Primary Progressive Aphasias and Apraxia of Speech

Behavioral Treatment for Speech and Language in Primary Progressive Aphasia and Primary Progressive Apraxia of Speech: A Systematic Review

Primary progressive aphasia (PPA) and primary progressive apraxia of speech (PPAOS) are neurodegenerative syndromes characterized by progressive decline in language or speech. There is a growing number of studies investigating speech-language interventions for PPA/PPAOS. An updated systematic evaluation of the treatment evidence is warranted to inform best clinical practice and guide future treatment research. We systematically reviewed the evidence for behavioral treatment for speech and language in this population. Reviewed articles were published in peer-reviewed journals through 31 May 2021. We evaluated level of evidence, reporting quality, and risk of bias using a modified version of the American Speech-Language Hearing Association (ASHA) Levels of Evidence, an appraisal point system, additional reporting quality and internal/external validity items, and, as appropriate, the Single Case Experimental Design Scale or the Physiotherapy Evidence Database - PsycBITE Rating Scale for Randomized and Non-Randomized Controlled Trials. Results were synthesized using quantitative summaries and narrative review. A total of 103 studies reported treatment outcomes for 626 individuals with PPA; no studies used the diagnostic label PPAOS. Most studies evaluated interventions for word retrieval. The highest-quality evidence was provided by 45 experimental and quasi-experimental studies (16 controlled group studies, 29 single-subject designs). All (k = 45/45) reported improvement on a primary outcome measure; most reported generalization (k = 34/43), maintenance (k = 34/39), or social validity (k = 17/19) of treatment for at least one participant. The available evidence supports speech-language intervention for persons with PPA; however, treatment for PPAOS awaits systematic investigation. Implications and limitations of the evidence and the review are discussed.

Incidence of Primary Progressive Apraxia of Speech and Primary Progressive Aphasia in Olmsted County, MN, 2011-2022

BACKGROUND AND OBJECTIVE

No epidemiologic studies have formally assessed the incidence of primary progressive aphasia (PPA) and primary progressive apraxia of speech (PPAOS). Thus, we decided to assess the incidence of these disorders in Olmsted County, MN, between 2011 and 2022, and to characterize clinical, radiographic, and pathologic characteristics of these patients.

METHODS

This was a retrospective examination of data from a population-based cohort of patients with PPA and PPAOS prospectively identified in Olmsted County, MN, from 2011 to 2022. The incidence of PPA among adults (older than 18 years) was calculated for Olmsted County as the number of patients per 100,000 person-years during the study period. The adult population of Olmsted County was determined by the annual catchment population reported by the Rochester Epidemiological Project for each year 2011-2022. A behavioral neurologist verified the clinical diagnoses and determined subtypes.

RESULTS

We identified 10 patients (60% female) within the study period (median age of symptoms onset: 70 years; range: 66-73), 8 with PPA and 2 with PPAOS. Of the 8 patients with PPA (6 female patients, 2 male patients), 2 met criteria for non-fluent variant PPA (nfvPPA), 3 for logopenic variant PPA (lvPPA), and 3 for semantic variant (svPPA). Speech evaluation confirmed the clinical diagnoses in all patients and all showed typical imaging findings consistent with their respective subtype. Six patients (2 PPAOS, 2 nfvPPA, 2 lvPPA) died and 3 underwent autopsy (2 PPAOS, 1 nfvPPA), confirming the pathologic diagnosis of progressive supranuclear palsy. The incidence of PPA + PPAOS was 0.70 persons per 100,000 person-years (95% CI 0.34-1.29 persons per 100,000) during the study period. The incidence of PPAOS was 0.14 persons per 100,000 person-years (95% CI 0.02-0.55 persons per 100,000), whereas for the 8 patients with PPA, the incidence was 0.56 persons per 100,000 person-years (95% CI 0.24-1.10 cases per 100,000). The incidence of nfvPPA was 0.14 persons per 100,000 person-years (95% CI 0.02-0.55), 0.21 persons per 100,000 person-years (95% CI 0.04-0.61) for lvPPA, and 0.21 persons per 100,000 person-years (95% CI 0.04-0.61) for svPPA.

