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Frontotemporal dementia (FTD) is among the most common forms of dementia, with an average symptom onset in the fifth decade of life. Neuropathologic changes in FTD demonstrate degeneration in the frontal and/or temporal lobes, which is defined as frontotemporal lobar degeneration (FTLD). FTD is categorized into a subset of variants by symptomatic presentation and corresponding clinical workup. Primary progressive aphasia (PPA) is among these variants of FTD and is distinguished by its primary clinical presentation of language impairment with correlating neuropathology in the aforementioned areas of the brain. More specifically, the classification of PPA is further subdivided into three clinical variants, which has allowed for appropriate diagnostic and prognostic considerations within this patient population. Among these variants in PPA are the semantic (svPPA), non-fluent (navPPA), and logopenic (lvPPA) forms. Motor neuron disease (MND) is a progressive and irreversible process of neuronal degeneration that can lead to an upper motor neuron, a lower motor neuron, or a combination of these two symptomologies. FTD and its association with MND is a well-established spectrum, although more rarely among the PPA variant of FTD. Comparatively, there is a significant body of clinical knowledge on the association between the behavioral variant of FTD (bvFTD) and MND. This is the case of a 69-year-old female with navPPA who later presented with clinical symptoms of MND. Although the two clinical diagnoses, PPA and MND, are irreversible and progressive, this case serves to elucidate diagnostic and prognostic considerations in this rare patient population.

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Analysing spontaneous speech in individuals experiencing fluency difficulties holds potential for diagnosing speech and language disorders, including Primary Progressive Aphasia (PPA). Dysfluency in the spontaneous speech of patients with PPA has mostly been described in terms of abnormal pausing behaviour, but the temporal features related to speech have drawn little attention. This study compares speech-related fluency parameters in the three main variants of PPA and in typical speech. Forty-three adults participated in this research, thirteen with the logopenic variant of PPA (lvPPA), ten with the non-fluent variant (nfvPPA), nine with the semantic variant (svPPA), and eleven who were healthy age-matched adults. Participants' fluency was assessed through a picture description task from which 42 parameters were computed including syllable duration, speaking pace, the duration of speech chunks (i.e. interpausal units, IPU), and the number of linguistic units per IPU and per second. The results showed that each PPA variant exhibited abnormal speech characteristics reflecting various underlying factors, from motor speech deficits to higher-level issues. Out of the 42 parameters considered, 37 proved useful for characterising dysfluency in the three main PPA variants and 35 in distinguishing among them. Therefore, taking into account not only pausing behaviour but also temporal speech parameters can provide a fuller understanding of dysfluency in PPA. However, no single parameter by itself sufficed to distinguish one PPA group from the other two, further evidence that dysfluency is not dichotomous but rather multidimensional, and that complementary multiparametric analyses are needed.

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The presence of parkinsonism features in primary progressive aphasia (PPA) is a subject of ongoing research. These features are usually more pronounced in the advanced stages of the disease, particularly in the non-fluent/agrammatic subtype, and are exceptionally rare in the logopenic variant (lvPPA). Here we report a case of a 63-year-old man presenting as language impairment, predominantly naming and word-finding difficulties, emerged alongside a left-sided internal tremor. Neurological examination revealed bilateral, left-side predominant rigidity, bradykinesia, and resting tremor. Notably, anosmia and constipation were present. Language assessments showed preserved single-word comprehension, object knowledge, and a minimal apraxia of speech, as well as sentence repetition issues. Neuroimaging and biomarker analysis supported a diagnosis of primary progressive logopenic aphasia with amyloid pathology co-existing with prominent and early parkinsonism. This case underlines the intricate relationship between language disorders, parkinsonism, and amyloid pathology in lvPPA.

