A neuroanatomical and cognitive model of impaired social behaviour in frontotemporal dementia.

Impaired social cognition is a core deficit in frontotemporal dementia (FTD). It is most commonly associated with the behavioural-variant of FTD, with atrophy of the orbitofrontal and ventromedial prefrontal cortex. Social cognitive changes are also common in semantic dementia, with atrophy centred on the anterior temporal lobes. The impairment of social behaviour in FTD has typically been attributed to damage to the orbitofrontal cortex and/or temporal poles and/or the uncinate fasciculus that connects them. However, the relative contributions of each region are unresolved. In this review, we present a unified neurocognitive model of controlled social behaviour that not only explains the observed impairment of social behaviours in FTD, but also assimilates both consistent and potentially contradictory findings from other patient groups, comparative neurology and normative cognitive neuroscience. We propose that impaired social behaviour results from damage to two cognitively- and anatomically-distinct components. The first component is social-semantic knowledge, a part of the general semantic-conceptual system supported by the anterior temporal lobes bilaterally. The second component is social control, supported by the orbitofrontal cortex, medial frontal cortex and ventrolateral frontal cortex, which interacts with social-semantic knowledge to guide and shape social behaviour.

Atrophy network mapping of clinical subtypes and main symptoms in frontotemporal dementia.

Frontotemporal dementia (FTD) is a disease of high heterogeneity, apathy and disinhibition present in all subtypes of FTD and imposes a significant burden on families/society. Traditional neuroimaging analysis has limitations in elucidating the network localization due to individual clinical and neuroanatomical variability. The study aims to identify the atrophy network map associated with different FTD clinical subtypes and determine the specific localization of the network for apathy and disinhibition. Eighty FTD patients [45 behavioural variant FTD (bvFTD) and 35 semantic variant progressive primary aphasia (svPPA)] and 58 healthy controls at Xuanwu Hospital were enrolled as Dataset 1; 112 FTD patients including 50 bvFTD, 32 svPPA and 30 non-fluent variant PPA (nfvPPA) cases, and 110 healthy controls from the Frontotemporal Lobar Degeneration Neuroimaging Initiative (FTLDNI) dataset were included as Dataset 2. Initially, single-subject atrophy maps were defined by comparing cortical thickness in each FTD patient versus healthy controls. Next, the network of brain regions functionally connected to each FTD patient's location of atrophy was determined using seed-based functional connectivity in a large (n = 1000) normative connectome. Finally, we used atrophy network mapping to define clinical subtype-specific network (45 bvFTD, 35 svPPA and 58 healthy controls in Dataset 1; 50 bvFTD, 32 svPPA, 30 nfvPPA and 110 healthy controls in Dataset 2) and symptom-specific networks [combined Datasets 1 and 2, apathy without depression versus non-apathy without depression (80:26), disinhibition versus non-disinhibition (88:68)]. We compare the result with matched symptom networks derived from patients with focal brain lesions or conjunction analysis. Through the analysis of two datasets, we identified heterogeneity in atrophy patterns among FTD patients. However, these atrophy patterns are connected to a common brain network. The primary regions affected by atrophy in FTD included the frontal and temporal lobes, particularly the anterior temporal lobe. bvFTD connects to frontal and temporal cortical areas, svPPA mainly impacts the anterior temporal region and nfvPPA targets the inferior frontal gyrus and precentral cortex regions. The apathy-specific network was localized in the orbital frontal cortex and ventral striatum, while the disinhibition-specific network was localized in the bilateral orbital frontal gyrus and right temporal lobe. Apathy and disinhibition atrophy networks resemble known motivational and criminal lesion networks, respectively. A significant correlation was found between the apathy/disinhibition scores and functional connectivity between atrophy maps and the peak of the networks. This study localizes the common network of clinical subtypes and main symptoms in FTD, guiding future FTD neuromodulation interventions.

Describing and assessing behavioural symptoms in amyotrophic lateral sclerosis with and without frontotemporal dementia: a scoping review.