DISCUSSION

As a group, PPA and PPAOS are a relatively rare group of diseases. PPAOS has a slightly lower incidence than PPA as a group but similar incidence to the individual PPA variants.

Efficacy of LSVT LOUD® on Phonatory Control and Voice Quality in Patients with Primary Progressive Apraxia of Speech: Case Studies

Primary progressive apraxia of speech (PPAOS) is a neurodegenerative syndrome characterized by the progressive and initially isolated or predominant onset of difficulties in the planning/programming of movements necessary for speech production and can be accompanied by dysarthria. To date, no study has used an evidence-based treatment to address phonation control in patients with PPAOS. The aim of this study was to evaluate the feasibility and efficacy of LSVT LOUD® as a treatment for phonatory control in speakers with PPAOS. Three speakers with PPAOS received LSVT LOUD® therapy, and changes in phonatory control, voice quality and prosody were measured immediately, and one, four and eight weeks after the end of the treatment. Overall, the results suggest that the treatment is feasible and could improve voice quality, intensity, and control in some patients with PPAOS. The generalization of the results is also discussed.

Frontotemporal Dementia, Where Do We Stand? A Narrative Review

Frontotemporal dementia (FTD) is a neurodegenerative disease of growing interest, since it accounts for up to 10% of middle-age-onset dementias and entails a social, economic, and emotional burden for the patients and caregivers. It is characterised by a (at least initially) selective degeneration of the frontal and/or temporal lobe, generally leading to behavioural alterations, speech disorders, and psychiatric symptoms. Despite the recent advances, given its extreme heterogeneity, an overview that can bring together all the data currently available is still lacking. Here, we aim to provide a state of the art on the pathogenesis of this disease, starting with established findings and integrating them with more recent ones. In particular, advances in the genetics field will be examined, assessing them in relation to both the clinical manifestations and histopathological findings, as well as considering the link with other diseases, such as amyotrophic lateral sclerosis (ALS). Furthermore, the current diagnostic criteria will be explored, including neuroimaging methods, nuclear medicine investigations, and biomarkers on biological fluids. Of note, the promising information provided by neurophysiological investigations, i.e., electroencephalography and non-invasive brain stimulation techniques, concerning the alterations in brain networks and neurotransmitter systems will be reviewed. Finally, current and experimental therapies will be considered.

An Update on Apraxia of Speech

PURPOSE OF REVIEW

Apraxia of speech (AOS) is a motor speech disorder that has long been recognized to occur secondary to acute neurologic insults and, more recently, to neurodegenerative diseases as a harbinger for progressive supranuclear palsy and corticobasal syndrome. This article reviews recent findings regarding the clinic phenotypes of AOS, neuroimaging correlates, and the underlying disease processes.

RECENT FINDINGS

Two clinical subtypes of AOS map onto two underlying 4-repeat tauopathies. New imaging techniques have recently been applied to the study of progressive AOS. There is no data on the impact of behavioral intervention, although studies of nonfluent/agrammatic primary progressive aphasia that include patients with AOS suggest some benefit in speech intelligibility and maintenance. While recent findings suggest subtypes of AOS exist that are linked to molecular pathology and have important implications for disease progression, further research is needed to assess outcome of behavioral and other types of intervention.

Longitudinal changes in dopamine transporter uptake scans in progressive apraxia of speech

Purpose

To describe qualitative and quantitative longitudinal changes in dopamine transporter uptake (DaT) scan findings in progressive apraxia of speech (PAOS) patients.

Methods

DaTQUANT software was used to quantify uptake in the left and right caudate and putamen in DaT scans of 39 patients with PAOS, 19 with repeat scans. Clinical radiologic impressions were used as the gold standard for evaluating whether quantitative measures (z-score of left and right putamen and caudate uptake) aligned with gestalt impressions of DaT abnormalities and clinical impairments, cross-sectionally. Measures at first and last available DaT were used to evaluate change over time and the influence of qualitative abnormality at first visit on change over time.

