201
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Guo L, Normando EM, Shah PA, De Groef L, Cordeiro MF. Oculo-visual abnormalities in Parkinson's disease: Possible value as biomarkers. Mov Disord 2018; 33:1390-1406. [DOI: 10.1002/mds.27454] [Citation(s) in RCA: 41] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2017] [Revised: 05/16/2018] [Accepted: 05/18/2018] [Indexed: 12/16/2022] Open
Affiliation(s)
- Li Guo
- Glaucoma and Retinal Degenerative Disease Research Group, Institute of Ophthalmology; University College London; London UK
| | - Eduardo M. Normando
- Glaucoma and Retinal Degenerative Disease Research Group, Institute of Ophthalmology; University College London; London UK
- Western Eye Hospital, Imperial College Healthcare National Health Service Trust; London UK
- Imperial College Ophthalmology Research Group, Department of Surgery and Cancer, Imperial College London; London UK
| | - Parth Arvind Shah
- Glaucoma and Retinal Degenerative Disease Research Group, Institute of Ophthalmology; University College London; London UK
| | - Lies De Groef
- Glaucoma and Retinal Degenerative Disease Research Group, Institute of Ophthalmology; University College London; London UK
- Neural Circuit Development and Regeneration Research Group, Department of Biology; University of Leuven; Leuven Belgium
| | - M. Francesca Cordeiro
- Glaucoma and Retinal Degenerative Disease Research Group, Institute of Ophthalmology; University College London; London UK
- Western Eye Hospital, Imperial College Healthcare National Health Service Trust; London UK
- Imperial College Ophthalmology Research Group, Department of Surgery and Cancer, Imperial College London; London UK
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202
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Strafella AP, Bohnen NI, Pavese N, Vaillancourt DE, van Eimeren T, Politis M, Tessitore A, Ghadery C, Lewis S. Imaging Markers of Progression in Parkinson's Disease. Mov Disord Clin Pract 2018; 5:586-596. [PMID: 30637278 DOI: 10.1002/mdc3.12673] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2018] [Revised: 07/22/2018] [Accepted: 07/30/2018] [Indexed: 12/12/2022] Open
Abstract
Background Parkinson's disease (PD) is the second-most common neurodegenerative disorder after Alzheimer's disease; however, to date, there is no approved treatment that stops or slows down disease progression. Over the past decades, neuroimaging studies, including molecular imaging and MRI are trying to provide insights into the mechanisms underlying PD. Methods This work utilized a literature review. Results It is now becoming clear that these imaging modalities can provide biomarkers that can objectively detect brain changes related to PD and monitor these changes as the disease progresses, and these biomarkers are required to establish a breakthrough in neuroprotective or disease-modifying therapeutics. Conclusions Here, we provide a review of recent observations deriving from PET, single-positron emission tomography, and MRI studies exploring PD and other parkinsonian disorders.
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Affiliation(s)
- Antonio P Strafella
- Morton and Gloria Shulman Movement Disorder Unit & E.J. Safra Parkinson Disease Program, Neurology Division, Department of Medicine, Toronto Western Hospital, UHN University of Toronto Toronto Ontario Canada.,Division of Brain, Imaging and Behaviour-Systems Neuroscience, Krembil Research Institute, UHN University of Toronto Toronto Ontario Canada.,Research Imaging Centre, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health University of Toronto Toronto Ontario Canada
| | - Nico I Bohnen
- Department of Radiology & Neurology University of Michigan Ann Arbor Michigan USA.,Veterans Administration Ann Arbor Healthcare System Ann Arbor Michigan USA.,Morris K. Udall Center of Excellence for Parkinson's Disease Research University of Michigan Ann Arbor Michigan USA
| | - Nicola Pavese
- Newcastle Magnetic Resonance Centre & Positron Emission Tomography Centre Newcastle University, Campus for Ageing & Vitality Newcastle upon Tyne United Kingdom
| | - David E Vaillancourt
- Applied Physiology and Kinesiology, Biomedical Engineering, and Neurology University of Florida Gainesville Florida USA
| | - Thilo van Eimeren
- Department of Nuclear Medicine and Department of Neurology University of Cologne Cologne Germany.,Institute for Cognitive Neuroscience, Jülich Research Centre Jülich Germany.,German Center for Neurodegenerative Diseases (DZNE) Bonn-Cologne Bonn Germany
| | - Marios Politis
- Neurodegeneration Imaging Group (NIG), Institute of Psychiatry, Psychology and Neuroscience (IoPPN), King's College London London United Kingdom
| | - Alessandro Tessitore
- Department of Medical, Surgical, Neurological, Metabolic and Aging Sciences-MRI Research Center SUN-FISM University of Campania "Luigi Vanvitelli" Naples Italy
| | - Christine Ghadery
- Morton and Gloria Shulman Movement Disorder Unit & E.J. Safra Parkinson Disease Program, Neurology Division, Department of Medicine, Toronto Western Hospital, UHN University of Toronto Toronto Ontario Canada.,Division of Brain, Imaging and Behaviour-Systems Neuroscience, Krembil Research Institute, UHN University of Toronto Toronto Ontario Canada.,Research Imaging Centre, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health University of Toronto Toronto Ontario Canada
| | - Simon Lewis
- Parkinson's Disease Research Clinic, Brain and Mind Centre University of Sydney Sydney NSW Australia
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203
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Cova I, Priori A. Diagnostic biomarkers for Parkinson's disease at a glance: where are we? J Neural Transm (Vienna) 2018; 125:1417-1432. [PMID: 30145631 PMCID: PMC6132920 DOI: 10.1007/s00702-018-1910-4] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 07/24/2018] [Indexed: 12/19/2022]
Abstract
Parkinson's disease (PD) is a neurodegenerative disorder whose aetiology remains unclear: degeneration involves several neurotransmission systems, resulting in a heterogeneous disease characterized by motor and non-motor symptoms. PD causes progressive disability that responds only to symptomatic therapies. Future advances include neuroprotective strategies for use in at-risk populations before the clinical onset of disease, hence the continuing need to identify reliable biomarkers that can facilitate the clinical diagnosis of PD. In this evaluative review, we summarize information on potential diagnostic biomarkers for use in the clinical and preclinical stages of PD.
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Affiliation(s)
- Ilaria Cova
- Neurology Unit, L. Sacco University Hospital, Milan, Italy
| | - Alberto Priori
- Department of Health Sciences, "Aldo Ravelli" Research Center for Neurotechnology and Experimental Brain Therapeutics, University of Milan and ASST Santi Paolo e Carlo, Milan, Italy.
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204
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Defining visual illusions in Parkinson's disease: Kinetopsia and object misidentification illusions. Parkinsonism Relat Disord 2018; 55:111-116. [DOI: 10.1016/j.parkreldis.2018.05.023] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 05/17/2018] [Accepted: 05/27/2018] [Indexed: 01/29/2023]
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205
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Influence of obstacle color on locomotor and gaze behaviors during obstacle avoidance in people with Parkinson’s disease. Exp Brain Res 2018; 236:3319-3325. [DOI: 10.1007/s00221-018-5385-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2018] [Accepted: 09/21/2018] [Indexed: 10/28/2022]
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206
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Patterns of striatal and cerebellar functional connectivity in early-stage drug-naïve patients with Parkinson's disease subtypes. Neuroradiology 2018; 60:1323-1333. [PMID: 30244415 DOI: 10.1007/s00234-018-2101-6] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2018] [Accepted: 09/13/2018] [Indexed: 02/05/2023]
Abstract
PURPOSE Both the striatal-thalamo-cortical (STC) circuit and cerebello-thalamo-cortical (CTC) circuit play a critical role in Parkinson's disease (PD). METHODS Resting-state functional MRI was used to assess functional connectivity (FC) focusing on the basal ganglia (BG) and cerebellum among early-stage drug-naïve PD patients with tremor-dominant (TD) PD patients with postural instability and gait dysfunction (PIGD) and healthy controls (HCs). RESULTS Compared to HCs, both PD subgroups had higher FC between the cerebellum and paracentral lobule, sensorimotor areas; lower FC between the BG and superior frontal gyrus, and within the BG circuit; PD-TD patients showed higher FC between the BG and fusiform, paracentral lobule, cerebellum Lobule VI, and between the cerebellum and supplementary motor areas (SMA), insula; lower FC between the BG and rectus, sensorimotor areas, and within the cerebellum circuit; PD-PIGD patients showed higher FC between the cerebellum and middle frontal gyrus, precuneus; lower FC between the BG and cerebellum Crus II. Besides, compared to PD-PIGD patients and HCs, PD-TD patients had higher FC between the BG and calcarine region. In all PD patients, FC in paracentral lobule, SMA, and cerebellum Lobule VI positively correlated with tremor scores, and FC in calcarine area positively correlated with tremor scores, but negatively correlated with PIGD scores. CONCLUSION Our findings mainly suggested that the BG and cerebellum had hyper-connectivity with the cortical motor cortex, and the BG had prominent hyper-connectivity with the visual cortex in early-stage PD-TD patients. These findings may be helpful for facilitating the further understanding of potential mechanisms in the early-stage PD-TD. However, our results are preliminary, and further investigations are needed.
