The Frontal Behavioural Inventory (Italian version) differentiates frontotemporal lobar degeneration variants from Alzheimer's disease

Clinical and imaging correlates of hyperorality in syndromes associated with frontotemporal lobar degeneration

AIM

Empirical research investigating hyperorality in syndromes associated with frontotemporal lobar degeneration (FTLD) is limited. The present study aims to assess and describe hyperorality and its clinical and imaging correlates in patients with FTLD-associated syndromes.

METHODS

This retrospective longitudinal study included consecutive patients with FTLD who underwent a clinical, cognitive, and behavioral assessment. The presence and severity of hyperorality was assessed using the Frontal Behavior Inventory.

RESULTS

A total of 712 patients with FTLD were included in the study. Hyperorality was reported by 29% (204 of 712 [95% CI: 25-32%]) of patients; was more frequent in those with severe dementia than in those with prodromal or mild to moderate dementia (P < 0.05); was associated with younger age (odds ratio [OR] = 0.96 [95% CI: 0.94-0.99]), (P = 0.003) and positive family history for dementia (OR = 2.03 [95% CI: 1.18-3.49], P = 0.010); was overall more probable in the behavioral variant of frontotemporal dementia (bvFTD) and frontotemporal dementia with amyotrophic lateral sclerosis phenotypes, and less probable in other language or motor phenotypes; and was associated with higher severity of neuropsychiatric symptoms (OR = 1.08 [95% CI: 1.06-1.10], P < 0.001) and with the presence of several behavioral symptoms (P < 0.05). Moreover, hyperorality severity increased over time only in patients with bvFTD (β = +0.15, P = 0.011) or semantic variant of primary progressive aphasia (β = +0.34, P = 0.010). Finally, the presence of hyperorality was significantly associated with greater atrophy in the right anterior insula and right orbitofrontal region (false discovery rate-corrected P < 0.05).

CONCLUSION

Hyperorality is common in certain FTLD-associated syndromes. Understanding its correlates can help clinicians define pharmacological and educational interventions and clarify related anatomical circuits.

Association of APOE genotype and cerebrospinal fluid Aβ and tau biomarkers with cognitive and motor phenotype in amyotrophic lateral sclerosis

OBJECTIVE

Little is known about amyotrophic lateral sclerosis (ALS)-nonspecific cognitive deficits - most notably memory disturbance - and their biological underpinnings. We investigated the associations of the Alzheimer's disease (AD) genetic risk factor APOE and cerebrospinal fluid (CSF) biomarkers Aβ and tau proteins with cognitive and motor phenotype in ALS.

METHODS

APOE haplotype was determined in 281 ALS patients; for 105 of these, CSF levels of Aβ42, Aβ40, total tau (T-tau), and phosphorylated tau (P-tau181) were quantified by chemiluminescence enzyme immunoassay (CLEIA). The Edinburgh Cognitive and Behavioural ALS Screen (ECAS) was employed to evaluate the neuropsychological phenotype.

RESULTS

APOE-E4 allele was associated with worse ECAS memory score (median, 14.0 in carriers vs. 16.0 in non-carriers) and lower CSF Aβ42 (-0.8 vs. 0.1, log-transformed values) and Aβ42/40 ratio (-0.1 vs. 0.3). Some 37.1% of ALS patients showed low Aβ42 levels, possibly reflecting cerebral Aβ deposition. While lower Aβ42/40 correlated with lower memory score (β = 0.20), Aβ42 positively correlated with both ALS-specific (β = 0.24) and ALS-nonspecific (β = 0.24) scores. Although Aβ42/40 negatively correlated with T-tau (β = -0.29) and P-tau181 (β = -0.33), we found an unexpected positive association of Aβ42 and Aβ40 with both tau proteins. Regarding motor phenotype, lower levels of Aβ species were associated with lower motor neuron (LMN) signs (Aβ40: β = 0.34; Aβ42: β = 0.22).

CONCLUSIONS

APOE haplotype and CSF Aβ biomarkers are associated with cognitive deficits in ALS and particularly with memory impairment. This might partly reflect AD-like pathophysiological processes, but additional ALS-specific mechanisms could be involved.

Neuropsychiatric Symptoms in Frontotemporal Dementia: More Than Just Noise?

Background

Neuropsychiatric symptoms cause significant suffering and poor quality of life for patients and their caregivers. They are not considered specific to frontotemporal dementia (FTD); therefore, their clinical role and impact might be underestimated.

Objective

The aims of the present study are to: 1) describe the prevalence of neuropsychiatric symptoms in FTD starting from the prodromal stage, 2) define their association with disease severity, 3) identify symptoms which are unrelated to FTD-specific symptoms, and 4) assess their association with clinical features and outcomes.

Results

In this retrospective study, we analyzed data of 461 FTD patients, including behavioral variant of FTD (bvFTD, n = 318) and primary progressive aphasia (PPA, n = 143). Neuropsychiatric symptoms were assessed using the Neuropsychiatric Inventory, and patients' staging and global disease severity were estimated using the Clinical Dementia Rating plus NACC FTLD.

Results

The most common neuropsychiatric symptoms in prodromal FTD were irritability (48%), depression (35%), and anxiety (34%); delusions were reported in 6%of prodromal bvFTD cases. The severity of most neuropsychiatric symptoms increased with global disease severity. Psychosis (delusions and hallucinations) and mood symptoms (depression and anxiety) were mostly independent from FTD-specific symptoms. Psychosis was associated with older age, higher disease severity, shorter survival rate, and was higher in bvFTD than in PPA.

Conclusions

Neuropsychiatric symptoms are common in patients with FTD, also in the prodromal phase. Psychosis might be unrelated to FTD pathology, and be associated with worse clinical outcomes. The prompt detection and treatment of these symptoms might improve patient's management and quality of life.

Regional spreading pattern is associated with clinical phenotype in amyotrophic lateral sclerosis

Increasing evidence shows that disease spreading in amyotrophic lateral sclerosis (ALS) follows a preferential pattern with more frequent involvement of contiguous regions from the site of symptom onset. The aim of our study was to assess if: (i) the burden of upper (UMN) and lower motor neuron (LMN) involvement influences directionality of disease spreading; (ii) specific patterns of disease progression are associated with motor and neuropsychological features of different ALS subtypes (classic, bulbar, primary lateral sclerosis, UMN-predominant, progressive muscular atrophy, flail arm, flail leg); and (iii) specific clinical features may help identify ALS subtypes, which remain localized to the site of onset for a prolonged time (regionally entrenching ALS). A single-centre, retrospective cohort of 913 Italian ALS patients was evaluated to assess correlations between directionality of the disease process after symptom onset and motor/neuropsychological phenotype. All patients underwent an extensive evaluation including the following clinical scales: Penn Upper Motor Neuron Score (PUMNS), MRC Scale for Muscle Strength and the Edinburgh Cognitive and Behavioural ALS Screen (ECAS). The most frequent initial spreading pattern was that towards adjacent horizontal regions (77.3%), which occurred preferentially in patients with lower MRC scores (P = 0.038), while vertical diffusion (21.1%) was associated with higher PUMNS (P < 0.001) and with reduced survival (P < 0.001). Non-contiguous disease spreading was associated with more severe UMN impairment (P = 0.003), while contiguous disease pattern with lower MRC scores. Furthermore, non-contiguous disease spreading was associated with more severe cognitive impairment in both executive and visuospatial ECAS domains. Individuals with regionally entrenching ALS were more frequently female (45.6% versus 36.9%; P = 0.028) and had higher frequencies of symmetric disease onset (40.3% versus 19.7%; P < 0.001) and bulbar phenotype (38.5% versus 16.4%; P < 0.001). Our study suggests that motor phenotypes characterized by a predominant UMN involvement are associated with a vertical pattern of disease progression reflecting ipsilateral spreading within the motor cortex, while those with predominant LMN involvement display more frequently a horizontal spreading from one side of the spinal cord to the other. These observations raise the hypothesis that one of the mechanisms underlying disease spreading in ALS pathology is represented by diffusion of toxic factors in the neuron microenvironment. Finally, it is possible that in our cohort, regionally entrenching ALS forms are mainly observed in patients with atypical bulbar phenotypes, characterized by a slowly progressive course and relatively benign prognosis.

Association of Choroid Plexus Volume With Serum Biomarkers, Clinical Features, and Disease Severity in Patients With Frontotemporal Lobar Degeneration Spectrum

BACKGROUND AND OBJECTIVES

Choroid plexus (ChP) is emerging as a key brain structure in the pathophysiology of neurodegenerative disorders. In this observational study, we investigated ChP volume in a large cohort of patients with frontotemporal lobar degeneration (FTLD) spectrum to explore a possible link between ChP volume and other disease-specific biomarkers.

METHODS

Participants included patients meeting clinical criteria for a probable syndrome in the FTLD spectrum. Structural brain MRI imaging, serum neurofilament light (NfL), serum phosphorylated-Tau181 (p-Tau181), and cognitive and behavioral data were collected. MRI ChP volumes were obtained from an ad-hoc segmentation model based on a Gaussian Mixture Models algorithm.

RESULTS

Three-hundred and sixteen patients within FTLD spectrum were included in this study, specifically 135 patients diagnosed with behavioral variant frontotemporal dementia (bvFTD), 75 primary progressive aphasia, 46 progressive supranuclear palsy, and 60 corticobasal syndrome. In addition, 82 age-matched healthy participants were recruited as controls (HCs). ChP volume was significantly larger in patients with FTLD compared with HC, across the clinical subtype. Moreover, we found a significant difference in ChP volume between HC and patients stratified for disease-severity based on CDR plus NACC FTLD, including patients at very early stage of the disease. Interestingly, ChP volume correlated with serum NfL, cognitive/behavioral deficits, and with patterns of cortical atrophy. Finally, ChP volume seemed to discriminate HC from patients with FTLD better than other previously identified brain structure volumes.