Results

Cross-sectionally, 16/39 patients had abnormal DaT scans on visual read, with differences in all quantitative DaT measures between those with (ab)normal scans, but without differences in any clinical measures (apraxia of speech, aphasia, or parkinsonism). Three patients that had normal DaT scans at baseline were read as abnormal at subsequent visits, with coinciding change in quantitative measures. At the group level, across the 19 patients with repeat imaging, no statistical change in left or right caudate or putamen scores was observed despite progression of clinical indices. Abnormality at first visit did not statistically influence the rate of change over time, although trends were observed.

Conclusions

Approximately 40-50% of patients with PAOS have or will develop DaT scans that may be visually read as abnormal. Quantitative measures of DaT match visual reads cross-sectionally, but may not map to clinical progression, including of parkinsonism, observed in these patients.

Speech rate increase in primary progressive apraxia of speech and its cost on articulatory accuracy

Impaired articulation (e.g., articulatory accuracy) and prosody (e.g., slow speech rate) are considered primary diagnostic criterions for apraxia of speech both in neurodegenerative and post-stroke contexts. The primary aim of this study was to investigate the ability of participants with primary progressive apraxia of speech (PPAOS), a neurodegenerative disease characterised by initially isolated progressive apraxia of speech, to increase speech rate and the interaction between articulatory accuracy and speech rate. The secondary aim was to investigate the effect of syllable frequency and structure on this interaction. Four speakers with PPAOS, and four sex- and age-matched healthy speakers (HS) read eight two-syllable words embedded two times in a ten-syllable carrier phrase. Syllable frequency and structure were manipulated for the first syllable of the target words and controlled for the second syllable. All sentences were produced at three different target speech rates (conditions): habitual, regular (five syllables/second), and fast (seven syllables/second). Prosodic measures for target words and sentences were computed based on acoustic analysis of speech rate. Articulatory measures for words and sentences were rated based on a perceptual assessment of articulatory accuracy. Results show slower speech rate and reduced articulatory accuracy in speakers with PPAOS compared to HS. Results suggest that speakers with PPAOS also have limited ability to increase their speech rate. Finally, results suggest that articulatory complexity influences speech rate but that the cost of speech rate increase on articulatory accuracy varies greatly across speakers with PPAOS and is not necessarily related to the extent of the increase when measured in a highly structured sentence production task. Theoretical and clinical implications of these findings are discussed.

Research trends of the neuroimaging in aphasia: A bibliometric analysis and visualization analysis from 2004 to 2021

Objectives

To review the current research status of the neuroimaging of aphasia, and reveal the hotspots and frontiers of research in this field.

Methods

We searched articles related to the neuroimaging research on aphasia since Web of Science (WOS) database construction and extracted the data. CiteSpace and VOSviewer were used for the country/institution analysis, journal analysis, discipline analysis, burst keyword analysis and cited-reference cluster analysis.

Results

Of the studies retrieved from WOS, 2922 studies that related to the neuroimaging of aphasia were screened and finally included 2799 articles for research. The United States of America and University of California San Francisco were the main countries and institutions in this field. Brain had the highest impact factor in both published and cited journals. Through the discipline and topic analysis of this field, the most common category was Neurosciences and Neurology. The keyword with the strongest citation strength was “functional connectivity,” and the recent burst keywords were “functional connectivity” and “network.” The co-citation network showed seven clusters greater than 100. Among the top 5 clusters, the most recently formed cluster, Cluster #2 (progressive supranuclear palsy), had an average year of 2017. The literature in the top 5 clusters mainly focused on 3 aspects, specifically, the discovery of language processing models, injury and recovery mechanisms of post-stroke aphasia (PSA), and diagnosis of primary progressive aphasia (PPA) variants.

Conclusion

The results of this bibliometric study revealed the following three research hotspots in the neuroimaging of aphasia: clarifying the connotation of the most recognized language processing model, the dual-stream model, exploring the injury mechanism based on the dual-stream model and the recovery mechanism involving the left and right hemispheres of PSA, and determining the diagnostic criteria for PPA variants. A major research trend is to combine new neuroimaging technology, such as PET tracer technology, to realize the visual presentation of disease-specific proteins to improve the pathological diagnostic criteria of PPA variants. Accordingly, a visualized analysis of literature that uses CiteSpace provides a more rapid, repeatable and flexible method, which is more conducive to capturing research hotspots and emerging trends.