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207
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Parr T, Benrimoh DA, Vincent P, Friston KJ. Precision and False Perceptual Inference. Front Integr Neurosci 2018; 12:39. [PMID: 30294264 PMCID: PMC6158318 DOI: 10.3389/fnint.2018.00039] [Citation(s) in RCA: 40] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2018] [Accepted: 08/30/2018] [Indexed: 12/24/2022] Open
Abstract
Accurate perceptual inference fundamentally depends upon accurate beliefs about the reliability of sensory data. In this paper, we describe a Bayes optimal and biologically plausible scheme that refines these beliefs through a gradient descent on variational free energy. To illustrate this, we simulate belief updating during visual foraging and show that changes in estimated sensory precision (i.e., confidence in visual data) are highly sensitive to prior beliefs about the contents of a visual scene. In brief, confident prior beliefs induce an increase in estimated precision when consistent with sensory evidence, but a decrease when they conflict. Prior beliefs held with low confidence are rapidly updated to posterior beliefs, determined by sensory data. These induce much smaller changes in beliefs about sensory precision. We argue that pathologies of scene construction may be due to abnormal priors, and show that these can induce a reduction in estimated sensory precision. Having previously associated this precision with cholinergic signaling, we note that several neurodegenerative conditions are associated with visual disturbances and cholinergic deficits; notably, the synucleinopathies. On relating the message passing in our model to the functional anatomy of the ventral visual stream, we find that simulated neuronal loss in temporal lobe regions induces confident, inaccurate, empirical prior beliefs at lower levels in the visual hierarchy. This provides a plausible, if speculative, computational mechanism for the loss of cholinergic signaling and the visual disturbances associated with temporal lobe Lewy body pathology. This may be seen as an illustration of the sorts of hypotheses that may be expressed within this computational framework.
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Affiliation(s)
- Thomas Parr
- Institute of Neurology, Wellcome Trust Centre for Neuroimaging, University College London, London, United Kingdom
| | - David A Benrimoh
- Institute of Neurology, Wellcome Trust Centre for Neuroimaging, University College London, London, United Kingdom
| | - Peter Vincent
- Institute of Neurology, Wellcome Trust Centre for Neuroimaging, University College London, London, United Kingdom
| | - Karl J Friston
- Institute of Neurology, Wellcome Trust Centre for Neuroimaging, University College London, London, United Kingdom
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208
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Visuospatial exploration and art therapy intervention in patients with Parkinson's disease: an exploratory therapeutic protocol. Complement Ther Med 2018; 40:70-76. [PMID: 30219472 DOI: 10.1016/j.ctim.2018.07.011] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2018] [Revised: 07/17/2018] [Accepted: 07/23/2018] [Indexed: 11/21/2022] Open
Abstract
Though abnormalities of visuospatial function occur in Parkinson's disease, the impact of such deficits on functional independence and psychological wellbeing has been historically under- recognized, and effective treatments for this impairment are unknown. These symptoms can be encountered at any stage of the disease, affecting many activities of daily living, and negatively influencing mood, self-efficacy, independence, and overall quality of life. Furthermore, visuospatial dysfunction has been recently linked to gait impairment and falls, symptoms that are known to be poor prognostic factors. Here, we aim to present an original modality of neurorehabilitation designed to address visuospatial dysfunction and related symptoms in Parkinson's disease, known as "Art Therapy". Art creation relies on sophisticated neurologic mechanisms including shape recognition, motion perception, sensory-motor integration, abstraction, and eye-hand coordination. Furthermore, art therapy may enable subjects with disability to understand their emotions and express them through artistic creation and creative thinking, thus promoting self-awareness, relaxation, confidence and self-efficacy. The potential impact of this intervention on visuospatial dysfunction will be assessed by means of combined clinical, behavioral, gait kinematic, neuroimaging and eye tracking analyses. Potential favorable outcomes may drive further trials validating this novel paradigm of neurorehabilitation.
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209
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Langston RG, Virmani T. Use of a Modified STROOP Test to Assess Color Discrimination Deficit in Parkinson's Disease. Front Neurol 2018; 9:765. [PMID: 30258399 PMCID: PMC6143680 DOI: 10.3389/fneur.2018.00765] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2018] [Accepted: 08/23/2018] [Indexed: 11/13/2022] Open
Abstract
Objective: To objectively measure color vision dysfunction in idiopathic Parkinson's disease (iPD) using an easily administered, essentially free, modified Stroop test. Methods: Sixty-one iPD patients and 26 age-matched controls (HC) were enrolled after IRB approval and performed congruent (CST) and incongruent (IST) modified Stroop tests consisting of 40 words in 10 colors arranged in a 5 x 8 grid. The scorer was blinded to participant diagnosis. Errors on IST were defined as type 1 (written word reported rather than color) or type 2 (color reported different from the written word or its color). Results: The iPD group and the control group completed testing with similar CST performance. On the IST, 75.4% of iPD patients had type 2 errors (p = 0.001, OR 4.907, 95%CI 1.838-13.097) compared to 38.5% HC, with a positive predictive value of 82%. The mean number of type 2 errors was also higher in the iPD group, even with MoCA scores as a covariate in the analysis. Type 1 errors were not significantly different between the groups. A univariate logistic regression model with age, gender, MoCA, normalized IST completion time and the presence/absence of type 2 errors also resulted in type 2 errors as the only significant factor in the equation (p = 0.026). Conclusions: The modified Stroop test incorporated into the clinical evaluation of a patient may provide a quick and inexpensive objective measure of a non-motor feature of iPD, which could help in the clinical diagnosis of iPD in conjunction with the motor assessments currently used by neurologists.
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Affiliation(s)
- Rebekah G Langston
- College of Medicine, University of Arkansas for Medical Sciences, Little Rock, AR, United States
| | - Tuhin Virmani
- Department of Neurology, University of Arkansas for Medical Sciences, Little Rock, AR, United States
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210
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Ortuño-Lizarán I, Esquiva G, Beach TG, Serrano GE, Adler CH, Lax P, Cuenca N. Degeneration of human photosensitive retinal ganglion cells may explain sleep and circadian rhythms disorders in Parkinson's disease. Acta Neuropathol Commun 2018; 6:90. [PMID: 30201049 PMCID: PMC6130068 DOI: 10.1186/s40478-018-0596-z] [Citation(s) in RCA: 52] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2018] [Accepted: 09/03/2018] [Indexed: 11/19/2022] Open
Abstract
Parkinson's disease (PD) patients often suffer from non-motor symptoms like sleep dysregulation, mood disturbances or circadian rhythms dysfunction. The melanopsin-containing retinal ganglion cells are involved in the control and regulation of these processes and may be affected in PD, as other retinal and visual implications have been described in the disease. Number and morphology of human melanopsin-containing retinal ganglion cells were evaluated by immunohistochemistry in eyes from donors with PD or control. The Sholl number of intersections, the number of branches, and the number of terminals from the Sholl analysis were significantly reduced in PD melanopsin ganglion cells. Also, the density of these cells significantly decreased in PD compared to controls. Degeneration and impairment of the retinal melanopsin system may affect to sleep and circadian dysfunction reported in PD pathology, and its protection or stimulation may lead to better disease prospect and global quality of life of patients.