PURPOSE OF REVIEW: Alongside motor and cognitive symptoms, amyotrophic lateral sclerosis (ALS) and ALS with frontotemporal dementia (ALSFTD) present with behavioural symptoms, which can be challenging for all affected by the disease. A scoping review of studies published between 2011 and 2024 was conducted to present the breadth of behavioural symptoms in ALS and ALSFTD, explore how they are described and assessed, and identify patterns in the literature. FINDINGS: This scoping review identified 3939 articles, with 111/3939 meeting eligibility criteria. Most studies were from Australia (23.22%), Italy (16.94%) and the UK (14.29%); 75.67% were cross-sectional. Sample size ranged from 1 to 1013, as case studies were included. Overall mean age (100/111 studies) was 61.32 (SD = 4.15). Proportion of male patients (reported 102/111 studies) was 61.49%; mean disease duration (reported in 86/111 records) was 32.63 months (SD = 24.72). Papers described a broad range of behavioural symptoms (465 examples), which were thematically collated into seven categories: disinhibition (27.74%), apathy (25.16%), perseverative/compulsive behaviours (17.42%), hyperorality (10.53%), loss of sympathy or empathy (8.6%), psychotic symptoms (7.74%), and loss of insight about disease and changes (2.8%). Most studies (78.37%) used validated behavioural assessments that elicited carer's perspectives. SUMMARY: Despite extensive evidence of behavioural symptoms in ALS, implementation of assessments and management of behavioural symptoms in clinical care remain limited. Clinicians must assess behavioural symptoms, as these can negatively affect disease prognosis, patient treatment engagement and increase family distress. Measures capturing carers' perspectives through interviews are ideal as they can reveal anosognosia, lack of sympathy and lack of empathy.

Binary reversals: a diagnostic sign in primary progressive aphasia.

BACKGROUND: Binary reversals (exemplified by 'yes'/'no' confusions) have been described in patients with primary progressive aphasia (PPA) but their diagnostic value and phenotypic correlates have not been defined. METHODS: We conducted a retrospective cohort study analysing demographic, clinical, neuropsychological, linguistic and behavioural data from patients representing all major PPA syndromes (non-fluent/agrammatic variant, nfvPPA; logopenic variant, lvPPA; semantic variant, svPPA) and behavioural variant frontotemporal dementia (bvFTD). The prevalence of binary reversals and behavioural abnormalities, illness duration, parkinsonian features and neuropsychological test scores were compared between neurodegenerative syndromes, and the diagnostic predictive value of binary reversals was assessed using logistic regression. RESULTS: Data were obtained for 83 patients (21 nfvPPA, 13 lvPPA, 22 svPPA, 27 bvFTD). Binary reversals occurred in all patients with nfvPPA, but significantly less frequently and later in lvPPA (54%), svPPA (9%) and bvFTD (44%). Patients with bvFTD with binary reversals had significantly more severe language (but not general executive or behavioural) deficits than those without reversals. Controlling for potentially confounding variables, binary reversals strongly predicted a diagnosis of nfvPPA over other syndromes. CONCLUSIONS: Binary reversals are a sensitive (though not specific) neurolinguistic feature of nfvPPA, and should suggest this diagnosis if present as a prominent early symptom.

Predictors of primary care psychological therapy outcomes for depression and anxiety in people living with dementia: evidence from national healthcare records in England.

BACKGROUND: Psychological therapies can be effective in reducing symptoms of depression and anxiety in people living with dementia (PLWD). However, factors associated with better therapy outcomes in PLWD are currently unknown. AIMS: To investigate whether dementia-specific and non-dementia-specific factors are associated with therapy outcomes in PLWD. METHOD: National linked healthcare records were used to identify 1522 PLWD who attended psychological therapy services across England. Associations between various factors and therapy outcomes were explored. RESULTS: People with frontotemporal dementia were more likely to experience reliable deterioration in depression/anxiety symptoms compared with people with vascular dementia (odds ratio 2.98, 95% CI 1.08-8.22; P = 0.03) or Alzheimer's disease (odds ratio 2.95, 95% CI 1.15-7.55; P = 0.03). Greater depression severity (reliable recovery: odds ratio 0.95, 95% CI 0.92-0.98, P < 0.001; reliable deterioration: odds ratio 1.73, 95% CI 1.04-2.90, P = 0.04), lower work and social functioning (recovery: odds ratio 0.98, 95% CI 0.96-0.99, P = 0.002), psychotropic medication use (recovery: odds ratio 0.67, 95% CI 0.51-0.90, P = 0.01), being of working age (recovery: odds ratio 2.03, 95% CI 1.10-3.73, P = 0.02) and fewer therapy sessions (recovery: odds ratio 1.12, 95% CI 1.09-1.16, P < 0.001) were associated with worse therapy outcomes in PLWD. CONCLUSIONS: Dementia type was generally not associated with outcomes, whereas clinical factors were consistent with those identified for the general population. Additional support and adaptations may be required to improve therapy outcomes in PLWD, particularly in those who are younger and have more severe depression.

