The contribution of white matter changes to clinical phenotype in progressive supranuclear palsy.

White matter hyperintensities (WMH) are considered magnetic brain imaging (MRI) biomarkers of cerebral small vessel disease but their clinical role in neurodegenerative-related disorders is poorly understood. This study describes the distribution of WMH on brain MRI in Progressive Supranuclear Palsy (PSP) in comparison with Parkinson's disease (PD) and explores their possible impact on disease's features. Sixty PSP and 33 PD patients were included. Motor symptoms, cardiovascular risk factors and the age-related white matter changes (ARWMC) score was computed to rate WMH for both groups. Pearson's correlation and linear or logistic regression analysis were used to check for relationships between ARWMC and PSP clinical scores. The mean (standard deviation) ARWMC total score in the PSP cohort was 4.66 (3.25). Any degree of WMH was present in 68% of PSP (ARWMC +). Compared to ARWMC-, ARWMC + did not have greater disease severity or more cardiovascular risk factors. WMH were frequently localized in fronto-parietal lobes and were mild in severity. Linear regression analysis showed that ARWMC total score was related to the PSP-rating scale, irrespective of age, disease duration and the Charlson modified comorbidity index. Logistic regression analysis confirmed that ARWMC total score was related to the use of wheelchair, irrespective of above-mentioned covariates. Vascular risk factors as well as severity and distribution of WMH did not have an impact on the PSP phenotype. No differences were found with PD patients. Our results suggest that WMH in PSP might be markers of neurodegenerative-related pathology rather than being simple expression of atherosclerotic cerebrovascular changes.

A window into the mind-brain-body interplay: Development of diagnostic, prognostic biomarkers, and rehabilitation strategies in functional motor disorders.

BACKGROUND AND AIMS: Functional motor disorders (FMD) present a prevalent, yet misunderstood spectrum of neurological conditions characterized by abnormal movements (i.e., functional limb weakness, tremor, dystonia, gait impairments), leading to substantial disability and diminished quality of life. Despite their high prevalence, FMD often face delayed diagnosis and inadequate treatment, resulting in significant social and economic burdens. The old concept of psychological factors as the primary cause (conversion disorder) has been abandoned due to the need for more evidence about their causal role. According to a predictive coding account, the emerging idea is that symptoms and disability may depend on dysfunctions of a specific neural system integrating interoception, exteroception, and motor control. Consequently, symptoms are construed as perceptions of the body's state. Besides the main pathophysiological features (abnormal attentional focus, beliefs/expectations, and sense of agency), the lived experience of symptoms and their resulting disability may depend on an altered integration at the neural level of interoception, exteroception, and motor control. METHODS AND MATERIALS: Our proposal aims to elucidate the pathophysiological mechanisms of FMD through a three-stage research approach. Initially, a large cohort study will collect behavioral, neurophysiological, and MRI biomarkers from patients with FMD and healthy controls, employing eXplainable Artificial Intelligence (XAI) to develop a diagnostic algorithm. Subsequently, validation will occur using patients with organic motor disorders. Finally, the algorithm's prognostic value will be explored post-rehabilitation in one subgroup of patients with FMD. RESULTS: Data collection for the present study started in May 2023, and by May 2025, data collection will conclude. DISCUSSION: Our approach seeks to enhance early diagnosis and prognostication, improve FMD management, and reduce associated disability and socio-economic costs by identifying disease-specific biomarkers. TRIAL REGISTRATION: This trial was registered in clinicaltrials.gov (NCT06328790).

Investigating the prevalence of MFN2 mutations in amyotrophic lateral sclerosis: insights from an Italian cohort.

