Social cognition in cervical dystonia: A case-control study

Moving on with (social) cognition in idiopathic cervical dystonia

OBJECTIVE

Cervical dystonia (CD) is a movement disorder characterized by involuntary muscle contractions causing sustained twisting movements and abnormal postures of the neck and head. Assumed affected neuronal regions are the cortico-striatal-thalamo-cortical circuits, which are also involved in cognitive functioning. Indeed, impairments in different cognitive domains have been found in CD patients. However, to date studies have only investigated a limited range of cognitive functions within the same sample. In particular, social cognition (SC) is often missing from study designs. Hence, we aimed to evaluate a broad range of cognitive functions including SC in CD patients.

METHOD

In the present study 20 idiopathic CD patients and 40 age-, gender-, and IQ-matched healthy controls (HCs) were assessed with tests for non-SC (verbal memory, psychomotor speed, and executive functions) as well as for SC (emotion recognition, Theory of Mind (ToM), and empathy).

RESULTS

CD patients scored on average significantly lower than HC on tests for non-SC, but did not show impairments on any of the tests for SC.

CONCLUSIONS

The current study showed impairments in non-SC in CD, but intact social cognitive functions. These results underline the importance of recognizing non-motor symptoms in idiopathic CD patients, but emphasize a focus on identifying strengths and weaknesses in cognitive functioning as these influence daily life activities.

Are Cognitive Symptoms Part of the Phenotypic Spectrum of Idiopathic Adult-Onset Dystonia? Summary of Evidence from Controlled Studies

BACKGROUND

Cognitive dysfunction has been reported in idiopathic adult-onset dystonia (IAOD), but whether this is a primary or secondary component of the disorder remains uncertain.

OBJECTIVE

Here, we aimed to analyze the key domains of abnormal cognitive performance in IAOD and whether this is associated with motor or mood changes.

METHODS

Article selection for our critical review was guided by PRISMA guidelines (mesh terms "dystonia" and "cognitive," publication period: 2000-2022). Only peer-reviewed, English-language original case-control studies involving patients with IAOD who were not exposed to dopamine- or acetylcholine-modulating agents and validated cognitive assessments were included.

RESULTS

Abstract screening ultimately yielded 22 articles for full-text review and data extraction. A greater proportion of studies (17 of 22, 82%) reported abnormal cognitive performance in IAOD. Most of these studies focused on blepharospasm (BSP) and cervical dystonia (10 and 14, respectively). Most studies reporting cognitive impairment (11 of 17) identified multidomain impairment in cognition. Executive functions were the domain most frequently explored (14 of 22 studies), 79% of which detected worse performance in people with dystonia. Results related to other domains were inconclusive. Cognitive abnormalities were independent of motor symptoms in most studies (7 of 12) that explored this relationship and independent of mood status in all 8 that investigated this.

CONCLUSIONS

Within IAOD, cognitive dysfunction (in particular, executive dysfunction) has been documented mainly in BSP and cervical dystonia. More comprehensive testing is warranted to assess abnormalities in other domains and in other forms of IAOD, as well as to evaluate longitudinal progression of cognitive disturbances in this condition.

A Systematic Review of Cognition in Cervical Dystonia

Growing evidence points to a spectrum of non-motor symptoms, including cognitive difficulties that have a greater impact on functional outcomes and quality of life than motor symptoms in cervical dystonia (CD). Some cognitive impairments have been reported; however, findings are inconsistent, and described across mixed groups of dystonia. The current review aimed to examine the evidence for cognitive impairments in CD. MEDLINE, EMBASE, PsychINFO and Web of Science databases were searched. Studies were included if they met the following criteria (i) cross-sectional or longitudinal studies of adults with CD, (ii) where the results of standardised measures of cognitive or neuropsychological function in any form were assessed and reported, (iii) results compared to a control group or normative data, and (iv) were published in English. Results are presented in a narrative synthesis. Twenty studies were included. Subtle difficulties with general intellectual functioning, processing speed, verbal memory, visual memory, visuospatial function, executive function, and social cognition were identified while language, and attention and working memory appear to be relatively spared. Several methodological limitations were identified that should be considered when interpreting the evidence to describe a specific profile of cognitive impairment in CD. Clinical and research implications are discussed.

