Parkinson's Disease Experience Research Articles

Sleep "ON", sleep better! Positive effects of levodopa on sleep behaviour in people with Parkinson's disease.

People with Parkinson's disease experience reduced sleep quality compared with their peers. Levodopa may have a direct effect on sleep macrostructure or may improve sleep by enhancing nocturnal motor performance. Therefore, it is important to understand the acute effects of withdrawing levodopa on sleep measures in Parkinson's disease. The purpose of this study was to compare the estimated objective and subjective sleep measures of people with Parkinson's disease sleeping under (ON-night) versus without (OFF-night) the effects of the last daily dopaminergic medication before going to bed. A total of 23 people with Parkinson's disease were instructed to wear an actigraphy device for 4 consecutive nights to objectively measure the sleep behaviour. Subjective sleep measure was assessed each morning using a Likert scale. Participants slept for 3 nights on ON-night and 1 night on OFF-night. They were instructed not to take their last dose of levodopa before going to bed in OFF-night. Sleeping in ON- versus OFF-night increased total sleep time (7.8%, p = 0.032) and sleep efficiency (3.7%, p = 0.019), and decreased duration and number of wakes after sleep onset (22.3%, p = 0.050; and 29.2%, p = 0.013, respectively). However, subjective sleep analysis indicated no significant differences between the two conditions. From a clinical point of view, our results suggest that sleeping on ON-night resulted in an improvement in estimated objective sleep measures compared with sleeping on OFF-night. From a methodological point of view, our findings emphasize the importance of relying on objective sleep measurements to accurately assess OFF-night sleep behaviour in people with Parkinson's disease.

A nomogram based on neuron-specific enolase and substantia nigra hyperechogenicity for identifying cognitive impairment in Parkinson's disease.

One in four individuals with Parkinson's disease (PD) experience cognitive impairment (CI). However, few practical models integrating clinical and neuroimaging biomarkers have been developed to address CI in PD. This study aimed to evaluate the correlation between circulating neuron-specific enolase (NSE) levels, substantia nigra hyperechogenicity (SNH), and cognitive function in PD and to develop a nomogram based on clinical and neuroimaging biomarkers for predicting CI in patients with PD. A total of 385 patients with PD who underwent transcranial sonography (TCS) from January 2021 to December 2022 at Beijing Tiantan Hospital, Capital Medical University, were recruited as the training cohort. For validation, 165 patients with PD treated from January 2023 to December 2023 were enrolled. Data for SNH, plasma NSE, and other clinical measures were collected, and cognitive function was assessed using the Montreal Cognitive Assessment (MoCA). Logistic regression analysis was employed to select potential risk factors and establish a nomogram. The receiver operating characteristic curve and calibration curve were generated to evaluate the performance of the nomogram. Patients with PD exhibiting CI displayed advanced age, elevated Unified PD Rating Scale-III (UPDRS-III) score, an increased percentage of SNH, higher levels of plasma NSE and homocysteine (Hcy), a larger SNH area, and lower education levels compared to PD patients without CI. Gender [odds ratio (OR) =0.561, 95% confidence interval (CI): 0.330-0.954, P=0.03], age (OR =1.039; 95% CI: 1.011-1.066; P=0.005), education level (OR =0.892; 95% CI: 0.842-0.954; P<0.001), UPDRS-III scores (OR =1.026; 95% CI: 1.009-1.043; P=0.003), plasma NSE concentration (OR =1.562; 95% CI: 1.374-1.776; P<0.001), and SNH (OR =0.545; 95% CI: 0.330-0.902; P=0.02) were independent predictors of CI in patients with PD. A nomogram developed using these six factors yielded a moderate discrimination performance with an area under the curve (AUC) of 0.823 (95% CI 0.781-0.864; P<0.001). The calibration curve demonstrated acceptable agreement between predicted outcomes and actual values. Validation further confirmed the reliability of the nomogram, with an AUC of 0.864 (95% CI: 0.805-0.922; P<0.001). The level of NSE in plasma and the SNH assessed by TCS are associated with CI in patients with PD. The proposed nomogram has the potential to facilitate the detection of cognitive decline in individuals with PD.

