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BACKGROUND: This study is aimed at assessing the clinimetric properties and feasibility of the Italian version of the Montreal Cognitive Assessment (MoCA) in patients with Huntington's disease (HD). METHODS: N = 39 motor-manifest HD patients, N = 74 Parkinson's disease (PD) patients and N = 92 matched HCs were administered the MoCA. HD patients further underwent the Unified Huntington's Disease Rating Scale (UHDRS), self-report questionnaires for anxiety and depression and a battery of first- and second-level cognitive tests. Construct validity was tested against cognitive and behavioural/psychiatric measures, whereas ecological validity against motor-functional subscales of the UHDRS. Sensitivity to disease severity was tested, via a logistic regression, by exploring whether the MoCA discriminated between patients in Shoulson-Fahn stage ≤ 2 vs. > 2. The same analysis was employed to test its ability to discriminate HD patients from HCs and PD patients. RESULTS: The MoCA converged towards cognitive and behavioural measures but diverged from psychiatric ones, being also associated with motor/functional measures from the UHDRS. In identifying patients with cognitive impairment, adjusted MoCA scores were highly accurate (AUC = .92), yielding optimal diagnostics at the cut-off of < 19.945 (J = .78). The MoCA was able to discriminate patients in the middle-to-advanced from those in the early-to-middle stages of the disease (p = .037), as well as to differentiate HD patients from both HCs (p < .001) and PD patients (p < .001). CONCLUSIONS: The MoCA is a valid, diagnostically sound and feasible cognitive screener in motor-manifest HD patients, whose adoption is thus encouraged in clinical practice and research.
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Disfunción Cognitiva , Enfermedad de Huntington , Humanos , Enfermedad de Huntington/complicaciones , Enfermedad de Huntington/diagnóstico , Estudios de Factibilidad , Disfunción Cognitiva/etiología , Disfunción Cognitiva/complicaciones , Pruebas de Estado Mental y Demencia , Pruebas Neuropsicológicas , ItaliaRESUMEN
Huntington's disease (HD) is a genetic neurodegenerative disorder that affects not only the motor but also the cognitive and the neuropsychiatric domain. In particular, deficits in mental state recognition may emerge already at early pre-manifest stages of the disease. The aim of this research was to explore the relation between visual scanning behavior and complex mental state recognition in individuals with pre-manifest HD (preHD). Eighteen preHD and eighteen age- and gender-matched healthy controls took the revised "Reading the Mind in the Eyes" test while their eye-movements were tracked. In addition to the expected deficits in mental state recognition, preHD showed abnormalities concerning all three scanning variables we considered, namely the absolute number of fixations (FC), the average fixation duration (AFD), and the percentage of time spent fixating (FTR). In preHD, FC and FTR but not AFD predicted mental state recognition over and beyond general disease-related declines in cognition and motor functioning. Notably, preHD showed abnormal vertical and horizontal fixation patterns, and these patterns predicted mental state recognition, suggesting the involvement of mechanisms related to the embodied processing of emotional stimuli. Overall, our results suggest that impaired facial mental state recognition in pre-manifest HD is partly due to emotional-motivational factors affecting the visual scanning of facial expressions.
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Reconocimiento Facial , Enfermedad de Huntington , Emociones , Expresión Facial , Humanos , Enfermedad de Huntington/complicaciones , Pruebas Neuropsicológicas , Reconocimiento en PsicologíaRESUMEN
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.
