Exploring emotion regulation and emotion recognition in people with presymptomatic Huntington's disease: The role of emotional awareness

Theory of Mind in Huntington's Disease: A Systematic Review of 20 Years of Research

Background

People with Huntington's disease (HD) exhibit neurocognitive alterations throughout the disease, including deficits in social cognitive processes such as Theory of Mind (ToM).

Objective

The aim is to identify methodologies and ToM instruments employed in HD, alongside relevant findings, within the scientific literature of the past two decades.

Methods

We conducted a comprehensive search for relevant papers in the SCOPUS, PubMed, APA-PsyArticles, Web of Science, Redalyc, and SciELO databases. In the selection process, we specifically focused on studies that included individuals with a confirmed genetic status of HD and investigated ToM functioning in patients with and without motor symptoms. The systematic review followed the PRISMA protocol.

Results

A total of 27 papers were selected for this systematic review, covering the period from 2003 to 2023. The findings consistently indicate that ToM is globally affected in patients with manifest motor symptoms. In individuals without motor symptoms, impairments are focused on the affective dimensions of ToM.

Conclusions

Based on our analysis, affective ToM could be considered a potential biomarker for HD. Therefore, it is recommended that ToM assessment be included as part of neuropsychological evaluation protocols in clinical settings. Suchinclusion could aid in the identification of early stages of the disease and provide new opportunities for treatment, particularly with emerging drugs like antisense oligomers. The Prospero registration number for this review is CRD42020209769.

Social cognition in hyperkinetic movement disorders: a systematic review

Numerous lines of research indicate that our social brain involves a network of cortical and subcortical brain regions that are responsible for sensing and controlling body movements. However, it remains unclear whether movement disorders have a systematic impact on social cognition. To address this question, we conducted a systematic review examining the influence of hyperkinetic movement disorders (including Huntington disease, Tourette syndrome, dystonia, and essential tremor) on social cognition. Following the PRISMA guidelines and registering the protocol in the PROSPERO database (CRD42022327459), we analyzed 50 published studies focusing on theory of mind (ToM), social perception, and empathy. The results from these studies provide evidence of impairments in ToM and social perception in all hyperkinetic movement disorders, particularly during the recognition of negative emotions. Additionally, individuals with Huntington's Disease and Tourette syndrome exhibit empathy disorders. These findings support the functional role of subcortical structures (such as the basal ganglia and cerebellum), which are primarily responsible for movement disorders, in deficits related to social cognition.

A pilot evaluation of an 8-week mindfulness-based stress reduction program for people with pre-symptomatic Huntington's disease

People with Huntington's disease (HD) face difficult emotional and practical challenges throughout their illness, including in the pre-symptomatic stage. There are, however, extremely limited psychosocial interventions adapted to or researched for HD. We adapted and piloted an 8-week mindfulness-based stress reduction (MBSR) program in people with pre-symptomatic HD to determine if the program (i) was feasible and acceptable to participants, (ii) resulted in increased mindfulness understanding and skills, and (iii) led to improved psychological adjustment. Quantitative measures of mindfulness, emotion regulation, mood, and quality of life were administered pre and post the MBSR program and at 3-month follow-up. Measures of mindfulness practice and session clarity were administered weekly. Qualitative participant feedback was collected with a post-program interview conducted by independent clinicians. Seven participants completed the 8-week course. The program's feasibility and acceptability was supported by excellent retention and participation rates and acceptable rates of home practice completion. In addition, qualitative feedback indicated participant satisfaction with the program structure and content. Two core mindfulness skills (observing and non-judgment) showed significant improvement from pre- to post-assessment. Participant qualitative feedback indicated increased confidence and capacity to use mindfulness techniques, particularly in emotionally challenging situations. Participant questionnaire data showed good psychological adjustment at baseline, which did not change after treatment. Psychological benefits of the program identified in qualitative data included fewer ruminations about HD, reduced isolation and stigma, and being seen by others as calmer. These findings justify expansion of the program to determine its efficacy in a larger, controlled study.