White Matter Microstructural Underpinnings of Mild Behavioral Impairment in Parkinson's Disease.

Patients with Parkinson's disease (PD) experience changes in behavior, personality, and cognition that can manifest even in the initial stages of the disease. Previous studies have suggested that mild behavioral impairment (MBI) should be considered an early marker of cognitive decline. However, the precise neurostructural underpinnings of MBI in early- to mid-stage PD remain poorly understood. The aim was to explore the changes in white matter microstructure linked to MBI and mild cognitive impairment (MCI) in early- to mid-stage PD using diffusion magnetic resonance imaging (dMRI). A total of 91 PD patients and 36 healthy participants were recruited and underwent anatomical MRI and dMRI, a comprehensive neuropsychological battery, and the completion of the Mild Behavioral Impairment-Checklist. Metrics of white matter integrity included tissue fractional anisotropy (FAt) and radial diffusivity (RDt), free water (FW), and fixel-based apparent fiber density (AFD). The connection between the left amygdala and the putamen was disrupted when comparing PD patients with MBI (PD-MBI) to PD-non-MBI, as evidenced by increased RDt (η2 = 0.09, P = 0.004) and both decreased AFD (η2 = 0.05, P = 0.048) and FAt (η2 = 0.12, P = 0.014). Compared to controls, PD patients with both MBI and MCI demonstrated increased FW for the connection between the left orbitofrontal gyrus (OrG) and the hippocampus (η2 = 0.22, P = 0.008), augmented RDt between the right OrG and the amygdala (η2 = 0.14, P = 0.008), and increased RDt (η2 = 0.25, P = 0.028) with decreased AFD (η2 = 0.10, P = 0.046) between the right OrG and the caudate nucleus. MBI is associated with abnormal microstructure of connections involving the orbitofrontal cortex, putamen, and amygdala. To our knowledge, this is the first assessment of the white matter microstructure in PD-MBI using dMRI. © 2024 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.

Online cognitive testing in Parkinson's disease: advantages and challenges.

Parkinson's disease (PD) is primarily characterized by motor symptoms. Yet, many people with PD experience cognitive decline, which is often unnoticed by clinicians, although it may have a significant impact on quality of life. For over half a century, traditional in-person PD cognitive assessment lacked accessibility, scalability, and specificity due to its inherent limitations. In this review, we propose that novel methods of online cognitive assessment could potentially address these limitations. We first outline the challenges of traditional in-person cognitive testing in PD. We then summarize the existing literature on online cognitive testing in PD. Finally, we explore the advantages, but also the limitations, of three major processes involved in online PD cognitive testing: recruitment and sampling methods, measurement and participation, and disease monitoring and management. Taking the limitations into account, we aim to highlight the potential of online cognitive testing as a more accessible and efficient approach to cognitive testing in PD.

Visual feedback improves propulsive force generation during treadmill walking in people with Parkinson disease

Persons with Parkinson's disease experience gait alterations, such as reduced step length. Gait dysfunction is a significant research priority as the current treatments targeting gait impairment are limited. This study aimed to investigate the effects of visual biofeedback on propulsive force during treadmill walking in persons with Parkinson's. Sixteen ambulatory persons with Parkinson's participated in the study. They received real-time biofeedback of anterior ground reaction force during treadmill walking at a constant speed. Peak propulsive force values were measured and normalized to body weight. Spatiotemporal parameters were also assessed, including stride length and double support percent. Persons with Parkinson's significantly increased peak propulsive force during biofeedback compared to baseline (p <.0001, Cohen's dz = 1.69). Variability in peak anterior ground reaction force decreased across repeated trials (p <.0001, dz = 1.51). While spatiotemporal parameters did not show significant changes individually, stride length and double support percent improved marginally during biofeedback trials. Persons with Parkinson's can increase propulsive force with visual biofeedback, suggesting the presence of a propulsive reserve. Though stride length did not significantly change, clinically meaningful improvements were observed. Targeting push-off force through visual biofeedback may offer a potential rehabilitation technique to enhance gait performance in Persons with Parkinson's. Future studies could explore the long-term efficacy of this intervention and investigate additional strategies to improve gait in Parkinson's disease.