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Affiliation(s)
- Isabel Ortuño-Lizarán
- Department of Physiology, Genetics and Microbiology, University of Alicante, 03690, San Vicente del Raspeig, Spain
| | - Gema Esquiva
- Department of Physiology, Genetics and Microbiology, University of Alicante, 03690, San Vicente del Raspeig, Spain
| | - Thomas G Beach
- Banner Sun Health Research Institute, Sun City, AZ, 85351, USA
| | - Geidy E Serrano
- Banner Sun Health Research Institute, Sun City, AZ, 85351, USA
| | | | - Pedro Lax
- Department of Physiology, Genetics and Microbiology, University of Alicante, 03690, San Vicente del Raspeig, Spain
| | - Nicolás Cuenca
- Department of Physiology, Genetics and Microbiology, University of Alicante, 03690, San Vicente del Raspeig, Spain.
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211
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Cruz CF, Piemonte MEP, Okai-Nobrega LA, Okamoto E, Fortaleza ACDS, Mancini M, Horak FB, Barela JA. Parkinson's disease does not alter automatic visual-motor coupling in postural control. Neurosci Lett 2018; 686:47-52. [PMID: 30193795 DOI: 10.1016/j.neulet.2018.08.050] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 07/25/2018] [Accepted: 08/31/2018] [Indexed: 11/26/2022]
Abstract
This study examined the coupling between visual information and body sway in patients with Parkinson's disease (PD) compared with healthy controls. Postural control performance was compared between 14 patients with PD (age: 69.6 ± 8.8 years - stages 1-3 of the Hoehn and Yahr scale) and 14 healthy control participants (age: 68.6 ± 3.0 years). Participants stood upright in a moving room that remained motionless or continuously oscillated in the anterior-posterior direction. Ten trials were performed in the following conditions: no movement of the room (1 trial) and with the room moving at frequencies of 0.1, 0.17, and 0.5 Hz (3 trials each frequency). Body sway and moving room displacement were recorded. The results indicated that patients with PD displayed larger body sway magnitude in the stationary room condition. Body sway of patients with PD was induced by visual manipulation in all three visual stimulus frequencies, but body sway of patients with PD was less coherent compared to that of the control participants. However, no difference was observed in the visual-body sway coupling structure. These results indicate that patients with PD can unconsciously couple body sway to visual information in order to control postural sway in a similar manner to healthy participants with intact visual-motor coupling for posture control. However, this coupling is marked by greater variability, indicating that people with PD have a motor system with greater inherent noise leading to a more varied behavior.
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Affiliation(s)
- Caio Ferraz Cruz
- Institute of Physical Activity and Sport Sciences, Cruzeiro do Sul University, São Paulo, SP, Brazil; School of Arts, Sciences and Humanities, University of São Paulo, São Paulo, SP, Brazil
| | - Maria Elisa Pimentel Piemonte
- Faculty of Medicine, University of São Paulo, São Paulo, SP, Brazil; Brazilian Parkinson Association, São Paulo, SP, Brazil
| | - Líria Akie Okai-Nobrega
- School of Physical Education, Physiotherapy and Occupational Therapy, Federal University of Minas Gerais, Belo Horizonte, MG, Brazil
| | - Erika Okamoto
- Brazilian Parkinson Association, São Paulo, SP, Brazil
| | | | - Martina Mancini
- Portland Veterans Affairs Health Care Service and Oregon Health and Sciences University, Portland, OR, USA
| | - Fay Bahling Horak
- Portland Veterans Affairs Health Care Service and Oregon Health and Sciences University, Portland, OR, USA
| | - José Angelo Barela
- Institute of Biosciences, São Paulo State University, Rio Claro, SP, Brazil.
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212
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Hunt D, Stuart S, Nell J, Hausdorff JM, Galna B, Rochester L, Alcock L. Do people with Parkinson’s disease look at task relevant stimuli when walking? An exploration of eye movements. Behav Brain Res 2018; 348:82-89. [DOI: 10.1016/j.bbr.2018.03.003] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2017] [Revised: 03/01/2018] [Accepted: 03/02/2018] [Indexed: 01/27/2023]
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213
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Pelak VS, Berman BD. Transient Daily Episodes of Vision Loss Due to Parkinson's Disease. Neuroophthalmology 2018; 43:260-264. [PMID: 31528193 DOI: 10.1080/01658107.2018.1494202] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2018] [Revised: 06/20/2018] [Accepted: 06/25/2018] [Indexed: 10/28/2022] Open
Abstract
Visual complaints are common in Parkinson's disease (PD), but transient visual loss has not previously been defined as a feature of parkinsonian-related disease. We report a patient with recurrent daily episodes of transient and disabling visual loss due to PD-related non-motor fluctuation. During his visit, he experienced one such episode, which allowed for close observation and examination during and after the visual loss. Implications for localization of the visual loss are reviewed in the context of visual pathway disturbances in PD.
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Affiliation(s)
- Victoria S Pelak
- Department of Neurology, University of Colorado School of Medicine, Aurora, Colorado, USA.,Department of Ophthalmology, University of Colorado School of Medicine, Aurora, Colorado, USA
| | - Brian D Berman
- Department of Neurology, University of Colorado School of Medicine, Aurora, Colorado, USA
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214
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de Castro Dos Santos D, Barbosa ER, Cury RG. Association of Optic Pathways and Brain Structure With Deep Brain Stimulation of the Nucleus Basalis of Meynert for Parkinson Disease Dementia. JAMA Neurol 2018; 75:896. [PMID: 29799928 DOI: 10.1001/jamaneurol.2018.1066] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022]
Affiliation(s)
| | - Egberto Reis Barbosa
- Movement Disorders Unit, Department of Neurology, University of São Paulo, São Paulo, Brazil
| | - Rubens Gisbert Cury
- Movement Disorders Unit, Department of Neurology, University of São Paulo, São Paulo, Brazil
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215
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Abstract
PURPOSE OF REVIEW This article discusses visual disorders in both Parkinson disease (PD) and other Parkinsonian disorders. It is organized largely by the anatomical site of pathology and emphasizes practical treatments. Targeted treatment options include medications, surgery, occupational, and physical therapies as well as optical aids. RECENT FINDINGS The causes of visual complaints in Parkinson disease and other similar disorders are being more clearly identified. A new medication approved specifically to treat hallucinations in PD now is available. There is increased understanding of the important role that an ophthalmologist can play in the care of these patients. Finally, research and therapeutic development are unmet needs in accessing and treating visual complaints in PD and Parkinsonian disorders. A better understanding of Parkinson-related visual complaints and of available treatment options is important to optimize patient safety and quality of life. Vision impairment leads to difficulties in many common activities including reading, ambulating, and driving. Falls and injuries, made more likely because of impaired vision, result in an early loss of independence. Awareness of the problem, patient education, ophthalmologic care, selected therapeutics, physical therapy, and occupational therapy are crucial to maximizing quality of life in these patients.