Quality of life in the older adults: The protective role of self-efficacy in adequate coping in patients with chronic diseases

The purpose of the present study was to establish the association between self-efficacy, perception of disease, emotional regulation, and fatigue and the health-related quality of life in older adults living in the departments of Cesar and Atlántico in Colombia and who have been diagnosed with a chronic disease. The participants were 325 older adults of both sexes, with literacy and no presence of cognitive impairment in the Mini-Mental State Examination (MMSE); A non-probabilistic sampling was carried out. We used the MOS-SF-36 questionnaire, the Brief Illness Perception Questionnaire scale for measuring the perception of disease, the Stanford Patient Education Research Center’s Chronic Disease Self self-efficacy questionnaire for chronic patients, the Difficulties in Emotional Regulation Scale, and the Fatigue Severity Questionnaire as measurement instruments. The design was non-experimental cross-sectional with a correlational scope. The results indicate that self-efficacy, disease perception, emotional regulation and severity of fatigue are variables that could impact the physical function of quality of life, confirming that self-efficacy would work as a factor that decreases the probability that a participant score low on this dimension of quality of life. On the other hand, both the perception of the disease and the severity of fatigue were identified as factors that probably negatively influence quality of life.

Exploring and Deepening the Facets of Mentalizing: The Integration of Network and Factorial Analysis Approaches to Verify the Psychometric Properties of the Multidimensional Mentalizing Questionnaire (MMQ)

Mentalization is a complex and multifaceted trans-theoretical and trans-diagnostic construct that has found increasing application in the clinical context. This research aimed at deepening the psychometric properties of the Multidimensional Mentalizing Questionnaire (MMQ), a 33-item theoretically based self-report questionnaire allowing for a comprehensive assessment of mentalizing, by integrating factor analysis and network analysis approaches. A sample of 1640 participants (M_age = 33 years; SD = 13.28) was involved in the research. The six-factor structure was confirmed for the MMQ, and both the total and the subdimensions demonstrated good reliability. The network analysis has further enriched these results, showing the central role of the items attributable to Emotional Dysregulation or Reflexivity in influencing the network as well as the contribution of aspects related to Relational Discomfort in managing the flow of communication flow. Such findings may have useful clinical implications and emphasize the usefulness of the MMQ in both research and clinical practice.

Using a Clinical Formulation to Understand Psychological Distress in People Affected by Huntington’s Disease: A Descriptive, Evidence-Based Model

Huntington’s disease (HD) is an inherited, life-limiting neurodegenerative condition. People with HD experience changes in cognitive, motor and emotional functioning, and can also, mainly at later stages, exhibit behaviours that professionals and carers might find distressing such as hitting others, throwing objects, swearing or making inappropriate comments. While clinical formulation (an individualised approach used by mental health professionals to describe an individual’s difficulties) is a helpful tool to conceptualise patients’ wellbeing, a specific formulation framework has not yet been developed for HD. However, evidence has shown that formulation can help guide clinical interventions and increase consistency of approach across multi-disciplinary teams, refine risk management, and improve staff or carers’ empathic skills and understanding of complex presentations. As a consequence, this paper proposes a new clinical formulation model for understanding distress among people with HD, based on a biopsychosocial framework. More specifically, this includes key elements centring on an individual’s past experience and personal narratives, as well as anticipatory cognitions and emotions about the future. In-depth discussions regarding the components of the model and their importance in HD formulations are included, and a fictional yet representative case example is presented to illustrate their application within the context of personalised care.

More than Just a Brain Disorder: A Five-Point Manifesto for Psychological Care for People with Huntington’s Disease

Huntington’s disease (HD) is a rare and complex condition where affected individuals, family members, caregivers, and clinicians face a number of both long-term and fluctuating challenges. The predominant biomedical framework adopted in HD to date has traditionally viewed it as a brain disorder first and foremost. As a consequence, one of the most challenging aspects of the condition—psychological difficulties and their care—is often not given the emphasis it deserves in everyday clinical practice. Here, we propose a manifesto outlining five points to address the quality, effectiveness, availability, and accessibility of psychological care in HD. These include (1) Listening to People with HD, (2) Reformulating Difficulties Psychologically, (3) Exploring New Interventions, (4) Increasing Psychological Provision, and (5) Learning from Other Conditions. As the search for a cure continues, we hope that this manifesto will create a new impetus towards refining the current approach to psychological difficulties in HD and ultimately improve the quality of life of the tens of thousands of families affected by HD worldwide.