Prevalence of and Factors Associated with Hypersexuality in Patients with Dementia: A Retrospective Cross-Sectional Study.

INTRODUCTION: The psychological and behavioral symptoms of dementia are frequently observed in clinical practice, and those related to sexuality are particularly challenging. However, few studies have evaluated the prevalence or factors associated with hypersexuality in patients with dementia. OBJECTIVES: This study aims to determine the prevalence of hypersexuality in patients with dementia, describe associated factors, and qualitatively report the most common presentations and treatments. METHODS: This retrospective cross-sectional study collected data from semi-structured charts of dementia patients who were followed up at a secondary care reference center between 2015 and 2019. Results: Of 552 total patients, 52 (9.3%) were hypersexual, which was associated with male sex (P < .000; OR 2.95, 95% CI 1.73-5.01), frontotemporal dementia (P < .007), alcohol use (P < .015; OR 2.35, 95% CI 1.16-4.73) and tobacco use (P < .000; OR 2.88, 95% CI 1.61-5.13). CONCLUSIONS: Although our findings were similar to the literature, their significant variability reflects the limited and low quality of the available evidence and a lack of standardization regarding terminology, definitions, and diagnostic criteria for hypersexuality.

Psychiatric Screening Measures in Behavioral Variant Frontotemporal Dementia.

OBJECTIVE: Behavioral variant frontotemporal dementia (bvFTD) is sometimes misdiagnosed as a primary psychiatric disorder, such as major depressive disorder, bipolar disorder, an anxiety disorder, autism spectrum disorder (ASD), or attention-deficit hyperactivity disorder (ADHD). Nonspecialists often use screening measures for primary psychiatric disorders in early assessments of persons with bvFTD. The investigators aimed to evaluate the manifestations of bvFTD in surveys intended to screen for primary psychiatric disorders. METHODS: Patients with bvFTD (N=27) presenting to an academic neurobehavior specialty clinic and their caregivers were provided questionnaire packets including the Mood Disorder Questionnaire (MDQ), the Patient Health Questionnaire-9 (PHQ-9), the Generalized Anxiety Disorder-7 scale (GAD-7), the Adult ADHD Self-Report Scale, version 1.1, the Ritvo Autism and Asperger Diagnostic Scale, and the Neuropsychiatric Inventory Questionnaire. Established cutoff scores suggesting the presence of a primary psychiatric disorder were used to define a "positive" response. Individual questions from each screening questionnaire were examined for a more granular characterization of bvFTD. RESULTS: Overall, 15% of bvFTD patients screened positive for bipolar disorder, 54% screened positive for ADHD, and 89% screened positive for ASD. Hyperactivity or hypersensitivity symptoms were infrequently endorsed. In addition, 57% of respondents screened positive for depressive symptoms on the PHQ-9, and 43% screened positive for anxiety symptoms on the GAD-7. CONCLUSIONS: The use of cutoff scores on screening measures for primary psychiatric disorders resulted in potentially problematic positive screens of primary psychiatric disorders among persons with bvFTD. Identifying specific questions that distinguish between bvFTD and primary psychiatric disorders requires further study.

Social cognition deficits and biometric signatures in the behavioural variant of Alzheimer's disease.