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INTRODUCTION: Mounting evidence indicates distinct memory profiles among the primary progressive aphasia (PPA) variants. Neuropsychological tests reveal disproportionate memory impairments in the logopenic variant PPA (lv-PPA) relative to the non-fluent variant PPA (nfv-PPA) and semantic variant PPA (sv-PPA). The real-world experience of day-to-day memory disturbances in PPA, however, remains poorly understood. METHODS: Everyday expressions of memory in 26 lv-PPA, 24 nfv-PPA, and 40 sv-PPA patients, and 70 healthy controls were examined using the Cambridge Behavioural Inventory-Revised (CBI-R) carer questionnaire. Kruskal-Wallis tests compared CBI-R Memory items (1-8) across groups. Receiver operating characteristic curves evaluated the most discriminative items to distinguish lv-PPA from nfv-PPA. RESULTS: Compared to controls, lv-PPA and sv-PPA patients were reported to experience more day-to-day memory issues (item 1), increased repetition of questions (2), forgetting the names of familiar people and objects (4, 5), and poor concentration (6). lv-PPA patients were also reported to exhibit more occurrences of losing or misplacing items (3) and forgetting the day (7). All PPA groups experienced more confusion in unfamiliar environments (8) than controls. Direct comparisons among PPA groups revealed distinct profiles, with lv-PPA and sv-PPA patients exhibiting more frequent forgetting of names and objects (3, 4) than nfv-PPA, and sv-PPA demonstrating greater day-to-day memory impairment (1), repeated questions (2), and poor concentration (6) compared to nfv-PPA. Forgetting the names of familiar objects (5) was the most sensitive and specific item to distinguish lv-PPA from nfv-PPA. CONCLUSIONS: Our findings demonstrate distinct day-to-day memory profiles in PPA. Future research should explore the influence of language impairments on these profiles.

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Primary progressive aphasia (PPA) describes a group of language-led dementias. Speech and language therapy is the main available intervention for people with PPA. Despite best practice recommendations for speech and language therapy to include access to group therapies (Volkmer et al, 2023a), research evidence to date has predominantly focused on delivery in individual sessions. The aim of this study was to gather the collective intelligence of expert speech and language therapists/pathologists delivering group therapy for people with PPA to synthesize guidance for clinicians. This paper describes a qualitative study using narrative synthesis methods. Data were collected using the Template for Intervention Description and Replication - TIDiER. Eight respondents described a total of 17 different groups. Respondents worked across healthcare, research clinics and third sector organizations in Australia, Canada, Spain, the USA and the UK. For the purposes of analysis, groups were divided into two main types: (1) groups delivering specific therapy interventions; and (2) groups providing broader opportunities for conversational practice and support. This initial synthesis of the current state of the art in PPA therapy groups highlights several important considerations around candidacy, content and ecological validity of delivering group intervention for people with PPA.

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Primary progressive aphasia (PPA) is a neurodegenerative brain disorder characterized by declining language ability. It is a rare, often young-onset dementia with a devastating impact on the work and personal activities of those affected. At present there is no cure or disease-modifying therapy for PPA nor any way to arrest or slow the underlying progressive brain degeneration. Throughout the course of the condition any treatment must therefore be palliative-designed to manage symptoms and improve the quality of life of the affected person. The majority of those affected receive little or no follow-up care after diagnosis, particularly in the early stage of the disease. There is very little information in the medical literature about person-centered care designed to improve the quality of life of people with PPA written from the perspective of those living with this condition. I received an early and accurate clinical diagnosis of the nonfluent/agrammatic variant of PPA, supported by imaging. I am fortunate to have benefited from exemplary individualized care from a multidisciplinary medical team from the onset of my difficulties with language. In this paper, I discuss my lived experience of all aspects of this personalized and person-centered care, describing how it was founded on shared decision-making and a holistic, dementia-inclusive approach encompassing the physical, mental, emotional, psychosocial and spiritual dimensions of living with an incurable neurodegenerative disease.

