Parkinson's Disease (PD) is a long-term degenerative disorder of the central nervous system that mainly affects the motor system. The symptoms generally come on slowly over time. Early in the disease, the most obvious are shaking, rigidity, slowness of movement, and difficulty with walking. Doctors do not know what causes it and finds difficulty in early diagnosing the presence of Parkinson’s disease. An artificial neural network system with back propagation algorithm is presented in this paper for (...) helping doctors in identifying PD. Previous research with regards to predict the presence of the PD has shown accuracy rates up to 93% [1]; however, accuracy of prediction for small classes is reduced. The proposed design of the neural network system causes a significant increase of robustness. It is also has shown that networks recognition rates reached 100%. (shrink)

BACKGROUND: Hallucinations and delusions that complicate Parkinson’s disease could lead to nursing home placement and are linked to increased mortality. Cognitive impairments are typically associated with the presence of hallucinations but there are no data regarding whether such a relationship exists with delusions. OBJECTIVE: We hypothesized that hallucinations would be associated with executive and visuospatial disturbance. An exploratory examination of cognitive correlates of delusions was also completed to address the question of whether they differ from hallucinations. METHODS: 144 (...) PD subjects completed a neuropsychological battery to assess cognition and the SAPS to examine psychosis. Correlational analyses assessed associations between hallucinations and delusions with cognitive domains. RESULTS: 48 subjects reported psychotic symptoms: 25 experienced hallucinations without delusions, 23 had symptoms dominated by delusions. Severity and/or number of hallucination subtypes were significantly correlated with lower scores in language, memory, attention, executive functioning, and visuospatial ability. Correlations with delusions were non-significant. Tests of differences in the size of the correlations between groups revealed a significant relationship between language and visuospatial performance with hallucinations. CONCLUSIONS: Cognitive correlates of hallucinations and delusions appear to be different in PD, suggesting distinct pathogenic mechanisms and possibly anatomical substrates. Hence, delusions may not share the same associations with dementia as hallucinations. Since this is a new finding, further studies will be needed to confirm our results. (shrink)

Deep brain stimulation is a well-established therapy for the motor symptoms of Parkinson’s disease, but there remains an opportunity to improve symptom relief. The temporal pattern of stimulation is a new parameter to consider in DBS therapy, and we compared the effectiveness of Temporally Optimized Patterned Stimulation to standard DBS at reducing the motor symptoms of PD. Twenty-six subjects with DBS for PD received three different patterns of stimulation while on medication and using stimulation parameters optimized for standard (...) DBS. Side effects and motor symptoms were assessed after 30 min of stimulation with each pattern. Subjects experienced similar types of side effects with TOPS and standard DBS, and TOPS were well-tolerated by a majority of the subjects. On average, the most effective TOPS was as effective as standard DBS at reducing the motor symptoms of PD. In some subjects a TOPS pattern was the most effective pattern. Finally, the TOPS pattern with low average frequency was found to be as effective or more effective in about half the subjects while substantially reducing estimated stimulation energy use. TOPS DBS may provide a new programing option to improve DBS therapy for PD by improving symptom reduction and/or increasing energy efficiency. Optimizing stimulation parameters specifically for TOPS DBS may demonstrate further clinical benefit of TOPS DBS in treating the motor symptoms of Parkinson’s disease. (shrink)

Background: Treating medication-refractory freezing of gait in Parkinson’s disease remains challenging despite several trials reporting improvements in motor symptoms using subthalamic nucleus or globus pallidus internus deep brain stimulation. Pedunculopontine nucleus region DBS has been used for medication-refractory FoG, with mixed findings. FoG, as a paroxysmal phenomenon, provides an ideal framework for the possibility of closed-loop DBS.Methods: In this clinical trial, five subjects with medication-refractory FoG underwent bilateral GPi DBS implantation to address levodopa-responsive PD symptoms with open-loop stimulation. (...) Additionally, PPN DBS leads were implanted for CL-DBS to treat FoG. The primary outcome of the study was a 40% improvement in medication-refractory FoG in 60% of subjects at 6 months when “on” PPN CL-DBS. Secondary outcomes included device feasibility to gauge the recruitment potential of this four-lead DBS approach for a potentially larger clinical trial. Safety was judged based on adverse events and explantation rate.Findings: The feasibility of this approach was demonstrated as we recruited five subjects with both “on” and “off” medication freezing. The safety for this population of patients receiving four DBS leads was suboptimal and associated with a high explantation rate of 40%. The primary clinical outcome in three of the five subjects was achieved at 6 months. However, the group analysis of the primary clinical outcome did not reveal any benefit.Interpretation: This study of a human PPN CL-DBS trial in medication-refractory FoG showed feasibility in recruitment, suboptimal safety, and a heterogeneous clinical effect in FoG outcomes. (shrink)