Sentence Comprehension in Primary Progressive Aphasia: A Study of the Application of the Brazilian Version of the Test for the Reception of Grammar (TROG2-Br)

Sentence-comprehension deficits have been described in patients with primary progressive aphasia (PPA). However, most instruments to address this domain in more detail and in a clinical context have not been adapted and translated into several languages, posing limitations to clinical practice and cross-language research.

Objectives

The study aimed to (1) test the applicability of the Brazilian version of the Test for Reception of Grammar (TROG2-Br) to detect morphosyntactic deficits in patients with PPA; (2) investigate the association between performance in the test and sociodemographic and clinical variables (age, years of formal education, and disease duration); (3) characterize the performance of individuals presenting with the three more common variants of PPA (non-fluent, semantic, and logopenic) and mixed PPA (PPA-Mx) and analyze whether TROG-2 may assist in the distinction of these clinical profiles.

Methods

A total of 74 cognitively healthy participants and 34 individuals diagnosed with PPA were assessed with TROG2-Br. Overall scores (correct items, passed blocks), types, and categories of errors were analyzed.

Results

In controls, block scores were significantly correlated with years of formal education (Spearman's r = 0.33, p = 004) but not with age. In PPA, age, education, and disease duration were not significantly associated with performance in the test. Controls presented a significantly higher performance on TROG2-Br compared to PPA individuals and their errors pattern pointed to mild general cognitive processing difficulties (attention, working memory). PPA error types pointed to processing and morphosyntactic deficits in nonfluent or agrammatic PPA, (PPA-NF/A), logopenic PPA (PPA-L), and PPA-Mx. The semantic PPA (PPA-S) subgroup was qualitatively more similar to controls (processing difficulties and lower percentage of morphosyntactic errors). TROG2-Br presented good internal consistency and concurrent validity.

Discussion

Our results corroborate findings with TROG-2 in other populations. The performance of typical older adults with heterogeneous levels of education is discussed along with recommendations for clinical use of the test and future directions of research.

Differential Diagnosis of Rare Subtypes of Progressive Supranuclear Palsy and PSP-Like Syndromes—Infrequent Manifestations of the Most Common Form of Atypical Parkinsonism

Presently, there is increasing interest in rare PSP (progressive supranuclear palsy) variants, including PSP-PGF (PSP-progressive gait freezing), PSP-PI (PSP-postural instability), PSP-OM (PSP-ocular motor dysfunction), PSP-C (PSP-predominant cerebellar ataxia), PSP-CBS (PSP-corticobasal syndrome), PSP-SL (PSP-speech/language disorders), and PSP-PLS (PSP-primary lateral sclerosis). Diagnosis of these subtypes is usually based on clinical symptoms, thus thorough examination with anamnesis remains a major challenge for clinicians. The individual phenotypes often show great similarity to various neurodegenerative diseases and other genetic, autoimmune, or infectious disorders, manifesting as PSP-mimicking syndromes. At the current stage of knowledge, it is not possible to isolate a specific marker to make a definite ante-mortem diagnosis. The purpose of this review is to discuss recent developments in rare PSP phenotypes and PSP-like syndromes.

Longitudinal Changes in Cognition, Behaviours, and Functional Abilities in the Three Main Variants of Primary Progressive Aphasia: A Literature Review

Primary progressive aphasias (PPAs) are a group of neurodegenerative diseases presenting with insidious and relentless language impairment. Three main PPA variants have been described: the non-fluent/agrammatic variant (nfvPPA), the semantic variant (svPPA), and the logopenic variant (lvPPA). At the time of diagnosis, patients and their families' main question pertains to prognosis and evolution, but very few data exist to support clinicians' claims. The objective of this study was to review the current literature on the longitudinal changes in cognition, behaviours, and functional abilities in the three main PPA variants. A comprehensive review was undertaken via a search on PUBMED and EMBASE. Two authors independently reviewed a total of 65 full-text records for eligibility. A total of 14 group studies and one meta-analysis were included. Among these, eight studies included all three PPA variants. Eight studies were prospective, and the follow-up duration was between one and five years. Overall, svPPA patients showed more behavioural disturbances both at baseline and over the course of the disease. Patients with lvPPA showed a worse cognitive decline, especially in episodic memory, and faster progression to dementia. Finally, patients with nfvPPA showed the most significant losses in language production and functional abilities. Data regarding the prodromal and last stages of PPA are still missing and studies with a longer follow-up observation period are needed.