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Affiliation(s)
- Joseph Savitt
- Department of Neurology, University of Maryland School of Medicine, 110 South Paca Street 3rd Floor, Baltimore, MD, 21201, USA.
| | - Michaela Mathews
- Department of Ophthalmology, University of Maryland School of Medicine, Baltimore, MD, USA
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216
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Benvenutti R, Marcon M, Reis CG, Nery LR, Miguel C, Herrmann AP, Vianna MRM, Piato A. N-acetylcysteine protects against motor, optomotor and morphological deficits induced by 6-OHDA in zebrafish larvae. PeerJ 2018; 6:e4957. [PMID: 29868300 PMCID: PMC5985760 DOI: 10.7717/peerj.4957] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Accepted: 05/22/2018] [Indexed: 12/13/2022] Open
Abstract
Background Parkinson's disease (PD) is the second most common neurodegenerative disorder. In addition to its highly debilitating motor symptoms, non-motor symptoms may precede their motor counterparts by many years, which may characterize a prodromal phase of PD. A potential pharmacological strategy is to introduce neuroprotective agents at an earlier stage in order to prevent further neuronal death. N-acetylcysteine (NAC) has been used against paracetamol overdose hepatotoxicity by restoring hepatic concentrations of glutathione (GSH), and as a mucolytic in chronic obstructive pulmonary disease by reducing disulfide bonds in mucoproteins. It has been shown to be safe for humans at high doses. More recently, several studies have evidenced that NAC has a multifaceted mechanism of action, presenting indirect antioxidant effect by acting as a GSH precursor, besides its anti-inflammatory and neurotrophic effects. Moreover, NAC modulates glutamate release through activation of the cystine-glutamate antiporter in extra-synaptic astrocytes. Its therapeutic benefits have been demonstrated in clinical trials for several neuropsychiatric conditions but has not been tested in PD models yet. Methods In this study, we evaluated the potential of NAC to prevent the damage induced by 6-hydroxydopamine (6-OHDA) on motor, optomotor and morphological parameters in a PD model in larval zebrafish. Results NAC was able to prevent the motor deficits (total distance, mean speed, maximum acceleration, absolute turn angle and immobility time), optomotor response impairment and morphological alterations (total length and head length) caused by exposure to 6-OHDA, which reinforce and broaden the relevance of its neuroprotective effects. Discussion NAC acts in different targets relevant to PD pathophysiology. Further studies and clinical trials are needed to assess this agent as a candidate for prevention and adjunctive treatment of PD.
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Affiliation(s)
- Radharani Benvenutti
- Programa de Pós-graduação em Neurociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Matheus Marcon
- Programa de Pós-graduação em Neurociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Carlos G Reis
- Programa de Pós-graduação em Neurociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Laura R Nery
- Programa de Pós-graduação em Biologia Celular e Molecular, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Camila Miguel
- Programa de Pós-graduação em Zoologia, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Ana P Herrmann
- Programa de Pós-graduação em Farmacologia e Terapêutica, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Monica R M Vianna
- Programa de Pós-graduação em Biologia Celular e Molecular, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.,Programa de Pós-graduação em Zoologia, Pontifícia Universidade Católica do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
| | - Angelo Piato
- Programa de Pós-graduação em Neurociências, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil.,Programa de Pós-graduação em Farmacologia e Terapêutica, Universidade Federal do Rio Grande do Sul, Porto Alegre, Rio Grande do Sul, Brazil
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217
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Sensitivity and Specificity of the ECAS in Parkinson's Disease and Progressive Supranuclear Palsy. PARKINSONS DISEASE 2018; 2018:2426012. [PMID: 29862010 PMCID: PMC5971325 DOI: 10.1155/2018/2426012] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 04/19/2018] [Indexed: 12/11/2022]
Abstract
Disentangling Parkinson's disease (PD) and progressive supranuclear palsy (PSP) may be a diagnostic challenge. Cognitive signs may be useful, but existing screens are often insufficiently sensitive or unsuitable for assessing people with motor disorders. We investigated whether the newly developed ECAS, designed to be used with people with even severe motor disability, was sensitive to the cognitive impairment seen in PD and PSP and able to distinguish between these two disorders. Thirty patients with PD, 11 patients with PSP, and 40 healthy controls were assessed using the ECAS, as well as an extensive neuropsychological assessment. The ECAS detected cognitive impairment in 30% of the PD patients, all of whom fulfilled the diagnostic criteria for mild cognitive impairment. The ECAS was also able to detect cognitive impairment in PSP patients, with 81.8% of patients performing in the impaired range. The ECAS total score distinguished between the patients with PSP and healthy controls with high sensitivity (91.0) and specificity (86.8). Importantly, the ECAS was also able to distinguish between the two syndromes, with the measures of verbal fluency offering high sensitivity (82.0) and specificity (80.0). In sum, the ECAS is a quick, simple, and inexpensive test that can be used to support the differential diagnosis of PSP.
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218
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O'Regan G, deSouza RM, Balestrino R, Schapira AH. Glucocerebrosidase Mutations in Parkinson Disease. JOURNAL OF PARKINSONS DISEASE 2018; 7:411-422. [PMID: 28598856 DOI: 10.3233/jpd-171092] [Citation(s) in RCA: 87] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Following the discovery of a higher than expected incidence of Parkinson Disease (PD) in Gaucher disease, a lysosomal storage disorder, mutations in the glucocerebrocidase (GBA) gene, which encodes a lysosomal enzyme involved in sphingolipid degradation were explored in the context of idiopathic PD. GBA mutations are now known to be the single largest risk factor for development of idiopathic PD. Clinically, on imaging and pharmacologically, GBA PD is almost identical to idiopathic PD, other than certain features that can be identified in the specialist research setting but not in routine clinical practice. In patients with a known GBA mutation, it is possible to monitor for prodromal signs of PD. The clinical similarity with idiopathic PD and the chance to identify PD at a pre-clinical stage provides a unique opportunity to research therapeutic options for early PD, before major irreversible neurodegeneration occurs. However, to date, the molecular mechanisms which lead to this increased PD risk in GBA mutation carriers are not fully elucidated. Experimental models to define the molecular mechanisms and test therapeutic options include cell culture, transgenic mice and other in vivo models amenable to genetic manipulation, such as drosophilia. Some key pathological pathways of interest in the context of GBA mutations include alpha synuclein aggregation, lysosomal-autophagy axis changes and endoplasmic reticulum stress. Therapeutic agents that exploit these pathways are being developed and include the small molecule chaperone Ambroxol. This review aims to summarise the main features of GBA-PD and provide insights into the pathological relevance of GBA mutations on molecular pathways and the therapeutic implications for PD resulting from investigation of the role of GBA in PD.
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Affiliation(s)
- Grace O'Regan
- Department of Clinical Neurosciences, UCL Institute of Neurology, Royal Free Campus, London, UK
| | - Ruth-Mary deSouza
- Department of Clinical Neurosciences, UCL Institute of Neurology, Royal Free Campus, London, UK
| | | | - Anthony H Schapira
- Department of Clinical Neurosciences, UCL Institute of Neurology, Royal Free Campus, London, UK
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219
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Himmelberg MM, West RJH, Elliott CJH, Wade AR. Abnormal visual gain control and excitotoxicity in early-onset Parkinson's disease Drosophila models. J Neurophysiol 2018; 119:957-970. [PMID: 29142100 PMCID: PMC5899316 DOI: 10.1152/jn.00681.2017] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/15/2017] [Revised: 11/13/2017] [Accepted: 11/13/2017] [Indexed: 12/17/2022] Open
Abstract
The excitotoxic theory of Parkinson's disease (PD) hypothesizes that a pathophysiological degeneration of dopaminergic neurons stems from neural hyperactivity at early stages of disease, leading to mitochondrial stress and cell death. Recent research has harnessed the visual system of Drosophila PD models to probe this hypothesis. Here, we investigate whether abnormal visual sensitivity and excitotoxicity occur in early-onset PD (EOPD) Drosophila models DJ-1αΔ72, DJ-1βΔ 93, and PINK15. We used an electroretinogram to record steady-state visually evoked potentials driven by temporal contrast stimuli. At 1 day of age, all EOPD mutants had a twofold increase in response amplitudes compared with w̄ controls. Furthermore, we found that excitotoxicity occurs in older EOPD models after increased neural activity is triggered by visual stimulation. In an additional analysis, we used a linear discriminant analysis to test whether there were subtle variations in neural gain control that could be used to classify Drosophila into their correct age and genotype. The discriminant analysis was highly accurate, classifying Drosophila into their correct genotypic class at all age groups at 50-70% accuracy (20% chance baseline). Differences in cellular processes link to subtle alterations in neural network operation in young flies, all of which lead to the same pathogenic outcome. Our data are the first to quantify abnormal gain control and excitotoxicity in EOPD Drosophila mutants. We conclude that EOPD mutations may be linked to more sensitive neuronal signaling in prodromal animals that may cause the expression of PD symptomologies later in life. NEW & NOTEWORTHY Steady-state visually evoked potential response amplitudes to multivariate temporal contrast stimuli were recorded in early-onset PD Drosophila models. Our data indicate that abnormal gain control and a subsequent visual loss occur in these PD mutants, supporting a broader excitotoxicity hypothesis in genetic PD. Furthermore, linear discriminant analysis could accurately classify Drosophila into their correct genotype at different ages throughout their lifespan. Our results suggest increased neural signaling in prodromal PD patients.