The behavioural variant of Alzheimer's disease (bvAD) is characterized by early predominant behavioural changes, mimicking the behavioural variant of frontotemporal dementia (bvFTD), which is characterized by social cognition deficits and altered biometric responses to socioemotional cues. These functions remain understudied in bvAD. We investigated multiple social cognition components (i.e. emotion recognition, empathy, social norms and moral reasoning), using the Ekman 60 faces test, Interpersonal Reactivity Index, empathy eliciting videos, Social Norms Questionnaire and moral dilemmas, while measuring eye movements and galvanic skin response. We compared 12 patients with bvAD with patients with bvFTD (n = 14), typical Alzheimer's disease (tAD, n = 13) and individuals with subjective cognitive decline (SCD, n = 13), using ANCOVAs and age- and sex-adjusted post hoc testing. Patients with bvAD (40.1 ± 8.6) showed lower scores on the Ekman 60 faces test compared to individuals with SCD (49.7 ± 5.0, P < 0.001), and patients with tAD (46.2 ± 5.3, P = 0.05) and higher scores compared to patients with bvFTD (32.4 ± 7.3, P = 0.002). Eye-tracking during the Ekman 60 faces test revealed no differences in dwell time on the eyes (all P > 0.05), but patients with bvAD (18.7 ± 9.5%) and bvFTD (19.4 ± 14.3%) spent significantly less dwell time on the mouth than individuals with SCD (30.7 ± 11.6%, P < 0.01) and patients with tAD (32.7 ± 12.1%, P < 0.01). Patients with bvAD (11.3 ± 4.6) exhibited lower scores on the Interpersonal Reactivity Index compared with individuals with SCD (15.6 ± 3.1, P = 0.05) and similar scores to patients with bvFTD (8.7 ± 5.6, P = 0.19) and tAD (13.0 ± 3.2, P = 0.43). The galvanic skin response to empathy eliciting videos did not differ between groups (all P > 0.05). Patients with bvAD (16.0 ± 1.6) and bvFTD (15.2 ± 2.2) showed lower scores on the Social Norms Questionnaire than patients with tAD (17.8 ± 2.1, P < 0.05) and individuals with SCD (18.3 ± 1.4, P < 0.05). No group differences were observed in scores on moral dilemmas (all P > 0.05), while only patients with bvFTD (0.9 ± 1.1) showed a lower galvanic skin response during personal dilemmas compared with SCD (3.4 ± 3.3 peaks per min, P = 0.01). Concluding, patients with bvAD showed a similar although milder social cognition profile and a similar eye-tracking signature to patients with bvFTD and greater social cognition impairments and divergent eye movement patterns compared with patients with tAD. Our results suggest reduced attention to salient facial features in these phenotypes, potentially contributing to their emotion recognition deficits.

Cognitive trajectories preluding the onset of different dementia entities: a descriptive longitudinal study using the NACC database.

OBJECTIVE: To describe the 10-year preclinical cognitive trajectories of older, non-demented individuals towards the onset of the four most prevalent types of dementia, i.e., Alzheimer's disease(AD), Lewy body(LBD), vascular(VD) and frontotemporal dementia(FTD). METHODS: Our analysis focused on data from older (≥ 60years) NACC (National Alzheimer's Coordinating Center) participants. Four distinct presymptomatic dementia groups (AD-LBD-VD-FTD) and a comparison group of cognitively unimpaired(CU) participants were formed. Comprehensive cognitive assessments involving verbal episodic memory, semantic verbal fluency, confrontation naming, mental processing speed - attention and executive function - cognitive flexibility were conducted at baseline and on an approximately yearly basis. Descriptive analyses (adjusted general linear models) were performed to determine and compare the yearly cognitive scores of each group throughout the follow-up. Exploratory analyses were conducted to estimate the rates of cognitive decline. RESULTS: There were 3343 participants who developed AD, 247 LBD, 108 FTD, 155 VD and 3398 composed the CU group. Participants with AD performed worse on episodic memory than those with VD and LBD for about 3 to 4 years prior to dementia onset (the FTD group documented an intermediate course). Presymptomatic verbal fluency and confrontation naming trajectories differentiated quite well between the FTD group and the remaining dementia entities. Participants with incident LBD and VD performed worse than those with AD on executive functions and mental processing speed-attention since about 5 years prior to the onset of dementia, and worse than those with FTD more proximally to the diagnosis of the disorder. CONCLUSIONS: Heterogeneous cognitive trajectories characterize the presymptomatic courses of the most prevalent dementia entities.

'Communication is difficult': Speech, language and communication needs of people with young onset or rarer forms of non-language led dementia.