Contribution of the Cognitive Approach to Language Assessment to the Differential Diagnosis of Primary Progressive Aphasia

Diagnosis of primary progressive aphasia (PPA) is essentially based on the identification of progressive impairment of language abilities while other cognitive functions are preserved. The three variants of PPA are characterized by core and supportive clinical features related to the presence or absence of language impairment in different linguistic domains. In this article, we review the cognitive neuropsychological approach to the assessment of PPA and its contribution to the differential diagnosis of the three variants. The main advantage of this assessment approach is that it goes beyond the mere description and classification of clinical syndromes and identifies impaired and preserved cognitive and linguistic components and processes. The article is structured according to the main language domains: spoken production, language comprehension, and written language. Each section includes a brief description of the cognitive processes involved in the assessment tasks, followed by a discussion of typical characteristics for each PPA variant and common pitfalls in the interpretation of the results. In addition, the clinical benefit of the cognitive neuropsychological approach for the behavioral management of PPA is briefly sketched out in the conclusion.

The Electrophysiological Correlates of Phoneme Perception in Primary Progressive Aphasia: A Preliminary Case Series

Aims: This study aimed to investigate phoneme perception in patients with primary progressive aphasia (PPA) by using the event-related potential (ERP) technique. These ERP components might contribute to the diagnostic process of PPA and its clinical variants (NFV: nonfluent variant, SV: semantic variant, LV: logopenic variant) and reveal insights about phoneme perception processes in these patients.

Method: Phoneme discrimination and categorization processes were investigated by the mismatch negativity (MMN) and P300 in eight persons with early- and late-stage PPA (3 NFV, 2 LV, 2 SV, and 1 PPA-NOS; not otherwise specified) and 30 age-matched healthy adults. The mean amplitude, the onset latency, and the topographic distribution of both components in each patient were compared to the results of the control group.

Results: The MMN was absent or the onset latency of the MMN was delayed in the patients with the NFV, LV, and PPA-NOS in comparison to the control group. In contrast, no differences in mean amplitudes and onset latencies of the MMN were found between the patients with the SV and the control group. Concerning the P300, variable results were found in the patients with the NFV, SV, and PPA-NOS, but the P300 of both patients with the LV was delayed and prolonged with increased mean amplitude in comparison to the control group.

Conclusion: In this preliminary study, phoneme discrimination deficits were found in the patients with the NFV and LV, and variable deficits in phoneme categorization processes were found in all patients with PPA. In clinical practice, the MMN might be valuable to differentiate the SV from the NFV and the LV and the P300 to differentiate the LV from the NFV and the SV. Further research in larger and independent patient groups is required to investigate the applicability of these components in the diagnostic process and to determine the nature of these speech perception deficits in the clinical variants of PPA.

Progressive apraxia of speech: delays to diagnosis and rates of alternative diagnoses

BACKGROUND

Progressive apraxia of speech (PAOS) is a neurodegenerative disorder of speech programming distinct from aphasia and dysarthria, most commonly associated with a 4-repeat tauopathy. Our objective was to better understand the reasons for possible delays or diagnostic errors for patients with PAOS.

METHODS

Seventy-seven consecutive PAOS research participants from the Neurodegenerative Research Group were included in this study. The medical records for these patients were reviewed in detail. For each speech-related visit, data such as the chief complaint, clinical findings, and neuroimaging findings were recorded.