The MFN2 gene encodes mitofusin 2, a key protein for mitochondrial fusion, transport, maintenance and cell communication. MFN2 mutations are primarily linked to Charcot-Marie-Tooth disease type 2A. However, a few cases of amyotrophic lateral sclerosis and amyotrophic lateral sclerosis/frontotemporal dementia phenotypes with concomitant MFN2 mutations have been previously reported. This study examines the clinical and genetic characteristics of an Italian cohort of amyotrophic lateral sclerosis patients with rare, non-synonymous MFN2 mutations. A group of patients (n = 385) diagnosed with amyotrophic lateral sclerosis at our Neurology Units between 2008 and 2023 underwent comprehensive molecular testing, including MFN2. After excluding pathogenic mutations in the main amyotrophic lateral sclerosis-related genes (i.e. C9orf72, SOD1, FUS and TARDBP), MFN2 variants were classified based on the American College of Medical Genetics and Genomics guidelines, and demographic and clinical data of MFN2-mutated patients were retrieved. We identified 12 rare, heterozygous, non-synonymous MFN2 variants in 19 individuals (4.9%). Eight of these variants, carried by nine patients (2.3%), were either pathogenic, likely pathogenic or variants of unknown significance according to the American College of Medical Genetics and Genomics guidelines. Among these patients, four exhibited a familial pattern of inheritance. The observed phenotypes included classic and bulbar amyotrophic lateral sclerosis, amyotrophic lateral sclerosis/frontotemporal dementia, flail arm, flail leg and progressive muscular atrophy. Median survival after disease onset was extremely variable, ranging from less than 1 to 13 years. This study investigates the prevalence of rare, non-synonymous MFN2 variants within an Italian cohort of amyotrophic lateral sclerosis patients, who have been extensively investigated, enhancing our knowledge of the underlying phenotypic spectrum. Further research is needed to understand whether MFN2 mutations contribute to motor neuron disease and to what extent. Improving our knowledge regarding the genetic basis of amyotrophic lateral sclerosis is crucial both in a diagnostic and therapeutic perspective.

Spinocerebellar ataxia 27B: a frequent and slowly progressive autosomal-dominant cerebellar ataxia-experience from an Italian cohort.

BACKGROUND: Autosomal-dominant spinocerebellar ataxia (ADCA) due to intronic GAA repeat expansion in FGF14 (SCA27B) is a recent, relatively common form of late-onset ataxia. OBJECTIVE: Here, we aimed to: (1) investigate the relative frequency of SCA27B in different clinically defined disease subgroups with late-onset ataxia collected among 16 tertiary Italian centers; (2) characterize phenotype and diagnostic findings of patients with SCA27B; (3) compare the Italian cohort with other cohorts reported in recent studies. METHODS: We screened 396 clinically diagnosed late-onset cerebellar ataxias of unknown cause, subdivided in sporadic cerebellar ataxia, ADCA, and multisystem atrophy cerebellar type. We identified 72 new genetically defined subjects with SCA27B. Then, we analyzed the clinical, neurophysiological, and imaging features of 64 symptomatic cases. RESULTS: In our cohort, the prevalence of SCA27B was 13.4% (53/396) with as high as 38.5% (22/57) in ADCA. The median age of onset of SCA27B patients was 62 years. All symptomatic individuals showed evidence of impaired balance and gait; cerebellar ocular motor signs were also frequent. Episodic manifestations at onset occurred in 31% of patients. Extrapyramidal features (17%) and cognitive impairment (25%) were also reported. Brain magnetic resonance imaging showed cerebellar atrophy in most cases (78%). Pseudo-longitudinal assessments indicated slow progression of ataxia and minimal functional impairment. CONCLUSION: Patients with SCA27B in Italy present as an adult-onset, slowly progressive cerebellar ataxia with predominant axial involvement and frequent cerebellar ocular motor signs. The high consistency of clinical features in SCA27B cohorts in multiple populations paves the way toward large-scale, multicenter studies.

Expanding the Spectrum of GBA1-Associated Neurodegenerative Diseases in an Italian Family.

BACKGROUND: Heterozygous mutations in GBA1 gene are known as most common genetic risk factor for Parkinson's disease (PD). However, role of GBA1 mutations in non-α-synuclein disorders is unclear. CASES: Case index, 76 year-old woman referred to our movement disorders outpatient clinic for 2-year history of gait impairment, falls and motor slowness, with partial response to levodopa. Clinical and instrumental examinations were consistent with Progressive Supranuclear Palsy-Corticobasal Syndrome (PSP-CBS). Case 2 is older sister reporting depressive symptoms; however, she had dementia (MMSE 18/30), gait apraxia and vertical supranuclear gaze palsy (VSNGP). Case 3 is her deceased older sister who had been diagnosed with Corticobasal Syndrome (CBS). Case 4, older brother had been diagnosed with Parkinson's disease-dementia (PDD) with good response to levodopa. Two affected living siblings harboring same genetic variant. CONCLUSIONS: To our knowledge, this is the first family showing such intrafamilial variability ranging from CBS to PDD to dementia.