IntroductionDeep brain stimulation has become a standard treatment option for select patients with Parkinson’s disease. The selection process and surgical procedures employed have, to date, not been standardized.MethodsA comprehensive 58-question web-based survey was developed with a focus on DBS referral practices and peri-operative management. The survey was distributed to the Parkinson’s Foundation Centers of Excellence, members of the International Parkinson’s Disease and Movement Disorders Society, and the Parkinson Study Group between December 2015 and May 2016.ResultsThere (...) were 207 individual respondents drawn from 59 countries and 6 continents, of whom 64% received formal training in DBS. Thirteen percent of centers reported that DBS could proceed despite a confidence level of < 50% for PD diagnosis. A case-based approach to DBS candidacy was applied in 51.3% of centers without a cut-off for levodopa-responsiveness. Surprisingly, 33% of centers regularly used imaging for diagnostic confirmation of idiopathic PD. Thirty-one percent of centers reported that neuropsychological evaluation did not affect DBS target selection. Approximately half of the respondents reported determination of DBS candidacy based on a multidisciplinary committee evaluation and 1/3rd reported that a committee was used for target selection. Eight percent of respondents felt that psychosocial factors should not impact DBS candidacy nor site selection. Involvement of allied health professionals in the preoperative process was sparse. There was high variability in preoperative education about DBS outcome expectations. Approximately half of the respondents did not utilize a “default brain target,” though STN was used more commonly than GPi. Specific DBS procedure techniques applied, as well as follow-up timelines, were highly variable.ConclusionResults revealed high variability on the best approaches for DBS candidate selection, brain target selection, procedure type, and postoperative practices. Cognitive and mood assessments were underutilized. There was low reliance on multidisciplinary teams or psychosocial factors to impact the decision-making process. There were small but significant differences in practice across global regions, especially regarding multidisciplinary teams. The wide variability of responses across multiple facets of DBS care highlights the need for prospective studies to inform evidence-based guidelines. (shrink)

IntroductionCognitive impairment is a highly prevalent non-motor feature of Parkinson’s disease. A better understanding of the underlying pathophysiology may help in identifying therapeutic targets to prevent or treat dementia. This study sought to identify metabolic alterations in the prefrontal cortex, a key region for cognitive functioning that has been implicated in cognitive dysfunction in PD.MethodsProton Magnetic Resonance Spectroscopy was used to investigate metabolic changes in the PFC of a cohort of cognitively normal individuals without PD, as well as (...) PD participants with either normal cognition, mild cognitive impairment, or dementia. Ratios to Creatine resonance were obtained for glutamate, glutamine and glutamate combined, N-acetylaspartate, myoinositol, and total choline, and correlated with cognitive scores across multiple domains administered to the PD participants only.ResultsWhen individuals retain cognitive capabilities, the presence of Parkinson’s disease does not create metabolic disturbances in the PFC. However, when cognitive symptoms are present, PFC Glu/Cre ratios decrease with significant differences between the PD-NC and PPD groups. In addition, Glu/Cre ratios and memory scores were marginally associated, but not after Bonferroni correction.ConclusionThese preliminary findings indicate that fluctuations in prefrontal glutamate may constitute a biomarker for the progression of cognitive impairments in PD. We caution for larger MRS investigations of carefully defined PD groups. (shrink)

Background: Freezing of gait is a common symptom in Parkinson’s disease and can be difficult to treat with dopaminergic medications or with deep brain stimulation. Novel stimulation paradigms have been proposed to address suboptimal responses to conventional DBS programming methods. Burst-cycling deep brain stimulation delivers current in various frequencies of bursts, while maintaining an intra-burst frequency identical to conventional DBS.Objective: To evaluate the safety and tolerability of BCDBS in PD patients with FOG.Methods: Ten PD subjects with STN or (...) GPi DBS and complaints of FOG were recruited for this single center, single blinded within-subject crossover study. For each subject, we compared 4, 10, and 15 Hz BCDBS to conventional DBS during the PD medication-OFF state.Results: There were no serious adverse events with BCDBS. It was feasible and straightforward to program BCDBS in the clinic setting. The benefit was comparable to conventional DBS in measures of FOG, functional mobility and in PD motor symptoms. BCDBS had lower battery consumption when compared to conventional DBS.Conclusions: BCDBS was feasible, safe and well tolerated and it has potential to be a viable future DBS programming strategy. (shrink)

