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Parkinson's fmri

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https://www.readbyqxmd.com/read/28597560/l-dopa-responsiveness-is-associated-with-distinctive-connectivity-patterns-in-advanced-parkinson-s-disease
#1
Harith Akram, Chengyuan Wu, Jonathan Hyam, Thomas Foltynie, Patricia Limousin, Enrico De Vita, Tarek Yousry, Marjan Jahanshahi, Marwan Hariz, Timothy Behrens, John Ashburner, Ludvic Zrinzo
BACKGROUND: Neuronal loss and dopamine depletion alter motor signal processing between cortical motor areas, basal ganglia, and the thalamus, resulting in the motor manifestations of Parkinson's disease. Dopamine replacement therapy can reverse these manifestations with varying degrees of improvement. METHODS: To evaluate functional connectivity in patients with advanced Parkinson's disease and changes in functional connectivity in relation to the degree of response to l-dopa, 19 patients with advanced Parkinson's disease underwent resting-state functional magnetic resonance imaging in the on-medication state...
June 2017: Movement Disorders: Official Journal of the Movement Disorder Society
https://www.readbyqxmd.com/read/28566724/aberrant-intra-and-internetwork-functional-connectivity-in-depressed-parkinson-s-disease
#2
Luqing Wei, Xiao Hu, Yajing Zhu, Yonggui Yuan, Weiguo Liu, Hong Chen
Much is known concerning the underlying mechanisms of Parkinson's disease (PD) with depression, but our understanding of this disease at the neural-system level remains incomplete. This study used resting-state functional MRI (rs-fMRI) and independent component analysis (ICA) to investigate intrinsic functional connectivity (FC) within and between large-scale neural networks in 20 depressed PD (dPD) patients, 35 non-depressed PD (ndPD) patients, and 34 healthy controls (HC). To alleviate the influence caused by ICA model order selection, this work reported results from analyses at 2 levels (low and high model order)...
May 31, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28556242/cerebral-compensation-during-motor-function-in-friedreich-ataxia-the-image-frda-study
#3
Ian H Harding, Louise A Corben, Martin B Delatycki, Monique R Stagnitti, Elsdon Storey, Gary F Egan, Nellie Georgiou-Karistianis
BACKGROUND: Friedreich ataxia is characterized by progressive motor incoordination that is linked to peripheral, spinal, and cerebellar neuropathology. Cerebral abnormalities are also reported in Friedreich ataxia, but their role in disease expression remains unclear. METHODS: In this cross-sectional functional magnetic resonance imaging study, 25 individuals with Friedreich ataxia and 33 healthy controls performed simple (self-paced single-finger) and complex (visually cued multifinger) tapping tasks to respectively gauge basic and attentionally demanding motor behavior...
May 27, 2017: Movement Disorders: Official Journal of the Movement Disorder Society
https://www.readbyqxmd.com/read/28486506/an-fmri-study-into-emotional-processing-in-parkinson-s-disease-does-increased-medial-prefrontal-activation-compensate-for-striatal-dysfunction
#4
Anja J H Moonen, Peter H Weiss, Michael Wiesing, Ralph Weidner, Gereon R Fink, Jennifer S A M Reijnders, Wim M Weber, Albert F G Leentjens
BACKGROUND: Apart from a progressive decline of motor functions, Parkinson's disease (PD) is also characterized by non-motor symptoms, including disturbed processing of emotions. This study aims at assessing emotional processing and its neurobiological correlates in PD with the focus on how medicated Parkinson patients may achieve normal emotional responsiveness despite basal ganglia dysfunction. METHODS: Nineteen medicated patients with mild to moderate PD (without dementia or depression) and 19 matched healthy controls passively viewed positive, negative, and neutral pictures in an event-related blood oxygen level-dependent functional magnetic resonance imaging study (BOLD-fMRI)...
2017: PloS One
https://www.readbyqxmd.com/read/28484422/cortical-and-striatal-reward-processing-in-parkinson-s-disease-psychosis
#5
Sara Garofalo, Azucena Justicia, Gonzalo Arrondo, Anna O Ermakova, Pranathi Ramachandra, Carina Tudor-Sfetea, Trevor W Robbins, Roger A Barker, Paul C Fletcher, Graham K Murray
Psychotic symptoms frequently occur in Parkinson's disease (PD), but their pathophysiology is poorly understood. According to the National Institute of Health RDoc programme, the pathophysiological basis of neuropsychiatric symptoms may be better understood in terms of dysfunction of underlying domains of neurocognition in a trans-diagnostic fashion. Abnormal cortico-striatal reward processing has been proposed as a key domain contributing to the pathogenesis of psychotic symptoms in schizophrenia. This theory has received empirical support in the study of schizophrenia spectrum disorders and preclinical models of psychosis, but has not been tested in the psychosis associated with PD...