Genome sequence analyses identify novel risk loci for multiple system atrophy.

Multiple system atrophy (MSA) is an adult-onset, sporadic synucleinopathy characterized by parkinsonism, cerebellar ataxia, and dysautonomia. The genetic architecture of MSA is poorly understood, and treatments are limited to supportive measures. Here, we performed a comprehensive analysis of whole genome sequence data from 888 European-ancestry MSA cases and 7,128 controls to systematically investigate the genetic underpinnings of this understudied neurodegenerative disease. We identified four significantly associated risk loci using a genome-wide association study approach. Transcriptome-wide association analyses prioritized USP38-DT, KCTD7, and lnc-KCTD7-2 as novel susceptibility genes for MSA within these loci, and single-nucleus RNA sequence analysis found that the associated variants acted as cis-expression quantitative trait loci for multiple genes across neuronal and glial cell types. In conclusion, this study highlights the role of genetic determinants in the pathogenesis of MSA, and the publicly available data from this study represent a valuable resource for investigating synucleinopathies.

Longitudinal change of energy expenditure, body composition and dietary habits in Progressive Supranuclear Palsy patients.

INTRODUCTION: Alterations in metabolic status, body composition, and food intake are present in all neurodegenerative diseases. Aim of this study was to detect the progression of these changes in Progressive Supranuclear Palsy (PSP). METHODS: We conducted a longitudinal study of 15 patients with PSP. The assessments were performed at baseline (T0) and after 7(IQR = 5) months of follow-up (T1). We collected anthropometric measures including body weight, height, body mass index and waist circumference, metabolic parameters through indirect calorimeters, body composition using bioimpedance analysis, and dietary habits with a validated questionnaire. PSP-rating scale (PSP-rs) was used to evaluate disease severity and dysphagia. RESULTS: The majority of patients (66.66%) presented PSP-Richardson Syndrome and 33.33% the other variant syndromes of the disease. At T1 there was a decrease in intake of total daily calories (p < 0.001), proteins (p < 0.001), fibers (p = 0.001), calcium (p = 0.008), iron (p < 0.001), zinc (0.034), vitamin E (p = 0.006) and folates (p = 0.038) compared to T0. No other changes were found. As for T1 data, no significant differences were shown according to disease phenotypes or the presence of clinically significant dysphagia for solids. CONCLUSIONS: Within a mid-term follow up, PSP patients presented reduced caloric and proteins intake regardless the presence of dysphagia. The PSP-rs is likely not adequate to assess dysphagia, which should be investigated by specific clinical scales or instrumental examinations. With the goal of maintaining adequate nutritional status, the administration of protein and vitamin supplements should be considered even in the absence of dysphagia evidenced by the rating scales.

Direct Current Stimulation of Prefrontal Cortex Is Not Effective in Progressive Supranuclear Palsy: A Randomized Trial.

BACKGROUND: Progressive supranuclear palsy (PSP) is a rare 4R-tauopathy. Transcranial direct current stimulation (tDCS) may improve specific symptoms. OBJECTIVES: This randomized, double-blinded, sham-controlled trial aimed at verifying the short-, mid-, and long-term effect of multiple sessions of anodal tDCS over the left dorsolateral prefrontal cortex (DLPFC) cortex in PSP. METHODS: Twenty-five patients were randomly assigned to active or sham stimulation (2 mA for 20 minute) for 5 days/week for 2 weeks. Participants underwent assessments at baseline, after the 2-week stimulation protocol, then after 45 days and 3 months from baseline. Primary outcomes were verbal and semantic fluency. The efficacy was verified with analysis of covariance. RESULTS: We failed to detect a significant effect of active stimulation on primary outcomes. Stimulation was associated to worsening of specific behavioral complaints. CONCLUSIONS: A 2-week protocol of anodal left DLPFC tDCS is not effective in PSP. Specific challenges in running symptomatic clinical trials with classic design are highlighted. © 2024 International Parkinson and Movement Disorder Society.

Psychometric properties of the Caregiver's inventory neuropsychological diagnosis dementia (CINDD) in mild cognitive impairment and dementia.