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Esclerosis Amiotrófica Lateral , Trastornos del Conocimiento , Enfermedad de Huntington , Enfermedad de Parkinson , Esclerosis Amiotrófica Lateral/complicaciones , Esclerosis Amiotrófica Lateral/diagnóstico , Humanos , Enfermedad de Huntington/complicaciones , Enfermedad de Huntington/diagnóstico , Pruebas Neuropsicológicas , Enfermedad de Parkinson/complicaciones , Enfermedad de Parkinson/diagnóstico , Sensibilidad y EspecificidadRESUMEN
PURPOSE: We aimed to determine the origin and genetic characteristics of Huntington disease (HD) in the Middle East. METHODS: We performed genetic and genealogical analyses to establish the ancestral origin of the HTT pathgenic variant from a large kindred from Oman (hereafter called the OM-HD-01 pedigree) by single-nucleotide polymorphism and dense haplotype analysis genotyping. RESULTS: We traced the oldest ancestry of the largest, eight-generation, OM-HD-01 pedigree (n = 302 subjects, with 54 showing manifest HD) back to sub-Saharan Africa and identified a unique HD haplotype carried by all pedigree members, which consisted of portions of the C6 and C9 haplotypes and was carried by all affected members. Such a unique HD haplotype was of African origin and appeared to be associated with large CAG repeat expansions on average and high frequency of juvenile-onset HD. Three other families from the same area were also identified and found carrying a Caucasian HD haplotype A, also shared by most families of Arab ancestry. CONCLUSION: Mutated HTT spread into Middle East with a unique haplotype of African origin, appeared to be associated with juvenile-onset, a HD condition frequently occurring in Black Africans, and may have a significant impact on further development of novel targeted genetic therapies.
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Enfermedad de Huntington , Alelos , Haplotipos , Humanos , Proteína Huntingtina/genética , Enfermedad de Huntington/epidemiología , Enfermedad de Huntington/genética , Medio Oriente/epidemiología , Población BlancaRESUMEN
BACKGROUND: Cognitive abnormalities in Huntington's Disease (HD) can involve the specific impairment of the social perspective taking as well as difficulties in recognizing others' mental state many years before the onset of motor symptoms. AIMS: At the scope of assessing how the difficulties in mental state recognition might be an HD early sign before motor symptoms appear, our study was aimed to investigate how the recognition of others' mental states in HD subjects is moderated by different stimulus related features (gender, difficulty (low, medium, high), and valence (positive, negative, neutral) of the mental states that are to be recognized). METHODS: Subjects with premanifest (n = 20) and manifest (n = 40) HD performed the revised 'Reading the Mind in the Eyes Test' and were compared with age-matched healthy controls (HC, 40 subjects per cohort). RESULTS: Our results highlight an early impairment in mental state recognition preceding manifest HD symptoms and a deterioration of these abilities with HD progression. Moreover, we found in HD premanifest subjects an impairment concerning the recognition of negative and neutral mental states, as well as of mental states with moderate recognition difficulty. Finally, we found that participant gender did not influence the performance in recognizing others' mental states, while all participants recognized mental states displayed by females more accurately than those displayed by males. CONCLUSIONS: We conclude that difficulties in the recognition of complex mental states can be considered as an early sign of HD, before evident behavioral manifestations, and peculiar features of the stimulus influence it.
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Enfermedad de Huntington/psicología , Teoría de la Mente , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Enfermedad de Huntington/diagnóstico , Masculino , Persona de Mediana Edad , Pruebas Neuropsicológicas , Síntomas Prodrómicos , Factores Sexuales , Adulto JovenAsunto(s)
Enfermedad de Huntington/epidemiología , Adulto , Edad de Inicio , Femenino , Humanos , Proteína Huntingtina/genética , Enfermedad de Huntington/genética , Incidencia , Masculino , Persona de Mediana Edad , Omán/epidemiología , Linaje , Prevalencia , Expansión de Repetición de Trinucleótido , Adulto JovenRESUMEN
BACKGROUND: Cognitive changes in Huntington's disease (HD) precede motor manifestations. ENROLL-HD platform includes four cognitive measures of information processing speed (IPS). Our group is eager to seek clinical markers in the life stage that is as close as possible to the age of onset (ie, the so called prodromal HD phase) because this is the best time for therapeutic interventions. OBJECTIVES: Our study aimed to test whether cognitive scores in prodromal ENROLL-HD mutation carriers show the potential to predict the severity of motor and behavioral changes once HD became fully manifested. METHODS: From the global ENROLL-HD cohort of 21,343 participants, we first selected a premanifest Cohort#1 (ie, subjects with Total Motor Score (TMS) <10 and Diagnostic Confidence Level (DCL) <4, N = 1.222). From this cohort, we then focused on a prodromal Cohort#2 of subjects who were ascertained to phenoconvert into manifest HD at follow-up visits (ie, subjects from 6 ≤ TMS≤9 and DCL <4 to TMS≥10 and DCL = 4, n = 206). RESULTS: The main results of our study showed that low IPS before phenoconversion in Cohort#2 predicted the severity of motor and behavioral manifestations. By combining the four IPS cognitive measures (eg, the Categorical Verbal Fluency Test; Stroop Color Naming Test; Stroop Word Reading; Symbol Digit Modalities Test), we generated a Composite Cognition Score (CCS). The lower the CCS score the higher the TMS and the apathy scores in the same longitudinally followed-up patients after phenoconversion. CONCLUSIONS: CCS might represent a clinical instrument to predict the prognosis of mutation carriers who are close to manifesting HD.