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 comprehensive cognitive analysis of cervical dystonia: A single centre study

Introduction

Cervical dystonia (CD) presents as a motor disorder but has a number of non-motor features. Studies have demonstrated diverse changes in cognition in patients with CD. The rarity of this disorder, phenotypic heterogeneity, and, in particular, a lack of consistency in cognitive testing measures limits clear definition of cognitive changes in this disorder. The relationship between cognition, motor symptoms and quality of life has not been well defined. We undertook a comprehensive analysis of cognition in CD.

Methods

Patients with adult onset idiopathic isolated CD (AOICD) who had completed a battery of cognitive assessments- general intellectual functioning, verbal and visual memory, executive functions and social cognition measures, were included. Participants were assessed for mood symptoms, motor severity and quality of life.

Results

13 patients (8 women) with AOICD were included covering 40 cognitive subtests. Mean age was 59.9 years and mean TWSTRS-2 severity was 11. Mean estimated premorbid function was in the normal range. Overall performance on most measures were within normal limits. The lowest mean z-score was observed in Florida Affect Battery (social cognition) subtests, z = -1.75 and -0.81. and in verbal recall, z = -0.82. The majority of patients (75%) scored below population mean on spatial working memory and (62%) performed below population mean on word retrieval and working memory.

Conclusion

We provide detailed cognitive results across a wide range of measures. Although patients tended towards average outcomes on the majority of tests, poorer performance than expected averages were noted in measures of social cognition, word retrieval, spatial working memory and, processing speed.

Social cognition in cervical dystonia

Background

Whilst traditionally considered a movement disorder, it is now generally accepted that cervical dystonia (CD) presents with additional non-motor symptoms which significantly impact quality of life. Our study primarily aimed to explore social cognition and levels of psychological distress in individuals with CD, in comparison to age- and sex-matched healthy controls.

Methods

20 participants with CD attending a specialist movement disorders clinic were recruited. 20 age and sex matched neurologically healthy controls were recruited in parallel. Participants completed the Hospital Anxiety and Depression Scale, and two novel social cognition tasks: The Cambridge Mindreading Face-Voice Battery (CAFMB) and the Edinburgh Social Cognition Test (ESCoT).

Results

Participants with CD exhibited poorer complex emotion recognition abilities for visual and auditory stimuli, compared to controls on the CAFMB task. Participants with CD did not differ significantly from controls on performance on cognitive or affective Theory of Mind tasks, or interpersonal or intrapersonal understanding of social norms, as measured by the ESCoT. The proportion of depressive symptoms was significantly higher for participants with CD than controls. 40% of participants with CD reported clinically elevated depressive symptoms, and 60% reported clinically elevated anxiety. Poorer understanding of emotional facial expressions was associated with higher levels of depression in the CD group.

Conclusions

Significant between-group differences between participants with CD and controls suggests socio-cognitive dysfunction is an important aspect of the non-motor syndrome of CD. Findings highlight the need for assessment of and intervention for both social cognitive difficulties and psychological distress in individuals with CD.

The mind and the hand

Symptoms are determined in large part by mindsets. Feelings of distress and unhelpful thoughts (misinterpretations) of symptoms account for much of the variability in comfort and capability with the severity of the underlying pathophysiology making a more limited contribution. Incorporating this experimental evidence into the daily practice of hand surgery will help us find ways to develop healthy mindsets, to prioritize the alleviation of distress and the gentle redirection of unhelpful thoughts, to avoid unnecessary surgery, and to provide better psychological and social support for people recovering from injury and surgery.

The Collicular-Pulvinar-Amygdala Axis and Adult-Onset Idiopathic Focal Dystonias

Adult-onset idiopathic focal dystonias (AOIFD) are the most common type of dystonia. It has varied expression including multiple motor (depending on body part affected) and non-motor symptoms (psychiatric, cognitive and sensory). The motor symptoms are usually the main reason for presentation and are most often treated with botulinum toxin. However, non-motor symptoms are the main predictors of quality of life and should be addressed appropriately, as well as treating the motor disorder. Rather than considering AOIFD as a movement disorder, a syndromic approach should be taken, one that accommodates all the symptoms. Dysfunction of the collicular-pulvinar-amygdala axis, with the superior colliculus as a central node, can explain the diverse expression of this syndrome.