OBJECTIVES: The Caregiver's Inventory Neuropsychological Diagnosis Dementia (CINDD) is an easy tool designed to quantify cognitive, behavioural and functional deficits of patients with cognitive impairment. Aim of the present study was to analyse the psychometric properties of the CINDD in Mild Cognitive Impairment (MCI) and Dementia (D). DESIGN, SETTING AND PARTICIPANTS: The CINDD, composed by 9 sub-domains, was administered to fifty-six caregivers of patients with different types of dementia (D) and 44 caregivers of patients with MCI. All patients underwent an extensive neuropsychological assessment, the Neuropsychiatric Inventory (NPI) and functional autonomy scales. The reliability, convergent construct validity and possible cut-off of CINND were measured by Cronbach's alpha (α), Pearson's correlation and ROC analysis, respectively. RESULTS: The D and MCI patients differed only for age (p=0.006). The internal consistency of CINDD was high (α= 0.969). The α-value for each CINDD domain was considered acceptable, except the mood domain (α=0.209). The CINDD total score correlated with cognitive screening tests; each domain of the CINDD correlated with the corresponding score from either tests or NPI (p<0.05), except for visuo-spatial perception skills and apathy. A screening cut-off equal to 59, can be used discriminate D from MCI (Sensitivity=0.70, Specificity=0.57). CONCLUSION: The CINDD is a feasible, accurate and reliable tool for the assessment of cognitive and behavioural difficulties in patients with different degree of cognitive impairment. It may be used to quantify and monitor caregiver-reported ecological data in both clinical and research settings.

Development of the Digital Inclusion Questionnaire (DIQUEST) in Parkinson's Disease.

BACKGROUND: No tool is currently able to measure digital inclusion in clinical populations suitable for telemedicine. We developed the "Digital Inclusion Questionnaire" (DIQUEST) to estimate access and skills in Parkinson's Disease (PD) patients and verified its properties with a pilot study. METHODS: Thirty PD patients completed the initial version of the DIQUEST along with the Mobile Device Proficiency Questionnaire (MDPQ) and a practical computer task. A Principal Components Analysis (PCA) was conducted to define the DIQUEST factor structure and remove less informative items. We used Cronbach's α to measure internal reliability and Spearman's correlation test to determine the convergent and predictive validity with the MDPQ and the practical task, respectively. RESULTS: The final version of the DIQUEST consisted of 20 items clustering in five components: "advanced skills," "navigation skills," "basic skills/knowledge," "physical access," and "economical access." All components showed high reliability (α > 0.75) as did the entire questionnaire (α = 0.94). Correlation analysis demonstrated high convergent (rho: 0.911; p<0.001) and predictive (rho: 0.807; p<0.001) validity. CONCLUSIONS: We have here presented the development of the DIQUEST as a screening tool to assess the level of digital inclusion, particularly addressing the access and skills domains. Future studies are needed for its validation beyond PD.

The Correlation between Retinal and Choroidal Thickness with Age-Related White Matter Hyperintensities in Progressive Supranuclear Palsy.

Progressive supranuclear palsy (PSP) is a rare neurodegenerative disease. Recently, several retinal layers in PSP compared to healthy controls. were found to be thinner. However, no studies evaluating the correlation between retinal layers and cerebral white matter changes, nor eventual choroidal changes in PSP, have been conducted so far. The goals of the present study were to explore potential differences in choroidal structure between PSP and healthy controls, and to describe the relationship between retinal layers' thickness and volume, using spectral-domain optical coherence tomography (SD-OCT) and age-related white matter change scores (ARWMC) using magnetic resonance imaging (MRI) of the brain. Choroidal structures of 26 PSP patients and 26 healthy controls using standard SD-OCT with an enhanced depth imaging (EDI) approach were analyzed; then, retinal the structures of 16 of these PSP patients using standard SD-OCT were examined; finally, the same patients underwent brain MRI, and their cerebral white matter changes were calculated. Non-statistically significant differences between PSP patients' and healthy controls' choroidal structure were found. On the contrary, PSP patients' inner retinal layers (INR), retinal pigmented epithelium (RPE) and all retinal layers' thicknesses in the macular region were found to be significantly correlated with ARWMC, independently from age and axial length (AL). PSP patients' neurological alterations go hand in hand with retinal ones, independently from age and axial length. Our results suggest a mutual relationship between cerebral and retinal structure pathological alterations. On the other hand, no significant differences in the choroidal evaluation compared to healthy controls have been found.