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Enfermedad de Huntington , Humanos , Estudios Longitudinales , Estudios Retrospectivos , Pronóstico , Enfermedad de Huntington/diagnóstico , Progresión de la Enfermedad , CogniciónRESUMEN
(1) Background: Sleep patterns are frequently disrupted in neurodegenerative disorders such as Huntington disease (HD); however, they are still poorly understood, especially their association with clinic features. Our study aimed to explore potential correlations between sleep features and motor, cognitive, behavioural and functional changes in manifest HD subjects. (2) Methods: We enrolled 42 patients who were assessed by the Pittsburgh Sleep Quality Index (PSQI) and Insomnia Severity Index (ISI) questionnaires; clinical features were evaluated by the validated ENROLL-HD platform assay, including the Unified Huntington's Disease Rating Scale (UHDRS) and the Problem Behaviours Assessment Short Form (PBA-s). (3) Results: We found a significant association between the patients' perception of sleep abnormalities and scores of impaired independence, cognitive and motor performances. Specifically, sleep efficiency (PSQI-C4 subscores) and the use of sleep medications (PSQI-C6 subscores) seem to be more frequently associated with the severity of the disease progression. (4) Conclusion: sleep abnormalities represent an important part of the HD clinical profile and can impair patients' quality of life by affecting their level of independence, cognition performance and mental well-being.
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We focused on Cognitive Reserve (CR) in patients with early Huntington Disease (HD) and investigated whether clinical outcomes might be influenced by lifetime intellectual enrichment over time. CR was evaluated by means of the Cognitive Reserve Index questionnaire (CRIq), an internationally validated scale which includes three sections: education, working activity, and leisure time. The clinical HD variables were quantified at three different time points (baseline-t0, 1 year follow up-t1 and 2 years follow up-t2) as per the Unified Huntington's Disease Rating Scale (UHDRS), an internationally standardized and validated scale including motor, cognitive, functional and behavioral assays. Our sample consisted of 75 early manifest patients, withclinical stage scored according to the Total Functional Capacity (TFC) scale. Our correlational analysis highlighted a significant inverse association between CRIq leisure time (CRIq_LA) and longitudinal functional impairment (namely, the differential TFC score between t2 and t0 or ΔTFC) (p < 0.05), and the multidimensional progression of HD as measured by the composite UHDRS (cUHDRS, p < 0.01). CRIq_LA was significantly and positively associated with better cognitive performances at all time points (p < 0.05). Our results suggest that higher is the CRIq_LA, milder is the progression of HD in terms of functional, multidimensional and cognitive outcome.
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Background: This study aimed at assessing the diagnostic properties of the Frontal Assessment Battery (FAB) as to its capability to (1) discriminate healthy controls (HCs) from patients with Huntington's disease (HD) and (2) identify cognitive impairment in this population. Materials: Thirty-eight consecutive HD patients were compared to 73 HCs on the FAB. Patients further underwent the Montreal Cognitive Assessment (MoCA) and the Unified Huntington's Disease Rating Scale (UHDRS). Receiver-operating characteristics (ROC) analyses were run to assess both intrinsic-i.e., sensitivity (Se) and specificity (Sp), and post-test diagnostics, positive and negative predictive values (PPV; NPV) and likelihood ratios (LR+; LR-), of the FAB both in a case-control setting and to identify, within the patient cohort, cognitive impairment (operationalized as a below-cut-off MoCA score). In patients, its diagnostic accuracy was also compared to that of the cognitive section of the UHDRS (UHDRS-II). Results: The FAB and UHDRS-II were completed by 100 and 89.5% of patients, respectively. The FAB showed optimal case-control discrimination accuracy (AUC = 0.86-0.88) and diagnostic properties (Se = 0.68-0.74; Sp = 0.88-0.9; PPV = 0.74-0.8; NPV = 0.84-0.87; LR+ = 5.6-7.68; LR- = 0.36-0.29), performing even better (AUC = 0.9-0.91) at identifying cognitive impairment among patients (Se = 0.73-1; Sp = 0.86-0.71; PPV = 0.79-0.71; NPV = 0.82-1; LR+ =5.13-3.5; LR- = 0.31-0) and comparably to the UHDRS-II (89% vs. 85% of accuracy, respectively; p = 0.46). Discussion: In HD patients, the FAB is highly feasible for cognitive screening aims, being also featured by optimal intrinsic/post-test diagnostics within both case-control and case-finding settings.