2017: Frontiers in Neurology
https://www.readbyqxmd.com/read/28467917/resting-state-functional-reorganization-in-parkinson-s-disease-an-activation-likelihood-estimation-meta-analysis
#6
REVIEW
Masoud Tahmasian, Simon B Eickhoff, Kathrin Giehl, Frank Schwartz, Damian M Herz, Alexander Drzezga, Thilo van Eimeren, Angela R Laird, Peter T Fox, Habibolah Khazaie, Mojtaba Zarei, Carsten Eggers, Claudia R Eickhoff
Parkinson's disease (PD) is a common progressive neurodegenerative disorder. Studies using resting-state functional magnetic resonance imaging (fMRI) to investigate underlying pathophysiology of motor and non-motor symptoms in PD yielded largely inconsistent results. This quantitative neuroimaging meta-analysis aims to identify consistent abnormal intrinsic functional patterns in PD across studies. We used PubMed to retrieve suitable resting-state studies and stereotactic data were extracted from 28 individual between-group comparisons...
April 8, 2017: Cortex; a Journal Devoted to the Study of the Nervous System and Behavior
https://www.readbyqxmd.com/read/28462585/pramipexole-modulates-interregional-connectivity-within-the-sensorimotor-network
#7
Zheng Ye, Anke Hammer, Thomas F Münte
Pramipexole is widely prescribed to treat Parkinson's disease but has been reported to cause impulse control disorders such as pathological gambling. Recent neurocomputational models suggested that D2 agonists may distort functional connections between the striatum and the motor cortex, resulting in impaired reinforcement learning and pathological gambling. To examine how D2 agonists modulate the striatal-motor connectivity, we carried out a pharmacological resting-state functional magnetic resonance imaging study with a double-blind randomized within-subject crossover design...
May 2017: Brain Connectivity
https://www.readbyqxmd.com/read/28426552/altered-neural-responses-to-heat-pain-in-drug-na%C3%A3-ve-patients-with-parkinson-s-disease
#8
Katarina Forkmann, Wiebke Grashorn, Katharina Schmidt, Odette Fründt, Carsten Buhmann, Ulrike Bingel
Pain is a frequent but still neglected non-motor symptom of Parkinson's disease (PD). However, neural mechanisms underlying pain in PD are poorly understood. Here we explored whether the high prevalence of pain in PD might be related to dysfunctional descending pain control. Using fMRI we explored neural responses during the anticipation and processing of heat pain in 21 PD patients (Hoehn&Yahr I-III) and 23 healthy controls (HC). PD patients were naïve to dopaminergic medication in order to avoid confounding drug effects...
April 18, 2017: Pain
https://www.readbyqxmd.com/read/28420978/resting-state-fmri-reveals-increased-subthalamic-nucleus-and-sensorimotor-cortex-connectivity-in-patients-with-parkinson-s-disease-under-medication
#9
Bo Shen, Yang Gao, Wenbin Zhang, Liyu Lu, Jun Zhu, Yang Pan, Wenya Lan, Chaoyong Xiao, Li Zhang
Functional connectivity (FC) between the subthalamic nucleus (STN) and the sensorimotor cortex is increased in off-medication patients with Parkinson's disease (PD). However, the status of FC between STN and sensorimotor cortex in on-medication PD patients remains unclear. In this study, resting state functional magnetic resonance imaging was employed on 31 patients with PD under medication and 31 healthy controls. Two-sample t-test was used to study the change in FC pattern of the STN, the FC strength of the bilateral STN was correlated with overall motor symptoms, while unilateral STN was correlated with offside motor symptoms...
2017: Frontiers in Aging Neuroscience
https://www.readbyqxmd.com/read/28417291/reward-prediction-errors-in-drug-addiction-and-parkinson-s-disease-from-neurophysiology-to-neuroimaging
#10
REVIEW
Isabel García-García, Yashar Zeighami, Alain Dagher
PURPOSE OF REVIEW: Surprises are important sources of learning. Cognitive scientists often refer to surprises as "reward prediction errors," a parameter that captures discrepancies between expectations and actual outcomes. Here, we integrate neurophysiological and functional magnetic resonance imaging (fMRI) results addressing the processing of reward prediction errors and how they might be altered in drug addiction and Parkinson's disease. RECENT FINDINGS: By increasing phasic dopamine responses, drugs might accentuate prediction error signals, causing increases in fMRI activity in mesolimbic areas in response to drugs...
