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In Pursuit of Communication without Broca's or Wernicke's area
Full text linkThis case study presents a treatment approach with innovative software for an individual with apraxia of speech and global aphasia from a severe anoxic injury. This paper proposes that aspects of the ability to communicate are available even when core capacities of the language system are dysfunctional (Willems, Benn, Hagoort, Toni, & Varley, 2011). Most of the literature reports that prognosis is bleak for individuals diagnosed as globally aphasic and remain so at one month post. The expected course of recovery is improved comprehension but little functional speech (Sarno, Silverman & Sands, 1970). As such, this treatment was designed to use non-lexical routes toward communication and thereby achieve a better outcome
Evolution of aphasic naming errors following phonomotor treatment
Full text linkThe primary outcome measures for aphasia treatment investigations targeting anomia typically include naming accuracy of trained and untrained words. Recently, several treatment investigations have also included error analyses that closely look at the way in which word retrieval breaks down pre-treatment vs. post-treatment (Gordon, 2007; Kendall, Pompon, Brookshire, Minkina, & Bislick, 2013; Kiran & Johnson, 2008, Kiran & Thompson, 2003). In one such analysis, Kendall et al. (2013) investigated treatment-induced changes in aphasic naming errors following a phonomotor treatment for anomia. The study was rooted in an interactive two-stage model of word retrieval, in which world retrieval is initiated with activation of semantic representations, allowing for access of the word’s lemma (which holds grammatical properties), while phonological representations are accessed in the second stage (Dell, 1986). In the analyses of confrontation naming errors in ten people with aphasia, several trends were noted immediately following treatment: a decrease in the proportion of omissions on trained words, and an increase in the proportion of mixed (phonologically and semantically related) errors on untrained words. These results suggested that treatment led to more precise activation of nodes supporting word retrieval.
The present study sought to replicate this error proportion analysis in a larger group of participants and expand the analysis to explore changes in raw numbers of errors. The following research questions were asked both for trained and untrained words:
Preliminary research question
1) Is there a significant difference between picture naming accuracy pre-treatment vs. immediately post-treatment, and pre-treatment vs. three months post-treatment?
Main research questions
2) Is there a significant difference in raw numbers of various error types made during picture naming pre-treatment vs. immediately post-treatment, and pre-treatment vs. three months post-treatment?
3) Is there a significant difference in error type proportions (the number of each error type divided by the total errors made) observed during picture naming pre-treatment vs. immediately post-treatment, and pre-treatment vs. three months post-treatment
Using neuroimaging to classify aphasia
Full text linkThe proper classification of aphasia based on clinical symptoms has been debated for well over a century. Much of the early debates centered on relating localized brain damage to a constellation of speech and language impairments. The premise behind much of this work was based on the notion that lesion-symptom mapping could reveal how language was organized in the brain (Broca, 1861, 1865; Dejarine, 1906; Marie, 1906). Although the principle for classifying aphasia based on specific symptoms has been fervently challenged (e.g. Head, 1926) it is still customary to report aphasia types in clinical studies of aphasia. Similar symptoms in sub-groups of patients suggests a similar pattern of brain damage. Nevertheless, it remains unclear if specific aphasia types can be diagnosed simply based on the location of cortical damage. One way to examine this issue would be to relate lesion patterns to aphasia types using multivariate pattern analysis (MVPA). MVPA of neuroimaging data has been successfully used to diagnose diseases such as dementia, schizophrenia, and Parkinson's disease (Orru et al., 2012). In the present study, we demonstrate how MVPA can be used to predict aphasia type in persons with chronic stroke. Unlike previous studies that perform the analysis on voxels (using MRI scans), we trained a classifier on the proportional damage to brain areas (defined with a brain atlas). In addition, we computed the loadings that reflect the contribution of each brain area to classification
Treatment intensity and the effect of repetition priming on naming performance in individuals with anomia