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BACKGROUND: Traumatic brain injury (TBI) and repetitive head impacts (RHI) have been linked to increased risk for multiple types of neurodegenerative disease, higher dementia risk, and earlier age of dementia symptom onset, suggesting transdiagnostic implications for later-life brain health. Frontotemporal dementia (FTD) and primary progressive aphasia (PPA) represent a spectrum of clinical phenotypes that are neuropathologically diverse. FTD/PPA diagnoses bring unique challenges due to complex cognitive and behavioral symptoms that disproportionately present as an early-onset dementia (before age 65). We performed a detailed characterization of lifetime head trauma exposure in individuals with FTD and PPA compared to healthy controls to examine frequency of lifetime TBI and RHI and associated clinical implications. METHODS: We studied 132 FTD/PPA (age 68.9 ± 8.1, 65% male) and 132 sex-matched healthy controls (HC; age 73.4 ± 7.6). We compared rates of prior TBI and RHI (contact/collision sports) between FTD/PPA and HC (chi-square, logistic regression, analysis of variance). Within FTD/PPA, we evaluated associations with age of symptom onset (analysis of variance). Within behavioral variant FTD, we evaluated associations with cognitive function and neuropsychiatric symptoms (linear regression controlling for age, sex, and years of education). RESULTS: Years of participation were greater in FTD/PPA than HC for any contact/collision sport (8.5 ± 6.7yrs vs. 5.3 ± 4.5yrs, p = .008) and for American football (6.2yrs ± 4.3yrs vs. 3.1 ± 2.4yrs; p = .003). Within FTD/PPA, there were dose-dependent associations with earlier age of symptom onset for TBI (0 TBI: 62.1 ± 8.1, 1 TBI: 59.9 ± 6.9, 2 + TBI: 57.3 ± 8.4; p = .03) and years of American football (0yrs: 62.2 ± 8.7, 1-4yrs: 59.7 ± 7.0, 5 + yrs: 55.9 ± 6.3; p = .009). Within bvFTD, those who played American football had worse memory (z-score: -2.4 ± 1.2 vs. -1.4 ± 1.6, p = .02, d = 1.1). CONCLUSIONS: Lifetime head trauma may represent a preventable environmental risk factor for FTD/PPA. Dose-dependent exposure to TBI or RHI influences FTD/PPA symptom onset and memory function in bvFTD. Clinico-pathological studies are needed to better understand the neuropathological correlates linking RHI or TBI to FTD/PPA onset and symptoms.

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(1) Background: Frontotemporal lobar degeneration (FTLD) is a generic term which refers to multiple pathologies, including FTLD-tau. The most common FTLD-tau diseases are Pick's disease (PiD), progressive supranuclear palsy (PSP) and corticobasal degeneration (CBD). These diseases share four major syndromes: behavioral variant frontotemporal dementia (bvFD), Richardson syndrome (RS), corticobasal syndrome (CBS) and non-fluent agrammatic primary progressive aphasia (nfa-PPA). The primary aim of this meta-analysis was to examine the diagnostic performance of CSF total (t-tau) and phosphorylated (p-tau) protein in bvFTD, RS, CBS, nfa-PPA and pathologically or genetically defined tauopathy. (2) Methods: A systematic review and meta-analysis was performed on all studies with >10 subjects in a bvFTD/RS/CBS/nfa-PPA group and control group and available data on CSF t-tau or p-tau (mean, SD). Cohen's d was used to quantify the effect size of each study (3) Results: The PSP/tauopathy patients exhibited decreased levels of CSF p-tau compared to the control subjects. The CBS/bvFTD/nfa-PPA cohorts exhibited an increase in t-tau compared to the control groups. (4) Conclusions: Tauopathies may exhibit an inherent decrease in CSF p-tau. The admixture of AD patients in FTD cohorts and high heterogeneity among studies on rare diseases are significant confounding factors in FTLD studies.

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Primary progressive aphasia (PPA) is a disease known to affect the frontal and temporal regions of the left hemisphere. PPA is often an indication of future development of dementia, specifically semantic dementia (SD) for frontotemporal dementia (FTD) and logopenic progressive aphasia (LPA) as an atypical presentation of Alzheimer's disease (AD). The purpose of this review is to clarify the value of 2-deoxy-2-[18F]fluoro-D-glucose (FDG)-positron emission tomography (PET) in the detection and diagnosis of PPA. A comprehensive review of literature was conducted using Web of Science, PubMed, and Google Scholar. The three PPA subtypes show distinct regions of hypometabolism in FDG-PET imaging with SD in the anterior temporal lobes, LPA in the left temporo-parietal junction, and nonfluent/agrammatic Variant PPA (nfvPPA) in the left inferior frontal gyrus and insula. Despite the distinct patterns, overlapping hypometabolic areas can complicate differential diagnosis, especially in patients with SD who are frequently diagnosed with AD. Integration with other diagnostic tools could refine the diagnostic process and lead to improved patient outcomes. Future research should focus on validating these findings in larger populations and exploring the therapeutic implications of early, accurate PPA diagnosis with more targeted therapeutic interventions.