DISCUSSION

Considering the clinical, pathologic, and genetic heterogeneity of the disease, ChP could represent a potential biomarker across the FTLD spectrum, especially at the early stage of disease. Further longitudinal studies are needed to establish its role in disease onset and progression.

CLASSIFICATION OF EVIDENCE

This study provides Class III evidence that choroid plexus volume, as measured on MRI scan, can assist in differentiating patients with FTLD from healthy controls and in characterizing disease severity.

Phenotypic correlates of serum neurofilament light chain levels in amyotrophic lateral sclerosis

Objective

To investigate the relationship between serum levels of the neuroaxonal degeneration biomarker neurofilament light chain (NFL) and phenotype in ALS.

Materials and methods

Serum NFL (sNFL) concentration was quantified in 209 ALS patients and 46 neurologically healthy controls (NHCs).

Results

sNFL was clearly increased in ALS patients and discriminated them from NHCs with AUC = 0.9694. Among ALS patients, females had higher sNFL levels, especially in case of bulbar onset. sNFL was more increased in phenotypes with both upper (UMN) and lower motor neuron (LMN) signs, and particularly in those with UMN predominance, compared to LMN forms. At the same time, primary lateral sclerosis (PLS) had significantly lower levels compared to UMN-predominant ALS (AUC = 0.7667). sNFL correlated negatively with disease duration at sampling and ALSFRS-R score, positively with disease progression rate, differed among King’s stages, and was negatively associated with survival. It also correlated with clinical/neurophysiological indices of UMN and LMN dysfunction (Penn UMN Score, LMN score, MRC composite score, active spinal denervation score). On the contrary, sNFL was not associated with cognitive deficits nor with respiratory parameters. Notably, we found a negative correlation between sNFL and estimated glomerular filtration rate (eGFR).

Interpretation

We confirm that ALS is characterized by increased sNFL levels, whose main determinant is the rate of degeneration of both UMNs and LMNs. sNFL is a biomarker of only motor, not of extra-motor, disease. The negative correlation with kidney function might reflect varying renal clearance of the molecule and deserves further investigation before introducing sNFL measurement as routine test in clinical care of ALS patients.

Diagnostic properties of the Italian ECAS Carer Interview (ECAS-CI)

BACKGROUND

This study aimed at providing diagnostic properties and normative cut-offs for the Italian ECAS Carer Interview (ECAS-CI).

MATERIALS

N = 292 non-demented ALS patients and N = 107 healthy controls (HCs) underwent the ECAS-CI and the Frontal Behavioural Inventory (FBI). Two ECAS-CI measures were addressed: (1) the number of symptoms (NoS; range = 0-13) and (2) that of individual symptom clusters (SC; range = 0-6). Diagnostics were explored against an FBI score ≥ than the 95th percentile of the patients' distribution.

RESULTS

Both the NoS and SC discriminated patient from HCs. High accuracy, sensitivity, and specificity were detected for both the NoS and SC; however, at variance with SC, the NoS showed better post-test features and did not overestimate the occurrence of behavioural changes. The ECAS-CI converged with the FBI and diverged from the cognitive section of the ECAS.

DISCUSSION

The ECAS-CI is a suitable screener for behavioural changes in ALS patients, with the NoS being its best outcome measure (cut-off: ≥ 3).

Association of the risk factor UNC13A with survival and upper motor neuron involvement in amyotrophic lateral sclerosis

Background

The UNC13A gene is an established susceptibility locus for amyotrophic lateral sclerosis (ALS) and a determinant of shorter survival after disease onset, with up to 33.0 months difference in life expectancy for carriers of the rs12608932 risk genotype. However, its overall effect on other clinical features and ALS phenotypic variability is controversial.

Methods

Genotype data of the UNC13A rs12608932 SNP (A-major allele; C-minor allele) was obtained from a cohort of 972 ALS patients. Demographic and clinical variables were collected, including cognitive and behavioral profiles, evaluated through the Edinburgh Cognitive and Behavioral ALS Screen (ECAS) - Italian version and the Frontal Behavioral Inventory (FBI); upper and lower motor neuron involvement, assessed by the Penn Upper Motor Neuron Score (PUMNS) and the Lower Motor Neuron Score (LMNS)/Medical Research Council (MRC) scores, respectively; the ALS Functional Rating Scale Revised (ALSFRS-R) score at evaluation and progression rate; age and site of onset; survival. The comparison between the three rs12608932 genotypes (AA, AC, and CC) was performed using the additive, dominant, and recessive genetic models.

Results

The rs12608932 minor allele frequency was 0.31 in our ALS cohort, in comparison to 0.33-0.41 reported in other Caucasian ALS populations. Carriers of at least one minor C allele (AC + CC genotypes) had a shorter median survival than patients with the wild-type AA genotype (-11.7 months, p = 0.013), even after adjusting for age and site of onset, C9orf72 mutational status and gender. Patients harboring at least one major A allele (AA + AC genotypes) and particularly those with the wild-type AA genotype showed a significantly higher PUMNS compared to CC carriers (p = 0.015 and p_adj = 0.037, respectively), thus indicating a more severe upper motor neuron involvement. Our analysis did not detect significant associations with all the other clinical parameters considered.

Conclusion

Overall, our findings confirm the role of UNC13A as a determinant of survival in ALS patients and show the association of this locus also with upper motor neuron involvement.

Standardization of the Italian ALS-CBS™ Caregiver Behavioral Questionnaire

Background

The present investigation aimed at testing the psychometrics and diagnostics of the Italian version of the Caregiver Behavioral Questionnaire (CBQ) from the ALS Cognitive Behavioral Screen (ALS-CBS™), as well as its case-control discrimination, in a cohort of non-demented patients with ALS.

Methods

The caregivers of N = 265 non-demented patients with ALS and N = 99 healthy controls (HCs) were administered the CBQ and the Edinburgh Cognitive and Behavioural ALS Screen-Carer Interview (ECAS-CI). For N = 98 patients, an in-depth behavioural/psychopathological assessment via the Frontal Behavioural Inventory (FBI), the Dimensional Apathy Scale (DAS), the State and Trait Anxiety Inventory-Form Y (STAI-Y), and the Beck Depression Inventory (BDI) was also available. Factorial and construct validity, internal reliability, and diagnostics against an abnormal ECAS-CI score were tested in patients. Case-control discrimination was explored through logistic regression.

Results

The CBQ was internally reliable (McDonald's ω = 0.90) and underpinned by a simple, unidimensional structure; it converged with ECAS-CI, FBI, and DAS scores and diverged from STAI-Y and BDI ones. A cutoff of ≤ 33 accurately detected abnormal ECAS-CI scores (AUC = 0.85), yielding optimal error- and information-based diagnostics. The CBQ was independent of demographic and disease-related variables and discriminated patients from HCs (p < 0.001).

Discussion

The Italian version of the CBQ from the ALS-CBS™ is a valid, reliable, diagnostically sound, and feasible screener for detecting frontotemporal-like behavioural changes in non-demented patients with ALS. Its adoption is thus recommended within clinical practice and research in the view of providing preliminary information on whether the administration of more extensive behavioural instruments is needed.

The Cerebellum Is a Key Structure in the Neural Network for Mentalizing: An MRI Study in the Behavioral Variant of Frontotemporal Dementia

The behavioural variant of frontotemporal dementia (bvFTD) is primarily characterized by deficits in social behaviour and theory of mind (ToM). Although a consensus has been reached on the roles of the cerebellum in social cognition and ToM, its specific contribution to social impairments of bvFTD has never been specifically investigated. The aim of this study was to assess cerebellar structural and functional changes in patients with bvFTD and their potential association with ToM deficits of patients. Therefore, 15 patients with bvFTD and 34 healthy subjects underwent an MRI examination. Voxel-based morphometry was used to assess cerebellar (GM) changes, and a seed-based analysis was performed to test cerebello-cerebral functional connectivity (FC). The performance of bvFTD patients in a ToM task was then correlated with FC patterns. Compared to healthy subjects, patients with bvFTD showed significant cerebellar GM loss specifically involving cerebellar Crus I-II. Additionally, FC changes FC were observed between the cerebellum and cerebral regions related to ToM. Interestingly, patterns of changes in cerebello-cerebral FC correlated with altered ToM performances explored using the "Reading the Mind with the Eyes" test (RMET) of patients. The present findings suggest that specific changes in cerebello-cerebral FC may underlie ToM alterations in patients with bvFTD.

Validity and diagnostics of the Reading the Mind in the Eyes Test (RMET) in non-demented amyotrophic lateral sclerosis (ALS) patients

Background

The aim of this study was to explore the construct validity and diagnostic properties of the Reading the Mind in the Eyes Test (RMET) in non-demented patients with amyotrophic lateral sclerosis (ALS).

Materials

A total of 61 consecutive patients and 50 healthy controls (HCs) were administered the 36-item RMET. Additionally, patients underwent a comprehensive assessment of social cognition via the Story-Based Empathy Task (SET), which encompasses three subtests targeting Causal Inference, Emotion Attribution (SET-EA), and Intention Attribution (SET-IA), as well as global cognitive [the Edinburgh Cognitive and Behavioral ALS Screen (ECAS)] and behavioral screening [the Frontal Behavioral Inventory (FBI); the Dimensional Apathy Scale (DAS); the Beck Depression Inventory (BDI); and the State and Trait Anxiety Inventory-Y]. The construct validity of the RMET was tested by regressing it within a stepwise model that encompassed as predictors the abovementioned cognitive and behavioral measures, covarying for demographic and motor confounders. Receiver-operating characteristics (ROC) analyses allowed exploring intrinsic and post-test properties of the RMET both in discriminating patients from HCs and in identifying patients with a defective SET-EA performance.