No full textClinical aphasia researchers have demonstrated efficacy across both phonological and semantic treatment approaches for individuals with anomia (e.g., Boyle, 2004; Kendall, et al., 2008; Renvall et al., 2007). As this research continues to emerge, clinicians are gaining invaluable knowledge about the ideal treatment approach to select for each client or treatment context. Simultaneously, neuroscience research is progressing rapidly and clinical researchers have begun to manipulate principles of neuroplasticity to optimize treatment paradigms (e.g., Kleim & Jones, 2008; Kurland, et al., 2010; Ludlow et al., 2008). One variable that has gained a substantial amount of attention is treatment intensity; participants who receive a greater number of treatment sessions improve to a greater degree than those who receive conventional aphasia therapy (e.g., Brady, et al., 2012; Meinzer et al., 2011). Research protocols have yet to be designed that systematically manipulate intensity variables to estimate the amount of treatment required to best facilitate improved language skills in persons with aphasia (PWA). That is, a majority of the treatment intensity evidence comes from studies that were designed to assess the efficacy of specific treatment approaches. The purpose of this study was to directly investigate the influence of intensity and repetition on naming performance, while simultaneously removing the issue of treatment approach. A repetition priming paradigm was used to assess the influence of treatment intensity and stimulus dosage on the acquisition and maintenance of picture naming accuracy for PWA
Assessing the long-term impact of aphasia center participation
No full textComprehensive aphasia centers are a growing trend in North America and have begun to influence service delivery for individuals with aphasia and their families. Such centers are grounded in group interaction and are intensive in terms of participation time. Consistent with principles of Life Participation Approaches (LPAA, 2001), centers incorporate programming across a range of experiences and activities, including conversation groups, technology and interactive programming (e.g., Skyping across centers), as well as outreach initiatives. Early examples include The Aphasia Institute in Toronto, the Aphasia Center of California, and Connect in London (Elman, 2007a). Simmons-Mackie and Holland (2011) conducted a survey that identified 33 such centers, with the majority opening in the preceding 10 years. Since that date, these authors estimate that at least 8 new centers have been developed and staffed.
There are many obstacles to collecting effectiveness data in aphasia centers such as those described above. Heterogeneity of programming is an obvious one, compounded, in most cases, by limited professional staff and reliance on trained, but not necessarily equally talented volunteers for a substantial number of activities. Weather, transportation issues, self-selection of activities that are of interest to individual members, moving, illnesses and vacation schedules, as well as the very positive decision that members’ lives have moved beyond the type of support provided by Center programming, also contributes to heterogeneity. Finally, time and resources for collection of pre- and post-involvement data are typically limited, and research participation in most aphasia centers is voluntary. Nevertheless, we believe that, in much the same ways that data can be gathered across public schools to demonstrate their effectiveness, consistent data can be gathered to support the value of aphasia centers.
It seems reasonable to assume that the relatively well-documented benefits of participating in an aphasia group would apply to aphasia centers (Avent, 1997; Elman, 2007a, b; Elman & Bernstein-Ellis, 1999). However, direct research on the impact of aphasia centers is limited (Hoen, Thelander, & Worsley, 1997; Van der Gaag et al., 2005). This presentation will describe the long-term impact of participation in programming at two well-established1 community-based aphasia Centers, referred to here as Centers A and B. Both provide two full days of programming for 6-8 hours weekly, with additional time spent in socializing and operate on three fifteen week terms each calendar year. They share similar philosophies, and are of somewhat similar size in terms of participants and staff directly involved in their programs. A similar core assessment battery is used at both centers. This paper will present results of initial and one and two year follow-up data concerning the effects of involvement at both sites
Transcranial Direct Current Stimulation and Aphasia Treatment: A Pilot Study of Anodal, Cathodal and Sham Stimulation
No full textTranscranial direct current stimulation (tDCS) may potentially enhance language therapy outcomes in aphasia. We report behavioral results for twelve participants with chronic aphasia matched for severity and randomized to receive anodal, cathodal or sham stimulation to the left hemisphere, concurrent with intensive speech-language therapy. Importantly, tDCS (1mA for 13 minutes) given 5 days a week over a prolonged period of time (6 weeks) was found to be safe. There was an advantage of both anodal and cathodal stimulation over sham stimulation. Cathodal stimulation to the left hemisphere may be a viable option and should not be overlooked in future research
What can speech production errors tell us about cross-linguistic processing in bilingual aphasia? Evidence from 4 English/Afrikaans speaking individuals with aphasia.