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Clinical variants of Alzheimer's disease and frontotemporal lobar degeneration display a spectrum of cognitive-behavioural changes varying between individuals and over time. Understanding the landscape of these graded individual-/group-level longitudinal variations is critical for precise phenotyping; however, this remains challenging to model. Addressing this challenge, we leverage the National Alzheimer's Coordinating Center database to derive a unified geometric framework of graded longitudinal phenotypic variation in Alzheimer's disease and frontotemporal lobar degeneration. We included three time-point, cognitive-behavioural and clinical data from 390 typical, atypical and intermediate Alzheimer's disease and frontotemporal lobar degeneration variants (114 typical Alzheimer's disease; 107 behavioural variant frontotemporal dementia; 42 motor variants of frontotemporal lobar degeneration; and 103 primary progressive aphasia patients). On this data, we applied advanced data-science approaches to derive low-dimensional geometric spaces capturing core features underpinning clinical progression of Alzheimer's disease and frontotemporal lobar degeneration syndromes. To do so, we first used principal component analysis to derive six axes of graded longitudinal phenotypic variation capturing patient-specific movement along and across these axes. Then, we distilled these axes into a visualisable 2D manifold of longitudinal phenotypic variation using Uniform Manifold Approximation and Projection. Both geometries together enabled the assimilation and inter-relation of paradigmatic and mixed cases, capturing dynamic individual trajectories, and linking syndromic variability to neuropathology and key clinical end-points such as survival. Through these low-dimensional geometries, we show that (i) specific syndromes (Alzheimer's disease and primary progressive aphasia) converge over time into a de-differentiated pooled phenotype, while others (frontotemporal dementia variants) diverge to look different from this generic phenotype; (ii) phenotypic diversification is predicted by simultaneous progression along multiple axes, varying in a graded manner between individuals and syndromes; and (iii) movement along specific principal axes predicts survival at 36 months in a syndrome-specific manner and in individual pathological groupings. The resultant mapping of dynamics underlying cognitive-behavioural evolution potentially holds paradigm-changing implications to predicting phenotypic diversification and phenotype-neurobiological mapping in Alzheimer's disease and frontotemporal lobar degeneration.

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BACKGROUND AND PURPOSE: Dysphagia is an important feature of neurodegenerative diseases and potentially life-threatening in primary progressive aphasia (PPA) but remains poorly characterized in these syndromes. We hypothesized that dysphagia would be more prevalent in nonfluent/agrammatic variant (nfv)PPA than other PPA syndromes, predicted by accompanying motor features, and associated with atrophy affecting regions implicated in swallowing control. METHODS: In a retrospective case-control study at our tertiary referral centre, we recruited 56 patients with PPA (21 nfvPPA, 22 semantic variant [sv]PPA, 13 logopenic variant [lv]PPA). Using a pro forma based on caregiver surveys and clinical records, we documented dysphagia (present/absent) and associated, potentially predictive clinical, cognitive, and behavioural features. These were used to train a machine learning model. Patients' brain magnetic resonance imaging scans were assessed using voxel-based morphometry and region-of-interest analyses comparing differential atrophy profiles associated with dysphagia presence/absence. RESULTS: Dysphagia was significantly more prevalent in nfvPPA (43% vs. 5% svPPA and no lvPPA). The machine learning model revealed a hierarchy of features predicting dysphagia in the nfvPPA group, with excellent classification accuracy (90.5%, 95% confidence interval = 77.9-100); the strongest predictor was orofacial apraxia, followed by older age, parkinsonism, more severe behavioural disturbance, and more severe cognitive impairment. Significant grey matter atrophy correlates of dysphagia in nfvPPA were identified in left middle frontal, right superior frontal, and right supramarginal gyri and right caudate. CONCLUSIONS: Dysphagia is a common feature of nfvPPA, linked to underlying corticosubcortical network dysfunction. Clinicians should anticipate this symptom particularly in the context of other motor features and more severe disease.

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Persons with primary progressive aphasia (PPA) often experience limitations in their quality of life (QoL). Some studies have shown positive effects of speech and language therapy on QoL in persons with PPA. However, there is still a lack of evidence for disorder-specific approaches for this important therapeutic goal. The biographic-narrative approach (narraktiv) has been shown to significantly improve QoL in persons with post-stroke aphasia. In the planned study, the biographic-narrative approach will be adapted for persons with PPA (Cope PPA), and its efficacy will be investigated. First, a focus group interview with five persons with PPA will be conducted to identify the wishes and needs of participants. Based on the results, the narraktiv manual according to Corsten et al. (2015) will be revised. Second, an efficacy study will be conducted according to the new Cope PPA manual with 24 persons with PPA in a waiting group control design. The primary outcome, QoL, will be assessed using questionnaires (Stroke and Aphasia Quality of Life Scale-39) and semistructured interviews. Depressive symptoms, life satisfaction and cognitive/communicative functioning will also be assessed. If Cope PPA proves efficacy, this study may help to improve the treatment of persons with PPA.