Results

The RMET was solely predicted by the SET-EA (p = 0.003) and SET-IA (p = 0.005). RMET scores showed high accuracy both in discriminating patients from HCs (AUC = 0.81) and in identifying patients with a defective SET-EA score (AUC = 0.82), with adequate-to-optimal both intrinsic and post-test properties.

Discussion

The RMET is a convergently and divergently valid measure of affective social cognition in non-demented ALS patients, also featuring optimal intrinsic and post-test diagnostic properties in both case-control and case-finding scenarios.

Behavioral and Cognitive Phenotypes of Patients With Amyotrophic Lateral Sclerosis Carrying SOD1 Variants

BACKGROUND AND OBJECTIVES

SOD1 variants in patients with amyotrophic lateral sclerosis (ALS) have been associated with peculiar clinical features and disease progression but rarely with cognitive and behavioral impairment. This study aims at describing the features of frontotemporal syndromes in patients with ALS carrying SOD1 variants.

METHODS

Italian patients with ALS were consecutively enrolled between 2012 and 2020 at our Motor Neuron Disease Center. All underwent clinical assessment, extensive neurophysiologic test battery for the evaluation of cognitive functions and behavior, and targeted next-generation sequencing of SOD1, FUS, TARDBP, VCP, PFN1, TUBA4A, OPTN, SQSTM1, UBQLN2, and C9orf72 genes. Neuropsychological profiles of SOD1+ patients (SOD1+) were compared with those with no gene variants (SOD1-). To this aim, the occurrence of cognitive and behavioral impairment defined according to the current guidelines, the number of pathologic test performances based on Italian normative values, and scores of the Frontal Behavioral Inventory were collected.

RESULTS

Among 288 patients consecutively examined, we identified 8 known pathogenic SOD1 variants and one variant of uncertain significance (p.Ser26Asn) not previously described in 14 patients with ALS belonging to 11 families. The clinical phenotypes were mainly characterized by predominant lower motor neuron involvement with onset at the lower limbs, and one patient had bulbar onset. SOD1+ patients (n = 14) were compared with SOD1- patients (N = 274). SOD1+ patients were younger than SOD1-, and both groups had similar functional motor disabilities and disease duration. Based on the overall neuropsychological findings, the percentage of SOD1+ and SOD1- patients with altered profiles were approximately 60%. However, behavioral impairment defined by the Strong criteria, and most commonly featuring with irritability and mental rigidity, was more frequent in SOD1+ than SOD1- patients and mainly associated with variants in exon 5. Conversely, cognitive impairment was mainly found in SOD1- patients.

DISCUSSION

Our findings from a large cohort of deeply phenotyped patients with ALS demonstrated that behavioral involvement is more common than previously thought among patients harboring SOD1 variants and that it is independent from patients' age and disease stage. These findings could be relevant for the assessment of clinical trial outcomes and disease management.

Neuroanatomical correlates of screening for aphasia in NeuroDegeneration (SAND) battery in non-fluent/agrammatic variant of primary progressive aphasia

Background

Non-fluent/agrammatic variant of Primary Progressive Aphasia (avPPA) is primarily characterized by language impairment due to atrophy of the inferior frontal gyrus and the insula cortex in the dominant hemisphere. The Screening for Aphasia in NeuroDegeneration (SAND) battery has been recently proposed as a screening tool for PPA, with several tasks designed to be specific for different language features. Applying multivariate approaches to neuroimaging data and verbal fluency tasks, Aachener Aphasie Test (AAT) naming subtest and SAND data may help in elucidating the neuroanatomical correlates of language deficits in avPPA.

Objective

To investigate the neuroanatomical correlates of language deficits in avPPA using verbal fluency tasks, AAT naming subtest and SAND scores as proxies of brain structural imaging abnormalities.

Methods

Thirty-one avPPA patients were consecutively enrolled and underwent extensive neuropsychological assessment and MRI scan. Raw scores of verbal fluency tasks, AAT naming subtest, and SAND subtests, namely living and non-living picture naming, auditory sentence comprehension, single-word comprehension, words and non-words repetition and sentence repetition, were used as proxies to explore structural (gray matter volume) neuroanatomical correlates. We assessed univariate (voxel-based morphometry, VBM) as well as multivariate (source-based morphometry, SBM) approaches. Age, gender, educational level, and disease severity were considered nuisance variables.

Results

SAND picture naming (total, living and non-living scores) and AAT naming scores showed a direct correlation with the left temporal network derived from SBM. At univariate analysis, the left middle temporal gyrus was directly correlated with SAND picture naming (total and non-living scores) and AAT naming score. When words and non-words repetition (total score) was considered, a direct correlation with the left temporal network (SBM) and with the left fusiform gyrus (VBM) was also evident.

Conclusion

Naming impairments that characterize avPPA are related to specific network-based involvement of the left temporal network, potentially expanding our knowledge on the neuroanatomical basis of this neurodegenerative condition.

Sex influences clinical phenotype in frontotemporal dementia

INTRODUCTION

Frontotemporal dementia (FTD) encompasses a wide spectrum of genetic, clinical, and histological findings. Sex is emerging as a potential biological variable influencing FTD heterogeneity; however, only a few studies explored this issue with nonconclusive results.

OBJECTIVE

To estimate the role of sex in a single-center large cohort of FTD patients.

METHODS

Five hundred thirty-one FTD patients were consecutively enrolled. Demographic, clinical, and neuropsychological features, survival rate, and serum neurofilament light (NfL) concentration were determined and compared between sex.

RESULTS

The behavioral variant of FTD was more common in men, whereas primary progressive aphasia was overrepresented in women (p < 0.001). While global cognitive impairment was comparable, females had a more severe cognitive impairment, namely in Trail Making Test parts A and B (p = 0.003), semantic fluency (p = 0.03), Short Story Recall Test (p = 0.003), and the copy of Rey Complex Figure (p = 0.005). On the other hand, men exhibited more personality/behavioral symptoms (Frontal Behavior Inventory [FBI] AB, p = 0.003), displaying higher scores in positive FBI subscales (FBI B, p < 0.001). In particular, apathy (p = 0.02), irritability (p = 0.006), poor judgment (p = 0.033), aggressivity (p = 0.008), and hypersexuality (p = 0.006) were more common in men, after correction for disease severity. NfL concentration and survival were not statistically different between men and women (p = 0.167 and p = 0.645, respectively).

DISCUSSION

The present study demonstrated that sex is a potential factor in determining FTD phenotype, while it does not influence survival. Although the pathophysiological contribution of sex in neurodegeneration is not well characterized yet, our findings highlight its role as deserving biological variable in FTD.

TMEM106B Acts as a Modifier of Cognitive and Motor Functions in Amyotrophic Lateral Sclerosis

The transmembrane protein 106B (TMEM106B) gene is a susceptibility factor and disease modifier of frontotemporal dementia, but few studies have investigated its role in amyotrophic lateral sclerosis. The aim of this work was to assess the impact of the TMEM106B rs1990622 (A–major risk allele; G–minor allele) on phenotypic variability of 865 patients with amyotrophic lateral sclerosis. Demographic and clinical features were compared according to genotypes by additive, dominant, and recessive genetic models. Bulbar onset was overrepresented among carriers of the AA risk genotype, together with enhanced upper motor neuron involvement and poorer functional status in patients harboring at least one major risk allele (A). In a subset of 195 patients, we found that the homozygotes for the minor allele (GG) showed lower scores at the Edinburgh Cognitive and Behavioral Amyotrophic Lateral Sclerosis Screen, indicating a more severe cognitive impairment, mainly involving the amyotrophic lateral sclerosis-specific cognitive functions and memory. Moreover, lower motor neuron burden predominated among patients with at least one minor allele (G). Overall, we found that TMEM106B is a disease modifier of amyotrophic lateral sclerosis, whose phenotypic effects encompass both sites of onset and functional status (major risk allele), motor functions (both major risk and minor alleles), and cognition (minor allele).

Psychometrics, diagnostics and usability of Italian tools assessing behavioural and functional outcomes in neurological, geriatric and psychiatric disorders: a systematic review

Background

Psychometric instruments assessing behavioural and functional outcomes (BFIs) in neurological, geriatric and psychiatric populations are relevant towards diagnostics, prognosis and intervention. However, BFIs often happen not to meet methodological-statistical standards, thus lowering their level of recommendation in clinical practice and research. This work thus aimed at (1) providing an up-to-date compendium on psychometrics, diagnostics and usability of available Italian BFIs and (2) delivering evidence-based information on their level of recommendation.

Methods

This review was pre-registered (PROSPERO ID: CRD42021295430) and performed according to PRISMA guidelines. Several psychometric, diagnostic and usability measures were addressed as outcomes. Quality assessment was performed via an ad hoc checklist, the Behavioural and Functional Instrument Quality Assessment.

Results

Out of an initial N = 830 reports, 108 studies were included (N = 102 BFIs). Target constructs included behavioural/psychiatric symptoms, quality of life and physical functioning. BFIs were either self- or caregiver-/clinician-report. Studies in clinical conditions (including neurological, psychiatric and geriatric ones) were the most represented. Validity was investigated for 85 and reliability for 80 BFIs, respectively. Criterion and factorial validity testing were infrequent, whereas content and ecological validity and parallel forms were almost never addressed. Item response theory analyses were seldom carried out. Diagnostics and norms lacked for about one-third of BFIs. Information on administration time, ease of use and ceiling/floor effects were often unreported.

Discussion

Several available BFIs for the Italian population do not meet adequate statistical-methodological standards, this prompting a greater care from researchers involved in their development.