Cognitive and Neuropsychiatric Impairment in Dystonia

PURPOSE OF REVIEW

To review recent literature evaluating psychiatric and cognitive symptoms in dystonia, the two non-motor symptom groups most frequently evaluated in dystonia research and recognised in clinical practice.

RECENT FINDINGS

Recent work has embedded clinical recognition of psychiatric symptoms in dystonia, with depressive and anxiety-related symptoms routinely observed to be the most common. Less explored symptoms, such as self-harm, suicidal ideation, and substance abuse, represent newer areas of investigation, with initial work suggesting higher rates than the background population. Investigation of cognitive function has provided less consistent results, both within individual dystonia subtypes and across the spectrum of dystonias, partly reflecting the heterogeneity in approaches to assessment. However, recent work indicates impairments of higher cognitive function, e.g. social cognition, and disrupted visual and auditory sensory processing. Dystonia demonstrates psychiatric and cognitive symptom heterogeneity, with further work needed to recognise endophenotypes and improve diagnostic accuracy, symptom recognition, and management.

Attention impairment in patients with cervical dystonia: An attention network test study

Objective

The purpose of this study was to investigate attentional network functional characteristics in patients with cervical dystonia (CD).

Methods

A total of 29 patients with CD and 26 healthy controls (HCs) were recruited. All subjects participated in the study and underwent the Attention Network Test (ANT), which evaluated the efficiencies of three independent attention networks (alerting, orienting, and executive control), as well as reaction time (RT) and accuracy.

Results

Significant differences between CD patients (9.86 ± 27.95 ms) and HCs (33.62 ± 23.41 ms) were observed in the alerting network (t = −3.40, p < 0.05). In contrast, the orienting network (t = 0.26, p = 0.79), executive control network (Z = −0.55, p = 0.58), total mean reaction time (t = −2.6, p = 0.79), and total accuracy rate (Z = −1.67, p = 0.09) showed no significant differences between the two groups.

Conclusion

Patients with CD showed a significant deficit in the alerting network. However, they did not show any deficits in the orienting or executive control network. In addition, the alerting, orienting, and executive control network functions of CD patients were all affected by the severity of torticollis, especially the alerting network function.

Reliability of DNMSQuest as a Screening Tool for Mood Disorders in Cervical Dystonia

Background

The high prevalence of mood disorders in cervical dystonia, often unaddressed in botulinum toxin clinics, is a major factor in impaired quality of life. There is a clear need for a brief screening method for identifying these disorders; the Dystonia non-motor symptoms questionnaire (DNMSQuest) has been proposed as such.

Objective

We aimed to assess the practical utility of the DNMSQuest and compare it with validated rating scales for anxiety, depression and quality of life.

Methods

In 88 patients with cervical dystonia, we compared results from the DNMSQuest with mood rating scales [Beck Anxiety Inventory (BAI), Beck Depression Index (BDI-II) and Hospital Anxiety and Depression Scale (HADS)], quality of life measures [European Quality of Life (EQOL) and European Quality of Life Visual Analogue Scale (EQOLVAS)] and with assessments of dystonia severity [Cervical Dystonia Impact Profile-58 (CDIP58) and Toronto Western Rating Scale for Spasmodic Torticollis (TWSTRS)].

Results

Using a cut off score on the DNMSQuest of 5, we noted that DNMSQuest had a sensitivity of 85% for detecting anxiety and depression using the BAI and BDI-II, and 76% and 78% for anxiety and depression respectively using the HADS. The DNMSQuest correlated strongly with BAI (ρ = 0.715), BDI-II (ρ = 0.658), HADS-Anxiety (ρ = 0.616), HADS-Depression (ρ = 0.706), EQOL (ρ = 0.653) and CDIP-58 (ρ = 0.665).

Conclusion

The DNMSQuest is a brief, sensitive and non-specific instrument for identifying patients that warrant further review for anxiety and depression and can easily be implemented in a neurologist-run botulinum toxin clinic.