BACKGROUND: People with behavioural variant frontotemporal dementia, Lewy body dementia, posterior cortical atrophy and young onset Alzheimer's disease may experience language and communication difficulties. However, the role of speech and language interventions for people with these non-language led dementias has received little attention. AIMS: This study aimed to explore the experiences and perspectives of people living with these conditions, and their families, regarding their language and communication difficulties and how speech and language therapy could address these needs. METHODS: This study employed a qualitative design to explore the experiences of people living with or caring for somebody with behavioural variant frontotemporal dementia, Lewy body dementia, posterior cortical atrophy or young onset Alzheimer's disease, and to understand their opinions about speech and language therapy. Participants were recruited from a support service connected to a dementia clinic to attend one of five focus group meetings. Videorecorded focus groups and interviews were transcribed, and reflexive thematic analysis was used to analyse data from people affected by each type of dementia. RESULTS: A total of 25 participants were recruited to the study, with representation across the different forms of non-language led dementias. The four main themes identified were: (1) communication difficulties as a key difficulty, (2) loss and loneliness, (3) speech and language therapy, and (4) the role of the caregiver. Sixteen subthemes were also identified which highlighted individual issues across disease types. DISCUSSION: Although all the forms of dementia studied here are not considered to be language-led, people with these conditions and/or their care partners identified speech, language and communication as common challenges. These communication difficulties were reported to have a negative impact on their social participation and mental health and participants felt speech and language interventions could help. There is a need for research exploring speech and language interventions developed for and with people with non-language led dementias and their care partners, to ensure they meet the needs of the people they are designed for. WHAT THIS PAPER ADDS: What is already known on the subject People with primary progressive aphasia present with speech, language and communication difficulties, and several speech and language interventions have been developed to meet the needs of this population. However, people with non-language led dementias may also experience speech, language and communication difficulties, and little is known about interventions that may address these difficulties. What this paper adds to existing knowledge People living with or caring for somebody with behavioural variant frontotemporal dementia, Lewy body dementia, posterior cortical atrophy and young onset Alzheimer's disease report experiencing speech, language and communication difficulties that impact on the person with dementia's social participation and mood. Participants in this study also shared their opinions about how speech and language interventions could help, from the earliest stages of the disease. What are the potential or actual clinical implications of this work? Speech and language therapists need to address the individual speech, language and communication needs of people with dementias, even those that are not thought to be language-led. Current speech and language therapy service provision does not meet the needs of people with non-language led dementias and further research is required to develop interventions and services to meet these needs.

Factors Affecting Performance on a Screening Tool in Persons with Amyotrophic Lateral Sclerosis.

Persons with amyotrophic lateral sclerosis (PALS) are at risk of developing cognitive impairments and frontotemporal dementia (FTD). This study examined the relationship between performance of the ALS-Cognitive Behavioral Screen (ALS-CBS) and the demographic parameters of sex, education, time post-ALS diagnosis, and severity of symptoms. Data were collected retrospectively from 69 participants seen at the Mayo Clinic. Correlations were conducted on the ALS-CBS total scores and subsection scores and the above listed parameters; t-tests were conducted between participant subgroups. No statistically significant relationships or differences occurred between the ALS-CBS or its subsections and the variables measured with exception of age and the attention subsection. Older participants had lower ALS-CBS attention subsection scores. Based on the ALS-CBS scores, most participants had some degree of cognitive impairments: 43 had suspected cognitive impairment, 8 had suspected FTD; 18 fell within the normal range of cognitive function. Overall, the variables of sex, education, time post-diagnosis, and severity of symptoms do not appear to influence ALS-CBS scores. It is recommended cognitive screenings be completed for all PALS due to the high risk for developing cognitive impairments and FTD. Such knowledge can help clinicians develop assessment and treatment plans.

Apraxia Patterns for the Differentiation between Alzheimer's Disease and Frontotemporal Dementia Variants.