Supplementary Information

The online version contains supplementary material available at 10.1007/s10072-022-06300-8.

Early Identification of Different Behavioral Phenotypes in the Behavioral Variant of Frontotemporal Dementia with the Aid of the Mini-Frontal Behavioral Inventory (mini-FBI)

Background: The Frontal Behavioral Inventory (FBI) is a questionnaire designed to quantify behavioral changes in frontotemporal dementia (FTD). Literature showed heterogeneous FBI profiles in FTD versus Alzheimer’s disease (AD) with variable occurrence of positive and negative symptoms. Objective: In this study, we constructed a short FBI version (i.e., mini-FBI) with the aim to provide clinicians with a short tool for the identification of early behavioral changes in behavioral variant of FTD (bvFTD), also facilitating the differential diagnosis with AD. Methods: 40 bvFTD and 33 AD patients were enrolled. FBI items were selected based on internal consistency and exploratory factor analysis. Convergent validity of mini-FBI was also assessed. A behavioral index (i.e., B-index) representing the balance between positive and negative mini-FBI symptoms was computed in order to analyze its distribution in bvFTD through a cluster analysis and to compare performance among patient groups. Results: The final version of the mini-FBI included 12 items, showing a significant convergent validity with the Neuropsychiatric Inventory scores (rp = 0.61, p < 0.001). Cluster analysis split patients in four clusters. bvFTD were included in three different clusters characterized by prevalent positive symptoms, both positive and negative symptoms, or prevalent negative behavioral alterations, similar to a subset of AD patients. A fourth cluster included only AD patients showing no positive symptoms. Conclusion: The mini-FBI is a valuable easily administrable questionnaire able to early identify symptoms effectively contributing to the bvFTD behavioral syndrome, aiding clinician in diagnosis and management.

Profiling morphologic MRI features of motor neuron disease caused by TARDBP mutations

Objective

Mutations in the TARDBP gene are a rare cause of genetic motor neuron disease (MND). Morphologic MRI characteristics of MND patients carrying this mutation have been poorly described. Our objective was to investigate distinctive clinical and MRI features of a relatively large sample of MND patients carrying TARDBP mutations.

Methods

Eleven MND patients carrying a TARDBP mutation were enrolled. Eleven patients with sporadic MND (sMND) and no genetic mutations were also selected and individually matched by age, sex, clinical presentation and disease severity, along with 22 healthy controls. Patients underwent clinical and cognitive evaluations, as well as 3D T1-weighted and diffusion tensor (DT) MRI on a 3 Tesla scanner. Gray matter (GM) atrophy was first investigated at a whole-brain level using voxel-based morphometry (VBM). GM volumes and DT MRI metrics of the main white matter (WM) tracts were also obtained. Clinical, cognitive and MRI features were compared between groups.

Results

MND with TARDBP mutations was associated with all possible clinical phenotypes, including isolated upper/lower motor neuron involvement, with no predilection for bulbar or limb involvement at presentation. Greater impairment at naming tasks was found in TARDBP mutation carriers compared with sMND. VBM analysis showed significant atrophy of the right lateral parietal cortex in TARDBP patients, compared with controls. A distinctive reduction of GM volumes was found in the left precuneus and right angular gyrus of TARDBP patients compared to controls. WM microstructural damage of the corticospinal tract (CST) and inferior longitudinal fasciculi (ILF) was found in both sMND and TARDBP patients, compared with controls, although decreased fractional anisotropy of the right CST and increased axial diffusivity of the left ILF (p = 0.017) was detected only in TARDBP mutation carriers.

Conclusions

TARDBP patients showed a distinctive parietal pattern of cortical atrophy and greater damage of motor and extra-motor WM tracts compared with controls, which sMND patients matched for disease severity and clinical presentation were lacking. Our findings suggest that TDP-43 pathology due to TARDBP mutations may cause deeper morphologic alterations in both GM and WM.

Personal space regulation is affected by unilateral temporal lesions beyond the amygdala

We constantly face situations involving interactions with others that require us to automatically adjust our physical distances to avoid discomfort or anxiety. A previous case study has demonstrated that the integrity of both amygdalae is essential to regulate interpersonal distances. Despite unilateral lesion to the amygdala, as to other sectors of the medial temporal cortex, are known to also affect social behavior, their role in the regulation of interpersonal distances has never been investigated. Here, we sought to fill this gap by testing three patients with unilateral temporal lesions following surgical resections, including one patient with a lesion mainly centered on the amygdala and two with lesions to adjacent medial temporal cortex, on two versions of the stop distance paradigm (i.e. in a virtual reality environment and in a real setting). Our results showed that all three patients set shorter interpersonal distances compared to neurotypical controls. In addition, compared to controls, none of the patients adjusted such physical distances depending on facial emotional expressions, despite they preserved ability to categorize them. Finally, patients' heart rate responses differed from controls when viewing approaching faces. Our findings bring compelling evidence that unilateral lesions within the medial temporal cortex, not necessarily restricted to the amygdala, are sufficient to alter interpersonal distance, thus shedding new light on the neural circuitry regulating distance in social interactions.

Upper motor neuron dysfunction is associated with the presence of behavioural impairment in patients with amyotrophic lateral sclerosis

BACKGROUND AND PURPOSE

Increasing evidence shows that approximately half of patients with amyotrophic lateral sclerosis (ALS) display cognitive (ALSci) or behavioural (ALSbi) impairment, or both (ALScbi). The aim of our study was to assess whether the burden of upper and lower motor neuron involvement is associated with the presence of cognitive and behavioural impairment.

METHODS

A single-centre retrospective cohort of 110 Italian ALS patients was evaluated to assess correlations between motor and cognitive/behavioural phenotypes. Upper motor neuron regional involvement was measured with the Penn Upper Motor Neuron Score (PUMNS), whilst lower motor neuron signs were assessed using the Lower Motor Neuron Score. The Edinburgh Cognitive and Behavioural ALS Screen-Italian version and the Frontal Behaviour Inventory were administered to evaluate patients' cognitive and behavioural profiles.

RESULTS

The PUMNS at first visit was significantly higher in behaviourally impaired ALS patients (ALSbi and ALScbi) compared to behaviourally unimpaired individuals (ALS and ALSci) (9.9 vs. 6.9, p = 0.014). Concerning the different Frontal Behaviour Inventory subdomains, higher PUMNS correlated with the presence of apathy, emotive indifference, inflexibility, inattention, perseveration and aggressiveness.

CONCLUSION

To our knowledge, this is the first study showing that a clinical prominent upper motor neuron dysfunction is associated with a more significant behavioural impairment in ALS patients, suggesting the hypothesis of a preferential spreading of the pathology from the motor cortex to the ventromedial prefrontal and orbitofrontal cortex in this group of patients.

Resting state functional brain networks associated with emotion processing in frontotemporal lobar degeneration

This study investigated the relationship between emotion processing and resting-state functional connectivity (rs-FC) of the brain networks in frontotemporal lobar degeneration (FTLD). Eighty FTLD patients (including cases with behavioral variant of frontotemporal dementia, primary progressive aphasia, progressive supranuclear palsy syndrome, motor neuron disease) and 65 healthy controls underwent rs-functional MRI. Emotion processing was tested using the Comprehensive Affect Testing System (CATS). In patients and controls, correlations were investigated between each emotion construct and rs-FC changes within critical networks. Mean rs-FC of the clusters significantly associated with CATS scoring were compared among FTLD groups. FTLD patients had pathological CATS scores compared with controls. In controls, increased rs-FC of the cerebellar and visuo-associative networks correlated with better scores in emotion-matching and discrimination tasks, respectively; while decreased rs-FC of the visuo-spatial network was related with better performance in the affect-matching and naming. In FTLD, the associations between rs-FC and CATS scores involved more brain regions, such as orbitofrontal and middle frontal gyri within anterior networks (i.e., salience and default-mode), parietal and somatosensory regions within visuo-spatial and sensorimotor networks, caudate and thalamus within basal-ganglia network. Rs-FC changes associated with CATS were similar among all FTLD groups. In FTLD compared to controls, the pattern of rs-FC associated with emotional processing involves a larger number of brain regions, likely due to functional specificity loss and compensatory attempts. These associations were similar across all FTLD groups, suggesting a common physiopathological mechanism of emotion processing breakdown, regardless the clinical presentation and pattern of atrophy.

A systematic review of non-motor symptom evaluation in clinical trials for amyotrophic lateral sclerosis

BACKGROUND

Amyotrophic lateral sclerosis (ALS) is increasingly recognised as a multi-system disorder, presenting with common and impactful non-motor symptoms, such as neuropsychiatric symtpoms, cognitive and behavioural changes, pain, disordered sleep, fatigue and problematic saliva.

AIM/HYPOTHESIS

We aimed to systematically review 25 years of ALS clinical trials data to identify if non-motor features were evaluated, in addition to the traditional measures of motor functioning and survival, and where evaluated to describe the instruments used to assess. We hypothesised that assessment of non-motor symptoms has been largely neglected in trial design and not evaluated with ALS-suitable instruments.

METHODS

We reviewed clinical trials of investigative medicinal products in ALS, since the licensing of riluzole in 1994. Trial registry databases including WHO International Trials Registry, European Clinical Trials Register, clinicaltrials.gov, and PubMed were systematically searched for Phase II, III or IV trials registered, completed or published between 01/01/1994 and 16/09/2020. No language restrictions were applied.