Therapeutic Singing and Semi-Occluded Vocal Tract Exercises for Individuals with Parkinson's Disease: A Randomized Controlled Trial of a Single Session Intervention.

Individuals with Parkinson's disease (PD) experience speech and voice-related symptoms that diminish communication and quality of life. Semi-occluded vocal tract (SOVT) exercises are targeted interventions that, when combined with the positive psychosocial benefits of therapeutic group singing (TGS), may affect outcomes. The purpose of this study was to explore the effectiveness of SOVT exercises, specifically straw phonation combined with TGS, to improve voice quality and mood for individuals with PD. We used a true experimental pretest-posttest between-subjects design (i.e., randomized controlled trial) facilitated by a board-certified music therapist. All participants (N = 27) were randomly assigned to one of three groups (a) straw phonation combined with TGS (SP + TGS, n = 10), (b) TGS (n = 10), and (c) speaking-only control group (n = 7). Participants completed voice recordings for acoustic measures and the Visual Analogue Mood Scale for mood analysis before and after a 30-min intervention. The results demonstrated significant improvement in voice quality evidenced by decreasing Acoustic Voice Quality Index scores following a single session for both SP + TGS and TGS intervention groups when compared to the control. Happiness scores improved in the experimental groups when compared to control. Although not statistically significant, participants in the experimental groups (SP + TGS, TGS) demonstrated better mean mood scores on happiness, anxiety, and angry when compared to control, indicating a positive psychological response to the singing interventions. Overall, this study indicated the effectiveness of SP + TGS and TGS as promising therapeutic interventions for voice quality and mood in individuals with PD.

Basal forebrain integrity, cholinergic innervation and cognition in idiopathic Parkinson's disease.

Most individuals with Parkinson's disease experience cognitive decline. Mounting evidence suggests this is partially caused by cholinergic denervation due to α-synuclein pathology in the cholinergic basal forebrain. Alpha-synuclein deposition causes inflammation, which can be measured with free water fraction, a diffusion MRI-derived metric of extracellular water. Prior studies have shown an association between basal forebrain integrity and cognition, cholinergic levels and cognition, and basal forebrain volume and acetylcholine, but no study has directly investigated whether basal forebrain physiology mediates the relationship between acetylcholine and cognition in Parkinson's disease. We investigated the relationship between these variables in a cross-sectional analysis of 101 individuals with Parkinson's disease. Cholinergic levels were measured using fluorine-18 fluoroethoxybenzovesamicol (18F-FEOBV) PET imaging. Cholinergic innervation regions of interest included the medial, lateral capsular and lateral perisylvian regions and the hippocampus. Brain volume and free water fraction were quantified using T1 and diffusion MRI, respectively. Cognitive measures included composites of attention/working memory, executive function, immediate memory and delayed memory. Data were entered into parallel mediation analyses with the cholinergic projection areas as predictors, cholinergic basal forebrain volume and free water fraction as mediators and each cognitive domain as outcomes. All mediation analyses controlled for age, years of education, levodopa equivalency dose and systolic blood pressure. The basal forebrain integrity metrics fully mediated the relationship between lateral capsular and lateral perisylvian acetylcholine and attention/working memory, and partially mediated the relationship between medial acetylcholine and attention/working memory. Basal forebrain integrity metrics fully mediated the relationship between medial, lateral capsular and lateral perisylvian acetylcholine and free water fraction. For all mediations in attention/working memory and executive function, the free water mediation was significant, while the volume mediation was not. The basal forebrain integrity metrics fully mediated the relationship between hippocampal acetylcholine and delayed memory and partially mediated the relationship between lateral capsular and lateral perisylvian acetylcholine and delayed memory. The volume mediation was significant for the hippocampal and lateral perisylvian models, while free water fraction was not. Free water fraction in the cholinergic basal forebrain mediated the relationship between acetylcholine and attention/working memory and executive function, while cholinergic basal forebrain volume mediated the relationship between acetylcholine in temporal regions in memory. These findings suggest that these two metrics reflect different stages of neurodegenerative processes and add additional evidence for a relationship between pathology in the basal forebrain, acetylcholine denervation and cognitive decline in Parkinson's disease.

