysiological correlates of the primary stage impairment of speech perception, namely phonemic discrimination, in patients with sensory aphasia after acute ischemic stroke in the left hemisphere by noninvasive method of fMRI. For this purpose we registered the fMRI-equivalent of mismatch negativity (MMN) in response to the speech phonemes--syllables "ba" and "pa" in odd-ball paradigm in 20 healthy subjects and 23 patients with post-stroke sensory aphasia. In healthy subjects active brain areas depending from the MMN contrast were observed in the superior temporal and inferior frontal gyri in the right and left hemispheres. In the group of patients there was a significant activation of the auditory cortex in the right hemisphere only, and this activation was less in a volume and intensity than in healthy subjects and correlated to the degree of preservation of speech. Thus, the method of recording fMRI equivalent of MMN is sensitive to study the speech perception impairment.

Effects of mindfulness meditation on three individuals with aphasia.

BACKGROUND: There is evidence to suggest that people with aphasia (PWA) may have deficits in attention stemming from the inefficient allocation of resources. The inaccurate perception of task demand, or sense of effort, may underlie the misallocation of the available attention resources. Given the lack of treatment options for improving attention in aphasia, Mindfulness Meditation, shown to improve attention in neurologically intact individuals, may prove effective in increasing attention in PWA. AIMS: The purpose of the present study was to determine if Mindfulness Meditation improves divided attention or language in PWA and if it affects the overall sense of effort. METHODS & PROCEDURES: A multiple baseline single-subject design was used to determine the effects of Mindfulness Meditation on divided attention for three PWA. Divided attention was measured using a non-linguistic divided attention task. Visual inspection of the data was used to determine changes in performance (sense of effort, reaction time and accuracy, language) over time. OUTCOMES & RESULTS: High performance observed on the attention measures suggests that PWA have varying degrees of attentional impairment that may surface when certain demands are presented. There were no observable changes in the performance on the sense of effort or language measures; however, measures of reaction time may indicate Mindfulness Meditation improved efficiency of task completion. CONCLUSIONS & IMPLICATIONS: All three participants reported that Mindfulness Meditation was easy to learn and carry out on a daily basis, and reported feeling more 'relaxed' and 'peaceful' after Mindfulness Meditation training than before. With the knowledge that PWA can learn meditative practices, and with such successful findings in neurologically intact individuals, it is important to continue evaluating the benefits of Mindfulness Meditation in PWA.

Compound nouns in spoken language production by speakers with aphasia compared to neurologically healthy speakers: an exploratory study.

Compounds are words that are made up of at least two other words (lexemes), featuring lexical and syntactic characteristics and thus particularly interesting for the study of language processing. Most studies of compounds and language processing have been based on data from experimental single word production and comprehension tasks. To enhance the ecological validity of morphological processing research, data from other contexts, such as discourse production, need to be considered. This study investigates the production of nominal compounds in semi-spontaneous spoken texts by a group of speakers with fluent types of aphasia compared to a group of neurologically healthy speakers. The speakers with aphasia produce significantly fewer nominal compound types in their texts than the non-aphasic speakers, and the compounds they produce exhibit fewer different types of semantic relations than the compounds produced by the non-aphasic speakers. The results are discussed in relation to theories of language processing.

Role of the corpus callosum in speech comprehension: interfacing syntax and prosody.

The role of the corpus callosum (CC) in the interhemispheric interaction of prosodic and syntactic information during speech comprehension was investigated in patients with lesions in the CC, and in healthy controls. The event-related brain potential experiment examined the effect of prosodic phrase structure on the processing of a verb whose argument structure matched or did not match the prior prosody-induced syntactic structure. While controls showed an N400-like effect for prosodically mismatching verb argument structures, thus indicating a stable interplay between prosody and syntax, patients with lesions in the posterior third of the CC did not show this effect. Because these patients displayed a prosody-independent semantic N400 effect, the present data indicate that the posterior third of the CC is the crucial neuroanatomical structure for the interhemispheric interplay of suprasegmental prosodic information and syntactic information.

Transcranial direct current stimulation improves naming reaction time in fluent aphasia: a double-blind, sham-controlled study.

BACKGROUND AND PURPOSE: Previous evidence suggests that anodal transcranial direct current stimulation (A-tDCS) applied to the left hemisphere can improve aphasic participants' ability to name common objects. The current study further examined this issue in a more tightly controlled experiment in participants with fluent aphasia. METHODS: We examined the effect of A-tDCS on reaction time during overt picture naming in 8 chronic stroke participants. Anode electrode placement targeted perilesional brain regions that showed the greatest activation on a pretreatment functional MRI scan administered during overt picture naming with the reference cathode electrode placed on the contralateral forehead. A-tDCS (1 mA; 20-minute) was compared with sham tDCS (S-tDCS) in a crossover design. Participants received 10 sessions of computerized anomia treatment; 5 sessions included A-tDCS and 5 included S-tDCS. RESULTS: Coupling A-tDCS with behavioral language treatment reduced reaction time during naming of trained items immediately posttreatment (Z=1.96, P=0.025) and at subsequent testing 3 weeks later (Z=2.52, P=0.006). CONCLUSIONS: A-tDCS administered during language treatment decreased processing time during picture naming by fluent aphasic participants. Additional studies combining A-tDCS, an inexpensive method with no reported serious side effects, with behavioral language therapy are recommended.

Aphasia in border-zone infarcts has a specific initial pattern and good long-term prognosis.