RESULTS

237 clinical trials, including over 29,222 participants, were investigated for their use of non-motor outcome measures. These trials evaluated neuropsychiatric symptoms (75, 32%), cognitive impairment (16, 6.8%), behavioural change (34, 14%), pain (55, 23%), sleep disturbances (12, 5%) and fatigue (18, 8%). Problematic saliva was assessed as part of composite ALS-FRS(R) scores in 184 trials (78%) but with no focus on this as an isolated symptom. 31 (13%) trials including 3585 participants did not include any assessment of non-motor symptoms.

CONCLUSIONS

Non-motor symptoms such as neuropsychiatric, cognitive and behavioural changes, pain, disordered sleep, fatigue, and problematic saliva have not been consistently evaluated in trials for people with ALS. Where evaluated, non-symptoms were primarily assessed using instruments and impairment thresholds that are not adapted for people with ALS. Future trials should include non-motor symptom assessments to evaluate the additional potential therapeutic benefit of candidate drugs.

PROPSERO REGISTRATION

CRD42020223648.

Social Cognition and Behavioral Assessments Improve the Diagnosis of Behavioral Variant of Frontotemporal Dementia in Older Peruvians With Low Educational Levels

Background: The behavioral variant of frontotemporal dementia (bvFTD), characterized by early behavioral abnormalities and late memory impairment, is a neurodegenerative disorder with a detrimental impact on patients and their caregivers. bvFTD is often difficult to distinguish from other neurodegenerative diseases, such as Alzheimer's disease (AD), using brief cognitive tests. Combining brief socio-cognitive and behavioral evaluations with standard cognitive testing could better discriminate bvFTD from AD patients. We sought to evaluate the diagnostic accuracy of brief socio-cognitive tests that may differentiate bvFTD and AD patients with low educational levels. Methods: A prospective study was performed on 51 individuals over the age of 50 with low educational levels, with bvFTD or AD diagnosed using published criteria, and who were receiving neurological care at a multidisciplinary neurology clinic in Lima, Peru, between July 2017 and December 2020. All patients had a comprehensive neurological evaluation, including a full neurocognitive battery and brief tests of cognition (Addenbrooke's Cognitive Examination version III, ACE-III), social cognition (Mini-social Cognition and Emotional Assessment, Mini-SEA), and behavioral assessments (Frontal Behavioral Inventory, FBI; Interpersonal Reactivity Index-Emphatic Concern, IRI-EC; IRI-Perspective Taking, IRI-PT; and Self-Monitoring Scale-revised version, r-SMS). Receiver operating characteristic (ROC) analysis to calculate the area under the curve (AUC) was performed to compare the brief screening tests individually and combined to the gold standard of bvFTD and AD diagnoses. Results: The AD group was significantly older than the bvFTD group (p < 0.001). An analysis of the discriminatory ability of the ACE-III to distinguish between patients with AD and bvFTD (AUC = 0.85) and the INECO Frontal Screening (IFS; AUC = 0.78) shows that the former has greater discriminatory ability. Social and behavioral cognition tasks were able to appropriately discriminate bvFTD from AD. The Mini-SEA had high sensitivity and high moderate specificity (83%) for discriminating bvFTD from AD, which increased when combined with the brief screening tests ACE-III and IFS. The FBI was ideal with high sensitivity (83%), as well as the IRI-EC and IRI-PT that also were adequate for distinguishing bvFTD from AD. Conclusions: Our study supports the integration of socio-behavioral measures to the standard global cognitive and social cognition measures utilized for screening for bvFTD in a population with low levels of education.

Italian adaptation of the Beaumont Behavioral Inventory (BBI): psychometric properties and clinical usability

Objective. Up to 50% of patients affected by amyotrophic lateral sclerosis (ALS) show behavioral changes within the spectrum of frontotemporal degeneration (FTD). Behavioral dysfunctions in ALS patients negatively impact on management, prognosis and survival. It is, thus, crucial to develop ALS-specific psychometric tools for early detecting alterations in behavior. This study aimed at investigating psychometric properties and feasibility of the Beaumont Behavioral Impairment (BBI), a proxy-report questionnaire designed to screen for FTD-like behavioral symptoms in ALS patients.Methods. Ninety ALS patients were compared to 100 healthy participants (HPs) on the BBI. ALS patients underwent clinical, cognitive, mood/anxiety and further behavioral (Frontal System Behavior Scale, FrSBe; Frontal Behavioral Inventory, FBI) evaluation. Validity, reliability, sensitivity and specificity of the BBI were assessed.Results. The BBI was significantly related to FrSBe and FBI scores, whereas not to other measures. A Principal Component Analysis yielded a mono-component structure; Cronbach's α was .93. The BBI proved to be sensitive to changes in behavior as well as to discriminate between different degrees of dysfunction. By addressing the FrSBe as the gold standard, the BBI reached optimal sensitivity (85.7%) and specificity (79.7%) at a cutoff of 10.5. Moreover, the BBI proved to be more accurate than the FrSBe and the FBI in clinical classifications.Conclusion. The BBI showed high internal consistency, as well as good construct, convergent and divergent validity. Its clinical usability is encouraged in ALS patients as being able to sensitively and specifically detect FTD-like behavioral changes.

Neurophysiological Correlates of Positive and Negative Symptoms in Frontotemporal Dementia

BACKGROUND

The neural correlates of behavioral symptoms in frontotemporal dementia (FTD) are still to be elucidated. Neurotransmitter abnormalities could be correlated to the pathophysiology of negative and positive symptoms in FTD.

OBJECTIVE

To evaluate if the imbalance between inhibitory and excitatory cortical circuits, evaluated with transcranial magnetic stimulation (TMS), correlate with the magnitude of negative and positive symptoms, as measured by Frontal Behavioral Inventory (FBI) scores, in patients with FTD.

METHODS

Paired-pulse TMS was used to investigate the activity of different intracortical circuits in 186 FTD patients (130 bvFTD, 35 avPPA, 21 svPPA). We applied short interval intracortical inhibition (SICI - GABAAergic transmission), intracortical facilitation (ICF - glutamatergic transmission), long interval intracortical inhibition (LICI - GABABergic transmission), and short latency afferent inhibition (SAI - cholinergic transmission). Linear and stepwise multiple regression analysis were used to determine the contribution of each neurophysiological measures to the total variance of FBI scores.

RESULTS

At the stepwise multivariate analysis, we observed a significant negative correlation between FBI-A scores (negative symptoms) and ICF (β = -0.57, p < 0.001, adjusted R2 = 0.32). For FBI-B scores (positive symptoms), we observed a significant positive correlation for SICI (β = 0.84, p < 0.001, adjusted R2 = 0.56). Significant correlations were observed for single items of the FBI-A score with ICF and FBI-B scores with SICI, with a medium-large size effect for several items.

CONCLUSIONS

The present study shows that the imbalance between inhibitory and excitatory intracortical circuits, evaluated with TMS, correlated with the magnitude of negative and positive symptoms in FTD, respectively.

Compensating for verbal-motor deficits in neuropsychological assessment in movement disorders: sensitivity and specificity of the ECAS in Parkinson's and Huntington's diseases

INTRODUCTION

The study aims at investigating psychometric properties of the Edinburgh cognitive and behavioural ALS screen (ECAS) in Parkinson's (PD) and Huntington's (HD) diseases. The sensitivity and specificity of the ECAS in highlighting HD and PD cognitive-behavioural features and in differentiating between these two populations and from healthy controls (HC) were evaluated. Moreover, correlations between the ECAS and traditional cognitive measures, together with core clinical features, were analysed.

METHODS

Seventy-three PD patients, 38 HD patients, and 49 education-matched healthy participants were enrolled. Participants were administered the ECAS, together with other cognitive screening tools and psychological questionnaires. Patients' behavioural assessment was also carried out with carers.

RESULTS

The ECAS distinguished between HD patients and HC and between the two clinical syndromes with high sensitivity and specificity. Even if the diagnostic accuracy of the ECAS in distinguishing between PD and HC was low, the PD cognitive phenotype was very well described by the ECAS performances. Convergent validity of the ECAS against other traditional cognitive screening was observed, as well as correlations with psychological aspects and typical clinical features, especially for the HD group.

CONCLUSIONS

The ECAS represents a rapid and feasible tool, useful also in other neurodegenerative disorders affecting verbal-motor abilities than the amyotrophic lateral sclerosis such as PD and HD. Clinical applications in these neurodegenerative conditions require further investigations and, probably, some adaptations of the original test.

Progression of Behavioral Disturbances and Neuropsychiatric Symptoms in Patients With Genetic Frontotemporal Dementia

IMPORTANCE

Behavioral disturbances are core features of frontotemporal dementia (FTD); however, symptom progression across the course of disease is not well characterized in genetic FTD.

OBJECTIVE

To investigate behavioral symptom frequency and severity and their evolution and progression in different forms of genetic FTD.

DESIGN, SETTING, AND PARTICIPANTS

This longitudinal cohort study, the international Genetic FTD Initiative (GENFI), was conducted from January 30, 2012, to May 31, 2019, at 23 multicenter specialist tertiary FTD research clinics in the United Kingdom, the Netherlands, Belgium, France, Spain, Portugal, Italy, Germany, Sweden, Finland, and Canada. Participants included a consecutive sample of 232 symptomatic FTD gene variation carriers comprising 115 with variations in C9orf72, 78 in GRN, and 39 in MAPT. A total of 101 carriers had at least 1 follow-up evaluation (for a total of 400 assessments). Gene variations were included only if considered pathogenetic.

MAIN OUTCOMES AND MEASURES

Behavioral and neuropsychiatric symptoms were assessed across disease duration and evaluated from symptom onset. Hierarchical generalized linear mixed models were used to model behavioral and neuropsychiatric measures as a function of disease duration and variation.