The Impact of Parkinson's Disease on Social Communication: An Exploratory Questionnaire Study.

Individuals with Parkinson's disease (PD) often show breakdown in the production and interpretation of aspects of social communication. However, there is no current method of assessment for evaluating social communication dysfunction in individuals with PD. The aim of this study was to develop a self-report questionnaire for individuals with PD to identify their social communication skills, and further recognize the impact of PD on social communication. Fifty-one individuals with Parkinson's disease answered 28 survey questions. These questions pertained to emotional expression and perception, social communication, sarcasm/humor, and pragmatic skills. Exploratory factor analysis and reliability analysis were conducted to identify items loading onto the factors and to check the internal consistency of the items. Individuals with PD reported changes in emotional expression and perception, social communication, sarcasm and humor, and pragmatic skill domains post-PD diagnosis. No correlations were found between age or time since diagnosis and emotional expression, social communication, sarcasm, and humor. This study provides self-reported evidence that individuals with PD experience social communication challenges. Future research should further quantify these challenges, study their impact on daily communicative functioning, and use the results to develop social communication interventions that improve the quality of life for persons with PD.

Longitudinal Analysis of Retinal Microvascular and Choroidal Imaging Parameters in Parkinson's Disease Compared with Controls

To quantify rate of change of retinal microvascular and choroidal structural parameters in subjects with Parkinson's disease (PD) compared with controls using OCT and OCT angiography (OCTA). Prospective longitudinal study. Seventy-four eyes of 40 participants with PD and 149 eyes of 78 control individuals from the Eye Multimodal Imaging in Neurodegenerative Disease database. Subjects underwent OCT and OCTA imaging at 2 time points approximately 12 months apart. Imaging parameters included central subfield thickness, ganglion cell-inner plexiform layer (GC-IPL) thickness, peripapillary retinal nerve fiber layer thickness, choroidal vascularity index, superficial capillary plexus perfusion density (PFD), vessel density (VD), and foveal avascular zone area. Participants with PD had greater rate of yearly decrease in GC-IPL (PD=-0.403μm, control=+ 0.128 μm; P= 0.01), greater yearly decline in PFD in the 3× 3 mm ETDRS circle (PD=-0.016, control=+ 0.002; P<0.001) and ring (PD=-0.016, control=+ 0.002; P < 0.001); 6× 6 mm ETDRS circle (PD=-0.021, control= 0.00; P= 0.001), and outer ring (PD=-0.022, control= 0.00; P= 0.001). Participants with PD had greater rate of yearly decline in VD in 3× 3 mm circle (PD=-0.939/mm, control=+ 0.006/mm; P < 0.001) and ring (PD=-0.942/mm, control=+ 0.013/mm; P < 0.001); 6× 6 mm circle (PD=-0.72/mm, control=-0.054/mm; P= 0.006), and outer ring (PD=-0.746/mm, control=-0.054/mm; P= 0.005). When stratified by PD severity based on Hoehn and Yahr stage, faster rates of decline were seen in Hoehn and Yahr stages 3 to 4 in the 3× 3 mm circle PFD and VD as well as 3× 3 mm ring VD. Individuals with PD experience more rapid loss of retinal microvasculature quantified on OCTA and more rapid thinning of the GC-IPL than controls. There may be more rapid loss in patients with greater disease severity. The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Lower Limb Muscle Fatigue Alters Spatiotemporal Gait Parameters and Turning Difficulty Characteristics in Parkinson's Disease.