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The "Spazio Huntington-A Place for Children" program was launched in 2019. The aim was to contact at risk kids within Huntington disease (HD) families, to provide counseling to their parents and to start a prospective follow-up of kids suspicious to manifest pediatric HD (PHD). We met 25 at risk kids in two years, four of whom with PHD and highly expanded (HE) mutations beyond 80 CAG repeats. We rated motor, neuropsychological and behavioral changes in all PHD kids by the Unified HD Rating Scale (UHDRS)-total motor score (TMS) and additional measures of (1) cognitive level (Leiter International Performance Scale), (2) adaptive functioning (Adaptive Behavior Assessment Systems), (3) receptive language (Peabody Picture Vocabulary Test) and (4) behavioral abnormalities (Child Behavior Check List and Children's Yale-Brown Obsessive Compulsive Scale). All PHD kids showed a severe progression of neurological and psychiatric manifestations including motor, cognitive and behavioral changes. The magnetic resonance imaging contributed to confirm the suspicious clinical observation by highlighting very initial striatum abnormalities in PHD. Spazio Huntington is a program to prospectively study PHD, the most atypical face of HD, and may represent the basis to recruit PHD patients in future clinical trials.
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Background: The semiology and determinants of apathy are largely unknown across amyotrophic lateral sclerosis (ALS), Parkinson's disease (PD), and Huntington's disease (HD), due to both motor and non-motor confounders. This study thus aimed at (1) profiling apathy in ALS, PD, and HD and (2) exploring its clinical determinants. Materials: Consecutive ALS (N = 99), PD (N = 73), and HD (N = 25) patients underwent a motor-free assessment of apathy (Dimensional Apathy Scale, DAS), global cognition, anxiety and depression. Function was assessed through disease-specific scales. The DAS was also completed by N = 101 healthy controls (HCs). Between-group comparisons on DAS scores were implemented by covarying for all applicable confounders. Predictive models on DAS scores were built through multiple, stepwise regressions. Results: Parkinson's disease and HD, but not ALS, patients were more apathetic than HCs-with HD patients also selectively showing lower initiation and poorer goal-directed planning than HCs. Higher apathetic features were detected in PD and HD as compared to ALS. Education was a protective factor against apathy in ALS. Anxiety was a risk factor for global apathy in ALS, HD, and to a lesser extent, in PD, whereas, protective only toward affective disintegration in PD and ALS. Cognitive inefficiency was a risk factor toward apathy in both PD and ALS. Depression was a risk factor for executive-related apathy in PD. Discussion: This study provides unprecedented insights into the heterogeneous semiology and determinants of apathy across ALS, PD, and HD via the DAS, in turn informing clinical practice and research.