June 2017: Current Neurology and Neuroscience Reports
https://www.readbyqxmd.com/read/28412948/a-computerized-tablet-system-for-evaluating-treatment-of-essential-tremor-by-magnetic-resonance-guided-focused-ultrasound
#11
Fred Tam, Yuexi Huang, Michael L Schwartz, Tom A Schweizer, Kullervo Hynynen, Simon J Graham
BACKGROUND: Transcranial magnetic resonance guided focused ultrasound is an emerging technology under evaluation for treatment of essential tremor, a prevalent movement disorder. A qualitative evaluation is performed by a clinician periodically during the procedure to maximize treatment effects and minimize adverse effects. The present work demonstrates a magnetic resonance-compatible method to enable more precise, quantitative measurement of tremor severity. METHODS: Tremor severity was measured in 12 patients pre-, post-, and intra-operatively, using a magnetic resonance-compatible tablet and a computerized adaptation of drawing tasks from the widely-used Fahn-Tolosa-Marin Tremor Rating Scale...
April 17, 2017: BMC Neurology
https://www.readbyqxmd.com/read/28375089/mri-and-clinical-manifestations-of-delayed-encephalopathy-after-carbon-monoxide-poisoning
#12
Xiahong Wang, Zhenyu Li, Jacqueline Berglass, Wenlong He, Jianmin Zhao, Min Zhang, Chongyang Gao, Caixia Zhang, Huimin Zhang, Xuewei Yi
To explore the relationship between the clinical manifestations and functional magnetic resonance images of delayed encephalopathy after carbon monoxide intoxication. Six patients received the MRI were diagnosed with delayed encephalopathy after carbon monoxide (CO) poisoning. Clinical manifestations were observed in each patient. MRI revealed multiple lesions. The majority of the lesions were located in the globus pallidus, sub cortical white matter, and basal ganglia. The cognitive injury, akinetic mutism, fecal and uroclepsia, forced crying, forced laughing and extra pyramidal syndromes such as chorea and parkinsonism were manifested in clinic...
November 2016: Pakistan Journal of Pharmaceutical Sciences
https://www.readbyqxmd.com/read/28374660/reward-learning-deficits-in-parkinson-s-disease-depend-on-depression
#13
M H M Timmer, G Sescousse, M E van der Schaaf, R A J Esselink, R Cools
BACKGROUND: Depression is one of the most common and debilitating non-motor symptoms of Parkinson's disease (PD). The neurocognitive mechanisms underlying depression in PD are unclear and treatment is often suboptimal. METHODS: We investigated the role of striatal dopamine in reversal learning from reward and punishment by combining a controlled medication withdrawal procedure with functional magnetic resonance imaging in 22 non-depressed PD patients and 19 PD patients with past or present depression...
April 4, 2017: Psychological Medicine
https://www.readbyqxmd.com/read/28349948/discriminating-cognitive-status-in-parkinson-s-disease-through-functional-connectomics-and-machine-learning
#14
Alexandra Abós, Hugo C Baggio, Bàrbara Segura, Anna I García-Díaz, Yaroslau Compta, Maria José Martí, Francesc Valldeoriola, Carme Junqué
There is growing interest in the potential of neuroimaging to help develop non-invasive biomarkers in neurodegenerative diseases. In this study, connection-wise patterns of functional connectivity were used to distinguish Parkinson's disease patients according to cognitive status using machine learning. Two independent subject samples were assessed with resting-state fMRI. The first (training) sample comprised 38 healthy controls and 70 Parkinson's disease patients (27 with mild cognitive impairment). The second (validation) sample included 25 patients (8 with mild cognitive impairment)...
March 28, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28335024/impaired-dual-tasking-in-parkinson-s-disease-is-associated-with-reduced-focusing-of-cortico-striatal-activity
#15
Freek Nieuwhof, Bastiaan R Bloem, Miriam F Reelick, Esther Aarts, Inbal Maidan, Anat Mirelman, Jeffrey M Hausdorff, Ivan Toni, Rick C Helmich
Impaired dual tasking, namely the inability to concurrently perform a cognitive and a motor task (e.g. 'stops walking while talking'), is a largely unexplained and frequent symptom of Parkinson's disease. Here we consider two circuit-level accounts of how striatal dopamine depletion might lead to impaired dual tasking in patients with Parkinson's disease. First, the loss of segregation between striatal territories induced by dopamine depletion may lead to dysfunctional overlaps between the motor and cognitive processes usually implemented in parallel cortico-striatal circuits...