To determine the effects of lower limb muscle fatigue on spatiotemporal gait parameters and turning difficulty characteristics during the extended Timed Up and Go (extended TUG) test in individuals with different severity stages of Parkinson's disease (PD). Forty individuals with PD, classified as Hoehn and Yahr (H&Y) stages 2 and 3 participated in this pre- and post-experimental study design. The participants performed a continuous sit-to-stand task from a chair based on 30 cycles/min set-up to induce lower limb muscle fatigue. They performed extended TUG test immediately before and after completing the fatigue protocol. Spatiotemporal gait parameters and turning difficulty characteristics were recorded using two GoPro® Hero 4 Silver cameras. Data were subjected to a repeated-measure ANOVA. Individuals with PD experience significant changes in spatiotemporal gait parameters, specifically stride velocity and length, under conditions of lower limb muscle fatigue (p=0.001). These changes were more pronounced in individuals with PD in the H&Y stage 3 group. Additionally, both PD groups exhibited difficulty with turning, requiring more than five steps to complete a 180° turn and taking more than 3 seconds to accomplish it. These findings highlight the impact of muscle fatigue on gait performance in PD and suggest that individuals in later stages of the disease may be particularly affected. Further research is needed to explore interventions that can mitigate these gait impairments and improve mobility in individuals with PD.

The Genetic Basis of Probable REM Sleep Behavior Disorder in Parkinson's Disease.

Patients with Parkinson's Disease (PD) experience REM sleep behavior disorder (RBD) more frequently than healthy controls. RBD is associated with torpid disease evolution. To test the hypothesis that differential genetic signatures might contribute to the torpid disease evolution in PD patients with RBD we compared the rate of genetic mutations in PD patients with or without probable RBD. Patients with a clinical diagnosis of PD in the Parkinson's Progression Markers Initiative (PPMI) database entered the study. We excluded those with missing data, dementia, psychiatric conditions, or a diagnosis change over the first five years from the initial PD diagnosis. Probable RBD (pRBD) was confirmed by a REM Sleep Behavior Disorder Screening Questionnaire score > 5 points. Logistic regression and Machine Learning (ML) algorithms were used to relate Single Nucleotide Polymorphism (SNPs) in PD-related genes with pRBD. We included 330 PD patients fulfilling all inclusion and exclusion criteria. The final logistic multivariate model revealed that the following SNPs increased the risk of pRBD: GBA_N370S_rs76763715 (OR, 95% CI: 3.38, 1.45-7.93), SNCA_A53T_rs104893877 (8.21, 2.26-36.34), ANK2. CAMK2D_rs78738012 (2.12, 1.08-4.10), and ZNF184_rs9468199 (1.89, 1.08-3.33). Conversely, SNP COQ7. SYT17_rs11343 reduced pRBD risk (0.36, 0.15-0.78). The ML algorithms led to similar results. The predictive models were highly specific (95-99%) but lacked sensitivity (9-39%). We found a distinctive genetic signature for pRBD in PD. The high specificity and low sensitivity of the predictive models suggest that genetic mutations are necessary but not sufficient to develop pRBD in PD. Additional investigations are needed.

The Effects of Serping1 siRNA in α-Synuclein Regulation in MPTP-Induced Parkinson's Disease.

Our understanding of the gastrointestinal system in the pathophysiology of Parkinson's disease (PD) has grown considerably over the last two decades. Patients with PD experience notable gastrointestinal symptoms, including constipation. In this study, the effects of knocked-down serping1, associated with the contraction and relaxation of smooth muscle and inflammation responses, by applying the serping1 siRNA were investigated in 1-methyl 4-phenyl 1,2,3,6-tetrahydropyridine-induced PD mice in an α-syn change aspect. In the result, serping1 expression was knocked down by the treatment of serping1 siRNA, and decreased serping1 induced the decrease α-syn in the colon. Furthermore, the changes in α-syn aggregation were also examined in the brain, and alleviated α-syn aggregation was also observed in an serping1 siRNA treatment group. The results indicated that serping1 siRNA could ease synucleinopathy related to the gastrointestinal system in PD. This study also raises the possibility that serping1 siRNA could alleviate α-syn aggregation in striatum and substantia nigra regions of the brain.