RESULTS

Apraxia of speech was the initial diagnosis in 20.1% of participants at first evaluation noted in the historical record. Other common diagnoses included primary progressive aphasia (PPA) (20.1%), dysarthria (18.18%), MCI/Dementia (6.5%), and motor neuron disease (3.9%). It took a median of 2.02 (range: 0.16-8.18) years from symptoms onset for participants to receive an initial diagnosis and 3.00 (range: 0.49-9.42) years to receive a correct diagnosis. Those who were seen by a speech-language pathologist (SLP) during their first documented encounter were more likely to be correctly diagnosed with PAOS (37/48) after SLP consultation than those who were not seen by an SLP on initial encounter (5/29) (p < 0.001).

CONCLUSION

Approximately 80% of patients with PAOS were imprecisely diagnosed at their first visit, with it taking a median of 3 years from symptom onset to receiving a diagnosis of PAOS. Being seen by a speech-language pathologist during the initial evaluation increased the likelihood of a correct apraxia of speech diagnosis.

Progressive apraxia of speech in Quebec French speakers: A case series

BACKGROUND

The term progressive apraxia of speech (PAOS) is used to describe speakers presenting with isolated or dominant apraxia of speech in the context of a neurodegenerative syndrome, including primary progressive apraxia of speech (PPAOS) and dominant progressive apraxia of speech (DAOS), respectively. Its motor speech profile has been increasingly explored in the last decade, but description remains vague and very English oriented, although the effect of speakers' language on motor speech phenotypes is increasingly recognized. Although some studies suggest that speakers presenting with isolated PAOS (PPAOS) versus dominant PAOS with concomitant aphasia (DAOS) should be differentiated, distinct characteristics of the two presentations are unclear. Furthermore, a careful description of their clinical presentation in languages other than English is required.

AIMS

To describe the motor speech characteristics of Quebec French-speaking participants with prominent PAOS and to explore the communication profile of those presenting more specifically with isolated PAOS (PPAOS), and with dominant PAOS and concomitant aphasia (DAOS).

METHODS & PROCEDURES

A thorough effort to recruit all speakers presenting with PAOS in the larger population areas of the province of Quebec was conducted over a 3-year span. A total of nine participants with PAOS (pwPAOS; PPAOS = 5, DAOS = 4) underwent a comprehensive language and motor speech assessment, and a cognitive screening. Their performance was compared with 30 matched healthy controls.

OUTCOMES & RESULTS

As a group, pwPAOS differed from healthy speakers on all acoustic and perceptual measures. The PPAOS and PAOS subgroups were similar on several measures, but participants from the PPAOS subgroup tended to perform better on articulatory measures and maximum speech rate tasks.

CONCLUSIONS & IMPLICATIONS

This study provides an in-depth analysis of motor speech characteristics of PAOS in Quebec French speakers and adds further evidence for the differentiation of PPAOS and DAOS. Combining simple perceptual and acoustic analyses represent a promising approach to distinguish the two variants and identify treatment targets. What this paper adds What is already known on this subject Progressive apraxia of speech (PAOS) is a neurodegenerative syndrome characterized by progressive and initially isolated or dominant apraxia of speech (primary progressive apraxia of speech [PPAOS] and dominant progressive apraxia of speech [DAOS], respectively). Studies mostly report articulatory and prosodic deficits in PAOS, but concomitant deficits such as dysarthria and executive dysfunction are also reported. The description of motor speech skills in PAOS remains vague and English-oriented. Studies suggest that speakers presenting with isolated PAOS vs dominant PAOS with concomitant aphasia should be differentiated, but distinct characteristics of the two presentations are unclear. What this study adds to existing knowledge To the best of the authors' knowledge, this study is the first to report transversal data of Quebec-French participants with PPAOS and DAOS. Moreover, this study is a first step towards identifying potential characteristics that could facilitate the diagnosis of PPAOS and DAOS in Quebec French. It makes a significant contribution to our understanding of progressive apraxia of speech in different cultural languages. What are the potential or actual clinical implications of this work? This study also initiates the search for sensitive tasks for the diagnosis of those speakers (which is an important process), in addition to identifying the core characteristics of PAOS, DAOS, and PPAOS in the development of an assessment battery for this population.

