Regina Jokel

Treating anomia in semantic dementia: improvement, maintenance, or both?

A treatment programme for AK, an anomic patient with semantic dementia is described. The programme was based on home practice and resulted in re-learning the names of some objects AK could not name and/or comprehend prior to the treatment. The effects of treatment were still present one month post-treatment for items that AK could not name but could comprehend prior to treatment. In addition to items that AK could not name, items that she could both understand and name were also included in the programme. This allowed us to evaluate the influence of practice on the retention of words that appeared to be intact at the outset of the investigation. Results indicated that practice delayed the progression of loss. In addition, the programme was designed jointly with AK who made many important decisions related to treatment.

Errorless learning of computer-generated words in a patient with semantic dementia

This study explores the effectiveness and feasibility of an errorless learning approach administered via a computer-based treatment for anomia to CS, an individual with semantic dementia. Using a multiple baseline across behaviours design, we explored treatment specific effects, maintenance and generalisation of gains derived from the MossTalk Words® therapy programme. CS was treated on three lists of words, each containing items for which CS retained some semantic knowledge and some for which he did not. CS was tested immediately after therapy, and one and three months later. Improved naming was maintained on all lists at all testing intervals. In addition, among those words for which CS retained some semantic knowledge, he maintained the ability to name all practised words, but only half of the not practised words. This study underscored the feasibility of computer-based treatments for anomia in progressive disorders, demonstrated the effectiveness of an errorless approach in semantic dementia in re-training lost words, and provided justification for training words that patients still have in their daily vocabulary. The results are discussed in relation to other treatment studies in progressive aphasia and in the context of factors necessary for therapeutic success in semantic dementia.

Quest for the best: Effects of errorless and active encoding on word re-learning in semantic dementia

Semantic dementia is a neurocognitive disorder characterised by a steady and progressive loss of semantic knowledge in the presence of relatively preserved other cognitive skills. Recent treatment studies have proven that language rehabilitation aimed at anomia in semantic dementia can be successful. The objective of this study was to examine the separate and interactive effects of errorless vs. errorful and active vs. passive learning approaches to anomia and their effects on naming and comprehension of treated items, as well as maintenance and generalisation of treatment gains. Seven participants with semantic dementia re-learned two sets of words (one for which participants retained auditory comprehension, and one for which they did not) in each of four different treatment methods based on those approaches. Errorless learning proved more successful than errorful learning in restoring lexical representations in all but one participant while there was no interaction between effects of errorless and active approaches on treatment success. Maintenance of treatment gains showed an advantage for errorless learning at one but not three months post-treatment, although all overall gains were maintained to a significant degree at both time points. Effects of both treatment and maintenance were stronger for items for which participants showed preserved auditory comprehension. The results are discussed in a framework of progressive language disorders and applicability of errorless methods to language rehabilitation in semantic dementia.

Word retrieval therapies in primary progressive aphasia

Background: Primary progressive aphasia (PPA) with its three variants is a progressive neurodegenerative dementia in which language impairment is the first and most dominant symptom. Traditionally, speech-language pathologists who deliver therapy to adults with acquired neurogenic language disorders shy away from treatment of progressive aphasia as there is no promise of lasting effects and only limited data regarding treatment efficacy. Aims: This paper comprises the most current review of the literature focused on treatment of naming impairments in PPA, and aims to encourage and assist clinicians in selecting intervention approaches for individuals with PPA. It highlights current trends and challenges in delivering successful therapy for naming deficits in PPA. Main Contribution: We reviewed papers that reported different forms of naming therapy for patients with PPA, which included interventions that, although not always aimed directly at anomic deficits, brought about improvement in naming. Immediate gains, maintenance, and generalisation effects are summarised, along with a variety of approaches and methodologies that can be applied to the PPA population. We also provide a list of factors that were found to contribute to the success of therapy and to the maintenance and/or generalisation of treatment gains. Conclusions: Current literature delivers encouraging evidence for clinicians wanting to provide naming therapy to patients with PPA. Although PPA is a progressive disorder, both the immediate treatment effects and, in many cases, maintenance results show that improvements are possible. The issues of generalisation of naming gains beyond the clinician’s office still require more studies to determine the best conditions, designs, and patient suitability.