BackgroundThe cognitive outcomes induced by subthalamic nucleus deep brain stimulation (STN-DBS) remain unclear, especially in PD patients with mild cognitive impairment (MCI). This study explored the cognitive effects of STN-DBS in PD patients with MCI.MethodsThis was a retrospective cohort study that included 126 PD patients who underwent STN-DBS; all patients completed cognitive and motor assessments before and at least 6 months after surgery. Cognitive changes were mainly evaluated by the Montreal cognitive assessment (MoCA) scale and the seven specific MoCA domains, (...) including visuospatial/executive function, naming, attention, language, abstract, delayed recall, and orientation. Motor improvement was evaluated by the UPDRS-III. Cognitive changes and motor improvements were compared between PD-MCI and normal cognitive (NC) patients. Logistic regression analyses were performed to explore predictors of post-operative cognitive change.ResultsAt the time of surgery, 61.90% of the included PD patients had MCI. Compared with the PD-MCI group, the PD-NC group had a significantly higher proportion of cases with post-operative cognitive decline during follow-up of up to 36 months (mean 17.34 ± 10.61 months), mainly including in global cognitive function, visuospatial/executive function and attention. Covariate-adjusted binary logistic regression analyses showed that pre-operative global cognitive status was an independent variable for post-operative cognitive decline. We also found that pre-operative cognitive specific function could predict its own decline after STN-DBS, except for the naming and orientation domains.ConclusionPD-MCI patients are at a lower risk of cognitive decline after STN-DBS compared with PD-NC patients. (shrink)

Implanted medical devices—for example, cardiac defibrillators, deep brain stimulators, and insulin pumps—offer users the possibility of regaining some control over an increasingly unruly body, the opportunity to become part “cyborg” in service of addressing pressing health needs. We recognize the value and effectiveness of such devices, but call attention to what may be less clear to potential users—that their vulnerabilities may not entirely disappear but instead shift. We explore the kinds of shifting vulnerabilities experienced by people with Parkinson’s (...) class='Hi'>disease (PD) who receive therapeutic deep brain stimulators to help control their tremors and other symptoms of PD. (shrink)

Disruptions in dopamine transmission within the basal ganglia (BG) produce deficits in voluntary actions, that is, in the interface between cortically-generated goal representation and BG-mediated response selection. Under conditions of dopamine loss in humans and other animals, responses are impaired when they require internal generation, but are relatively intact when elicited by external stimuli.

We investigated family members’ lived experience of Parkinson’s disease aiming to investigate opportunities for well-being. A lifeworld-led approach to healthcare was adopted. Interpretative phenomenological analysis was used to explore in-depth interviews with people living with PD and their partners. The analysis generated four themes: It’s more than just an illness revealed the existential challenge of diagnosis; Like a bird with a broken wing emphasizing the need to adapt to increasing immobility through embodied agency; Being together with PD exploring (...) the kinship within couples and belonging experienced through support groups; and Carpe diem! illuminated the significance of time and fractured future orientation created by diagnosis. Findings were interpreted using an existential-phenomenological theory of well-being. We highlighted how partners shared the impact of PD in their own ontological challenges. Further research with different types of families and in different situations is required to identify services required to facilitate the process of learning to live with PD. Care and support for the family unit needs to provide emotional support to manage threats to identity and agency alongside problem-solving for bodily changes. Adopting a lifeworld-led healthcare approach would increase opportunities for well-being within the PD illness journey. (shrink)

In April 1999, Dr. Curt Freed of the University of Colorado in Denver and Dr. Stanley Fahn of Columbia Presbyterian Center in New York presented the results of a four-year, $5.7 million government-financed study using tissue from aborted fetuses to treat Parkinson’s disease at a conference of the American Academy of Neurology. The results of the first government-financed, placebo-controlled clinical study using fetal tissue showed that the symptoms of some Parkinson’s patients had been relieved. This research study (...) involved forty subjects, nineteen women and twenty-one men; all suffered from Parkinson’s disease for an average of 13.5 years. In the study, each subject underwent neurosurgery: “four tiny burr holes, drilled through the wrinkle lines above the eyebrows into the skull, to clear a pathway to the brain. But only half received injections of fetal cells into the putamen, the region of the brain that controls movement; the other half received nothing. One year later, three members of the placebo group said their symptoms had improved.” In two-thirds of the transplant recipients, the fetal tissue took hold and seemed to establish a new network to produce the missing neurochemical dopamine. (shrink)