Cognitive and social cognition deficits in Huntington's disease differ between the prodromal and the manifest stages of the condition: A scoping review of recent evidence

OBJECTIVE

Huntington's disease (HD) is a dramatic neurodegenerative disorder encompassing severe motor symptoms coupled to significant cognitive and social cognition deficits. However, it is not clear whether and how patients' neuropsychological profile changes between the prodromal and the manifest stages of the condition. The aim of the present in-depth review is to consider cognitive and social cognition impairment in HD patients by differentiating deficits arising before diagnosis from those evident from the manifest phase onwards.

METHODS

Electronic databases were searched between January 1^st , 2010 and December 31^st , 2020 by using multiple combinations of keywords related to the investigation of neuropsychological profile in HD for preliminary search, and by defining strict selection criteria for studies to be included.

RESULTS

Forty-two studies were included. Evidence suggests that the neuropsychological profile in HD reflects a complex pathological spectrum of deficits. It includes impairment in the realms of executive functions, memory, attention, information processing, and social cognition. Interestingly, patients' profiles differ significantly between the manifest and the prodromal stages of their condition, not only in quantitative terms but also from a qualitative point of view.

CONCLUSIONS

Researchers and clinicians should thus include in clinical routine timely and specific neuropsychological assessments in order to monitor patients' cognitive status as time goes by, with the ultimate goal to implement effective clinical management strategies.

PRACTITIONER POINTS

The neuropsychological profile in HD encompasses a complex pathological spectrum of deficits. Patients' profiles differ significantly between the manifest and the prodromal stages of their condition. Clinicians should include in everyday practice a timely and specific neuropsychological assessment. Detecting patients' cognitive status during the early stages of the condition already can contribute significantly to implement effective clinical management strategies.

Problems with Social Cognition and Decision-Making in Huntington's Disease: Why Is it Important?

Huntington’s disease starts slowly and progresses over a 15–20 year period. Motor changes begin subtly, often going unnoticed by patients although they are typically visible to those close to them. At this point, it is the early non-motor problems of HD that arguably cause the most functional impairment. Approximately 65% of gene carriers will experience a reduction in their occupational level, and just under half will feel unable to manage their finances independently before a clinical diagnosis is made. Understanding what drives this impairment in activities of daily living is the key to helping people with HD to live more independently for longer, especially in early disease. Early cognitive decline is likely to play a contributory factor although few studies have looked directly at this relationship. Recently, it has been shown that along with the well documented dysexecutive syndrome seen in HD, changes in social cognition and decision-making are more common than previously thought. Furthermore, some of the early neuropathological and neurochemical changes seen in HD disrupt networks known to be involved in social functioning. In this review, we explore how HD changes the way individuals interact in a social world. Specifically, we summarise the literature on both classical and social decision-making (value-based decision-making in a social context) along with studies of theory of mind, empathy, alexithymia, and emotion recognition in HD. The literature specific to HD is discussed and supported by evidence from similar neurodegenerative disorders and healthy individuals to propose future directions and potential therapeutic avenues to be explored.

Experiences of Mindfulness-Based Cognitive Therapy for Premanifest Huntington's Disease

BACKGROUND

Psychological difficulties such as anxiety, depression, and irritability are common in Huntington's disease, even for premanifest individuals. However, very little evidence exists of psychological approaches to manage this distress. We have conducted a feasibility study with an embedded qualitative component to investigate the possibility of using mindfulness-based cognitive therapy (MBCT) and present here the findings from the qualitative data.