Relearning lost vocabulary in nonfluent progressive aphasia with MossTalk Words

Background: The literature on aphasia has been growing rapidly, with reports of different therapeutic approaches for a post‐stroke anomia. While individuals with post‐stroke anomia frequently recover to some extent, the other end of the aphasia recovery continuum is occupied by those who experience relentless language dissolution as a result of progressive disorders such as primary progressive aphasia. One of the most recent additions to the field of aphasia rehabilitation is therapy whereby either part of or the entire therapy is administered via computer‐based programmes. There have been few treatment studies investigating the rehabilitation of language abilities in people with primary progressive aphasia (PPA). Aims: The objectives of this investigation were to examine the ability of PPA individuals to relearn lost words and to determine the extent of benefits derived from MossTalk Words®, a computer‐based treatment for anomia. Methods and Procedures: Using a multiple baseline across behaviours design, we explored treatment‐specific effects, maintenance, and generalisation of improvements derived from this therapy programme. Two participants with nonfluent PPA were treated, each on three lists of words for which low and stable baselines were first established. Sessions occurred two to three times a week. Treatment involved the presentation of a picture on the computer screen, with the participants being required to name it. Success in treatment was measured by probing list naming every second session. Once a participant attained 80% accuracy over two consecutive probes, or participated in 12 sessions (whichever occurred first), treatment of a list was terminated and the next list was started. Each participant was tested on all items immediately after therapy, and again 1 month later. Outcomes and Results: Both participants improved their naming skills with the MossTalk Words®. P1 required only four sessions to reach the proposed criterion of 80% (up to 100%) correct on each list. The effects of treatment were maintained immediately and, to a lesser degree, 4 weeks later. P2 required all 12 sessions for each of the three lists. Results were variable immediately after testing, but seemingly maintained 4 weeks later. Conclusions: The results demonstrate that both participants with primary progressive aphasia benefited (although to a different extent) from a computer‐based treatment for anomia. These results are encouraging and suggest that such a treatment may be a viable therapy approach for patients who suffer from PPA in the absence of a generalised cognitive impairment. We are indebted to both participants for their cooperation and tenacity, and to our talented research assistants Eleanor Arabia and Lyndsay White. We also thank Ruth Fink for making the MossTalk Words® available to us. This study was supported by a CIHR IA Fellowship to R. Jokel, and a CIHR Doctoral Award to J. Cupit. The authors acknowledge the support of the Toronto Rehabilitation Institute, which receives funding under the Provincial Rehabilitation Research Program from the Ministry of Health and Long Term Care in Ontario, Canada.

Sentence comprehension in semantic dementia: a longitudinal case study.

Abstract Sentence comprehension abilities were investigated in a patient with semantic dementia who was administered tests of semantic knowledge and sentence comprehension over a 5-year period. Results showed that despite a severe and continual degradation in semantic knowledge, syntactic comprehension abilities remained largely intact. Evidence was also found for a codependency between semantics and syntax in a task in which knowledge about conceptual number influenced subject-verb agreement in the patient and in control participants. Results are discussed in relation to the nature of the sentence comprehension impairment in semantic dementia and with reference to the modularity of the components of the language processing system.

Functional reorganization of language networks for semantics and syntax in chronic stroke: Evidence from MEG.

