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International audience; Objective: Dysfunction of social cognition is well-recognized as one of amyotrophic lateral sclerosis (ALS) cognitive impairments. Previous studies have mostly associated social cognition subcomponents, including Theory of Mind (ToM), with executive dysfunction using highlydemanding tasks. In the present study, we investigate dysfunction of affective ToM in a sample of ALS patients without dementia and evaluate any possible associations both with executive and non-executive dysfunction. Methods: We included 42 ALS patients and 30 healthy controls (HC) and administered the Edinburgh Cognitive and Behavioural Amyotrophic Lateral Sclerosis Screen (ECAS). Affective ToM was examined based on the ECAS judgment of preference task; total score and type of errors ("favourite", "unclassified") were recorded for all participants. Results: A significant proportion of ALS patients (31%) were impaired on ToM task, scoring significantly lower compared to HC. Impairments in ToM task were more frequent (45%) in patients with cognitive impairment compared to those with intact cognition (15%). ALS patients showed significantly more errors on ToM task compared to HC. A significant association was found between ToM score and ECAS language and visuospatial abilities but not fluency, executive or memory function. Conclusion: Dysfunction of affective ToM appears prevalent in ALS patients without dementia, and associates with language and visuospatial abilities. These associations align with motor and extra-motor symptoms due to the degeneration across corresponding networks. Impaired ToM should be considered in clinical settings, since it might contribute to patients' social life, as well as the burden of their caregivers and relatives.

Pathological laughing and crying (PLC) is common in several neurological and psychiatric diseases and is associated with a distributed network involving the frontal cortex, the brainstem and cortico-pontine-cerebellar circuits. By applying multimodal neuroimaging approach, we examined the neuroanatomical substrate of PLC in a sample of patients with amyotrophic lateral sclerosis (ALS).We studied 56 non-demented ALS patients and 25 healthy controls (HC). PLC was measured in ALS using the Center of Neurologic Study Lability Scale (CNS-LS; cutoff score: 13). All participants underwent 3D-T1-weighted and 30-directional diffusion-weighted imaging at 3T. Voxel-based morphometry and tract-based spatial-statistics analysis was used to examine gray matter (GM) and white matter (WM) differences between ALS patients with and without PLC (ALS-PLC and ALS-nonPLC, respectively). Comparisons were restricted to regions with detected differences between ALS and HC, controlling for age, gender, total intracranial volume and depressive symptoms.In regions with significant differences between ALS and HC, ALS-PLC patients showed decreased GM volume in left orbitofrontal cortex, frontal operculum, and putamen and bilateral frontal poles, compared to ALS-nonPLC. They also had decreased fractional anisotropy in left cingulum bundle and posterior corona radiata. WM abnormalities were additionally detected in WM associative and ponto-cerebellar tracts (using a more liberal threshold).PLC in ALS is driven by both GM and WM abnormalities which highlight the role of circuits rather than isolated centers in the emergence of this condition. ALS is suggested as a useful natural experimental model to study PLC.

We examined the contribution of demographics and cognitive background variables (processing speed, visuospatial skill, working memory, and interference control) on derived Trail Making Test (TMT) scores in a large sample of Greek healthy participants. We included 775 participants and administered the TMT (TMT-A and TMT-B) and the Wechsler Intelligence Adult Scale (WAIS). Direct (TMT-A & TMT-B time-to-completion) and derived [difference TMT-(B - A) & ratio TMT-(B/A)] scores were calculated. Demographics (age, age(2), education, and gender) and WAIS Full Intelligence Quotient significantly predicted the direct TMT-A (R(2) = 0.426) and TMT-B (R(2) = 0.593) scores and to a lesser extent, the derived TMT-(B - A) (R(2) = 0.343) and TMT-(B/A) (R(2) = 0.088) scores. In a subsample of 537 healthy participants who also completed the Stroop Neuropsychological Screening Test (SNST), demographics (age and education), WAIS Digit Symbol, Block Design, Arithmetic, and SNST accounted for 44.8% and 59.7% of the variance on TMT-A and TMT-B, and 32.5% and 9.6% of the variance on TMT-(B - A) and TMT-(B/A), respectively. We found minimal influence of Block Design and Arithmetic on TMT-(B - A) and an absence of significant influence of any cognitive variable on TMT-(B/A) score. Concluding, derived TMT scores are suggested as indices to detect impairment in cognitive flexibility across the adult life span, since they minimize the effect of demographics and other cognitive background variables.