BACKGROUND: While border-zone infarcts (BZI) account for about 10% of strokes, studies on related aphasia are infrequent. The aim of this work was to redefine specifically their early clinical pattern and evolution. METHODS: We prospectively studied consecutive patients referred to our stroke unit within a 2-year period. Cases of aphasia in right-handed patients associated with a MRI confirmed left-sided hemispheric BZI were included. These patients had a standardized language examination in the first 48 h, at discharge from stroke unit and between 6 and 18 months later. RESULTS: Eight patients were included. Three had anterior (MCA/ACA), two posterior (MCA/PCA), two both anterior and posterior, and one bilateral BZI. All our patients initially presented transcortical mixed aphasia, characterized by comprehension and naming difficulties associated with preserved repetition. In all patients, aphasia rapidly improved. It fully recovered within a few days in three patients. Initial improvement was marked, although incomplete in the five remaining patients: their aphasias specifically evolved according to the stroke location toward transcortical motor aphasia for the three patients with anterior BZI and transcortical sensory aphasia for the two patients with posterior BZI. All patients made a full language recovery within 18 months after stroke. CONCLUSIONS: We report a specific aphasic pattern associated with hemispheric BZI, including an excellent long-term outcome. These findings appear relevant to (i) clinically suspect BZI and (ii) plan rehabilitation and inform the patient and his family of likelihood of full language recovery.

Low-frequency rTMS with language therapy over a 3-month period for sensory-dominant aphasia: case series of two post-stroke Japanese patients.

PURPOSE: To examine the safety and feasibility of therapeutic application of low-frequency repetitive transcranial magnetic stimulation (rTMS) combined with language therapy for post-stroke patients with sensory-dominant aphasia. SUBJECTS AND METHODS: Two post-stroke Japanese patients with sensory-dominant aphasia were studied. In both patients, 10 sessions of 20-minute low-frequency rTMS with 1 Hz to the Wernicke's area were provided throughout 6-day hospitalization, followed by weekly outpatient rTMS treatment for 3 months. The language therapy was also provided through the period of in- and out-patient treatment. Language function was evaluated using the Token test and the Standard Language Test of Aphasia (SLTA) at the start and end of the in-patient treatment and the end of the outpatient treatment. RESULTS: The therapeutic protocol was well tolerated throughout the in- and out-patient treatments, without any adverse effects. The scores of the Token test and certain sub-categories of SLTA increased in both patients after the in-patient rTMS treatment. Persistent improvement of the score was noted over the 3-month post-discharge period. CONCLUSIONS: The proposed protocol of long-term application of low-frequency rTMS to the Wernicke's area and language therapy is considered a safe and feasible therapeutic approach for post-stroke patients with sensory-dominant aphasia.

Aphasia and text writing.

BACKGROUND: Good writing skills are needed in almost every aspect of life today, and there is a growing interest in research into acquired writing difficulties. Most of the findings reported so far, however, are based on words produced in isolation. The present study deals with the production of entire texts. AIMS: The aim was to characterize written narratives produced by a group of participants with aphasia. METHODS & PROCEDURES: Eight persons aged 28-63 years with aphasia took part in the study. They were compared with a reference group consisting of ten participants aged 21-30 years. All participants were asked to write a personal narrative titled 'I have never been so afraid' and to perform a picture-based story-generation task called the 'Frog Story'. The texts were written on a computer. OUTCOME & RESULTS: The group could be divided into participants with low, moderate, and high general performance, respectively. The texts written by the participants in the group with moderate and high writing performance had comparatively good narrative structure despite indications of difficulties on other linguistic levels. CONCLUSIONS & IMPLICATIONS: Aphasia appeared to influence text writing on different linguistic levels. The impact on overall structure and coherence was in line with earlier findings from the analysis of spoken and written discourse and the implication of this is that the written modality should also be included in language rehabilitation.

Acalculia in a patient with severe language disturbances: how do we test it?

The present paper describes a case of a patient with severe Wernicke aphasia, which when tested with a number processing and calculation battery adapted to his difficulties showed remarkable arithmetic skills. These findings suggest that the patients with severe cognitive impairments (e.g., aphasia, apraxia) should be tested with batteries adapted to their disturbances because using a standard test may bias the results.

Revisiting 'The influence of literacy in paraphasias of aphasic speakers'.

Literature suggests that illiterate subjects are unaware of the phonological structure of language. This fact may influence the characteristics of aphasic speech, namely the structure of paraphasias. A battery of tests was developed for this study to be used with aphasic subjects (literate and illiterate), in order to explore this topic in more detail. This article aims to present the experimental design and the results of this test battery composed of two sub-tests: (i) a naming test with words that belong to three distinct groups: high frequency simple words (HFSW), low frequency simple words (LFSW), and low frequency complex words (LFCW); and (ii) a word repetition test. The variables of literacy, frequency and word morphology, and their effect on the performance of aphasic groups, were correlated in this study. Morphology was the variable that exercised the greatest influence on the verbal production of the participants.

Recursion in aphasia.

This study investigates how aphasic impairment impinges on syntactic and/or semantic recursivity of human language. A series of tests has been conducted with the participation of five Hungarian speaking aphasic subjects and 10 control subjects. Photographs representing simple situations were presented to subjects and questions were asked about them. The responses are supposed to involve formal structural recursion, but they contain semantic-pragmatic operations instead, with 'theory of mind' type embeddings. Aphasic individuals tend to exploit the parallel between 'theory of mind' embeddings and syntactic-structural embeddings in order to avoid formal structural recursion. Formal structural recursion may be more impaired in Broca's aphasia and semantic recursivity may remain selectively unimpaired in this type of aphasia.