Illness perceptions in pre-operative Parkinson's disease patients.

Parkinson's disease (PD) is a neurodegenerative disease, that combines motor and non-motor disorders, and alters patients' autonomy. Even if subthalamic nucleus deep brain stimulation (STN-DBS) induces undisputable motor improvement, a post-operative social maladjustment was described by some patients. Our aim was to describe pre-operative illness perceptions in parkinsonian patients, and to determine the possible impact of cognitive restructuration over them. We analyzed 27 parkinsonian patient's candidates to DBS. The mean age was 59 ± 5.94years, and mean disease duration was 9.89 ± 4.15years. The patients had two pre-operative psychological interviews (DBS-45days, DBS-25days) and completed the Illness Perception Questionnaire-Revised (IPQ-R) before the first interview and at DBS-1day. The CRTG group (n = 13) had cognitive restructuration during second interview, on dysfunctional cognitions about their perception of post-DBS life which emerged from the first interview. The PIG group (n = 14) benefited of two non-structured interviews. No significant differences were found between the visits (DBS-45days, DBS-1day) for IPQ-R dimensions, except for the perception of "personal control" over PD which appears significantly higher for CRTG than PIG group (p = .039) at DBS-1day, whereas the scores were quite similar at DBS-45days. Illness perceptions seem to be stable over time and mostly influenced by disease experience of PD. However, the perception of personal control over PD seemed to be modulated through cognitive restructuration, giving patients' control back over disease. Before DBS, illness perceptions investigation and restructuration constitute an interesting point to work on, to enhance perceived benefits of neurosurgery.Trial registration: Clinical Research Program, N°IDRCB 2008-A00655-50, approved by the local ethics committee (CPP EST III, N° CPP: 08.07.03, first version date: 04/01/2008), registered on the ClinicalTrials.gov website (NCT02893449).

Support needs of people with younger onset Parkinson's disease: An interpretative phenomenological analysis

BackgroundPeople with younger onset Parkinson's disease reported trouble navigating the health system and managing their Parkinson's disease symptoms. This impacted their everyday responsibilities, such as maintaining employment, caring for children, or meeting financial commitments. AimTo understand the experiences of the unmet support needs of people diagnosed with younger onset Parkinson's disease and allow a deeper understanding of their lived experiences. MethodsData were collected by interviewing four participants about their perceptions of the current supports available. Interpretative phenomenological analysis was applied for in-depth exploration of the participant's experience, allowing the participant and the researcher to ‘make sense’ of their descriptions. The COREQ criteria for reporting of qualitative research were used to guide this study. FindingsFour clear overarching themes were identified: (i) ‘The pre-diagnosis of Parkinson's: denial’, (ii) ‘What is next?’, (iii) ‘Knowledge is power, mostly’, (iv) ‘Loss and acceptance of identity’. DiscussionThis study has highlighted the demoralisation people with younger onset Parkinson's disease experience when they are left in a state of not knowing what is next. People with younger onset Parkinson's disease experienced a range of changing emotions and described the emotional turmoil experienced when not supported. ConclusionThis research highlighted that a diagnosis of younger onset Parkinson's disease causes significant distress, particularly if trying to maintain employment or care for children. People with younger onset Parkinson's disease highlighted the need for psychosocial support to be instigated at the point of diagnosis.

Orofacial pain and dysfunction in patients with Parkinson's disease: A scoping review.