This chapter presents findings on a study of neuropsychological aspects of visual hallucinations with a focus on hallucinations in Parkinson's disease. The results of the study suggest that VHs in PD are a complex multifactor effect of different risk factors, primarily the dysfunctions of the visual system and the system that regulates rapid eye movement sleep and arousal. The study reported here also investigated whether the same risk factors are implicated in proneness to VHs as they are in VHs (...) in PD. The results suggest that the predisposition to VHs in the healthy young population is a multifactor effect of strikingly similar risk factors to those found in PD. However, in addition to the dysfunctions of the visual and arousal system, proneness to hallucinations in the normal population is also predicted by a specific personality profile. (shrink)

Why are some patients with Parkinson's disease unhappy about the outcome of deep brain stimulation (DBS)? Meccaci and Haselager (2014) attempt to answer this question by analyzing the seminal case...

Deep brain stimulation of the subthalamic nucleus or the globus pallidus is an established treatment for Parkinson’s disease that yields a marked and lasting improvement of motor symptoms. Yet, DBS benefit on gait disturbances in PD is still debated and can be a source of dissatisfaction and poor quality of life. Gait disturbances in PD encompass a variety of clinical manifestations and rely on different pathophysiological bases. While gait disturbances arising years after DBS surgery can be related to (...) disease progression, early impairment of gait may be secondary to treatable causes and benefits from DBS reprogramming. In this review, we tackle the issue of gait disturbances in PD patients with DBS by discussing their neurophysiological basis, providing a detailed clinical characterization, and proposing a pragmatic programming approach to support their management. (shrink)

Precise and timely diagnosis of Parkinson’s disease is important to control its progression among subjects. Currently, a neuroimaging technique called dopaminergic imaging that uses single photon emission computed tomography (SPECT) with 123I-Ioflupane is popular among clinicians for detecting Parkinson’s disease in early stages. Unlike other studies, which consider only low-level features like gray matter, white matter, or cerebrospinal fluid, this study explores the non-linear relation between different biomarkers (SPECT + biological) using deep learning and multivariate logistic (...) regression. Striatal binding ratios are obtained using 123I-Ioflupane SPECT scans from four brain regions which are further integrated with five biological biomarkers to increase the diagnostic accuracy. Experimental results indicate that this investigated approach can differentiate subjects with 100% accuracy. The obtained results outperform the ones reported in the literature. Furthermore, logistic regression model has been developed for estimating the Parkinson’s disease onset probability. Such models may aid clinicians in diagnosing this disease. (shrink)

Background and purposeWe previously established a radiological protocol to discriminate multiple system atrophy-parkinsonian subtype from Parkinson’s disease. However, we do not know if it can differentiate early stage disease. This study aimed to investigate whether the morphological and intensity changes in susceptibility weighted imaging of the lentiform nucleus could discriminate MSA-P from PD at early stages.MethodsWe retrospectively enrolled patients with MSA-P, PD and sex- and age-matched controls whose brain MRI included SWI, between January 2015 and July 2020 (...) at the Movement Disorder Center. Two specialists at the center reviewed the medical records and made the final diagnosis, and two experienced neuroradiologists performed MRI analysis, based on a defined and revised protocol for conducting morphological measurements of the LN and signal intensity.ResultsNineteen patients with MSA-P and 19 patients with PD, with less than 2 years of disease duration, and 19 control individuals were enrolled in this study. We found that patients with MSA- P presented significantly decreased size in the short line and corrected short line, ratio of the SL to the long line and corrected SLLr of the LN, increased standard deviation of signal intensity compared to patients with PD and controls. With receiver operating characteristic analysis, this finding had a sensitivity of 89.5% and a specificity of 73.7% to distinguish MSA- P from PD.ConclusionCompared to PD and controls, patients with MSA-P are characterized by a narrowing morphology of the posterior region of the LN. Quantitative morphological changes provide a reference for clinical auxiliary diagnosis. (shrink)