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Some patients with primary progressive aphasia (PPA) demonstrate only anomia. The lack of longitudinal observations of anomic PPA precluded us from determining whether progressive anomic aphasia was simply an early stage of semantic or logopenic variants, or a relatively independent variant. Herein, we report the 10-year clinical course of a patient with PPA who presented with pure anomic aphasia for 9 years. He is a right-handed man with anomia, who noticed word-finding difficulty at age 73. He was admitted to the hospital at age 77. On admission, the patient showed pure anomic aphasia with preserved other language function. Episodic memory and visuospatial function were preserved. Magnetic resonance imaging (MRI) revealed left temporal lobe atrophy. At 82 years of age, the patient presented with pure anomic aphasia. At 83 years old, he showed mild impairment in word comprehension and semantic memory, in addition to anomia. MRI demonstrated further atrophy in the bilateral anterior temporal lobes, predominantly on the left side. This case suggests the possibility of slowly progressive, late-onset anomic PPA, which could be differentiated from the early stage of semantic or logopenic variants.

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The WHO Dementia Global Action Plan states that rehabilitation services for dementia are required to promote health, reduce disability, and maintain quality of life for those living with dementia. Current services, however, are scarce, particularly for people with young-onset dementia (YOD). This article, written by an international group of multidisciplinary dementia specialists, offers a three-part overview to promote the development of rehabilitation services for YOD. Firstly, we provide a synthesis of knowledge on current evidence-based rehabilitative therapies for early-onset Alzheimer's disease (EOAD), behavioural variant frontotemporal dementia (bvFTD), primary progressive aphasia (PPA), and posterior cortical atrophy (PCA). Secondly, we discuss the characteristics of rehabilitation services for YOD, providing examples across three continents for how these services can be embedded in existing settings and the different roles of the rehabilitation multidisciplinary team. Lastly, we conclude by highlighting the potential of telehealth in making rehabilitation services more accessible for people with YOD. Overall, with this paper, we aim to encourage clinical leads to begin introducing at least some rehabilitation into their services, leveraging existing resources and finding support in the collective expertise of the broader multidisciplinary dementia professional community.

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Multiple pharmacologic agents now have been approved in the United States and other countries as treatment to slow disease and clinical progression for Alzheimer's disease. Given these treatments have not been proven to lessen the cognitive deficits already manifested in the Alzheimer's Clinical Syndrome (ACS), and none are aimed for another debilitating dementia syndrome identified as primary progressive aphasia (PPA), there is an urgent need for new, safe, tolerable, and efficacious treatments to mitigate the cognitive deficits experienced in ACS and PPA. Noninvasive brain stimulation has shown promise for enhancing cognitive functioning, and there has been interest in its potential therapeutic value in ACS and PPA. This review critically examines the evidence of five technologies in ACS and PPA: transcranial direct current stimulation (tDCS), transcranial alternating current stimulation (tACS), transcranial random noise stimulation (tRNS), repetitive transcranial magnetic stimulation (rTMS), and noninvasive vagus nerve stimulation (nVNS). Many randomized controlled trials of tDCS and rTMS report positive treatment effects on cognition in ACS and PPA that persist out to at least 8 weeks, whereas there are few trials for tACS and none for tRNS and nVNS. However, most positive trials did not identify clinically meaningful changes, underscoring that clinical efficacy has yet to be established in ACS and PPA. Much is still to be learned about noninvasive brain stimulation in ACS and PPA, and shifting the focus to prioritize clinical significance in addition to statistical significance in trials could yield greater success in understanding its potential cognitive effects and optimal parameters.