RESULTS

Of 232 patients with FTD, 115 (49.6%) had a C9orf72 expansion (median [interquartile range (IQR)] age at evaluation, 64.3 [57.5-69.7] years; 72 men [62.6%]; 115 White patients [100%]), 78 (33.6%) had a GRN variant (median [IQR] age, 63.4 [58.3-68.8] years; 40 women [51.3%]; 77 White patients [98.7%]), and 39 (16.8%) had a MAPT variant (median [IQR] age, 56.3 [49.9-62.4] years; 25 men [64.1%]; 37 White patients [94.9%]). All core behavioral symptoms, including disinhibition, apathy, loss of empathy, perseverative behavior, and hyperorality, were highly expressed in all gene variant carriers (>50% patients), with apathy being one of the most common and severe symptoms throughout the disease course (51.7%-100% of patients). Patients with MAPT variants showed the highest frequency and severity of most behavioral symptoms, particularly disinhibition (79.3%-100% of patients) and compulsive behavior (64.3%-100% of patients), compared with C9orf72 carriers (51.7%-95.8% of patients with disinhibition and 34.5%-75.0% with compulsive behavior) and GRN carriers (38.2%-100% with disinhibition and 20.6%-100% with compulsive behavior). Alongside behavioral symptoms, neuropsychiatric symptoms were very frequently reported in patients with genetic FTD: anxiety and depression were most common in GRN carriers (23.8%-100% of patients) and MAPT carriers (26.1%-77.8% of patients); hallucinations, particularly auditory and visual, were most common in C9orf72 carriers (10.3%-54.5% of patients). Most behavioral and neuropsychiatric symptoms increased in the early-intermediate phases and plateaued in the late stages of disease, except for depression, which steadily declined in C9orf72 carriers, and depression and anxiety, which surged only in the late stages in GRN carriers.

CONCLUSIONS AND RELEVANCE

This cohort study suggests that behavioral and neuropsychiatric disturbances differ between the common FTD gene variants and have different trajectories throughout the course of disease. These findings have crucial implications for counseling patients and caregivers and for the design of disease-modifying treatment trials in genetic FTD.

Structural and functional brain connectome in motor neuron diseases: A multicenter MRI study

OBJECTIVE

To investigate structural and functional neural organization in amyotrophic lateral sclerosis (ALS), primary lateral sclerosis (PLS), and progressive muscular atrophy (PMA).

METHODS

A total of 173 patients with sporadic ALS, 38 patients with PLS, 28 patients with PMA, and 79 healthy controls were recruited from 3 Italian centers. Participants underwent clinical, neuropsychological, and brain MRI evaluations. Using graph analysis and connectomics, global and lobar topologic network properties and regional structural and functional brain connectivity were assessed. The association between structural and functional network organization and clinical and cognitive data was investigated.

RESULTS

Compared with healthy controls, patients with ALS and patients with PLS showed altered structural global network properties, as well as local topologic alterations and decreased structural connectivity in sensorimotor, basal ganglia, frontal, and parietal areas. Patients with PMA showed preserved global structure. Patient groups did not show significant alterations of functional network topologic properties relative to controls. Increased local functional connectivity was observed in patients with ALS in the precentral, middle, and superior frontal areas, and in patients with PLS in the sensorimotor, basal ganglia, and temporal networks. In patients with ALS and patients with PLS, structural connectivity alterations correlated with motor impairment, whereas functional connectivity disruption was closely related to executive dysfunction and behavioral disturbances.

CONCLUSIONS

This multicenter study showed widespread motor and extramotor network degeneration in ALS and PLS, suggesting that graph analysis and connectomics might represent a powerful approach to detect upper motor neuron degeneration, extramotor brain changes, and network reorganization associated with the disease. Network-based advanced MRI provides an objective in vivo assessment of motor neuron diseases, delivering potential prognostic markers.

Serum Glial Fibrillary Acidic Protein (GFAP) Is a Marker of Disease Severity in Frontotemporal Lobar Degeneration

Background: It is still unknown if serum glial fibrillary acidic protein (GFAP) is a useful marker in frontotemporal lobar degeneration (FTLD). Objective: To assess the diagnostic and prognostic value of serum GFAP in a large cohort of patients with FTLD. Methods: In this retrospective study, performed on 406 participants, we measured serum GFAP concentration with an ultrasensitive Single molecule array (Simoa) method in patients with FTLD, Alzheimer’s disease (AD), and in cognitively unimpaired elderly controls. We assessed the role of GFAP as marker of disease severity by analyzing the correlation with clinical variables, neurophysiological data, and cross-sectional brain imaging. Moreover, we evaluated the role of serum GFAP as a prognostic marker of disease survival. Results: We observed significantly higher levels of serum GFAP in patients with FTLD syndromes, except progressive supranuclear palsy, compared with healthy controls, but not compared with AD patients. In FTLD, serum GFAP levels correlated with measures of cognitive dysfunction and disease severity, and were associated with indirect measures of GABAergic deficit. Serum GFAP concentration was not a significant predictor of survival. Conclusion: Serum GFAP is increased in FTLD, correlates with cognition and GABAergic deficits, and thus shows promise as a biomarker of disease severity in FTLD.

Unraveling Moral Reasoning in Amyotrophic Lateral Sclerosis: How Emotional Detachment Modifies Moral Judgment

In the last decade, scientific literature provided solid evidence of cognitive deficits in amyotrophic lateral sclerosis (ALS) patients and their effects on end-life choices. However, moral cognition and judgment are still poorly investigated in this population. Here we aimed at evaluating both socio-cognitive and socio-affective components of moral reasoning in a sample of 28 ALS patients. Patients underwent clinical and neuropsychological evaluation including basic cognitive and social cognition measures. Additionally, we administered an experimental task including moral dilemmas, with instrumental and incidental conditions. Patients’ performances were compared with a control group [healthy control (HC)], including 36 age-, gender-, and education-matched healthy subjects. Despite that the judgment pattern was comparable in ALS and HC, patients resulted less prone to carry out a moral transgression compared to HC. Additionally, ALS patients displayed higher levels of moral permissibility and lower emotional arousal, with similar levels of engagement in both instrumental and incidental conditions. Our findings expanded the current literature about cognitive deficits in ALS, showing that in judging moral actions, patients may present non-utilitarian choices and emotion flattening. Such a decision-making profile may have relevant implications in applying moral principles in real-life situations and for the judgment of end-of-life treatments and care in clinical settings.

Recommendations to distinguish behavioural variant frontotemporal dementia from psychiatric disorders

The behavioural variant of frontotemporal dementia (bvFTD) is a frequent cause of early-onset dementia. The diagnosis of bvFTD remains challenging because of the limited accuracy of neuroimaging in the early disease stages and the absence of molecular biomarkers, and therefore relies predominantly on clinical assessment. BvFTD shows significant symptomatic overlap with non-degenerative primary psychiatric disorders including major depressive disorder, bipolar disorder, schizophrenia, obsessive-compulsive disorder, autism spectrum disorders and even personality disorders. To date, ∼50% of patients with bvFTD receive a prior psychiatric diagnosis, and average diagnostic delay is up to 5-6 years from symptom onset. It is also not uncommon for patients with primary psychiatric disorders to be wrongly diagnosed with bvFTD. The Neuropsychiatric International Consortium for Frontotemporal Dementia was recently established to determine the current best clinical practice and set up an international collaboration to share a common dataset for future research. The goal of the present paper was to review the existing literature on the diagnosis of bvFTD and its differential diagnosis with primary psychiatric disorders to provide consensus recommendations on the clinical assessment. A systematic literature search with a narrative review was performed to determine all bvFTD-related diagnostic evidence for the following topics: bvFTD history taking, psychiatric assessment, clinical scales, physical and neurological examination, bedside cognitive tests, neuropsychological assessment, social cognition, structural neuroimaging, functional neuroimaging, CSF and genetic testing. For each topic, responsible team members proposed a set of minimal requirements, optimal clinical recommendations, and tools requiring further research or those that should be developed. Recommendations were listed if they reached a ≥ 85% expert consensus based on an online survey among all consortium participants. New recommendations include performing at least one formal social cognition test in the standard neuropsychological battery for bvFTD. We emphasize the importance of 3D-T1 brain MRI with a standardized review protocol including validated visual atrophy rating scales, and to consider volumetric analyses if available. We clarify the role of 18F-fluorodeoxyglucose PET for the exclusion of bvFTD when normal, whereas non-specific regional metabolism abnormalities should not be over-interpreted in the case of a psychiatric differential diagnosis. We highlight the potential role of serum or CSF neurofilament light chain to differentiate bvFTD from primary psychiatric disorders. Finally, based on the increasing literature and clinical experience, the consortium determined that screening for C9orf72 mutation should be performed in all possible/probable bvFTD cases or suspected cases with strong psychiatric features.

The unidimensionality of the five Brain Injury Rehabilitation Trust Personality Questionnaires (BIRT-PQs) may be improved: preliminary evidence from classical psychometrics

Objective: To assess the internal construct validity (ICV) of the five Brain Injury Rehabilitation Trust Personality Questionnaires (BIRT-PQ) with Classical Test Theory methods.Methods: Multicenter cross-sectional study involving 11 Italian rehabilitation centers. BIRT-PQs were administered to patients with severe Acquired Brain Injury and their respective caregivers. ICV was assessed by the mean of an internal consistency analysis (ICA) and a Confirmatory Factor Analysis (CFA).Results: Data from 154 patients and their respective caregivers were pooled, giving a total sample of 308 subjects. Despite good overall values (alphas ranging from 0.811 to 0.937), the ICA revealed that several items within each scale did not contribute as expected to the total score. This result was confirmed by the CFA, which showed the misfit of the data to a unidimensional model (RMSEA ranging from 0.077 to 0.097). However, after accounting for local dependency found within the data, fitness to a unidimensional model improved significantly (RMSEA ranging from 0.050 to 0.062).Conclusion: Despite some limitations, our analyses demonstrated the lack of ICV for the BIRT-PQ total scores. It is envisaged that a more comprehensive ICV analysis will be performed with Rasch analysis, aiming to improve both the measurement properties and the administrative burden of each BIRT-PQ.