Recently it has been hypothesized that apoptotic cell death is involved in several neuropathological conditions including Parkinson's disease (PD). Initial morphological studies assessing the presence of apoptosis in Parkinsonian brain tissues yielded mixed results. Based on more recent studies in human PD brains as well in animal and cell culture models of the disease, a picture is emerging, however, that strongly suggests that many of the molecular players thought to participate in this type of neuronal cell death are (...) active in the disease. The task of researchers in the field is now to deduce how these players may be interacting with one another to bring about cell death in PD and to design effective therapies to interfere with these processes. BioEssays 23:640–646, 2001. © 2001 John Wiley & Sons, Inc. (shrink)

ObjectiveFreezing of gait is detrimental to patients with idiopathic Parkinson’s disease. Its pathophysiology represents a multilevel failure of motor processing in the cortical, subcortical, and brainstem circuits, ultimately resulting in ineffective motor output of the spinal pattern generator. Electrophysiological studies pointed to abnormalities of oscillatory activity in freezers that covered a broad frequency range including the theta, alpha, and beta bands. We explored muscular frequency domain activity with respect to freezing, and used deep brain stimulation to modulate these (...) rhythms thereby evaluating the supraspinal contributions to spinal motor neuron activity.MethodsWe analyzed 9 PD freezers and 16 healthy controls. We studied the patients after overnight withdrawal of dopaminergic medication with stimulation off, stimulation of the subthalamic nucleus or the substantia nigra pars reticulate, respectively. Patients performed a walking paradigm passing a narrow obstacle. We analyzed the frequency-domain spectra of the tibialis anterior and gastrocnemius muscles in ‘regular gait’ and during the ‘freezing’ episodes.ResultsIn stimulation off, PD freezers showed increased muscle activity of the alpha and low-beta band compared to HC in both TA and GA. This activity increase was present during straight walking and during the freezes to similar extent. STN- but not SNr-DBS decreased this activity and paralleled the clinical improvement of freezing.ConclusionWe found increased muscle activation of the alpha and lower beta band in PD freezers compared to HC, and this was attenuated with STN-DBS. Future studies may use combined recordings of local field potentials, electroencephalography, and electromyography to interrogate the supraspinal circuit mechanisms of the pathological activation pattern of the spinal pattern generator. (shrink)

Artificial intelligence (AI) has garnered tremendous attention in health care, and many hope that AI can enhance our health system’s ability to care for people with chronic and degenerative conditions, including Parkinson’s Disease (PD). This paper reports the themes and lessons derived from a qualitative study with people living with PD, family caregivers, and health care providers regarding the ethical dimensions of using AI to monitor, assess, and predict PD symptoms and progression. Thematic analysis identified ethical concerns at (...) four intersecting levels: personal, interpersonal, professional/institutional, and societal levels. Reflecting on potential benefits of predictive algorithms that can continuously collect and process longitudinal data, participants expressed a desire for more timely, ongoing, and accurate information that could enhance management of day-to-day fluctuations and facilitate clinical and personal care as their disease progresses. Nonetheless, they voiced concerns about intersecting ethical questions around evolving illness identities, familial and professional care relationships, privacy, and data ownership/governance. The multi-layer analysis provides a helpful way to understand the ethics of using AI in monitoring and managing PD and other chronic/degenerative conditions. (shrink)

BackgroundPublic health guidelines have recommended that elective medical procedures, including deep brain stimulation surgery for Parkinson’s disease, should not be scheduled during the coronavirus pandemic to prevent further virus spread and overload on health care systems. However, delaying DBS surgery for PD may not be in the best interest of individual patients and is not called for in regions where virus spread is under control and inpatient facilities are not overloaded.MethodsWe administered a newly developed phone questionnaire to 20 (...) consecutive patients with PD who received DBS surgery in Ruijin Hospital in Shanghai during the COVID-19 pandemic. The questionnaire was designed to gather the patients’ experiences and perceptions on the impact of COVID-19 on their everyday activities and access to medical care.ResultsMost of the patients felt confident about the preventive measures taken by the government and hospitals, and they have changed their daily living activities accordingly. Moreover, a large majority of patients felt confident obtaining access to regular and COVID-19-related health care services if needed. Routine clinical referral, sense of security in the hospital during the outbreak, and poor control of PD symptoms were the three main reasons given by patients for seeking DBS surgery during the COVID-19 pandemic.ConclusionThe COVID-19 pandemic has considerably impacted medical care and patients’ lives but elective procedures, such as DBS surgery for PD, do not need to be rescheduled when the health care system is not overloaded and adequate public health regulations are in place. (shrink)