OBJECTIVE

To investigate the experience of premanifest individuals learning and practising mindfulness through completing a course of MBCT.

METHODS

Twelve premanifest individuals completed a course of MBCT and attended three follow up reunion meetings over the following year. Eleven participants agreed to be interviewed post-course and ten participants one year post-course about their experience of the course and any impact on their lives. Seven participants nominated a friend or relative (supporter) to be involved in the research, of whom six agreed to be interviewed post-course and two at one year about the impact of the course on the participants. Data were analysed using reflexive thematic analysis.

RESULTS

Four themes were constructed from the data: 1) A meeting of minds: the group facilitating learning and support; 2) Mindfulness is hard, but enables more effective emotional management; 3) Mindfulness can change the relationship with self and others; and 4) Benefiting from mindfulness: the importance of persistence.

CONCLUSION

The participants who completed the course found it beneficial. Some participants reported reductions in psychological distress, a greater sense of calm and better emotion regulation, with some of these positive changes also noticed by supporters. MBCT is worthy of further investigation for this population.

Psychopathological Comorbidities and Clinical Variables in Patients With Medication Overuse Headache

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.

New Perspectives on Emotional Processing in People with Symptomatic Huntington's Disease: Impaired Emotion Regulation and Recognition of Emotional Body Language†

OBJECTIVE

Emotion regulation and emotional body language (EBL) recognition represent two fundamental components of emotional processing that have recently seen a considerable surge in research interest, in part due to the role they play in optimizing mental health. This appears to be particularly true for clinical conditions that can profoundly affect emotional functioning. Among these is Huntington's disease (HD), a neurodegenerative disorder that is associated with several psychological difficulties and cognitive impairments, including well-established deficits in facial emotion recognition. However, although the theoretical case for impairments is strong, the current evidence in HD on other components such as emotion regulation and EBL recognition is sparse.

METHOD

In this study, it was hypothesized that emotion regulation and recognition of EBL are impaired in people with symptomatic HD, and that these impairments significantly and positively correlate with each other. A between-subjects design was adopted to compare 13 people with symptomatic HD with 12 non-affected controls matched for age and education.

RESULTS

The results showed that emotion regulation and EBL recognition were significantly impaired in individuals with HD. Moreover, a significant positive correlation was observed between facial and EBL recognition impairments, whereas EBL performance was negatively related to the disease stage. However, emotion regulation and recognition performances were not significantly correlated.

CONCLUSIONS

This investigation represents the first evidence of a deficit of emotion regulation and EBL recognition in individuals with HD. The clinical implications of these findings are explored, and indications for future research are proposed.

Psychological Interventions for People with Huntington's Disease: A Call to Arms

BACKGROUND

Although Huntington's disease (HD) can cause a wide range of psychological difficulties, no review has ever been carried out on the range of psychological interventions adopted with this population.

OBJECTIVE

To scope the literature on psychological interventions for psychological difficulties in people affected by HD.

METHODS

A systematic scoping review was performed across MEDLINE, PsycINFO, CINAHL, Academic Search Ultimate, and Cochrane Library up to 1 March 2020.

RESULTS

From an initial return of 1579 citations, a total of nine papers were considered eligible for review. These included a qualitative investigation, three case studies, two case series, two uncontrolled pretest-posttest designs, and only one randomised control trial (RCT). Despite the wide range of psychological difficulties which can be experienced by people affected by the HD gene expansion, the adopted interventions only accounted for five main psychological outcomes (anxiety, apathy, depression, irritability, and coping). Further discussion and suggestions for future research are provided for each outcome.

CONCLUSION

The current literature on psychological interventions in people affected by HD is extremely limited both in terms of methods and addressed clinical outcomes. Consequently, no conclusions can be offered yet as to which psychological therapy may help this population. As further more comprehensive research is urgently needed for this group, the ultimate aim of the present review is to act as a call to arms for HD researchers worldwide to help shed light on the most effective way to translate psychological theory into practice for the benefit of people affected by HD.