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Affiliation(s)
- Marc M Himmelberg
- Department of Psychology, The University of York , York , United Kingdom
| | - Ryan J H West
- Department of Biology, The University of York , York , United Kingdom
| | | | - Alex R Wade
- Department of Psychology, The University of York , York , United Kingdom
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220
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Liu S, Chen S, Ren J, Li B, Qin B. Ghrelin protects retinal ganglion cells against rotenone via inhibiting apoptosis, restoring mitochondrial function, and activating AKT-mTOR signaling. Neuropeptides 2018; 67:63-70. [PMID: 29174113 DOI: 10.1016/j.npep.2017.11.007] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 07/02/2017] [Revised: 10/25/2017] [Accepted: 11/17/2017] [Indexed: 02/06/2023]
Abstract
Ghrelin, a 28-amino acid peptide hormone, has protective effects on neuronal cells. The present study aimed to examine the neuroprotective effects of ghrelin on the rat retinal ganglion cells in the rotenone-induced in vitro model of Parkinson's disease (PD). Cell viability and cell apoptosis were determined by MTT assay and flow cytometry, respectively. Mitochondrial functions were detected by mitochondrial complex I activity assay and mitochondrial membrane potential (MMP) assay. The mRNA and protein expression levels were determined by qRT-PCR and western blot, respectively. Rotenone significantly suppressed cell viability and increased cell apoptosis, also decreased the mitochondrial complex I activity as well as MMP in rat retinal ganglion cell line (RGC-5). Growth hormone secretagogue receptor (Ghsr) siRNA transfection significantly suppressed the expression of Ghsr in RGC-5 cells. Ghrelin treatment attenuated the effects of rotenone-induced changes in cell viability, cell apoptosis and mitochondrial functions in RGC-5 cells. Post-transcriptional suppression by Ghsr siRNA transfection and treatment with GHS-R antagonist, YIL781, both significantly attenuated the effects of ghrelin in RGC-5 cells. Rotenone decreased the protein levels of Bcl-2 and increased the protein levels of Bax, cleaved caspase-3 and cleaved caspase-9, and this effect was reversed by ghrelin treatment. Ghrelin also prevented the inhibitory effects of rotenone on the AKT-mTOR signaling. The effects of ghrelin on the rotenone-induced changes in apoptosis-related protein levels and AKT-mTOR signaling were attenuated by Ghsr siRNA transfection and treatment with YIL781 in the RGC-5 cells. In addition, both rapamycin and AKT inhibitor IV pre-treatment significantly attenuated the effects of ghrelin on rotenone-induced changes in cell viability and cell apoptosis. In conclusion, ghrelin by acting on the GSH-R to protect rat retinal ganglion cells against rotenone via inhibiting apoptosis and restore mitochondrial functions in RGC-5 cells, and this effect was partially associated with the AKT-mTOR signaling pathway in RGC-5 cells.
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Affiliation(s)
- Shenwen Liu
- Shenzhen Eye Hospital, Affiliated Shenzhen Eye Hospital of Jinan University, Joint College of Optometry, Shenzhen University, Shenzhen Key Laboratory of Ophthalmology, Shenzhen City, Guangdong Province, China
| | - Sheng Chen
- Shenzhen Eye Hospital, Affiliated Shenzhen Eye Hospital of Jinan University, Joint College of Optometry, Shenzhen University, Shenzhen Key Laboratory of Ophthalmology, Shenzhen City, Guangdong Province, China
| | - Jing Ren
- Shenzhen Eye Hospital, Affiliated Shenzhen Eye Hospital of Jinan University, Joint College of Optometry, Shenzhen University, Shenzhen Key Laboratory of Ophthalmology, Shenzhen City, Guangdong Province, China
| | - Baijun Li
- Shenzhen Eye Hospital, Affiliated Shenzhen Eye Hospital of Jinan University, Joint College of Optometry, Shenzhen University, Shenzhen Key Laboratory of Ophthalmology, Shenzhen City, Guangdong Province, China
| | - Bo Qin
- Shenzhen Eye Hospital, Affiliated Shenzhen Eye Hospital of Jinan University, Joint College of Optometry, Shenzhen University, Shenzhen Key Laboratory of Ophthalmology, Shenzhen City, Guangdong Province, China.
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Distinct manifestation of cognitive deficits associate with different resting-state network disruptions in non-demented patients with Parkinson’s disease. J Neurol 2018; 265:688-700. [DOI: 10.1007/s00415-018-8755-5] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2017] [Revised: 12/11/2017] [Accepted: 01/17/2018] [Indexed: 12/13/2022]
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Lee BY, Zhu XH, Woo MK, Adriany G, Schillak S, Chen W. Interleaved 31 P MRS imaging of human frontal and occipital lobes using dual RF coils in combination with single-channel transmitter-receiver and dynamic B 0 shimming. NMR IN BIOMEDICINE 2018; 31:10.1002/nbm.3842. [PMID: 29073724 PMCID: PMC5736151 DOI: 10.1002/nbm.3842] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/08/2017] [Revised: 09/10/2017] [Accepted: 09/14/2017] [Indexed: 06/01/2023]
Abstract
In vivo 31 P magnetic resonance spectroscopy (MRS) provides a unique tool for the non-invasive study of brain energy metabolism and mitochondrial function. The assessment of bioenergetic impairment in different brain regions is essential to understand the pathophysiology and progression of human brain diseases. This article presents a simple and effective approach which allows the interleaved measurement of 31 P spectra and imaging from two distinct human brain regions of interest with dynamic B0 shimming capability. A transistor-transistor logic controller was employed to actively switch the single-channel X-nuclear radiofrequency (RF) transmitter-receiver between two 31 P RF surface coils, enabling the interleaved acquisition of two 31 P free induction decays (FIDs) from human occipital and frontal lobes within the same repetition time. Linear gradients were incorporated into the RF pulse sequence to perform the first-order dynamic shimming to further improve spectral resolution. The overall results demonstrate that the approach provides a cost-effective and time-efficient solution for reliable 31 P MRS measurement of cerebral phosphate metabolites and adenosine triphosphate (ATP) metabolic fluxes from two human brain regions with high detection sensitivity and spectral quality at 7 T. The same design concept can be extended to acquire multiple spectra from more than two brain regions or can be employed for other magnetic resonance applications beyond the 31 P spin.
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Affiliation(s)
- Byeong-Yeul Lee
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota Medical School, Minneapolis, MN 55455
| | - Xiao-Hong Zhu
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota Medical School, Minneapolis, MN 55455
| | - Myung Kyun Woo
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota Medical School, Minneapolis, MN 55455
| | - Gregor Adriany
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota Medical School, Minneapolis, MN 55455
| | | | - Wei Chen
- Center for Magnetic Resonance Research, Department of Radiology, University of Minnesota Medical School, Minneapolis, MN 55455
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223
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Lees AJ. Advice for those trying to find a cure for the shaking palsy. Lancet Neurol 2018; 17:27-28. [DOI: 10.1016/s1474-4422(17)30430-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2017] [Accepted: 11/27/2017] [Indexed: 10/18/2022]
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224
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Garcia-Diaz AI, Segura B, Baggio HC, Marti MJ, Valldeoriola F, Compta Y, Bargallo N, Uribe C, Campabadal A, Abos A, Junque C. Structural Brain Correlations of Visuospatial and Visuoperceptual Tests in Parkinson's Disease. J Int Neuropsychol Soc 2018; 24:33-44. [PMID: 28714429 PMCID: PMC5851059 DOI: 10.1017/s1355617717000583] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2017] [Revised: 05/18/2017] [Accepted: 05/30/2017] [Indexed: 12/22/2022]
Abstract
BACKGROUND Diagnosis of mild cognitive impairment in Parkinson's disease (PD) is relevant because it is a marker for evolution to dementia. However, the selection of suitable tests to evaluate separate cognitive domains in mild cognitive impairment related to PD remains an open question. The current work aims to investigate the neuroanatomical correlates of several visuospatial/visuoperceptual tests using the same sample and a multimodal MRI approach. METHODS The study included 36 PD patients and 20 healthy subjects matched for age, sex, and education. The visuospatial/visuoperceptual tests selected were: Pentagon Copying Test (PCT), Judgment of Line Orientation Test (JLOT), Visual Form Discrimination Test (VFDT), Facial Recognition Test (FRT), Symbol Digit Modalities Test (SMDT), and clock copying task (CLOX2). FreeSurfer was used to assess cortical thickness, and tract-based spatial statistics was used for fractional anisotropy analysis. RESULTS Lower performance in the PCT, JLOT, and SDMT was associated with extensive cortical thickness reductions in lateral parietal and temporal regions. VFDT and CLOX2 did not show this common pattern and correlated with more limited medial occipito-temporal and occipito-parietal regions. Performance in all visuospatial/visuoperceptual tests correlated with fractional anisotropy in the corpus callosum. CONCLUSIONS Our findings show that JLOT, SDMT, and PCT, in addition to differentiating patients from controls, are suitable visuospatial/visuoperceptual tests to reflect cortical thinning in lateral temporo-parietal regions in PD patients. We did not observe the dissociation between dorsal and ventral streams that was expected according to the neuropsychological classification of visuospatial and visuoperceptual tests. (JINS, 2018, 24, 33-44).