IntroductionAlthough the motor signs of Parkinson’s disease are well defined, nonmotor symptoms, including higher-level language deficits, have also been shown to be frequent in patients with PD. In the present study, we used a lexical decision task to find out whether access to the mental lexicon is impaired in patients with PD, and whether task performance is affected by bradykinesia.Materials and MethodsParticipants were 34 nondemented patients with PD, either without medication or under optimum medication. A total of 19 (...) age-matched control volunteers were also recruited. We recorded reaction times to the LDT and a simple RT task. In each task, stimuli were either visual or auditory. Statistical analyses consisted of repeated-measures analyses of variance and Tukey’s HSD post hoc tests.ResultsIn the LDT, participants with PD both off and on medication exhibited intact access to the mental lexicon in both modalities. In the visual modality, patients off medication were just as fast as controls when identifying real words, but slower when identifying pseudowords. In the visual modality of the control task, RTs for pseudowords were significantly longer for PD patients off medication than for controls, revealing an unexpected but significant lexicality effect in patients that was not observed in the auditory modality. Performances of patients on medication did not differ from those of age-matched controls.DiscussionMotor execution was not slowed in patients with PD either off or on medication, in comparison with controls. Regarding lexical access, patients off medication seemed to have difficulty inhibiting a cognitive-linguistic process when it was not required, and exhibit a specific pseudoword processing deficit in the LDT, which may have been related to impaired lateral word inhibition within the mental lexicon. These deficits seemed to be compensated by medication. (shrink)

BackgroundExercise is increasingly recognized as a key component of Parkinson’s disease treatment strategies, but the underlying mechanism of how exercise affects PD is not yet fully understood.ObjectiveThe activation likelihood estimation method is used to study the mechanism of exercise affecting PD, providing a theoretical basis for studying exercise and PD, and promoting the health of patients with PD.MethodsRelevant keywords were searched on the PubMed, Cochrane Library, and Web of Science databases. Seven articles were finally included according to the (...) screening criteria, with a total sample size of 97 individuals. Using the GingerALE 3.0.2 software, an ALE meta-analysis was performed using seven studies that met the requirements, and the probability of the cross-experiment activation of each voxel was calculated.ResultsThe meta-analysis produced seven clusters, and major activations were found in the cerebellum, occipital lobe, parietal lobe, and frontal lobe brain regions.ConclusionExercise for PD mainly results in the enhanced activation of the cerebellum, occipital lobe, parietal lobe, and frontal lobe. Exercise for PD does not cause a change in the activation of a single brain area, and the observed improvement may result from coordinated changes in multiple brain areas. (shrink)

Introduction As deep brain stimulation (DBS) has shifted to being used earlier during Parkinson’s disease (PD), data is lacking regarding patient specific attitudes, preferences, and factors which may influence the timing of and decision to proceed with DBS in the United States. This study aims to identify and compare attitudes and preferences regarding the earlier use of DBS in Parkinson’s patients who have and have not undergone DBS. Methods We developed an online survey concerning attitudes about DBS (...) and its timing in PD. The survey was distributed nationally in the United States via the Michael J. Fox Foundation Trial Finder, the American Parkinson Disease Association flyers, and as a link on the Parkinson Alliance website. Differences in responses between PD DBS and non-DBS patients were assessed. Results A total of 445 patients with PD met eligibility criteria for the survey of which 160 self-identified as having undergone DBS. Fifty-five percent (n = 124) of non-DBS patients believed that DBS for PD should only be considered after all medication options have been tried. Patients favoring early DBS had fewer concerns regarding the surgery than those favoring later DBS. Conclusion Our findings highlight a variety of important considerations and concerns patients have regarding DBS and its timing. These viewpoints are important aspects of shared decision-making, as they help to identify patients’ preferences, values, and goals, which should enable providers to better navigate, with their patients, the decision path for therapeutic options to consider. (shrink)