Background and Objectives: Despite the increasing use of biomarkers, differentiation between Alzheimer's disease (AD), behavioral variant Frontotemporal Dementia (bvFTD), and Primary Progressive Aphasia (PPA) remains a challenge. Apraxia is a supportive feature for diagnosing AD but is underrepresented in other dementia types. Herein, we investigated the presence and characteristic profiles of limb, verbal, and non-verbal apraxia in three major dementia types. Materials and Methods: Test for Upper Limb Apraxia (TULIA) and Apraxia Battery for Adults-2 (ABA-2) were administered in patients with AD (n = 22), bvFTD (n = 41), and PPA (n = 22), with 20 individuals serving as healthy controls (HC). Composite and subdomain scores were compared between each patient group and the HC. Praxis profiles indicative of each dementia type and a possible predictive value were sought. Results: Apraxia provided high diagnostic accuracy for detecting dementia compared with HC (sensitivity: 63.6-100%, specificity: 79.2-100%). Patients with AD performed worse when imitating intransitive gestures as well as pantomiming transitive gestures (mean differences: 2.10 and 3.12, respectively), compared with bvFTD. PPA patients, compared with bvFTD, had comparable results in limb, verbal, and non-verbal praxis assessments, despite the greater deterioration in the outcome. Compared with patients with AD, PPA had increased pathological outcomes in verbal (86.4% vs. 40.9%) and non-verbal apraxia (31.8% vs. 0%), while bvFTD had increased pathological outcomes in verbal apraxia (85.4% vs. 44.5%). Finally, apraxia is correlated with cognitive decline. Conclusions: Apraxia profile evaluation could contribute to the differentiation between AD and Frontotemporal Dementia (FTD). Both TULIA and ABA-2 are reliable tools that can be performed as bed-side tests in clinical practice.

Social cognition differentiates phenocopy syndrome of behavioural variant frontotemporal dementia from behavioural variant frontotemporal dementia.

BACKGROUND: Patients displaying clinical features of behavioural variant of frontotemporal dementia (bvFTD) but lacking both neuroimaging abnormalities and clinical progression are considered to represent the phenocopy syndrome of bvFTD (phFTD). Extensive clinical overlap between early phase bvFTD and phFTD hampers diagnostic distinction. We aimed to assess the diagnostic value of clinician-rated, self-reported and caregiver-reported symptoms for clinical distinction between phFTD and bvFTD. METHODS: There were 33 phFTD and 95 probable bvFTD patients included in the study (total N = 128). Clinician-rated, self-reported tests and caregiver-reported symptoms were compared between phFTD and bvFTD on social cognition, behaviour, mood and activities of daily living (ADL). Scores were compared between groups, followed by multiple logistic regression analysis, adjusted for age and sex. Receiver operating characteristic curves were plotted to assess diagnostic value. RESULTS: Using clinician-rated and self-reported tests, phFTD patients performed better on facial emotion recognition and reported more depressive symptoms. Caregiver-reported behavioural symptoms indicated higher behavioural and ADL impairment in phFTD compared to bvFTD. Facial emotion recognition provided highest diagnostic accuracy for distinction of phFTD from bvFTD (area under the curve (AUC) 0.813 95% CI 0.735-0.892, P < 0.001, sensitivity 81%, specificity 74%) followed by depressive symptoms (AUC 0.769 95% 0.674-0.864, P < 0.001 sensitivity 81%, specificity of 63%). CONCLUSION: Social cognition tests are most suitable for distinction of phFTD from bvFTD. Caregiver-reported questionnaires and phFTD diagnosis seemed inversely correlated, showing more symptoms in phFTD. Further research is needed on phFTD aetiology and in caregivers taking into account disease burden to assess what explains this discrepancy between clinician-rated and caregiver-based tools.

Altered reward processing underpins emotional apathy in dementia.

INTRODUCTION: While apathy is broadly defined as a loss of motivation, it is increasingly recognised as a multidimensional syndrome spanning executive, emotional, and initiation domains. Emotional apathy is purportedly driven by deficits in using socioemotional rewards to guide behaviour, yet the link between these symptoms and reward processing, and their common neural correlates, has not been directly examined. METHODS: Sixty-four patients (33 behavioural-variant frontotemporal dementia, 14 Alzheimer's disease, 8 semantic dementia, 6 progressive nonfluent aphasia, 3 logopenic progressive aphasia) were classified into high (HEA; n = 36) and low (LEA; n = 28) emotional apathy groups based on emotional apathy subscale scores on the Dimensional Apathy Scale. Patients and age-matched healthy controls (n = 27) performed an instrumental reward learning task where they learned to associate cues with either social or monetary outcomes. RESULTS: HEA patients showed impaired learning on both the social and monetary reward conditions, relative to LEA patients (p = 0.016) and controls (p = 0.005). Conversely, the LEA group did not differ from controls (p = 0.925). Importantly, multiple regression analyses indicated that social reward learning significantly predicted emotional apathy. Voxel-based morphometry analyses revealed that emotional apathy and social reward learning were both associated with orbitofrontal cortex, ventral striatum, and insula atrophy. DISCUSSION: Our results demonstrate a unique link between impaired social reward learning and emotional apathy in dementia and reveal a shared neurobiological basis. Greater understanding of these neurocognitive mechanisms of reward processing will help improve the identification of emotional apathy in dementia and inform the development of novel interventions to address these symptoms.