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INTRODUCTION: Behavioral and cognitive changes can be observed across all Huntington disease (HD) stages. Our multicenter and retrospective study investigated the association between cognitive and behavioral scale scores in manifest HD, at three different yearly timepoints. METHODS: We analyzed cognitive and behavioral domains by the Unified Huntington's Disease Rating Scale (UHDRS) and by the Problem Behaviors Assessment Short Form (PBA-s), at three different yearly times of life (t0 or baseline, t1 after one year, t2 after two years), in 97 patients with manifest HD (mean age 48.62 ± 13.1), from three ENROLL-HD Centers. In order to test the disease progression, we also examined patients' motor and functional changes by the UHDRS, overtime. RESULTS: The severity of apathy and of perseveration/obsession was associated with the severity of the cognitive decline (p < .0001), regardless of the yearly timepoint. The score of irritability significantly and positively correlated with perseveration errors in the verbal fluency test at t0 (r = .34; p = .001), while the psychosis significantly and negatively correlated with the information processing speed at t0 (r = -.21; p = .038) and significantly and positively correlated with perseveration errors in the verbal fluency test at t1 (r = .35; p < .0001). The disease progression was confirmed by the significant worsening of the UHDRS-Total Motor Score (TMS) and of the UHDRS-Total Functional Capacity (TFC) scale score after two-year follow-up (p < .0001). CONCLUSION: Although the progression of abnormal behavioral manifestations cannot be predicted in HD, the severity of apathy and perseveration/obsessions are significantly associated with the severity of the cognitive function impairment, thus contributing, together, to the disease development and to patients' loss of independence, in addition to the neurological manifestations. This cognitive-behavior pattern determines a common underlying deficit depending on a dysexecutive syndrome.
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Enfermedad de Huntington , Problema de Conducta , Adulto , Cognición , Estudios Transversales , Humanos , Persona de Mediana Edad , Estudios Retrospectivos , Índice de Severidad de la EnfermedadRESUMEN
There has been great progress in Huntington's disease (HD) research. Yet, effective treatments to halt disease before the onset of disabling symptoms are still unavailable. Scientific breakthroughs require an active and lasting commitment from families. However, they are traditionally less involved and heard in studies. Accordingly, the European Huntington Association (EHA) surveyed individuals at risk (HDRisk) and with premanifest HD (PreHD) to determine which factors affect their willingness to participate in research. Questions assessed research experience and knowledge, information sources, reasons for involvement and noninvolvement, and factors preventing and facilitating participation. The survey included 525 individuals, of which 68.8% never participated in studies and 38.6% reported limited research knowledge. Furthermore, 52% trusted patient organizations to get research information. Reasons for involvement were altruistic and more important than reasons for noninvolvement, which were related to negative emotions. Obstacles included time/financial constraints and invasive procedures, while professional support was seen as a facilitator. PreHD individuals reported less obstacles to research participation than HDRisk individuals. Overall, a high motivation to participate in research was noted, despite limited experience and literacy. This motivation is influenced by subjective and objective factors and, importantly, by HD status. Patient organizations have a key role in fostering motivation through education and support.
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Huntington's disease (HD) is a genetic neurodegenerative disorder that affects not only the motor but also the cognitive domain. In particular, cognitive symptoms such as impaired executive skills and deficits in recognizing other individuals' mental state may emerge many years before the motor symptoms. This study was aimed at testing two cognitive hypotheses suggested by previous research with a new Stroop task created for the purpose: 1) the impairment of emotion recognition in HD is moderated by the emotions' valence, and 2) inhibitory control is impaired in HD. Forty manifest and 20 pre-manifest HD patients and their age- and gender-matched controls completed both the traditional "Stroop Color and Word Test" (SCWT) and the newly created "Stroop Emotion Recognition under Word Interference Task" (SERWIT), which consist in 120 photographs of sad, calm, or happy faces with either congruent or incongruent word interference. On the SERWIT, impaired emotion recognition in manifest HD was moderated by emotion type, with deficits being larger in recognizing sadness and calmness than in recognizing happiness, but it was not moderated by stimulus congruency. On the SCWT, six different interference scores yielded as many different patterns of group effects. Overall our results corroborate the hypothesis that impaired emotion recognition in HD is moderated by the emotions' valence, but do not provide evidence for the hypothesis that inhibitory control is impaired in HD. Further research is needed to learn more about the psychological mechanisms underlying the moderating effect of emotional valence on impaired emotion recognition in HD, and to corroborate the hypothesis that the inhibitory processes involved in Stroop tasks are not impaired in HD. Looking beyond this study, the SERWIT promises to make important contributions to disentangling the cognitive and the psychomotor aspects of neurological disorders. The research was approved by the Ethics Committee of the "Istituto Leonarda Vaccari", Rome on January 24, 2018.