Deep Learning Classification of Neuro-Emotional Phase Domain Complexity Levels Induced by Affective Video Film Clips

In the present article, a novel emotional complexity marker is proposed for classification of discrete emotions induced by affective video film clips. Principal Component Analysis (PCA) is applied to full-band specific phase space trajectory matrix (PSTM) extracted from short emotional EEG segment of 6 s, then the first principal component is used to measure the level of local neuronal complexity. As well, Phase Locking Value (PLV) between right and left hemispheres is estimated for in order to observe the superiority of local neuronal complexity estimation to regional neuro-cortical connectivity measurements in clustering nine discrete emotions (fear, anger, happiness, sadness, amusement, surprise, excitement, calmness, disgust) by using Long-Short-Term-Memory Networks as deep learning applications. In tests, two groups (healthy females and males aged between 22 and 33 years old) are classified with the accuracy levels of [Formula: see text] and [Formula: see text] through the proposed emotional complexity markers and and connectivity levels in terms of PLV in amusement. The groups are found to be statistically different ( p << 0.5) in amusement with respect to both metrics, even if gender difference does not lead to different neuro-cortical functions in any of the other discrete emotional states. The high deep learning classification accuracy of [Formula: see text] is commonly obtained for discrimination of positive emotions from negative emotions through the proposed new complexity markers. Besides, considerable useful classification performance is obtained in discriminating mixed emotions from each other through full-band connectivity features. The results reveal that emotion formation is mostly influenced by individual experiences rather than gender. In detail, local neuronal complexity is mostly sensitive to the affective valance rating, while regional neuro-cortical connectivity levels are mostly sensitive to the affective arousal ratings.

Health care professionals' views on psychological factors affecting nutritional behaviour in people with motor neuron disease: A thematic analysis

Motor neuron disease (MND), also known as amyotrophic lateral sclerosis, is a neurodegenerative disorder that causes progressive muscle paralysis and typically leads to death within 3 years. As no cure is currently available, symptomatic management is the mainstay of treatment. An important part of this is optimizing nutritional intake with evidence that this may positively affect survival and quality of life. Health care professionals (HCPs) play a pivotal role in nutritional management of people with MND (pwMND) but, to date, their views on the psychological barriers faced by pwMND have not been explored. Such an exploration may identify ways in which the delivery of nutritional care for pwMND can be optimized.

METHODS

Five qualitative focus groups were carried out across the United Kingdom in June 2018 with 51 participants, including 47 HCPs involved with MND care and four service user representatives. Data were analysed through thematic analysis.

RESULTS

Four overarching themes were identified: psychological adjustment and patient engagement; nutrition and the need for control; knowledge of nutrition and the complexity of MND; and the psychosocial nature of eating.

CONCLUSIONS

The findings suggest that the nutritional management of pwMND should be mindful of factors such as the impact of distress at the time of diagnosis, the availability of clear information on nutrition and MND, as well as the importance of illness perceptions and coping strategies. Moreover, tailored psychological interventions should be considered to mitigate the impact on MND on the experience of eating. Statement of contribution What is already known on this subject? Since weight loss and reduced body mass index (BMI) have been identified as independent risk factors for prognosis and survival in motor neuron disease (MND), nutritional management represents an important component of the symptomatic care of people with MND (pwMND) aimed at prolonging survival and maintaining or improving quality of life. However, the current guidelines and quantitative and qualitative literature on the topic are mainly focused on issues around enteral feeding and gastrostomy insertion, and very little is currently known about potential psychological enablers or barriers to earlier nutritional management, especially from the perspectives of health care professionals (HCPs) involved in the delivery of nutritional care in pwMND. What does this study add? First qualitative investigation of enablers or barriers to nutritional care in pwMND from the perspective of HCPs. New insight into psychological factors (e.g., adjustment, avoidance, loss of control) in nutritional care for pwMND. Practical implications and novel clinical suggestions for HCPs involved in nutritional care of pwMND.