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Affiliation(s)
- Anna Isabel Garcia-Diaz
- Department of Medicine, Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Catalonia, Spain
- Neuroscience Institute, University of Barcelona, Barcelona, Catalonia, Spain
| | - Barbara Segura
- Department of Medicine, Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Catalonia, Spain
- Neuroscience Institute, University of Barcelona, Barcelona, Catalonia, Spain
| | - Hugo Cesar Baggio
- Department of Medicine, Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Catalonia, Spain
- Neuroscience Institute, University of Barcelona, Barcelona, Catalonia, Spain
| | - Maria Jose Marti
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Catalonia, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Hospital Clínic de Barcelona, Barcelona, Catalonia, Spain
- Movement Disorders Unit, Neurology Service, Hospital Clínic de Barcelona, Barcelona, Catalonia, Spain
| | - Francesc Valldeoriola
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Catalonia, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Hospital Clínic de Barcelona, Barcelona, Catalonia, Spain
- Movement Disorders Unit, Neurology Service, Hospital Clínic de Barcelona, Barcelona, Catalonia, Spain
| | - Yaroslau Compta
- Neuroscience Institute, University of Barcelona, Barcelona, Catalonia, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Catalonia, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Hospital Clínic de Barcelona, Barcelona, Catalonia, Spain
- Movement Disorders Unit, Neurology Service, Hospital Clínic de Barcelona, Barcelona, Catalonia, Spain
| | - Nuria Bargallo
- Neuroscience Institute, University of Barcelona, Barcelona, Catalonia, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Catalonia, Spain
- Centre de Diagnòstic per la Imatge, Hospital Clínic, Barcelona, Catalonia, Spain
| | - Carme Uribe
- Department of Medicine, Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Catalonia, Spain
- Neuroscience Institute, University of Barcelona, Barcelona, Catalonia, Spain
| | - Anna Campabadal
- Department of Medicine, Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Catalonia, Spain
- Neuroscience Institute, University of Barcelona, Barcelona, Catalonia, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Catalonia, Spain
| | - Alexandra Abos
- Department of Medicine, Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Catalonia, Spain
- Neuroscience Institute, University of Barcelona, Barcelona, Catalonia, Spain
| | - Carme Junque
- Department of Medicine, Faculty of Medicine and Health Science, University of Barcelona, Barcelona, Catalonia, Spain
- Neuroscience Institute, University of Barcelona, Barcelona, Catalonia, Spain
- Institut d’Investigacions Biomèdiques August Pi i Sunyer (IDIBAPS), Barcelona, Catalonia, Spain
- Centro de Investigación Biomédica en Red sobre Enfermedades Neurodegenerativas (CIBERNED), Hospital Clínic de Barcelona, Barcelona, Catalonia, Spain
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225
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La Morgia C, Di Vito L, Carelli V, Carbonelli M. Patterns of Retinal Ganglion Cell Damage in Neurodegenerative Disorders: Parvocellular vs Magnocellular Degeneration in Optical Coherence Tomography Studies. Front Neurol 2017; 8:710. [PMID: 29312131 PMCID: PMC5744067 DOI: 10.3389/fneur.2017.00710] [Citation(s) in RCA: 79] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/20/2017] [Accepted: 12/08/2017] [Indexed: 12/02/2022] Open
Abstract
Many neurodegenerative disorders, such as Parkinson’s disease (PD) and Alzheimer’s disease (AD), are characterized by loss of retinal ganglion cells (RGCs) as part of the neurodegenerative process. Optical coherence tomography (OCT) studies demonstrated variable degree of optic atrophy in these diseases. However, the pattern of degenerative changes affecting the optic nerve (ON) can be different. In particular, neurodegeneration is more evident for magnocellular RGCs in AD and multiple system atrophy with a pattern resembling glaucoma. Conversely, in PD and Huntington’s disease, the parvocellular RGCs are more vulnerable. This latter pattern closely resembles that of mitochondrial optic neuropathies, possibly pointing to similar pathogenic mechanisms. In this review, the currently available evidences on OCT findings in these neurodegenerative disorders are summarized with particular emphasis on the different pattern of RGC loss. The ON degeneration could become a validated biomarker of the disease, which may turn useful to follow natural history and possibly assess therapeutic efficacy.
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Affiliation(s)
- Chiara La Morgia
- IRCCS Institute of Neurological Sciences of Bologna, Bellaria Hospital, Bologna, Italy.,Neurology Unit, Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Lidia Di Vito
- IRCCS Institute of Neurological Sciences of Bologna, Bellaria Hospital, Bologna, Italy
| | - Valerio Carelli
- IRCCS Institute of Neurological Sciences of Bologna, Bellaria Hospital, Bologna, Italy.,Neurology Unit, Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | - Michele Carbonelli
- IRCCS Institute of Neurological Sciences of Bologna, Bellaria Hospital, Bologna, Italy
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226
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Kusne Y, Wolf AB, Townley K, Conway M, Peyman GA. Visual system manifestations of Alzheimer's disease. Acta Ophthalmol 2017; 95:e668-e676. [PMID: 27864881 DOI: 10.1111/aos.13319] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/27/2016] [Accepted: 10/07/2016] [Indexed: 12/13/2022]
Abstract
Alzheimer's disease (AD) is an increasingly common disease with massive personal and economic costs. While it has long been known that AD impacts the visual system, there has recently been an increased focus on understanding both pathophysiological mechanisms that may be shared between the eye and brain and how related biomarkers could be useful for AD diagnosis. Here, were review pertinent cellular and molecular mechanisms of AD pathophysiology, the presence of AD pathology in the visual system, associated functional changes, and potential development of diagnostic tools based on the visual system. Additionally, we discuss links between AD and visual disorders, including possible pathophysiological mechanisms and their relevance for improving our understanding of AD.