March 17, 2017: Brain: a Journal of Neurology
https://www.readbyqxmd.com/read/28265121/brain-structural-and-functional-signatures-of-impulsive-compulsive-behaviours-in-parkinson-s-disease
#16
F Imperiale, F Agosta, E Canu, V Markovic, A Inuggi, M Jecmenica-Lukic, A Tomic, M Copetti, S Basaia, V S Kostic, M Filippi
This study assessed brain structural and functional alterations in patients with Parkinson's disease and impulsive-compulsive behaviours (PD-ICB) compared with controls and PD no-ICB cases. Eighty-five PD patients (35 PD-ICB) and 50 controls were recruited. All subjects underwent three-dimensional T1-weighted, diffusion tensor (DT), and resting state functional magnetic resonance imaging (RS fMRI). We assessed cortical thickness with surface-based morphometry, subcortical volumes using FIRST, DT MRI metrics using region of interest and tractography approaches, and RS fMRI using a model free approach...
March 7, 2017: Molecular Psychiatry
https://www.readbyqxmd.com/read/28256710/levodopa-response-differs-in-parkinson-s-motor-subtypes-a-task-based-effective-connectivity-study
#17
Brianne Mohl, Brian D Berman, Erika Shelton, Jody Tanabe
Parkinson's disease (PD) is a circuit-level disorder with clinically-determined motor subtypes. Despite evidence suggesting each subtype may have different pathophysiology, few neuroimaging studies have examined levodopa-induced differences in neural activation between tremor dominant (TD) and postural instability/gait difficulty (PIGD) subtype patients during a motor task. The goal of this functional MRI (fMRI) study was to examine task-induced activation and connectivity in the cortico-striatal-thalamo-cortical motor circuit in healthy controls, TD patients, and PIGD patients before and after levodopa administration...
March 3, 2017: Journal of Comparative Neurology
https://www.readbyqxmd.com/read/28249785/identifying-the-presence-of-parkinson-s-disease-using-low-frequency-fluctuations-in-bold-signals
#18
Yan Tang, Li Meng, Chang-Min Wan, Zhen-Hua Liu, Wei-Hua Liao, Xin-Xiang Yan, Xiao-Yu Wang, Bei-Sha Tang, Ji-Feng Guo
Parkinson's disease (PD) is a chronic, progressive, and degenerative neurological disorder that is characterized by the degeneration of dopamine neurons in the substantia nigra and the formation of intracellular Lewy inclusion bodies. Resting-state functional magnetic resonance imaging (RS-fMRI) has demonstrated evidence of changes in metabolic patterns in individuals with PD. The purpose of this study was to determine whether the presence of PD could be "predicted" based on resting fluctuations in the blood oxygenation level dependent signal...
April 3, 2017: Neuroscience Letters
https://www.readbyqxmd.com/read/28230070/an-fmri-compatible-force-measurement-system-for-the-evaluation-of-the-neural-correlates-of-step-initiation
#19
Andrea Cristina de Lima-Pardini, Raymundo Machado de Azevedo Neto, Daniel Boari Coelho, Catarina Costa Boffino, Sukhwinder S Shergill, Carolina de Oliveira Souza, Rachael Brant, Egberto Reis Barbosa, Ellison Fernando Cardoso, Luis Augusto Teixeira, Rajal G Cohen, Fay Bahling Horak, Edson Amaro
Knowledge of brain correlates of postural control is limited by the technical difficulties in performing controlled experiments with currently available neuroimaging methods. Here we present a system that allows the measurement of anticipatory postural adjustment of human legs to be synchronized with the acquisition of functional magnetic resonance imaging data. The device is composed of Magnetic Resonance Imaging (MRI) compatible force sensors able to measure the level of force applied by both feet. We tested the device in a group of healthy young subjects and a group of elderly subjects with Parkinson's disease using an event-related functional MRI (fMRI) experiment design...
February 23, 2017: Scientific Reports
https://www.readbyqxmd.com/read/28223037/asymmetric-dopaminergic-degeneration-and-levodopa-alter-functional-corticostriatal-connectivity-bilaterally-in-experimental-parkinsonism
#20
Cyril Monnot, Xiaoqun Zhang, Sahar Nikkhou-Aski, Peter Damberg, Per Svenningsson
Asymmetric dopamine loss is commonly found in early Parkinson's disease (PD), but its effects on functional networks have been difficult to delineate in PD patients because of variations in age, disease duration and therapy. Here we used unilateral 6-hydroxydopamine-lesioned (6-OHDA) rats and controls and treated them with a single intraperitoneal injection of levodopa (L-DOPA) before performing diffusion weighted MRI and resting state functional MRI (rs-fMRI). In accordance with a neurodegeneration of the nigrostriatal dopaminergic pathway, diffusion tensor imaging showed increased radial diffusivity and decreased fractional anisotropy in the lesioned substantia nigra...
June 2017: Experimental Neurology
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