Dystonia Management: What to Expect From the Future? The Perspectives of Patients and Clinicians Within DystoniaNet Europe

Improved care for people with dystonia presents a number of challenges. Major gaps in knowledge exist with regard to how to optimize the diagnostic process, how to leverage discoveries in pathophysiology into biomarkers, and how to develop an evidence base for current and novel treatments. These challenges are made greater by the realization of the wide spectrum of symptoms and difficulties faced by people with dystonia, which go well-beyond motor symptoms. A network of clinicians, scientists, and patients could provide resources to facilitate information exchange at different levels, share mutual experiences, and support each other's innovative projects. In the past, collaborative initiatives have been launched, including the American Dystonia Coalition, the European Cooperation in Science and Technology (COST-which however only existed for a limited time), and the Dutch DystonieNet project. The European Reference Network on Rare Neurological Diseases includes dystonia among other rare conditions affecting the central nervous system in a dedicated stream. Currently, we aim to broaden the scope of these initiatives to a comprehensive European level by further expanding the DystoniaNet network, in close collaboration with the ERN-RND. In line with the ERN-RND, the mission of DystoniaNet Europe is to improve care and quality of life for people with dystonia by, among other endeavors, facilitating access to specialized care, overcoming the disparity in education of medical professionals, and serving as a solid platform to foster international clinical and research collaborations. In this review, both professionals within the dystonia field and patients and caregivers representing Dystonia Europe highlight important unsolved issues and promising new strategies and the role that a European network can play in activating them.

Adult onset dystonia: A disorder of the collicular-pulvinar-amygdala network

Models attempting to explain the pathogenesis of adult onset idiopathic focal dystonia often fail to accommodate the entire spectrum of this disorder: the diverse motor and non-motor symptoms, psychiatric and cognitive dysfunction, as well as the sub-clinical, physiological and anatomical, abnormalities. We propose, and present the accumulating evidence, that the adult onset dystonia syndrome is due to disruption in the covert-attentional network, the unconscious sub-cortical mechanism for the detection of potentially environmentally threatening (salient) stimuli, involving the collicular-pulvinar-amygdala network. A critical consideration of this network indicates a number of hypothesis-generated research questions aimed at elucidating the pathogenesis of adult onset dystonia. Given the rarity of adult onset dystonia, international, multidisciplinary, multicentre studies are required to elucidate the prevalence of non-motor symptoms in unaffected relatives, in particular, using temporal discrimination. Research focussing on the non-motor symptoms and the collicular-pulvinar-amygdala pathway may be the key to understanding adult-onset idiopathic focal dystonias (AOIFD) pathophysiology.

Non-motor features of cervical dystonia: Cognition, social cognition, psychological distress and quality of life

INTRODUCTION

Non-motor features of cervical dystonia (CD) have been identified, including depression, anxiety, and neuropsychological deficits. The aims were: to provide a clinical neuropsychological profile of CD patients with specific focus on social cognition; assess levels of psychological distress; and investigate the relationship between non-motor features of CD, including cognitive functioning, psychological distress, CD severity, pain, and health-related quality of life (HR-QoL).

METHODS

A multi-domain neuropsychological assessment battery was administered to 46 participants with CD, examining cognitive and social cognitive domains. Clinical data on dystonia severity, pain, psychological distress and HR-QoL were collected.

RESULTS

The majority of participants with CD performed within the average range across most tests of cognition. Scores were significantly lower than standardized norms in social cognition, processing speed, and aspects of memory. High levels of anxiety (Hospital Anxiety and Depression Scale [HADS-A] ≥ 11, 30%) and depression (HADS-D ≥ 11; 29%) were observed. Psychological distress, CD severity, pain and HR-QoL were not significantly associated with neuropsychological functioning after controlling for multiple comparisons. Low HR-QoL was associated with higher levels of pain and psychological distress, but not severity of motor symptoms.

CONCLUSION

Results indicate that psychological distress and deficits in cognitive and social cognitive functioning are likely distinct features of CD. While motor symptoms do not appear to impact HR-QoL, pain and psychological distress were associated with low HR-QoL. Findings highlight the importance of addressing non-motor symptoms in the treatment of CD.