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BACKGROUND: Speech and language therapists (SLTs) play an important role in assessing and rehabilitating communication disorders in people with dementia, but there is evidence to suggest that they do not receive appropriate training to provide management and support during their training. AIM: To investigate the level of awareness and knowledge that practising SLTs from Brazil have about dementia and their role in the care of dementia through an online survey. METHODS & PROCEDURES: An online survey tool was developed to collect information from practising Brazilian SLTs regarding their knowledge about dementia, awareness about their role in the care of people with dementia, and opinions on how SLTs may be better prepared to work in the dementia field. The survey was disseminated via social media, websites, and e-mail lists of researchers and stakeholders. OUTCOMES & RESULTS: A total of 227 SLTs completed the survey. Participants showed good knowledge of dementia in general, while their answers were less accurate on primary progressive aphasia. Regarding the awareness by SLTs of their role in the care of people with dementia, most agreed or strongly agreed that SLTs could help people in the diagnosis, treatment and prevention of dementia (> 80%). However, fewer participants agreed or strongly agreed that they felt confident in contributing to the treatment and diagnosis process of dementia (about 50%). To improve the training of SLTs in Brazil, most participants believed that it would be necessary to improve the teaching of dementia at the undergraduate speech and language therapy curriculum level and to develop recommendations or guidelines about speech and language therapy practice in dementia. CONCLUSIONS & IMPLICATIONS: The results of this survey point to a need for improvement in the knowledge and confidence of Brazilian SLTs about dementia. To reach this goal, targeted training courses and applied practice opportunities should be embedded within university curricula and training programmes. WHAT THIS PAPER ADDS: What is already known on the subject Many studies confirm the importance of speech and language therapy in the non-pharmacological treatment of people with dementia. However, other evidence suggests to a possible lack of training for Brazilian SLTs, especially in the curriculum of undergraduate courses. What this paper adds to existing knowledge This study reveals that Brazilian SLTs have substantial knowledge of dementia and recognize the significance of their role in treating people with dementia. However, a minority expressed confidence in their ability to assess and treat people with dementia. What are the potential or actual clinical implications of this work? The findings of this research demonstrate that Brazilian SLTs have good knowledge of dementia and endorse their professional role in dementia care; however, they lack confidence in their own skills and expertise in diagnostic assessment and treatment of dementia. Interventions aimed at boosting the SLT's confidence level could lead to improved patients outcomes and overall quality of care within clinical settings.

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Semantic dementia is a kind of neurodegenerative disorder, characterized by prominent semantic impairments and anterior temporal lobe atrophy. Since 2010, more studies have devoted to this rare disorder, revealing that it is more complex than we think. Clinical advances include more specific findings of semantic impairments and other higher order cognitive deficits. Neuroimaging techniques can help revealing the different brain networks affected (both structurally and functionally) in this condition. Pathological and genetic studies have also found more complex situations of semantic dementia, which might explain the huge variance existing in semantic dementia. Moreover, the current diagnosis criteria mainly focus on semantic dementia's classical prototype. We further delineated the features of three subtypes of semantic dementia based on atrophy lateralization with three severity stages. In a broader background, as a part of the continuum of neurodegenerative disorders, semantic dementia is commonly compared with other resembling conditions. Therefore, we summarized the differential diagnosis between semantic dementia and them. Finally, we introduced the challenges and achievements of its diagnosis, treatment, care and cross cultural comparison. By providing a comprehensive picture of semantic dementia on different aspects of advances, we hope to deepen the understanding of semantic dementia and promote more inspirations on both clinical and theoretical studies about it.

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Neurodegenerative dementia syndromes, such as primary progressive aphasias (PPA), have traditionally been diagnosed based, in part, on verbal and non-verbal cognitive profiles. Debate continues about whether PPA is best divided into three variants and regarding the most distinctive linguistic features for classifying PPA variants. In this cross-sectional study, we initially harnessed the capabilities of artificial intelligence and natural language processing to perform unsupervised classification of short, connected speech samples from 78 pateints with PPA. We then used natural language processing to identify linguistic features that best dissociate the three PPA variants. Large language models discerned three distinct PPA clusters, with 88.5% agreement with independent clinical diagnoses. Patterns of cortical atrophy of three data-driven clusters corresponded to the localization in the clinical diagnostic criteria. In the subsequent supervised classification, 17 distinctive features emerged, including the observation that separating verbs into high- and low-frequency types significantly improved classification accuracy. Using these linguistic features derived from the analysis of short, connected speech samples, we developed a classifier that achieved 97.9% accuracy in classifying the four groups (three PPA variants and healthy controls). The data-driven section of this study showcases the ability of large language models to find natural partitioning in the speech of patients with PPA consistent with conventional variants. In addition, the work identifies a robust set of language features indicative of each PPA variant, emphasizing the significance of dividing verbs into high- and low-frequency categories. Beyond improving diagnostic accuracy, these findings enhance our understanding of the neurobiology of language processing.