Cortical correlates of behavioural change in amyotrophic lateral sclerosis

BACKGROUND

Behavioural changes in amyotrophic lateral sclerosis (ALS) are heterogeneous. The study aim was to identify the behavioural profiles of non-demented patients with ALS and their neuroimaging correlates and to elucidate if they are comparable to those reported in studies of the behavioural-variant of frontotemporal dementia (bvFTD).

METHODS

Behavioural changes of 102 non-demented patients with ALS were assessed through the Frontal Behavioural Inventory (FBI), a 24-item scale assessing different behavioural modifications, mainly chosen from the core clinical features of FTD. Principal component analysis (PCA) was used to detect distinct clusters of behavioural changes based on FBI subscores. The cortical thinning related to each behavioural profile was analysed in 29 patients with ALS. Cronbach's α was used to test the reliability of bvFTD-related FBI clustering in our cohort.

RESULTS

Sixty patients with ALS had FBI score≥1. PCA identified three phenotypic clusters loading on disinhibited/hostile, dysexecutive and apathetic FBI subscores. Imaging analyses revealed that the thinning of bilateral orbitofrontal cortex was related to apathy, the right frontotemporal and cingular cortex to the disinhibited/hostile profile and the left precuneus cortex to the dysexecutive behaviours. The bvFTD-associated aggressive profile reliably applied to our cohort.

CONCLUSIONS

In non-demented patients with ALS, different behavioural profiles could be identified. The right frontotemporal and cingular cortex thinning was the hallmark of the behavioural profile mostly overlapping that described in bvFTD. Our findings provide the unbiased identification of determinants relevant for a novel stratification of patients with ALS based on their behavioural impairment, which might be useful as proxy of cognitive decline.

Brain MRI shows white matter sparing in Kennedy's disease and slow-progressing lower motor neuron disease

The extent of central nervous system involvement in Kennedy's disease (KD) relative to other motor neuron disease (MND) phenotypes still needs to be clarified. In this study, we investigated cortical and white matter (WM) MRI alterations in 25 patients with KD, compared with 24 healthy subjects, 25 patients with sporadic amyotrophic lateral sclerosis (ALS), and 35 cases with lower motor neuron-predominant disease (LMND). LMND patients were clinically differentiated into 24 fast and 11 slow progressors. Whole-brain cortical thickness, WM tract-based spatial statistics and corticospinal tract (CST) tractography analyses were performed. No significant difference in terms of cortical thickness was found between groups. ALS patients showed widespread decreased fractional anisotropy and increased mean (MD) and radial diffusivity (radD) in the CST, corpus callosum and fronto-temporal extra-motor tracts, compared with healthy controls and other patient groups. CST tractography showed significant alterations of DT MRI metrics in ALS and LMND-fast patients whereas KD and LMND-slow patients were comparable with healthy controls. Our study demonstrated the absence of WM abnormalities in patients with KD and LMND-slow, in contrast with diffuse WM damage in ALS and focal CST degeneration in LMND-fast, supporting the use of DT MRI measures as powerful tools to differentiate fast- and slow-progressing MND syndromes, including KD.

The language profile of progressive supranuclear palsy

A progressive speech/language disorder, such as the non fluent/agrammatic variant of primary progressive aphasia and progressive apraxia of speech, can be due to neuropathologically verified Progressive Supranuclear Palsy (PSP). The prevalence of linguistic deficits and the linguistic profile in PSP patients who present primarily with a movement disorder is unknown. In the present study, we investigated speech and language performance in a sample of clinically diagnosed PSP patients using a comprehensive language battery, including, besides traditional language tests, a detailed analysis of connected speech (picture description task assessing 26 linguistic features). The aim was to identify the most affected linguistic levels in seventeen PSP with a movement disorder presentation, compared to 21 patients with Parkinson's disease and 27 healthy controls. Machine learning methods were used to detect the most relevant language tests and linguistic features characterizing the language profile of PSP patients. Our results indicate that even non-clinically aphasic PSP patients have subtle language deficits, in particular involving the lexical-semantic and discourse levels. Patients with the Richardson's syndrome showed a lower performance in the word comprehension task with respect to the other PSP phenotypes with predominant frontal presentation, parkinsonism and progressive gait freezing. The present findings support the usefulness of a detailed language assessment in all patients in the PSP spectrum.

Combined Socio-Behavioral Evaluation Improves the Differential Diagnosis Between the Behavioral Variant of Frontotemporal Dementia and Alzheimer's Disease: In Search of Neuropsychological Markers

BACKGROUND

Current diagnostic criteria for behavioral variant of frontotemporal dementia (bvFTD) and typical Alzheimer's disease (AD) include a differential pattern of neuropsychological impairments (episodic memory deficit in typical AD and dysexecutive syndrome in bvFTD). There is, however, large evidence of a frequent overlap in neuropsychological features, making the differential diagnosis extremely difficult.

OBJECTIVES

In this retrospective study, we evaluated the diagnostic value of different cognitive and neurobehavioral markers in bvFTD and AD patient groups.

METHODS

We included 95 dementia patients with a clinical and biomarker evidence of bvFTD (n = 48) or typical AD (n = 47) pathology. A clinical 2-year follow-up confirmed clinical classification. Performances at basic cognitive tasks (memory, executive functions, visuo-spatial, language) as well as social cognition skills and neurobehavioral profiles have been recorded. A stepwise logistic regression model compared the neuropsychological profiles between groups and assessed the accuracy of cognitive and neurobehavioral markers in discriminating bvFTD from AD.

RESULTS

Statistical comparison between patient groups proved social cognition and episodic memory impairments as main cognitive signatures of bvFTD and AD neuropsychological profiles, respectively. Only half of bvFTD patients showed attentive/executive deficits, questioning their role as cognitive marker of bvFTD. Notably, the large majority of bvFTD sample (i.e., 70%) poorly performed at delayed recall tasks. Logistic regression analysis identified social cognition performances, Frontal Behavioral Inventory and Mini-Mental State Examination scores as the best combination in distinguishing bvFTD from AD.

CONCLUSION

Social cognition tasks and socio-behavioral questionnaires are recommended in clinical settings to improve the accuracy of early diagnosis of bvFTD.

Closing-in Behavior and Parietal Lobe Deficits: Three Single Cases Exhibiting Different Manifestations of the Same Behavior

Closing-in behavior (CIB) is observed in copying tasks (graphic or gestural) when the copy is performed near or on the top of the model. This symptom has been classically considered to be a manifestation of constructional apraxia and is often associated with a visuospatial impairment. More recent work emphasizes the attentional and/or executive nature of the behavior and its association with frontal lobe dysfunction. We describe three patients in whom CIB was associated with posterior parietal deficits of different etiologies (stroke in Patient 1 and dementia in Patients 2 and 3). In copying figures, Patient 1 produced the shape with high accuracy but the rendering overlapped the model, while for Patients 2 and 3 the copies were distorted but overlapping or in close proximity to the target. In gesture imitation, Patient 2 performed the gestures toward the examiner's space, while Patient 1 showed a peculiar form of CIB: when he was asked to place the ipsilesional arm in a position that mirrored the contralesional hand, Patient 1 moved his hand toward his contralesional hand. Patient 3 did not present gestural CIB. While CIB in Patient 1 was associated with selective deficits in executive functions and attention, additional visuospatial deficits were observed in Patients 2 and 3. The latter two patients showed a general visuoconstructional deficit. These case studies support a primary attentional account of CIB but also suggest that visuoconstructional impairments may contribute to the emergence of CIB, in some subjects. This evidence argues for different types of CIB with different cognitive and neural underpinnings. Furthermore, the data support the hypothesis of a differential involvement of fronto-parietal network in CIB.

The Arrows and Colors Cognitive Test (ACCT): A new verbal-motor free cognitive measure for executive functions in ALS

Background and objective

The presence of executive deficits in patients with Amyotrophic Lateral Sclerosis is well established, even if standardized measures are difficult to obtain due to progressive physical disability of the patients. We present clinical data concerning a newly developed measure of cognitive flexibility, administered by means of Eye-Tracking (ET) technology in order to bypass verbal-motor limitations.

Methods

21 ALS patients and 21 age-and education-matched healthy subjects participated in an ET-based cognitive assessment, including a newly developed test of cognitive flexibility (Arrows and Colors Cognitive Test–ACCT) and other oculomotor-driven measures of cognitive functions. A standard screening of frontal and working memory abilities and global cognitive efficiency was administered to all subjects, in addition to a psychological self-rated assessment. For ALS patients, a clinical examination was also performed.

Results

ACCT successfully discriminated between patients and healthy controls, mainly concerning execution times obtained at different subtests. A qualitative analysis performed on error distributions in patients highlighted a lower prevalence of perseverative errors, with respect to other type of errors. Correlations between ACCT and other ET-based frontal-executive measures were significant and involved different frontal sub-domains. Limited correlations were observed between ACCT and standard ‘paper and pencil’ cognitive tests.

Conclusions

The newly developed ET-based measure of cognitive flexibility could be a useful tool to detect slight frontal impairments in non-demented ALS patients by bypassing verbal-motor limitations through the oculomotor-driven administration. The findings reported in the present study represent the first contribution towards the development of a full verbal-motor free executive test for ALS patients.

Use of neuropsychological tests for the diagnosis of dementia: a survey of Italian memory clinics

AIM

Providing an overview of the neuropsychological tests used in Italian memory clinics (defined as Centers for Cognitive Disorders and Dementias-CCDD in Italy) for the diagnosis of cognitive disorders and dementias.