Current Potential for Clinical Optimization of Social Cognition Assessment for Frontotemporal Dementia and Primary Psychiatric Disorders.

Dodich and colleagues recently reviewed the evidence supporting clinical use of social cognition assessment in behavioral variant frontotemporal dementia (Dodich et al., 2021). Here, we comment on their methods and present an initiative to address some of the limitations that emerged from their study. In particular, we established the social cognition workgroup within the Neuropsychiatric International Consortium Frontotemporal dementia (scNIC-FTD), aiming to validate social cognition assessment for diagnostic purposes and tracking of change across clinical situations.

Diagnostic Instability Over Time in the Late-Onset Frontal Lobe Syndrome: When Can We Say it's FTD?

OBJECTIVES: Distinguishing sporadic behavioral variant of frontotemporal dementia (bvFTD) from late-onset primary psychiatric disorders (PPD) remains challenging with the lack of robust biomarkers. An early bvFTD misdiagnosis in PPD cases and vice-versa is common. Little is known about diagnostic (in)stability over longer period of time. We investigated diagnostic instability in a neuropsychiatric cohort up to 8 years after baseline visit and identified which clinical hallmarks contribute to diagnostic instability. DESIGN: Diagnoses of participants of the late-onset frontal lobe (LOF) study were collected from the baseline visit (T0) and the 2-year follow-up visit (T2). Clinical outcomes were retrieved 5-8 years after baseline visit (Tfinal). Endpoint diagnoses were categorized into bvFTD, PPD and other neurological disorders (OND). We calculated the total amount of participants that switched diagnosis between T0-T2 and T2-Tfinal. Clinical records of participants that switched diagnosis were assessed. RESULTS: Of the 137 patients that were included in the study, the final diagnoses at Tfinal were bvFTD 24.1% (n = 33), PPD 39.4% (n = 54), OND 33.6% (n = 46) and unknown 2.9% (n = 4). Between T0 and T2, a total of 29 (21.2%) patients switched diagnosis. Between T2 and Tfinal, 8 (5.8%) patients switched diagnosis. Prolonged follow-up identified few cases with diagnostic instability. Major contributors to diagnostic instability where a nonconverting diagnosis of possible bvFTD and a probable bvFTD diagnosis based on informant-based history and an abnormal FDG-PET scan whilst having a normal MRI. CONCLUSION: Considering these lessons, a FTD diagnosis remains stable enough to conclude that 2 years is sufficient to say if a patient with late-life behavioral disorder has FTD.

Decreased emotion recognition and reduced focus on facial hallmarks in behavioral variant frontotemporal dementia compared to primary psychiatric disorders and controls.

BACKGROUND AND PURPOSE: Early diagnosis of behavioral variant frontotemporal dementia (bvFTD) is challenging due to symptomatic overlap with primary psychiatric disorders (PPD). As emotion recognition deficits are early and key features of bvFTD, the aim was to explore processes driving social cognition deficits that may aid in the differentiation between bvFTD and PPD. METHODS: The total sample (N = 51) included 18 patients with bvFTD, 11 patients with PPD (mood, autism spectrum and psychotic disorders) and 22 controls from the Alzheimer Center Amsterdam of the Amsterdam UMC. Emotion recognition was assessed with the Ekman 60 Faces test, during which eye tracking metrics were collected in the first 5 s a face was presented. Group differences in dwell time on the total image as well as the circumscribed eyes area and mouth area were analysed using ANOVA, with post hoc comparisons. RESULTS: Patients with bvFTD scored lowest, patients with PPD scored intermediate and controls scored highest on emotion recognition. During facial processing, patients with bvFTD spent less dwell time on the total image than controls (mean difference 11.3%, F(2, 48) = 6.095, p = 0.004; bvFTD-controls p = 0.001, 95% confidence interval [CI] -892.64, -239.70). Dwell time on the eyes area did not differ between diagnostic groups, whilst patients with bvFTD spent less dwell time on the mouth area than PPD patients (mean difference 10.7%; F(2, 48) = 3.423, p = 0.041; bvFTD-PPD p = 0.022, 95% CI -986.38, -79.47) and controls (mean difference 7.8%; bvFTD-controls p = 0.043, 95% CI -765.91, -12.76). CONCLUSIONS: In bvFTD, decreased emotion recognition may be related to reduced focus on facial hallmarks. These findings suggest a valuable role for biometrics in social cognition assessment and the differentiation between bvFTD and PPD.