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The psychopathological profile of patients with medication overuse headache (MOH) appears to be particularly complex. To better define it, we evaluated their performance on a targeted psychological profile assessment. We designed a case-control study comparing MOH patients and matched healthy controls (HC). Headache frequency, drug consumption, HIT-6, and MIDAS scores were recorded. All participants filled in the following questionnaires: Beck Depression Inventory-II Edition (BDI-2), trait subtest of State-Trait Anxiety Inventory (STAI-Y), Difficulties in Emotion Regulation Scale (DERS), Barratt Impulsiveness Scale (BIS-11), Toronto Alexithymia Scale (TAS-20). The primary endpoint was to establish if MOH patients have an altered psychopathological profile. The secondary endpoint was to establish whether the worst profile correlates with the worsening of headache and disability measures. We enrolled 48 consecutive MOH patients and 48 HC. MOH patients showed greater difficulty in recognition/regulation of emotions (DERS, TAS-20), depression (BDI-2), anxiety (STAI-Y), and impulsiveness (BIS-11). We found a positive correlation among DERS, BDI-2, STAI-Y, and BIS scores and MIDAS and HIT-6 scores and among DERS and headache frequency and drug consumption. MOH patients showed a high rate of emotion regulation difficulties, depression, and anxiety, which may negatively affect their headaches. The ability to regulate/recognize emotions may play a central role in sustaining medication overuse.
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BACKGROUND: People often make complicated decisions to help or to punish perfect strangers. Harming someone or breaking some moral imperative is usually linked to feeling guilt, and several researches suggested the existence of two different kinds of guilt: altruistic/empathic and deontological. AIM: Our study aimed to investigate the decision-making processes in moral and nonmoral judgments and assess how specific situations in which the subject is close to the victim or flanked by an authority can influence his decisions. METHODS: We used three different moral conditions: Empathic Moral (the decision has made while physically close to the potential victims), Deontological Moral (the decision has made while flanked by an "authority"), and Standard Moral (without any influence); a fourth condition is represented by Nonmoral dilemmas (the subject must make a choice between two different things and this does not cause any harm or victims). Previously, a pilot study was carried out for validating the experimental stories to be used in the main study. RESULTS: We observed a higher number of utilitarian/positive responses when individuals had to respond to Empathic Moral condition, with respect to Deontological Moral and Nonmoral dilemmas. Moreover, looking at the time needed to read the dilemma, under empathic guilt condition, people tended to be slower in reading the dilemmas than in other conditions and this both in case of positive and negative responses. No significant differences in time needed to effectively respond emerged. CONCLUSIONS: These findings suggested that be physically close to potential victims or be flanked by an "authority" differentially influence the decision-making processes in moral judgment, inducing slower decisions and more utilitarian answers, particularly in the scenario of physical proximity.
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Toma de Decisiones/fisiología , Empatía , Culpa , Juicio , Principios Morales , Adulto , Emociones/fisiología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
AIMS: To analyze brain functional connectivity in the somatomotor and default-mode networks (DMNs) of patients with Huntington disease (HD), its relationship with gray matter (GM) volume loss, and functional changes after pridopidine treatment. METHODS: Ten patients and ten untreated controls underwent T1-weighted imaging and resting-state functional magnetic resonance imaging (fMRI); four patients were also assessed after 3 months of pridopidine treatment (90 mg/d). The seed-based functional connectivity patterns from the posterior cingulate cortex and the supplementary motor area (SMA), considered cortical hubs of the DMN and somatomotor networks, respectively, were computed. FMRIB Software Library voxel-based morphometry measured GM volume. RESULTS: Patients had GM volume decrease in all cortical and subcortical areas of the somatomotor network with preservation of the SMA, and increased somatomotor and DMN connectivity. In DMN structures, functional connectivity impairment preceded volume loss. Pridopidine reduced the intensity of these aberrant connections. CONCLUSION: The abnormal connectivity of the somatomotor and DMN observed in HD patients may represent an early dysfunction marker, as it preceded volume loss in DMN. Pridopidine reduced connectivity of these networks in all four treated patients, suggesting that connectivity is sensitive to treatment response.