Parkinson’s disease (PD) is a common neurodegenerative disorder of the nervous system that affects about 1 in 800 people and for which we have symptomatic but not curative therapies. At the core of the disease is the loss of a specific population of dopaminergic neurons within the brain, and replacement of dopamine through drug therapies has provided clinically significant benefit for many patients. However this therapy only ever offers a temporary amelioration of symptoms and with time this symptomatic (...) therapy becomes less efficacious and produces its own unique side-effects. As a result more effective curative therapies have been sought, including the use of cell based therapies to replace the lost dopaminergic neurons. In this review I am going to discuss PD and its possible repair using neural transplants. In particular I am going to discuss which type of cells are best considered as a reparative therapy, where they should be transplanted in the brain, when in the disease course and in which type of patient. By considering these issues, I hope to be able to make some recommendations as to the future use of this approach in PD. (shrink)

Deep brain stimulation of the subthalamic nucleus for the treatment of Parkinson’s disease can lead to the development of neuropsychiatric symptoms. These can include harmful changes in mood and behaviour that alienate family members and raise ethical questions about personal responsibility for actions committed under stimulation-dependent mental states. Qualitative interviews were conducted with twenty participants following subthalamic DBS at a movement disorders centre, in order to explore the meaning and significance of stimulation-related neuropsychiatric symptoms amongst a purposive sample (...) of persons with PD and their spousal caregivers. Interview transcripts underwent inductive thematic analysis. Clinical and experiential aspects of post-DBS neuropsychiatric symptoms were identified. Caregivers were highly burdened by these symptoms and both patients and caregivers felt unprepared for their consequences, despite having received information prior to DBS, desiring greater family and peer engagement prior to neurosurgery. Participants held conflicting opinions as to whether emergent symptoms were attributable to neurostimulation. Many felt that they reflected aspects of the person’s “real” or “younger” personality. Those participants who perceived a close relationship between stimulation changes and changes in mental state were more likely to view these symptoms as inauthentic and uncontrollable. Unexpected and troublesome neuropsychiatric symptoms occurred despite a pre-operative education programme that was delivered to all participants. This suggests that such symptoms are difficult to predict and manage even if best practice guidelines are followed by experienced centres. Further research aimed at predicting these complications may improve the capacity of clinicians to tailor the consent process. (shrink)

Postural instability in Parkinson’s disease (PD) is characterized by impaired postural responses to transient perturbations, increased postural sway in stance and difficulty transitioning between tasks. In addition, some studies suggest that loss of dopamine in the basal ganglia due to PD results in difficulty using proprioceptive information for motor control. Here, we quantify the ability of subjects with PD and age-matched control subjects to use and re-weight sensory information for postural control during steady-state conditions of continuous rotations of (...) the stance surface or visual surround. We measure the postural sway of subjects in response to a pseudorandom, surface-tilt stimulus with eyes closed, and in response to a pseudorandom, visual-tilt stimulus. We use a feedback control model of the postural control system to interpret our results, focusing on sensory weighting as a function of stimulus amplitude. We find that subjects with PD can re-weight their dependence upon sensory information in response to changes in surface- or visual-stimulus amplitude. Specifically, subjects with PD behaved like age-matched control subjects by decreasing proprioceptive contribution to stance control with increasing surface-tilt amplitude, and decreasing visual contribution with increasing visual-tilt amplitude. However, subjects with PD do not decrease their reliance on proprioception as much as age-matched controls for small increases in surface-stimulus amplitudes. Levodopa medication did not affect sensory re-weighting behaviors for postural control. The impairment in PD subject’s ability to respond differently to small changes in surface rotation amplitudes is consistent with an increased threshold for perceiving proprioceptive signals, which may result from decreased signal-to-noise in the dopaminergic pathways associated with sensory processing and/or sensory integration. (shrink)

The present study investigated the effect of Parkinson’s disease (PD) on prospective memory (PM) tasks by varying the emotional content of the PM actions. Twenty-one older adults with PD and 25 healthy older adults took part in the present study. Participants performed three virtual days in the Virtual Week task. On each virtual day, participants performed actions with positive, negative or neutral content. Immediately following each virtual day, participants completed a recognition task to assess their retrospective memory for (...) the various prospective memory tasks. PD patients were less accurate than the control group at both PM accuracy and recognition task accuracy. The effect of emotional valence was also evident, indicating that all participants were more accurate on positive PM tasks than both negative and neutral. This study confirmed PM impairment in PD patients and extended previous research showing how positive emotional stimuli can influence PM performance. (shrink)