Using magnetoencephalography, we investigated the potential of perilesional and contralesional activity to support language recovery in patients with poststroke aphasia. In healthy young controls, left‐lateralized ventral frontotemporal regions responded to semantic anomalies during sentence comprehension and bilateral dorsal frontoparietal regions responded to syntactic anomalies. Older adults showed more extensive bilateral responses to the syntactic anomalies and less lateralized responses to the semantic anomalies, with decreased activation in the left occipital and parietal regions for both semantic and syntactic anomalies. In aphasic participants, we observed compensatory recruitment in the right hemisphere (RH), which varied depending on the type of linguistic information that was processed. For semantic anomalies, aphasic patients activated some preserved left hemisphere regions adjacent to the lesion, as well as homologous parietal and temporal RH areas. Patients also recruited right inferior and dorsolateral frontal cortex that was not activated in the healthy participants. Responses for syntactic anomalies did not reach significance in patients. Correlation analyses indicated that recruitment of homologous temporoparietal RH areas is associated with better semantic performance, whereas higher accuracy on the syntactic task was related to bilateral superior temporoparietal and right frontal activity. The results suggest that better recovery of semantic processing is associated with a shift to ventral brain regions in the RH. In contrast, preservation of syntactic processing is mediated by dorsal areas, bilaterally, although recovery of syntactic processing tends to be poorer than semantic. Hum Brain Mapp 37:2869–2893, 2016.

Identifying Dysfunctional Cortex: Dissociable Effects of Stroke and Aging on Resting State Dynamics in MEG and fMRI

Spontaneous signals in neuroimaging data may provide information on cortical health in disease and aging, but the relative sensitivity of different approaches is unknown. In the present study, we compared different but complementary indicators of neural dynamics in resting-state MEG and BOLD fMRI, and their relationship with blood flow. Participants included patients with post-stroke aphasia, age-matched controls, and young adults. The complexity of brain activity at rest was quantified in MEG using spectral analysis and multiscale entropy (MSE) measures, whereas BOLD variability was quantified as the standard deviation (SDBOLD), mean squared successive difference (MSSD), and sample entropy of the BOLD time series. We sought to assess the utility of signal variability and complexity measures as markers of age-related changes in healthy adults and perilesional dysfunction in chronic stroke. The results indicate that reduced BOLD variability is a robust finding in aging, whereas MEG measures are more sensitive to the cortical abnormalities associated with stroke. Furthermore, reduced complexity of MEG signals in perilesional tissue were correlated with hypoperfusion as assessed with arterial spin labeling (ASL), while no such relationship was apparent with BOLD variability. These findings suggest that MEG signal complexity offers a sensitive index of neural dysfunction in perilesional tissue in chronic stroke, and that these effects are clearly distinguishable from those associated with healthy aging.

Case Study: Mirror reading, writing and backward speech in a woman with a head injury: a case of conversion disorder

This paper presents a case of a 46-year-old, right-handed female, L.R., admitted to a behavioural neurology unit after sustaining a mild head injury. The patient presented as a very complex case with difficulties in neuropsychological, emotional and medical domains. The unusual features of her backward speech, and mirror reading and writing, evident upon admission, are described here. Results of assessment are considered in relation to conversion disorder and existing theories on mirror phenomena.

Behavioural and neuroimaging changes after naming therapy for semantic variant primary progressive aphasia

The objectives of this study were to examine the effects of a successful naming intervention on naming performance and brain activity in individuals with the semantic variant of primary progressive aphasia (svPPA). Four participants with svPPA were scanned while performing phonologically- and semantically-based tasks before and after an intense, 20-h naming therapy that followed the principles of errorless learning whereby errors were eliminated from the learning process. Five healthy control participants were scanned at the outset of the study and did not receive treatment. The results showed that in svPPA participants, successful re-learning of forgotten vocabulary was accompanied by activation of a larger network in bilateral brain regions and that the level of activation in the left anterior lobe may be inversely correlated with severity of semantic impairment. Our findings have implications for treatment in svPPA patients and suggest that semantic cues can improve naming, in spite of significant semantic impairment. The results indicate that intensive language therapy can lead to behavioural gains and neuroplastic changes even in individuals with more advanced anterior temporal lobe atrophy.