Development and Validation of a Prognostic Model to Predict Overall Survival in Multiple System Atrophy.

Background: Multiple system atrophy (MSA) is a devastating disease characterized by a variable combination of motor and autonomic symptoms. Previous studies identified numerous clinical factors to be associated with shorter survival. Objective: To enable personalized patient counseling, we aimed at developing a risk model of survival based on baseline clinical symptoms. Methods: MSA patients referred to the Movement Disorders Unit in Innsbruck, Austria, between 1999 and 2016 were retrospectively analyzed. Kaplan-Meier curves and multivariate Cox regression analysis with least absolute shrinkage and selection operator penalty for variable selection were performed to identify prognostic factors. A nomogram was developed to estimate the 7 years overall survival probability. The performance of the predictive model was validated and calibrated internally using bootstrap resampling and externally using data from the prospective European MSA Study Group Natural History Study. Results: A total of 210 MSA patients were included in this analysis, of which 124 patients died. The median survival was 7 years. The following clinical variables were found to significantly affect overall survival and were included in the nomogram: age at symptom onset, falls within 3 years of onset, early autonomic failure including orthostatic hypotension and urogenital failure, and lacking levodopa response. The time-dependent area under curve for internal and external validation was >0.7 within the first 7 years of the disease course. The model was well calibrated showing good overlap between predicted and actual survival probability at 7 years. Conclusion: The nomogram is a simple tool to predict survival on an individual basis and may help to improve counseling and treatment of MSA patients.

Frequency and imaging correlates of neuropsychiatric symptoms in Progressive Supranuclear Palsy.

Neuropsychiatric symptoms are intrinsic to Progressive Supranuclear Palsy (PSP) and a spoonful of studies investigated their imaging correlates. Describe (I) the frequency and severity of neuropsychiatric symptoms in PSP and (II) their structural imaging correlates. Twenty-six PSP patients underwent Neuropsychiatric Inventory (NPI) and brain 3D T1-weighted MRI. Spearman's rho with Bonferroni correction was used to investigate correlations between NPI scores and volumes of gray matter regions. More than 80% of patients presented at least one behavioral symptom of any severity. The most frequent and severe were depression/dysphoria, apathy, and irritability/lability. Significant relationships were found between the severity of irritability and right pars opercularis volume (p < 0.001) as well as between the frequency of agitation/aggression and left lateral occipital volume (p < 0.001). Depression, apathy, and irritability are the most common neuropsychiatric symptoms in PSP. Moreover, we found a relationship between specific positive symptoms as irritability and agitation/aggression and greater volume of the right pars opercularis cortex and lower volume of the left occipital cortex, respectively, which deserve further investigations.

Improving the Efficacy of Botulinum Toxin for Cervical Dystonia: A Scoping Review.

Cervical dstonia (CD) is a chronic disorder with a significant detrimental impact on quality of life, requiring long-term treatment. Intramuscular injections of botulinum neurotoxin (BoNT) every 12 to 16 weeks have become the first-line option for CD. Despite the remarkable efficacy of BoNT as a treatment for CD, a significantly high proportion of patients report poor outcomes and discontinue the treatment. The reasons that drive sub-optimal response or treatment failure in a proportion of patients include but are not limited to inappropriate muscle targets and/or BoNT dosing, improper method of injections, subjective feeling of inefficacy, and the formation of neutralizing antibodies against the neurotoxin. The current review aims to complement published research focusing on the identification of the factors that might explain the failure of BoNT treatment in CD, highlighting possible solutions to improve its outcomes. Thus, the use of the new phenomenological classification of cervical dystonia known as COL-CAP might improve the identification of the muscle targets, but more sensitive information might come from the use of kinematic or scintigraphic techniques and the use of electromyographic or ultrasound guidance might ensure the accuracy of the injections. Suggestions are made for the development of a patient-centered model for the management of cervical dystonia and to emphasize that unmet needs in the field are to increase awareness about the non-motor spectrum of CD, which might influence the perception of the efficacy from BoNT injections, and the development of dedicated rehabilitation programs for CD that might enhance its effectiveness.

Levodopa Equivalent Dose of Safinamide: A Multicenter, Longitudinal, Case-Control Study.