Parkinson's disease (PD) is commonly known as a disorder that affects the smooth performance of body movements. In addition to the motor impairments, patients with PD often experience pain. Both motor impairments and pain can occur throughout the body, hence including the orofacial region. However, currently, there is a lack of knowledge on the orofacial manifestations. Since orofacial pain and dysfunction can, amongst others, reduce the quality of life of patients with PD, it is important to explore the prevalence of these symptoms in the PD population. To provide a broad overview of the relevant literature on orofacial pain and dysfunction in patients with PD. Furthermore, we aim to generate hypotheses for future research on this topic. A literature search (in PubMed, Embase.com, Web of Science [Core collection], and Cochrane Library) was performed on 20 January 2022, in collaboration with a medical librarian. In total, 7180 articles were found, of which 50 were finally included in this scoping review. In the included studies, pain (e.g. orofacial pain (N= 2) and temporomandibular disorder pain (N= 2)), orofacial motor dysfunction (e.g. limited jaw movements (N= 10), reduced maximum muscle output (N= 3), chewing difficulties (N= 9), unspecified TMD (N= 3), sensory disturbances (N= 1)), and bruxism (N= 3) were observed more often in patients with PD than in healthy controls. Patients with PD experience more pain in the orofacial area and more dysfunction of the masticatory system than their healthy peers. This scoping review can increase health care providers' awareness of the problems that can be encountered in the orofacial area of PD patients, especially pain syndromes also occur in the orofacial region and not only in the extremities. Besides, dysfunction of the orofacial area is elaborated in this scoping review, which helps to understand that this limits PD patients' quality of life. Further, the outcomes of this scoping review can assist in encouraging collaboration between medicine and dentistry. Finally, this scoping review suggests new research areas, based on the gaps identified in the current literature on this topic. Ultimately, this will improve individualized strategies for reducing orofacial pain and/or dysfunction in PD patients.

Neural correlates of risky decision making in Parkinson's disease patients with impulse control disorders.

Some patients with Parkinson's disease (PD) experience impulse control disorders (ICDs), characterized by deficient voluntary control over impulses, drives, or temptations regarding excessive hedonic behavior. The present study aimed to better understand the neural basis of impulsive, risky decision making in PD patients with ICDs by disentangling potential dysfunctions in decision and outcome mechanisms. We collected fMRI data from 20 patients with ICDs and 28 without ICDs performing an information gathering task. Patients viewed sequences of bead colors drawn from hidden urns and were instructed to infer the majority bead color in each urn. With each new bead, they could choose to either seek more evidence by drawing another bead (draw choice) or make an urn-inference (urn choice followed by feedback). We manipulated risk via the probability of bead color splits (80/20 vs. 60/40) and potential loss following an incorrect inference ($10 vs. $0). Patients also completed the Barratt Impulsiveness Scale (BIS) to assess impulsivity. Patients with ICDs showed greater urn choice-specific activation in the right middle frontal gyrus, overlapping the dorsal premotor cortex. Across all patients, fewer draw choices (i.e., more impulsivity) were associated with greater activation during both decision making and outcome processing in a variety of frontal and parietal areas, cerebellum, and bilateral striatum. Our findings demonstrate that ICDs in PD are associated with differences in neural processing of risk-related information and outcomes, implicating both reward and sensorimotor dopaminergic pathways.

Interventions for preventing falls in Parkinson's disease.

Interventions for preventing falls in Parkinson's disease.

Task-specific effects of biological sex and sex hormones on object recognition memories in a 6-hydroxydopamine-lesion model of Parkinson's disease in adult male and female rats

Many patients with Parkinson's disease (PD) experience cognitive or memory impairments with few therapeutic options available to mitigate them. This has fueled interest in determining how factors including sex and sex hormones modulate higher order function in this disease. The objective of this study was to use the Novel Object Recognition (NOR) and Object-in-Place (OiP) paradigms to compare the effects of a bilateral neostriatal 6-hydroxydopamine (6-OHDA) lesion model of PD in gonadally intact male and female rats, in orchidectomized male rats and in orchidectomized males supplemented with 17β-estradiol or testosterone propionate on measures of recognition memory similar to those at risk in PD. These studies showed that 6-ODHA lesions impaired discrimination in both tasks in males but not females. Further, 6-OHDA lesions disrupted NOR performance similarly in all males regardless of whether they were gonadally intact, orchidectomized or hormone-supplemented. In contrast, OiP performance was disrupted in males that were orchidectomized or 6-OHDA-lesioned but was spared in orchidectomized and orchidectomized, 6-OHDA lesioned males supplemented with 17β-estradiol. The distinct effects that sex and/or sex hormones have on 6-OHDA lesion-induced NOR vs. OiP deficits identified here also differ from corresponding impacts recently described for 6-OHDA lesion-induced deficits in spatial working memory and episodic memory. Together, the collective data provide strong evidence for effects of sex and sex hormones on cognition and memory in PD as being behavioral task and behavioral domain specific. This specificity could explain why a cohesive clinical picture of endocrine impacts on higher order function in PD has remained elusive.