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In addition to Alzheimer's disease (AD), the hippocampus is now known to be affected in variants of frontotemporal degeneration (FTD). In semantic variant primary progressive aphasia (svPPA), characterized by language impairments, hippocampal atrophy is greater in the left hemisphere. Nonverbal impairments (e.g., visual object recognition) are prominent in the right temporal variant of FTD (rtvFTD), and hippocampal atrophy may be greater in the right hemisphere. In this study we examined the hypothesis that leftward hippocampal asymmetry (predicted in svPPA) would be associated with selective verbal memory impairments (with relative preservation of visual memory), while rightward asymmetry (predicted in rtvFTD) would be associated with the opposite pattern (greater visual memory impairment). In contrast, we predicted that controls and individuals in the amnestic mild cognitive impairment stage of AD (aMCI), both of whom were expected to show symmetrical hippocampal volumes, would show roughly equivalent scores in verbal and visual memory. Participants completed delayed recall tests with words and geometric shapes, and hippocampal volumes were assessed with MRI. The aMCI sample showed symmetrical hippocampal atrophy, and similar degree of verbal and visual memory impairment. The svPPA sample showed greater left hippocampal atrophy and verbal memory impairment, while rtvFTD showed greater right hippocampal atrophy and visual memory impairment. Greater asymmetry in hippocampal volumes was associated with larger differences between verbal and visual memory in the FTD samples. Unlike AD, asymmetry is a core feature of brain-memory relationships in temporal variants of FTD.

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BACKGROUND: Communication disabilities, such as primary progressive aphasia (PPA), impact family members as well as the individuals with the condition. To provide adequate communication care to people with PPA (PwPPA) and their family members, it is crucial to understand the communication needs from the family members' perspectives. To date, research on the communication needs of people with primary progressive aphasia and their family members from the perspectives of family members has been limited. AIMS: The specific research objectives were to explore (a) the communication needs pertaining to PwPPA in the early, middle and late stages; and (b) the communication needs pertaining to family members of PwPPA in the early, middle and late stages, from the perspectives of family members. METHODS & PROCEDURES: This study employed a qualitative description approach, underpinned by the pragmatic paradigm. Data collection involved semi-structured qualitative interviews with eight family members (relatives of four individuals with the logopenic variant of PPA, of two individuals with the nonfluent variant of PPA, of one individual with the semantic variant of PPA and of one individual with mixed PPA). Qualitative content analysis was used to identify codes and categories in relation to the research objectives. OUTCOMES & RESULTS: Qualitative content analysis revealed eight categories of communication needs pertaining to the PwPPA: person-specific needs; diagnosis and disclosure; general communication difficulties; impact on communication in everyday life; impact on cognition; impact on psychosocial well-being; impact on person's dignity and autonomy; and future planning. Six categories were identified pertaining to the family members: information about and awareness of PPA; impact of communication difficulties on family/others; increased responsibilities for the family in everyday life; impact on psychosocial well-being; and future planning. CONCLUSIONS & IMPLICATIONS: This investigation has expanded our knowledge in the area by providing insights about communication needs which speech-language pathologists and other health professionals should be aware of and take into account when providing communication care to PwPPA and their families. WHAT THIS PAPER ADDS: What is already known on the subject Person- and family-centred communication care is optimally guided by the person's and family's needs and values. Research on communication care for people with primary progressive aphasia has underscored the inclusion of family members. Previous research has investigated the impact and experiences of living with primary progressive aphasia from the family member perspective. What this paper adds to existing knowledge To date, research focusing on identifying the communication needs of people with primary progressive aphasia and their family members from the perspective of family members is limited. This study adds the family members' perspectives on the communication needs pertaining to themselves and their relatives with primary progressive aphasia in the early, middle and late stages of primary progressive aphasia. What are the potential or clinical implications of this work? Several clinical implications have been raised. Family members experience communication needs for themselves and should be included as recipients of communication care. Clinicians supporting people with primary progressive aphasia should be cognizant of the impact of communication fatigue on everyday life and therapy tasks. Communication care for this population should include communication partner training, support for psychosocial well-being and support with communication around future planning.