Background: Effects of dopaminergic medications used to treat Parkinson's disease (PD) may be compared with each other by using conversion factors, calculated as Levodopa equivalent dose (LED). However, current LED proposals on MAO-B inhibitors (iMAO-B) safinamide and rasagiline are still based on empirical approaches. Objectives: To estimate LED of safinamide 50 and 100 mg. Methods: In this multicenter, longitudinal, case-control study, we retrospectively reviewed clinical charts of 500 consecutive PD patients with motor complications and treated with (i) safinamide 100 mg (N = 130), safinamide 50 mg (N = 144), or rasagiline 1 mg (N = 97) for 9 ± 3 months and a control group of patients never treated with any iMAO-B (N = 129). Results: Major baseline features (age, sex, disease duration and stage, severity of motor signs and motor complications) were similar among the groups. Patients on rasagiline had lower UPDRS-II scores and Levodopa dose than control subjects. After a mean follow-up of 8.8-to-10.1 months, patients on Safinamide 50 mg and 100 mg had lower UPDRS-III and OFF-related UPDRS-IV scores than control subjects, who in turn had larger increase in total LED than the three iMAO-B groups. After adjusting for age, disease duration, duration of follow-up, baseline values and taking change in UPDRS-III scores into account (sensitivity analysis), safinamide 100 mg corresponded to 125 mg LED, whereas safinamide 50 mg and rasagiline 1 mg equally corresponded to 100 mg LED. Conclusions: We used a rigorous approach to calculate LED of safinamide 50 and 100 mg. Large prospective pragmatic trials are needed to replicate our findings.

Wearable sensors for assessing disease severity and progression in Progressive Supranuclear Palsy.

INTRODUCTION: Progressive supranuclear palsy (PSP) is an atypical parkinsonism characterized by prominent gait and postural impairment. The PSP rating scale (PSPrs) is a clinician-administered tool to evaluate disease severity and progression. More recently, digital technologies have been used to investigate gait parameters. Therefore, object of this study was to implement a protocol using wearable sensors evaluating disease severity and progression in PSP. METHODS: Patients were evaluated with the PSPrs as well as with three wearable sensors located on the feet and lumbar area. Spearman coefficient was used to assess the relationship between PSPrs and quantitative measurements. Furthermore, sensor parameters were included in a multiple linear regression model to assess their ability in predicting the PSPrs total score and sub-scores. Finally, differences between baseline and three-month follow-up were calculated for PSPrs and each quantitative variable. The significance level in all analyses was set at ≤ 0.05. RESULTS: Fifty-eight evaluations from thirty-five patients were analyzed. Quantitative measurements showed multiple significant correlations with the PSPrs scores (r between 0.3 and 0.7; p < 0.05). Linear regression models confirmed the relationships. After three months visit, significant worsening from baseline was observed for cadence, cycle duration and PSPrs item 25, while PSPrs item 10 showed a significant improvement. CONCLUSION: We propose wearable sensors can provide an objective, sensitive quantitative evaluation and immediate notification of gait changes in PSP. Our protocol can be easily introduced in outpatient and research settings as a complementary tool to clinical measures as well as an informative tool on disease severity and progression in PSP.

Identification of a Gait Pattern for Detecting Mild Cognitive Impairment in Parkinson's Disease.

The aim of this study was to determine a gait pattern, i.e., a subset of spatial and temporal parameters, through a supervised machine learning (ML) approach, which could be used to reliably distinguish Parkinson's Disease (PD) patients with and without mild cognitive impairment (MCI). Thus, 80 PD patients underwent gait analysis and spatial-temporal parameters were acquired in three different conditions (normal gait, motor dual task and cognitive dual task). Statistical analysis was performed to investigate the data and, then, five ML algorithms and the wrapper method were implemented: Decision Tree (DT), Random Forest (RF), Naïve Bayes (NB), Support Vector Machine (SVM) and K-Nearest Neighbour (KNN). First, the algorithms for classifying PD patients with MCI were trained and validated on an internal dataset (sixty patients) and, then, the performance was tested by using an external dataset (twenty patients). Specificity, sensitivity, precision, accuracy and area under the receiver operating characteristic curve were calculated. SVM and RF showed the best performance and detected MCI with an accuracy of over 80.0%. The key features emerging from this study are stance phase, mean velocity, step length and cycle length; moreover, the major number of features selected by the wrapper belonged to the cognitive dual task, thus, supporting the close relationship between gait dysfunction and MCI in PD.