Neuroimaging in Frontotemporal Lobar Degeneration: Research and Clinical Utility

Frontotemporal lobar dementia (FTLD) is a clinically and pathologically complex disease. Advances in neuroimaging techniques have provided a specialized set of tools to investigate underlying pathophysiology and identify clinical biomarkers that aid in diagnosis, prognostication, monitoring, and identification of appropriate endpoints in clinical trials. In this chapter, we review data discussing the utility of neuroimaging biomarkers in sporadic FTLD, with an emphasis on current and future clinical applications. Among those modalities readily utilized in clinical settings, T1-weighted structural magnetic resonance imaging (MRI) and 18F-fluorodeoxyglucose positron emission tomography (FDG-PET) are best supported in differential diagnosis and as targets for clinical trial endpoints. However, a number of nonclinical neuroimaging modalities, including diffusion tensor imaging and resting-state functional connectivity MRI, show promise as biomarkers to predict progression and as clinical trial endpoints. Other neuroimaging modalities, including amyloid PET, Tau PET, and arterial spin labeling MRI, are also discussed, though more work is required to establish their utility in FTLD in clinical settings.

Communication Limitations in Patients With Progressive Apraxia of Speech and Aphasia

Purpose Individuals with primary progressive apraxia of speech (AOS) have AOS in which disruptions in articulation and prosody predominate the speech pattern. Many develop aphasia and/or dysarthria later in the disease course. The aim of this study was to describe the communication limitations in these patients, as measured by (a) the patient via the Communicative Participation Item Bank (CPIB) and (b) the speech-language pathologist via the American Speech-Language-Hearing Association's (ASHA) Functional Communication Measures (FCMs) and an adapted motor speech disorder (MSD) severity rating. Method Speech and language evaluations were completed for 24 patients with progressive AOS (n = 7 with isolated AOS; n = 17 with a combination of AOS and aphasia). Descriptive comparisons were utilized to evaluate differences in communication measures among patients with various combinations of MSDs and aphasia. Differences associated with phonetic predominant or prosodic predominant AOS were also examined. Across the entire cohort, correlations were calculated between the participation ratings and other clinical assessment measures. Results The CPIB reflected greater limitations for those with aphasia and AOS compared to isolated AOS, but was not notably different when dysarthria occurred with AOS (n = 9/24). Across the cohort, there were statistically significant correlations between the CPIB and ASHA FCM-Motor Speech and Language Expression ratings and the MSD severity rating. The CPIB did not correlate with the ASHA FCM-Language Comprehension or other speech-language measures. Conclusions Patients with neurodegenerative AOS experience reduced participation in communication that is further exacerbated by co-occurring language deficits. The study suggests measures of severity cannot be assumed to correlate with measures of participation restrictions and offers a foundation for further research examining the day-to-day sequela of progressive speech and language disorders. Supplemental Material https://doi.org/10.23641/asha.12743252.

Language and Speech Markers of Primary Progressive Aphasia: A Systematic Review

Purpose This systematic review aimed to establish language and speech markers to support the clinical diagnosis of primary progressive aphasia (PPA) and its clinical phenotypes. Our first objective was to identify behavioral language and speech markers of early-stage PPA. Our second objective was to identify the electrophysiological correlates of the language and speech characteristics in PPA. Method The databases MEDLINE, Web of Science, and Embase were searched for relevant articles. To identify behavioral markers, the initial subjective complaints and the language and speech deficits detected during the initial diagnostic evaluation were summarized for PPA in general and each clinical variant according to the 2011 consensus diagnostic criteria (nonfluent variant [NFV], semantic variant, and logopenic variant [LV]). To identify electrophysiological markers, the studies in which event-related potentials (ERPs) were elicited by a language or speech paradigm in patients with PPA were included. Results In total, 114 relevant studies were identified, including 110 behavioral studies and only four electrophysiological studies. This review suggests that patients with the semantic variant could be accurately differentiated from the NFV and LV in the initial stages based on the consensus criteria. Nonetheless, the early differentiation between the NFV and LV is not straightforward. In the four electrophysiological studies, differences in the latency, amplitude, and topographical distribution of the semantic N400 component were found between patients with PPA and healthy controls. Conclusions To accurately differentiate the NFV from the LV, it could be important to assess the language and speech degeneration by more specific assessments and by more objective diagnostic methods that offer insights into the language-related processes. Electrophysiological markers of PPA were not identified in this review due to the low number of studies that investigated language-related ERPs. More controlled ERP studies in larger patient cohorts are needed to investigate the diagnostic applicability of language-related ERPs in PPA. Supplemental Material https://doi.org/10.23641/asha.12798080.