Validity of irritability in Huntington's disease: A scoping review

PURPOSE

To scope the literature concerning irritability in Huntington's disease to determine whether or not irritability is a valid and meaningful construct within this population.

METHOD

A scoping literature review was conducted based on findings from a search of five databases (Academic Search Ultimate, PsycINFO, CINAHL, Scopus and Web of Science) in November 2018. From an initial return of 453 papers, 40 were found suitable for review.

RESULTS

Review of the 40 studies highlighted several aspects of irritability in people with HD which influence its validity as an independent construct in context of the disease. While various measures are used to assess irritability, a gold standard has yet to be identified and consequently irritability is assessed inconsistently across the literature. In addition, the results suggest that irritability may not reflect pathological disease processes in HD, but rather comprises a multidimensional construct which appears to be strongly associated with other psychological difficulties such as depression and anxiety.

CONCLUSIONS

The current concept of irritability in people with HD continues to lack a general consensus in the clinical literature, in terms of both operationalisation and assessment. Consequently, further research is warranted in order to determine the extent to which irritability is a valid construct within the context of HD, including its associated behavioural, cognitive and affective dimensions.

Adult-onset Huntington disease: An update

Appropriate nursing-care strategies depend on the early recognition of Huntington disease (HD) to prioritize a plan of care. This article offers perspective on the clinical presentation, prognosis, diagnosis, and management of adult-onset HD.

Beyond diagnosis: Mentalization and mental health from a transdiagnostic point of view in adolescents from non-clinical population

An increasing volume of evidence suggests that mentalization (MZ) can be an important factor in the transition from mental health to mental illness and vice versa. However, most studies are focused on the role of MZ in specific disorders. This study aims to evaluate the relationship between MZ and mental health as a trans-diagnostic process. A sample of 172 adolescents aged 12 to 18 years old (M = 14.6, SD = 1.7; 56.4% of girls) was assessed on measures of MZ, psychopathology and psychological functioning from a multimethod and multi-informant perspective. Contrary to predictions, MZ was not associated with general psychopathology and comorbidity, even when explored from a broad, trans-diagnostic perspective. However, we observed a robust association linking MZ to functioning and well-being across many dimensions, involving social, role and several psychological indicators of adjustment and mental health. These results suggest that MZ may contribute to mental health beyond symptoms, not so much associated with psychopathology, but rather resilience and well-being.

Effects of stimulus-related variables on mental states recognition in Huntington's disease

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.

Task-switching abilities in pre-manifest Huntington's disease subjects

INTRODUCTION

Huntington's Disease (HD) cognitive dysfunction occurs before unequivocal motor signs become apparent. The predominant early cognitive abnormal domains may include deficits in psychomotor speed, negative emotion recognition and executive functioning. Our study is aimed to investigate the executive control of cognition in pre-manifest (pre) HD subjects, by means of a task-switching protocol.

METHODS

We recruited 30 pre-HD subjects and 18 age-, sex- and education-matched Healthy Controls (HC). Subjects were assigned to two experimental groups: 15 pre-HD1 with a Total Motor Score (TMS) ≤4 (far from onset) and 15 pre-HD2 with a 5 ≤ TMS≤9 (near to onset and Diagnostic Confidence Level (DCL) still<4). Two different tasks were performed in rapid and random succession, so that the task was either changed from one trial to the next one (switch trials) or repeated (repetition trials). Switch trials are usually slower than repetitions, causing a so-called Switch Cost (SC).

RESULTS

Pre-HD subjects had worse performance than HC in the switch and repetition trials, as indicated by increased SC and reaction times. In particular, pre-HD2 showed impaired switching abilities with reaction times slower than pre-HD1 and HC.

CONCLUSIONS

Our study highlighted a task-switching impairment since HD was still at a pre-manifest stage. Such abnormalities worsen when pre-HD subjects start to show subtle motor manifestations, still nonspecific and insufficient to define the clinical diagnosis of HD (DCL<4). Considering that such abilities have obvious implications for activities of daily living, early cognitive rehabilitation programs addressing such deficits might be useful in the premanifest stage of the disease.