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Affiliation(s)
- Yael Kusne
- University of Arizona College of Medicine; Phoenix Arizona USA
| | - Andrew B. Wolf
- University of Colorado School of Medicine; Aurora Colorado USA
| | - Kate Townley
- University of Arizona College of Medicine; Phoenix Arizona USA
| | - Mandi Conway
- University of Arizona College of Medicine; Phoenix Arizona USA
- Arizona Retinal Specialists; Sun City Arizona USA
| | - Gholam A. Peyman
- University of Arizona College of Medicine; Phoenix Arizona USA
- Arizona Retinal Specialists; Sun City Arizona USA
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227
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Sha Z, Xia M, Lin Q, Cao M, Tang Y, Xu K, Song H, Wang Z, Wang F, Fox PT, Evans AC, He Y. Meta-Connectomic Analysis Reveals Commonly Disrupted Functional Architectures in Network Modules and Connectors across Brain Disorders. Cereb Cortex 2017; 28:4179-4194. [PMID: 29136110 DOI: 10.1093/cercor/bhx273] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Affiliation(s)
- Zhiqiang Sha
- National Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China
- Beijing Key Laboratory of Brain Imaging and Connectomics, Beijing Normal University, Beijing, China
- IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China
| | - Mingrui Xia
- National Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China
- Beijing Key Laboratory of Brain Imaging and Connectomics, Beijing Normal University, Beijing, China
- IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China
| | - Qixiang Lin
- National Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China
- Beijing Key Laboratory of Brain Imaging and Connectomics, Beijing Normal University, Beijing, China
- IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China
| | - Miao Cao
- National Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China
- Beijing Key Laboratory of Brain Imaging and Connectomics, Beijing Normal University, Beijing, China
- IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China
| | - Yanqing Tang
- Department of Psychiatry, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning, China
- Brain Function Research Section, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning, China
| | - Ke Xu
- Department of Radiology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning, China
| | - Haiqing Song
- Department of Neurology, Xuanwu Hospital of Capital Medical University, Beijing, China
| | - Zhiqun Wang
- Department of Radiology, Xuanwu Hospital of Capital Medical University, Beijing, China
- Department of Radiology, Dongfang Hospital, Beijing University of Chinese Medicine, Beijing, China
| | - Fei Wang
- Department of Psychiatry, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning, China
- Brain Function Research Section, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning, China
- Department of Radiology, The First Affiliated Hospital of China Medical University, Shenyang, Liaoning, China
| | - Peter T Fox
- Research Imaging Institute, University of Texas Health Science Center at San Antonio, TX, USA
- Department of Radiology, University of Texas Health Science Center at San Antonio, TX, USA
- South Texas Veterans Health Care System at San Antonio, TX, USA
- Shenzhen University School of Medicine, Shenzhen, China
| | - Alan C Evans
- McConnell Brain Imaging Center, Montreal Neurological Institute, Montreal, QC, Canada
| | - Yong He
- National Key Laboratory of Cognitive Neuroscience and Learning, Beijing Normal University, Beijing, China
- Beijing Key Laboratory of Brain Imaging and Connectomics, Beijing Normal University, Beijing, China
- IDG/McGovern Institute for Brain Research, Beijing Normal University, Beijing, China
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228
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Pretegiani E, Optican LM. Eye Movements in Parkinson's Disease and Inherited Parkinsonian Syndromes. Front Neurol 2017; 8:592. [PMID: 29170650 PMCID: PMC5684125 DOI: 10.3389/fneur.2017.00592] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 10/23/2017] [Indexed: 12/02/2022] Open
Abstract
Despite extensive research, the functions of the basal ganglia (BG) in movement control have not been fully understood. Eye movements, particularly saccades, are convenient indicators of BG function. Here, we review the main oculomotor findings reported in Parkinson’s disease (PD) and genetic parkinsonian syndromes. PD is a progressive, neurodegenerative disorder caused by dopaminergic cell loss within the substantia nigra pars compacta, resulting in depletion of striatal dopamine and subsequent increased inhibitory BG output from the internal globus pallidus and the substantia nigra pars reticulata. Eye movement abnormalities are common in PD: anomalies are more evident in voluntary than reflexive saccades in the initial stages, but visually guided saccades may also be involved at later stages. Saccadic hypometria (including abnormally fragmented saccades), reduced accuracy, and increased latency are among the most prominent deficits. PD patients show also unusually frequent and large square wave jerks and impaired inhibition of reflexive saccades when voluntary mirror saccades are required. Poor convergence ability and altered pursuit are common. Inherited parkinsonisms are a heterogeneous group of rare syndromes due to gene mutations causing symptoms resembling those of PD. Eye movement characteristics of some parkinsonisms have been studied. While sharing some PD features, each syndrome has a distinctive profile that could contribute to better define the clinical phenotype of parkinsonian disorders. Moreover, because the pathogenesis and the underlying neural circuit failure of inherited parkinsonisms are often well defined, they might offer a better prospect than idiopathic PD to understand the BG function.
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Affiliation(s)
- Elena Pretegiani
- Laboratory of Sensorimotor Research, National Eye Institute, NIH, Bethesda, MD, United States
| | - Lance M Optican
- Laboratory of Sensorimotor Research, National Eye Institute, NIH, Bethesda, MD, United States
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229
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Guan X, Zeng Q, Guo T, Wang J, Xuan M, Gu Q, Wang T, Huang P, Xu X, Zhang M. Disrupted Functional Connectivity of Basal Ganglia across Tremor-Dominant and Akinetic/Rigid-Dominant Parkinson's Disease. Front Aging Neurosci 2017; 9:360. [PMID: 29163141 PMCID: PMC5673841 DOI: 10.3389/fnagi.2017.00360] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2017] [Accepted: 10/20/2017] [Indexed: 11/23/2022] Open
Abstract
It is well known that disruption of basal ganglia function generates the motor symptoms in PD, however, these are presented in a heterogeneous manner; patients can be divided into tremor-dominant and akinesia/rigidity-dominant subtypes. To date, it is unknown if these differences in the motor symptoms could be explained by differences on the functional connectivity of basal ganglia with specific brain regions. In this study, we aimed to explore the alterations of the network-based and global functional connectivity linking to basal ganglia between the PD-TD and PD-AR patients. One hundred and six PD patients and 52 normal controls were recruited. According to the subscales of UPDRS motor scale, PD patients were divided into the PD-TD (n = 57) and PD-AR (n = 49) subtypes. We performed independent component analysis to identify basal ganglia network (BGN) involving connected brain regions having coactivation with basal ganglia. Eigenvector centrality mapping were processed and the eigenvector centrality in the subcortical component of BGN including the bilateral caudate nuclei, putamen, thalami and pallidum were extracted to measure the global connectivity. Compared with controls, whole PD patients or PD subtypes showed decreases of functional connectivity within the subcortical component of BGN, e.g., thalamus, pallidum and putamen. Compared with controls, decreased functional connectivity of precuneus and amygdala with basal ganglia was observed in the PD-TD while that of occipital lobule and precuneus was observed in the PD-AR. Compared with the PD-TD, significantly decreased functional connectivity between occipital lobule and cerebellum posterior lobule and basal ganglia was observed in the PD-AR, and such connectivity had positive correlations with tremor and negative correlations with akinesia/rigidity. We also observed enhanced global connectivity in the caudate nucleus and thalamus in the PD subtypes compared with controls. In conclusion, PD patients independent of motor subtypes consistently express similar alterations of functional connectivity within the subcortical component of BGN including network-based connectivity and global connectivity. Functional connectivity of cerebellum posterior lobule and occipital lobule with basal ganglia play important roles in the modulation of parkinsonian motor symptoms.