BackgroundHuman embryonic stem cells are currently used for developing treatment against Parkinson’s disease (PD). However, the use of ES cells is surrounded with moral concerns. Research regarding the public's attitudes can form an important basis for policymaking. The aim was to explore the perceptions of the public on using donated human embryos for developing treatment of Parkinson’s Disease.MethodsSemi-structured individual qualitative interviews were conducted with 11 members of the general population in Sweden. Interviews were analyzed with thematic (...) content analyses.ResultsFour categories and additional sub-categories; Different views on the embryo requires delicacy, Using embryos to treat Parkinson’s disease, Doing things in the right way, and Communication, media, and public opinion. In general, respondents were positive towards the usage of embryotic stem cells to treat PD, but the usage were conditioned and specific terms were demanded. Informed consent from both donors were required and delicacy and sensitivity when working with embryos were needed.ConclusionsIt was perceived better to use surplus embryos to treat PD increase is than to discard them, also among those who perceived the embryo as “a potential life.” The participants raised several conditions under usage for treatment should be allowed. Even if the embryos otherwise are going to be discarded, usage requires informed consent from the donating couples. (shrink)

Schooling fish, swarms of starlings, plodding wildebeest, and musicians all display impressive synchronization. To what extent do they use acoustic cues to achieve these feats? Could the acoustic cues used in movement synchronization be relevant to the treatment of movement disorders such as Parkinson's disease in humans? In this article, we build on the emerging view in evolutionary biology that the ability to synchronize movement evolved long before language, in part due to acoustic advantages. We use this insight to (...) explore potential mechanisms that explain why music therapy has beneficial effects for PD patients. We hypothesize that rhythmic auditory cues, particularly music, can stimulate neuronal and behavioral processes that ease the symptoms and potentially the causes of PD because the neural circuits used in auditory entrainment at individual and group levels are associated with dopamine production. We summarize current treatment of PD and outline how new insights from an evolutionary perspective could improve understanding and eventual treatment of movement disorders in humans. (shrink)

Despite intense academic debate in the recent past over the use of ‘sham surgery’ control groups in research, there has been a recent resurgence in their use in the field of neurodegenerative disease. Yet the primacy of ethical arguments in favour of sham surgery controls is not yet established. Preliminary empirical research shows an asymmetry between the views of neurosurgical researchers and patients on the subject, while different ethical guidelines and regulations support conflicting interpretations. Research ethics committees faced with (...) a proposal involving sham surgery should be aware of its ethical complexities. An overview of recent and current placebo-controlled surgical trials in the field of Parkinson's Disease is provided here, followed by an analysis of the key ethical issues which such trials raise. (shrink)

BackgroundThe therapeutic effect of deep brain stimulation (DBS) of the subthalamic nucleus (STN) for Parkinson's disease (PD) is related to the modulation of pathological neural activities, particularly the synchronization in the β band (13–35 Hz). However, whether the local β activity in the STN region can directly predict the stimulation outcome remains unclear.ObjectiveWe tested the hypothesis that low-β (13–20 Hz) and/or high-β (20–35 Hz) band activities recorded from the STN region can predict DBS efficacy.MethodsLocal field potentials (LFPs) were recorded (...) in 26 patients undergoing deep brain stimulation surgery in the subthalamic nucleus area. Recordings were made after the implantation of the DBS electrode prior to its connection to a stimulator. The maximum normalized powers in the theta (4–7 Hz), alpha (7–13 Hz), low-β (13–20 Hz), high-β (20–35 Hz), and low-γ (40–55 Hz) subbands in the postoperatively recorded LFP were correlated with the stimulation-induced improvement in contralateral tremor or bradykinesia–rigidity. The distance between the contact selected for stimulation and the contact with the maximum subband power was correlated with the stimulation efficacy. Following the identification of the potential predictors by the significant correlations, a multiple regression analysis was performed to evaluate their effect on the outcome.ResultsThe maximum high-β power was positively correlated with bradykinesia–rigidity improvement (rs = 0.549, p < 0.0001). The distance to the contact with maximum high-β power was negatively correlated with bradykinesia–rigidity improvement (rs = −0.452, p < 0.001). No significant correlation was observed with low-β power. The maximum high-β power and the distance to the contact with maximum high-β power were both significant predictors for bradykinesia–rigidity improvement in the multiple regression analysis, explaining 37.4% of the variance altogether. Tremor improvement was not significantly correlated with any frequency.ConclusionHigh-β oscillations, but not low-β oscillations, recorded from the STN region with the DBS lead can inform stimulation-induced improvement in contralateral bradykinesia–rigidity in patients with PD. High-β oscillations can help refine electrode targeting and inform contact selection for DBS therapy. (shrink)