Clinical Features of Late-onset Semantic Dementia

BACKGROUND

Semantic dementia (SD) is characterized by progressive semantic anomia extending to a multimodal loss of semantic knowledge. Although often considered an early-onset dementia, SD also occurs in later life, when it may be misdiagnosed as Alzheimer disease (AD).

OBJECTIVE

To evaluate late-onset SD in comparison to early-onset SD and to AD.

METHODS

We identified 74 individuals with SD and then compared those with late-onset SD (≥65 years of age) to those with early-onset SD (<65) on demographic and clinical features. We also compared a subgroup of 23 of the late-onset SD individuals with an equal number of individuals with clinically probable AD.

RESULTS

Twenty-six (35.1%) of the SD individuals were late onset, and 48 (64.9%) were early onset. There were no differences between the two groups on clinical measures, although greater asymmetry of temporal involvement trended to significance in the late-onset SD group. Compared to the 23 AD individuals, the subgroup of 23 late-onset SD individuals had worse performance on confrontational naming, irregular word reading, and face recognition; however, this subgroup displayed better verbal delayed recall and constructions. The late-onset SD individuals also experienced early personality changes at a time when most individuals with AD had not yet developed behavioral changes.

CONCLUSIONS

Approximately one-third of SD individuals may be late onset, and the differentiation of late-onset SD from AD can lead to better disease management, education, and prognosis. SD may be distinguished by screening for disproportionate changes in reading, face recognition, and personality.

Primary Progressive Apraxia of Speech: From Recognition to Diagnosis and Care

BACKGROUND

Apraxia of speech (AOS) can be caused by neurodegenerative disease and sometimes is its presenting sign (i.e., primary progressive apraxia of speech, PPAOS). During the last several decades our understanding of PPAOS has evolved from clinical recognition to a fuller understanding of its core and associated clinical features, its distinction from but relationship with primary progressive aphasia, its temporal course and eventual progression to include other neurological deficits, and its neuroimaging correlates and underlying pathology.

AIMS

This paper provides a comprehensive summary of the literature that has built the current knowledge base about PPAOS and progressive AOS as it co-occurs with progressive aphasia. It reviews the history of its emergence as a recognized syndrome; its relationship with the agrammatic/nonfluent variant of primary progressive aphasia; its salient perceptual features and subtypes; the acoustic and structural/physiological imaging measures that index its presence, severity, and distinction from aphasia; and principles and available data regarding its management and care.

MAIN CONTRIBUTION

A broad summary of what is known about AOS as a manifestation of neurodegenerative disease.

CONCLUSIONS

Primary progressive apraxia of speech is a recognizable syndrome that can be distinguished from other neurodegenerative conditions that affect speech and language.

Non-fluent/Agrammatic Variant of Primary Progressive Aphasia With Generalized Auditory Agnosia

Cortical neurodegeneration-induced non-fluent/agrammatic variant of primary progressive aphasia (nfvPPA) is a clinical syndrome characterized by non-fluent speech, such as apraxia of speech or agrammatism. We describe the case of an 80-year-old right-handed woman who exhibited nfvPPA. Atypically, our patient also presented with generalized auditory agnosia. Brain magnetic resonance imaging revealed left-sided predominant atrophy of the bilateral perisylvian area, including the inferior frontal and superior temporal lobes. In a series of auditory tasks assessing generalized auditory agnosia, our patient was unable to accurately identify verbal sounds, environmental sounds, or familiar Japanese songs that she could sing. In the context of recent studies, our study indicates the existence of a clinical syndrome characterized by progressive speech disorder with auditory agnosia. This case report thus provides novel insights into the spectrum of language impairment induced by neurodegenerative disease.