METHODS

A total of 501 CCDD, out of all 536 active CCDD, were surveyed between February 2014 and August 2015 to verify the characteristics of the centres who performed a comprehensive neuropsychological assessment (NPA), defined as the administration of at least one test for verbal and visual episodic memory, attention, constructional praxis, verbal fluency and executive functions (minimum core tests-MCTs), as part of the diagnostic process.

RESULTS

A total of 45.7% of Italian CCDD performed a comprehensive MCT as part of the diagnostic process. The logistic regression model showed that the probability of including at least one psychologist in the team was higher in the CCDD that reported using a comprehensive NPA (OR 4.55; 95% CI 2.92 to 7.1), that CCDD in Southern Italy had a lower probability of using an MCT (OR 0.56; 95% CI 0.35 to 0.89) and that the use of an MCT was higher in university/Institute for Scientific Research and Healthcare CCDD (OR 10.97; 95% CI 3.85 to 31.25).

CONCLUSION

Almost half of the CCDD administered a set of MCTs; while the remaining centres only performed few tests or screening procedures. The neuropsychological tests used in Italian CCDD were comparable with those used in other European countries. Performing a comprehensive NPA remains the best way to assess and monitor cognitive deficits over time, thus further debate on the current status of NPAs in clinical practice is needed.

Structural and functional brain signatures of C9orf72 in motor neuron disease

This study investigated structural and functional magnetic resonance imaging abnormalities in hexanucleotide repeat expansion in chromosome 9 open reading frame 72 (C9orf72) motor neuron disease (MND) relative to disease severity-matched sporadic MND cases. We enrolled 19 C9orf72 and 67 disease severity-matched sporadic MND patients, and 22 controls. Sporadic cases were grouped in patients with: no cognitive/behavioral deficits (sporadic-motor); same patterns of cognitive/behavioral impairment as C9orf72 cases (sporadic-cognitive); shorter disease duration versus other sporadic groups (sporadic-early). C9orf72 patients showed cerebellar and thalamic atrophy versus all sporadic cases. All MND patients showed motor, frontal, and temporoparietal cortical thinning and motor and extramotor white matter damage versus controls, independent of genotype and presence of cognitive impairment. Compared with sporadic-early, C9orf72 patients revealed an occipital cortical thinning. C9orf72 patients had enhanced visual network functional connectivity versus sporadic-motor and sporadic-early cases. Structural cerebellar and thalamic damage and posterior cortical alterations are the brain magnetic resonance imaging signatures of C9orf72 MND. Frontotemporal cortical and widespread white matter involvement are likely to be an effect of the disease evolution rather than a C9orf72 marker.

An eye-tracker controlled cognitive battery: overcoming verbal-motor limitations in ALS

We assessed language, attention, executive, and social cognition abilities in a sample of patients with Amyotrophic Lateral Sclerosis (ALS) by means of a recently developed cognitive battery based on oculomotor control with eye-tracking (ET) technology. Twenty-one ALS patients and 21 age- and education-matched healthy subjects underwent the ET-based cognitive assessment, together with the standard cognitive screening tools [Frontal Assessment Battery (FAB); Montreal Cognitive Assessment (MoCA); and Digit Sequencing Task]. Psychological measures of anxiety (State-Trait Anxiety Inventory-Y) and depression (Beck Depression Inventory) were also collected, and an ET usability questionnaire was administered. For patients, clinical and respiratory examinations were also performed, together with behavioural assessment (Frontal Behavioural Inventory). The developed battery discriminated among patients and controls with regard to measures of verbal fluency, frontal abilities, and social cognition. Measures of diagnostic utility confirmed a higher diagnostic accuracy of such ET-based tests with respect to FAB; similar diagnostic accuracy emerged when comparing them to the other standard cognitive tools (MoCA, WM). Usability ratings about the ET tests were comparable among the two groups. The ET-based neuropsychological battery demonstrated good levels of diagnostic accuracy and usability in a clinical population of non-demented ALS patients, compared to matched healthy controls. Future studies will be aimed at further investigate validity and usability components by recruiting larger sample of patients, both in moderate-to-severe stages of the disease and affected by more severe cognitive impairment.

Spontaneous confabulations in amnestic-mild cognitive impairment due to Alzheimer's disease: a new (yet old) atypical variant?

Confabulation may be present in Alzheimer's disease (AD), but usually it is not a primary feature of either its typical or atypical variants. In this report, we describe the case of an AD patient who showed an unusual and enduring neuropsychiatric phenotype characterized by early and prominent spontaneous confabulation. Surprisingly, such atypical AD presentation bears a striking resemblance to presbyophrenia, a subtype of dementia which was described at the beginning of the twentieth century and then sank into oblivion. In discussion, we speculate on the "return" of presbyophrenia as an unrecognized neuropsychiatric variant of AD and its possible neuroanatomical substrates.

The validation of the Italian Edinburgh Cognitive and Behavioural ALS Screen (ECAS)

This study presents the Italian validation of the recently developed Edinburgh Cognitive and Behavioural ALS Screen (ECAS), a short screen for cognitive/behavioural alterations in patients with amyotrophic lateral sclerosis (ALS). We evaluated the psychometric properties of the ECAS Italian version in terms of reliability and convergent validity for both cognitive and behavioural features. Furthermore, we investigated the relationship with affective and clinical variables, in addition to ECAS usability and patients' insight into cognitive/behaviour changes. Finally, correlations between genetic and cognitive/behavioural data were analysed. We recruited 107 patients with ALS. Normative data were collected on 248 healthy subjects. Participants were administered the ECAS and two standard cognitive screening tools (FAB, MoCA), two psychological questionnaires (BDI, STAI/Y) and an ad hoc usability questionnaire. The FBI was also carried out with caregivers. Results showed that the ECAS Italian version discriminated well between patients and controls. The most prevalent deficit occurred in executive functions and fluency. Correlations were observed between the ECAS and standard cognitive screening tools and between the ECAS carer interview and the FBI, supporting its full convergent validity. In conclusion, the ECAS Italian version provides clinicians with a rapid, feasible and sensitive tool, useful to identify different profiles of cognitive-behavioural impairment in ALS.

Cognitive assessment in Amyotrophic Lateral Sclerosis by means of P300-Brain Computer Interface: a preliminary study

OBJECTIVE

To investigate the use of P300-based Brain Computer Interface (BCI) technology for the administration of motor-verbal free cognitive tests in Amyotrophic Lateral Sclerosis (ALS).

METHODS

We recruited 15 ALS patients and 15 age- and education-matched healthy subjects. All participants underwent a BCI-based neuropsychological assessment, together with two standard cognitive screening tools (FAB, MoCA), two psychological questionnaires (BDI, STAI-Y) and a usability questionnaire. For patients, clinical and respiratory examinations were also performed, together with a behavioural assessment (FBI).

RESULTS

Correlations were observed between standard cognitive and BCI-based neuropsychological assessment, mainly concerning execution times in the ALS group. Moreover, patients provided positive rates concerning the BCI perceived usability and subjective experience. Finally, execution times at the BCI-based neuropsychological assessment were useful to discriminate patients from controls, with patients achieving lower processing speed than controls regarding executive functions.

CONCLUSIONS

The developed motor-verbal free neuropsychological battery represents an innovative approach, that could provide relevant information for clinical practice and ethical issues. Its use for cognitive evaluation throughout the course of ALS, currently not available by means of standard assessment, must be addressed in further longitudinal validation studies. Further work will be aimed at refining the developed system and enlarging the cognitive spectrum investigated.

Brain MR Imaging in Patients with Lower Motor Neuron-Predominant Disease

Purpose To investigate the patterns of cortical thinning and white matter tract damage in patients with lower motor neuron (LMN)-predominant disease compared with healthy control subjects and those with classic amyotrophic lateral sclerosis (ALS) and to evaluate the relationship between brain structural changes and clinical and cognitive features in these patients. Materials and Methods This study was approved by the local ethical committee, and written informed consent was obtained from all subjects before enrollment. Twenty-eight patients with LMN-predominant disease were compared with 55 patients with ALS and 56 healthy control subjects. Patients underwent a clinical and neuropsychological assessment and T1-weighted and diffusion-tensor magnetic resonance (MR) imaging. Surface-based morphometry was used to assess cortical thickness. Tract-based spatial statistics and tractography were used to study white matter tract damage. Results Patients with LMN-predominant disease did not show differences compared with healthy control subjects in cortical thickness and diffusion-tensor MR imaging metrics. Patients with ALS showed cortical thinning of the motor-related cortices and a distributed involvement of the prefrontal, temporal, and parietal gyri (P < .05, false discovery rate corrected). Patients with ALS also showed white matter damage along motor and extramotor tracts compared with control subjects and patients with LMN-predominant disease (tract-based spatial statistics: P < .05, family-wise error corrected; tractography: P values < .001 to .05, false discovery rate corrected). In patients with LMN-predominant disease, cognitive deficits correlated with alterations in diffusivity in the left cingulum (r = -0.66, P = .01) and superior longitudinal fasciculus (r = -0.65, P = .05). Conclusion Motor and extramotor cortical thinning and diffusion-tensor MR imaging alterations were specific for motor neuron disease phenotypes, with clinically overt upper motor neuron involvement. However, the lack of significant differences in cortical thickness between subjects with LMN-predominant disease and those with ALS and cognitive deficits associated with alterations in diffusivity in patients with LMN-predominant disease suggest that investigating brain structural and microstructural MR imaging features may provide markers of central nervous system damage in patients with rare motor neuron disease. (©) RSNA, 2016 Online supplemental material is available for this article.