Neuroimaging and Neuropsychological Performance in Parkinson's Disease Patients with Mild Cognitive Impairment: A Systematic Review

Introduction: One of the most common non motor symptoms of Parkinson's disease (PD) is cognitive decline. Scientific evidence has demonstrated that patients with PD experience rapid cognitive decline in multiple cognitive domains, specifically executive functions, attention, visuospatial, language and memory. However, the extent of cognitive decline with its correlation to brain regions on neuroimaging have not been reviewed extensively in the literature.&#x0D; Objective: The objective of this review is to summarize the existing literature that explores cognitive performance in patients with PD with mild cognitive impairment (MCI) using different neuroimaging techniques.&#x0D; Methods: A comprehensive search was conducted on PubMed and Web of Science databases. This review is focused on articles that explored neuroimaging and neuropsychological performance in patients with Parkinson’s disease. We screened articles and excluded those that did not fit the criteria of this study, and a total of 13 articles have met the criteria.&#x0D; Results: Overall, PD-MCI patients experienced more cognitive decline than PD patients without MCI. Global cognitive ability was associated with frontal lobe, basal ganglia, para-hippocampal gyrus, occipital lobe, and the cerebellum. In addition, some specific cognitive domains were associated with specific brain regions. Attention and executive functions were associated with insula network and the parietal and frontal regions. Learning and memory were associated with grey matter atrophy and right cingulate gyrus and the limbic lobe. Language was associated with frontal cortex, precuneus, and anterior cingulate gyrus. Visuospatial ability was associated with Salience network (SN) and White Matter Hyperintensity (WMH).&#x0D; Conclusion: This review of the literature showed that PD-MCI patients display different cognitive impairment as well as different neuroanatomical changes when compared to PD-Normal Cognition (NC). These findings may suggest that cognitive impairment in PD-MCI patients require different clinical treatment and care. This review also can have diagnostic and treatment implications for this group of patients.

The Acoustic Voice Quality Index (AVQI) in People with Parkinson's Disease Before and After Intensive Voice and Articulation Therapies: Secondary Outcome of a Randomized Controlled Trial

The majority of individuals with Parkinson's disease (PD) experience voice and speech problems during the course of the disease. Despite the importance of voice quality in communication and the documented disordered voice quality in PD, few studies have explored the effects of speech treatment on this variable. A parallel arm, unblinded randomized controlled trial (RCT) was conducted with two active comparators, LSVT LOUD (n=23) and LSVT ARTIC (n=20), and an inactive comparator group of untreated individuals with PD (n=22). A group of 20 healthy adults was also included for pre-treatment analysis. Voice recordings were obtained pre-treatment, immediately post-treatment and at 6-month follow-up. The acoustic voice quality index (AVQI) is reported here as a secondary outcome measure of the RCT. Linear mixed-effects regression analysis was performed with AVQI and sound pressure level (SPL) as dependent variables. Pearson correlation coefficient analysis was also conducted to explore the relationship between voice quality and SPL. Statistically significant improvements in AVQI and SPL from pre-treatment to post-treatment and follow-up were only observed in the LSVT LOUD group. Voice quality significantly improved only from pre-treatment to follow-up in the LSVT ARTIC group, whilst significant improvements in SPL were observed during maximum phonation only immediately post-treatment. No significant changes were observed in the untreated group. This study investigated the effects of intensive speech treatment targeting voice or targeting articulation on voice quality, as measured by the AVQI, in individuals with PD. Findings indicate that voice-focused treatment leads to greater improvements in voice quality in this population.