Exploring Social Cognition Tests to Differentiate Frontotemporal Dementia from Depression: A Two-Step Pilot Study.

Behavioral-variant frontotemporal dementia (bvFTD) is challenging to recognize, and often misdiagnosed as depression (DEP). Evidence suggests changes in social cognition (SoCog) precede general cognitive decline in bvFTD. Currently, there are no screening measures of social cognition. 17 bvFTD, 16 DEP, and 18 control participants underwent 6 SoCog tests measuring: emotion recognition; theory of mind; empathy; insight. We used χ 2 , Wilcoxon rank sum, Kruskal-Wallis tests to compare groups, with decision tree analysis to identify items that best differentiated bvFTD from DEP. bvFTD performed significantly worse on all SoCog tasks compared with other groups. Decision tree analysis yielded a 5-item test with ROC area under the curve of 0.973 (95% CI: 0.928, 1.0) for differentiating bvFTD versus depression. These results suggest that it may be feasible to develop a screening measure of social cognition.

Living With Frontotemporal Degeneration: Diagnostic Journey, Symptom Experiences, and Disease Impact.

Frontotemporal degeneration (FTD) is an umbrella term encompassing a range of rare neurodegenerative disorders that cause progressive declines in cognition, behavior, and personality. Hearing directly from individuals living with FTD and their care partners is critical in optimizing care, identifying meaningful clinical trial endpoints, and improving research recruitment and retention. The current paper presents a subset of data from the FTD Insights Survey, chronicling the diagnostic journey, symptoms, and the impact of FTD on distress, quality of life, and independence, in the mild to moderate stages of the disease. Survey respondents included 219 individuals diagnosed with FTD and 437 current care partners, representing a range of FTD diagnoses. Around half of survey respondents reported seeing three or more doctors before an FTD diagnosis was given, and a range of prior diagnoses were noted. Most frequently endorsed symptoms tended to be consistent with clinical characteristics of the specific diagnosis, though there was significant variability in symptoms reported within diagnostic categories as well as considerable overlap in symptoms between diagnostic categories. Cognitive and language symptoms of FTD were generally most distressing to the person diagnosed, and a loss of independence was endorsed as affecting quality of life. The distinct perspectives of diagnosed persons and care partners regarding disease impact differed notably for bvFTD/Pick's disease. Participating independently in a range of activities, within the home, outside the home, and with other people, were reported as challenging for people living with FTD, underscoring the degree to which the lives of these individuals are affected even at the mild and moderate stages of disease. Overall, by heeding the perspectives of those living with FTD, we can begin to design more meaningful research studies, provide better care, and develop therapies that improve quality of life.

Demographic and Symptom Correlates of Initial Idiopathic Psychiatric Diagnosis in Frontotemporal Dementia.

INTRODUCTION: This study aims to measure frequency and correlates of initial idiopathic psychiatric diagnosis in a cohort of 147 patients with Frontotemporal Dementia (FTD)-spectrum disorders. METHODS: Participants were evaluated at the National Institutes of Health in Bethesda, Maryland. Initial participant diagnoses were determined by chart review and patient and informant interviews. Logistic regression was used to assess the relationships between diagnosis and age of symptom onset, gender, education, family history of psychiatric illness, and family history of dementia. Additional exploratory analyses investigated patients' first symptom type. RESULTS: 25% (n=43) of all the patients reviewed were initially misdiagnosed with an idiopathic psychiatric illness, which is less than half the commonly cited 50% rate.3 Depression was the most common misdiagnosis (46.5%). Family history of dementia, family history of mental illness and an exploratory analysis of behavioral first symptoms suggested significant association with a greater likelihood of initial idiopathic psychiatric diagnosis in FTD patients. DISCUSSION: This data confirms patterns of initial idiopathic psychiatric diagnosis in FTD and elucidates potential factors underlying misdiagnosis. Potential implications for patient outcomes, caregiver burden and healthcare costs are discussed.