No full textIn an effort to inform clinical practice and our understanding of bilingual aphasia, we examined differential performance in lexical retrieval abilities between first (L1) and second acquired language (L2), types of errors produced, and if performance was influenced by degree of cognate overlap in 4 bilingual aphasic individuals. Methods: A case series analysis of four Afrikaans/English bilingual aphasic individuals whose confrontation naming data were subjected to broad phonetic transcription was employed. Research questions were directed toward between language differences in lexical retrieval abilities, the influence of performance by degree of cognate overlap and types of errors produced. Results: Three participants showed significantly higher whole word confrontation naming accuracy in L1 relative to L2. One participant showed no difference. Performance for everyone was the poorest for low cognate overlap words. The largest proportion of error type for 3 participants in both L1 and L2 was omission. Discussion: These findings show that while all participants had aphasia, their relative naming impairments were consistent with their relative proficiency and use patterns prior to their stroke. The participant without between language differences was equally proficient in both languages and the remaining 3 participants showed an advantage consistent with the language used most frequently
Inter- and Intra-Individual Variability in Non-Linguistic Attention in Aphasia
Full text linkThe cognitive skill of attention has previously been found to be impaired in persons with aphasia (PWA) relative to control participants (e.g., Murray, 2012). However, no study to date has examined the degree to which attention fluctuates from day to day in PWA, despite the fact that other neurologically impaired populations, such as Alzheimer’s and Parkinson’s patients, have been found to exhibit a greater degree of day-to-day variability in attention than controls (Burton, Strauss, Hultsch, Moll, & Hunter, 2006). We suggest that day-to-day intra-individual variability (DTD-IIV) in attention is an important area of investigation in aphasia, and furthermore that inter-individual differences in DTD-IIV in attention may be critical in reliably predicting treatment outcomes. The expectation that an individual will improve her skills over time as a function of treatment is based on the assumption that she is able to pay attention consistently during each session. If an individual is in fact able to attend consistently each day, this assumption is fair; however, if her attention fluctuates from day to day, it seems unlikely that she will show rapid or steady improvement. With this in mind, the goal of this study was to systematically assess five types of non-linguistic attention in both PWA and control participants, using a novel computerized task and repeated sampling design. Analyses examined reaction times as well as DTD-IIV
A Moderately Intensive Functional Treatment For Severe Auditory Comprehension Deficits Associated with Aphasia
No full textSevere, chronic, auditory comprehension deficits secondary to aphasia can adversely impact an individual’s quality of life by limiting successful communication interactions (Bose et al., 2009). Furthermore, individuals lacking awareness of comprehension deficits may be less inclined to compensate for communication breakdowns (Knollman-Porter, Dietz, & Groh, 2012).
Interventions utilizing intense and repetitive stimulation are recommended to promote neuroplasticity, and therefore, language function following a stroke (Kleim & Jones, 2008; Kurland et al., 2012). More specifically, highly intensive treatment protocols (two hours a day, five days a week for three weeks) for severe comprehension deficits have demonstrated promising gains in word comprehension and awareness with corrective feedback and researcher-selected stimuli (Knollman-Porter et al., 2012).
However, not all clients and caregivers can tolerate intensive treatment protocols. Additionally, the importance of stimuli type, particularly personally relevant stimuli, has been suggested in promoting treatment outcomes (Hinckley & Carr, 2005; McKelvey et al., 2010). Therefore, further research is needed to examine more functional treatment options for individuals with comprehension deficits. This study investigated the impact of a moderately intensive treatment protocol using personally relevant stimuli and corrective feedback on auditory comprehension and self-awareness in individuals with severe, chronic, aphasia
Working Memory Treatment for an Individual with Chronic Aphasia: A Case Study
No full textWorking memory (WM) is defined as a storage system limited in its capacity and involved in maintaining and manipulating information over short periods of time (Baddeley, 2003). In WM tasks, individuals are required to simultaneously store certain items in memory while updating the contents of their WM. It has been proposed that WM interacts with language abilities and deficits in WM influence language performance (Baddeley, 2003; Carpenter, & Just, 1989; Murray, 2012). Importantly, individuals with aphasia often show WM and short-term memory (STM) deficits, which may negatively affect language symptoms and recovery, and accordingly WM treatment may represent an efficient approach to addressing these individuals’ cognitive and linguistic impairments (Kalinyak-Fliszar, Kohen, & Martin, 2011; Murray, 2012; Martin et al., 2012).
WM treatment for individuals with aphasia, however, has not yet been intensively studied (Murray, 2012). Previous results indicate that WM in individuals with aphasia can be improved with training (e.g., Kalinyak-Fliszar et al., 2011; Mayer & Murray, 2002; Vallat et al., 2005). Nonetheless, variable amounts of generalization to language abilities and types of untrained cognitive and linguistic functions responding to the WM treatment have been reported. Accordingly, to examine further the potential of WM training to remediate the cognitive-linguistic symptoms of individuals with aphasia, we administered a treatment with tasks designed not only to target WM skills but also semantic processing, the linguistic ability most compromised in our aphasic participant. The research questions were:
a) Would our participant with chronic aphasia demonstrate improved WM through treatment?
b) Would our participant demonstrate improved language performance given WM tasks that involved verbal stimuli