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Affiliation(s)
- Xiaojun Guan
- Department of Radiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Qiaoling Zeng
- Department of Radiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Tao Guo
- Department of Radiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Jiaqiu Wang
- Department of Neurology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Min Xuan
- Department of Radiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Quanquan Gu
- Department of Radiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Tao Wang
- Department of Radiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Peiyu Huang
- Department of Radiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Xiaojun Xu
- Department of Radiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
| | - Minming Zhang
- Department of Radiology, The Second Affiliated Hospital, Zhejiang University School of Medicine, Hangzhou, China
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230
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Weil RS, McColgan P, Schrag AE, Warren JD, Crutch SJ, Lees AJ, Morris HR. Reply: MRI findings of visual system alterations in Parkinson's disease. Brain 2017; 140:e70. [PMID: 29053804 DOI: 10.1093/brain/awx245] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Affiliation(s)
- Rimona S Weil
- Department of Molecular Neuroscience, UCL Institute of Neurology, UK.,Dementia Research Centre, UCL Institute of Neurology, UK
| | | | - Anette E Schrag
- Department of Clinical Neurosciences, Royal Free Campus UCL Institute of Neurology, UK
| | - Jason D Warren
- Dementia Research Centre, UCL Institute of Neurology, UK
| | | | - Andrew J Lees
- Department of Molecular Neuroscience, Reta Lila Weston Institute of Neurological Studies, UCL Institute of Neurology, UK
| | - Huw R Morris
- Department of Molecular Neuroscience, UCL Institute of Neurology, UK.,Department of Clinical Neurosciences, Royal Free Campus UCL Institute of Neurology, UK
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231
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Kim J, Criaud M, Cho SS, Díez-Cirarda M, Mihaescu A, Coakeley S, Ghadery C, Valli M, Jacobs MF, Houle S, Strafella AP. Abnormal intrinsic brain functional network dynamics in Parkinson's disease. Brain 2017; 140:2955-2967. [PMID: 29053835 PMCID: PMC5841202 DOI: 10.1093/brain/awx233] [Citation(s) in RCA: 232] [Impact Index Per Article: 33.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/17/2017] [Revised: 06/22/2017] [Accepted: 07/17/2017] [Indexed: 01/17/2023] Open
Abstract
See Nieuwhof and Helmich (doi:10.1093/brain/awx267 ) for a scientific commentary on this article . Parkinson’s disease is a neurodegenerative disorder characterized by nigrostriatal dopamine depletion. Previous studies measuring spontaneous brain activity using resting state functional magnetic resonance imaging have reported abnormal changes in broadly distributed whole-brain networks. Although resting state functional connectivity, estimating temporal correlations between brain regions, is measured with the assumption that intrinsic fluctuations throughout the scan are stable, dynamic changes of functional connectivity have recently been suggested to reflect aspects of functional capacity of neural systems, and thus may serve as biomarkers of disease. The present work is the first study to investigate the dynamic functional connectivity in patients with Parkinson’s disease, with a focus on the temporal properties of functional connectivity states as well as the variability of network topological organization using resting state functional magnetic resonance imaging. Thirty-one Parkinson’s disease patients and 23 healthy controls were studied using group spatial independent component analysis, a sliding windows approach, and graph-theory methods. The dynamic functional connectivity analyses suggested two discrete connectivity configurations: a more frequent, sparsely connected within-network state (State I) and a less frequent, more strongly interconnected between-network state (State II). In patients with Parkinson’s disease, the occurrence of the sparsely connected State I dropped by 12.62%, while the expression of the more strongly interconnected State II increased by the same amount. This was consistent with the altered temporal properties of the dynamic functional connectivity characterized by a shortening of the dwell time of State I and by a proportional increase of the dwell time pattern in State II. These changes are suggestive of a reduction in functional segregation among networks and are correlated with the clinical severity of Parkinson’s disease symptoms. Additionally, there was a higher variability in the network global efficiency, suggesting an abnormal global integration of the brain networks. The altered functional segregation and abnormal global integration in brain networks confirmed the vulnerability of functional connectivity networks in Parkinson’s disease.
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Affiliation(s)
- Jinhee Kim
- Morton and Gloria Shulman Movement Disorder Unit and E.J. Safra Parkinson Disease Program, Neurology Division, Department of Medicine, Toronto Western Hospital, University Health Network, University of Toronto, Ontario, M5G 2C4, Canada
- Research Imaging Centre, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, M5T 2S8, Canada
- Division of Brain, Imaging and Behaviour – Systems Neuroscience, Krembil Research Institute, University Health Network, University of Toronto, Ontario, M5T 2S8, Canada
| | - Marion Criaud
- Morton and Gloria Shulman Movement Disorder Unit and E.J. Safra Parkinson Disease Program, Neurology Division, Department of Medicine, Toronto Western Hospital, University Health Network, University of Toronto, Ontario, M5G 2C4, Canada
- Research Imaging Centre, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, M5T 2S8, Canada
- Division of Brain, Imaging and Behaviour – Systems Neuroscience, Krembil Research Institute, University Health Network, University of Toronto, Ontario, M5T 2S8, Canada
| | - Sang Soo Cho
- Morton and Gloria Shulman Movement Disorder Unit and E.J. Safra Parkinson Disease Program, Neurology Division, Department of Medicine, Toronto Western Hospital, University Health Network, University of Toronto, Ontario, M5G 2C4, Canada
- Research Imaging Centre, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, M5T 2S8, Canada
- Division of Brain, Imaging and Behaviour – Systems Neuroscience, Krembil Research Institute, University Health Network, University of Toronto, Ontario, M5T 2S8, Canada
| | - María Díez-Cirarda
- Morton and Gloria Shulman Movement Disorder Unit and E.J. Safra Parkinson Disease Program, Neurology Division, Department of Medicine, Toronto Western Hospital, University Health Network, University of Toronto, Ontario, M5G 2C4, Canada
- Research Imaging Centre, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, M5T 2S8, Canada
- Division of Brain, Imaging and Behaviour – Systems Neuroscience, Krembil Research Institute, University Health Network, University of Toronto, Ontario, M5T 2S8, Canada
| | - Alexander Mihaescu
- Morton and Gloria Shulman Movement Disorder Unit and E.J. Safra Parkinson Disease Program, Neurology Division, Department of Medicine, Toronto Western Hospital, University Health Network, University of Toronto, Ontario, M5G 2C4, Canada
- Research Imaging Centre, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, M5T 2S8, Canada
- Division of Brain, Imaging and Behaviour – Systems Neuroscience, Krembil Research Institute, University Health Network, University of Toronto, Ontario, M5T 2S8, Canada
| | - Sarah Coakeley
- Morton and Gloria Shulman Movement Disorder Unit and E.J. Safra Parkinson Disease Program, Neurology Division, Department of Medicine, Toronto Western Hospital, University Health Network, University of Toronto, Ontario, M5G 2C4, Canada
- Research Imaging Centre, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, M5T 2S8, Canada
- Division of Brain, Imaging and Behaviour – Systems Neuroscience, Krembil Research Institute, University Health Network, University of Toronto, Ontario, M5T 2S8, Canada
| | - Christine Ghadery
- Morton and Gloria Shulman Movement Disorder Unit and E.J. Safra Parkinson Disease Program, Neurology Division, Department of Medicine, Toronto Western Hospital, University Health Network, University of Toronto, Ontario, M5G 2C4, Canada
- Research Imaging Centre, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, M5T 2S8, Canada
- Division of Brain, Imaging and Behaviour – Systems Neuroscience, Krembil Research Institute, University Health Network, University of Toronto, Ontario, M5T 2S8, Canada
| | - Mikaeel Valli
- Morton and Gloria Shulman Movement Disorder Unit and E.J. Safra Parkinson Disease Program, Neurology Division, Department of Medicine, Toronto Western Hospital, University Health Network, University of Toronto, Ontario, M5G 2C4, Canada
- Research Imaging Centre, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, M5T 2S8, Canada
- Division of Brain, Imaging and Behaviour – Systems Neuroscience, Krembil Research Institute, University Health Network, University of Toronto, Ontario, M5T 2S8, Canada
| | - Mark F Jacobs
- Morton and Gloria Shulman Movement Disorder Unit and E.J. Safra Parkinson Disease Program, Neurology Division, Department of Medicine, Toronto Western Hospital, University Health Network, University of Toronto, Ontario, M5G 2C4, Canada
- Research Imaging Centre, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, M5T 2S8, Canada
- Division of Brain, Imaging and Behaviour – Systems Neuroscience, Krembil Research Institute, University Health Network, University of Toronto, Ontario, M5T 2S8, Canada
| | - Sylvain Houle
- Research Imaging Centre, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, M5T 2S8, Canada
| | - Antonio P Strafella
- Morton and Gloria Shulman Movement Disorder Unit and E.J. Safra Parkinson Disease Program, Neurology Division, Department of Medicine, Toronto Western Hospital, University Health Network, University of Toronto, Ontario, M5G 2C4, Canada
- Research Imaging Centre, Campbell Family Mental Health Research Institute, Centre for Addiction and Mental Health, University of Toronto, Toronto, Ontario, M5T 2S8, Canada
- Division of Brain, Imaging and Behaviour – Systems Neuroscience, Krembil Research Institute, University Health Network, University of Toronto, Ontario, M5T 2S8, Canada
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Arrigo A, Calamuneri A, Mormina E, Aragona P, Gaeta M, Quartarone A. MRI findings of visual system alterations in Parkinson’s disease. Brain 2017; 140:e69. [DOI: 10.1093/brain/awx244] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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233
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Leinonen H, Tanila H. Vision in laboratory rodents-Tools to measure it and implications for behavioral research. Behav Brain Res 2017; 352:172-182. [PMID: 28760697 DOI: 10.1016/j.bbr.2017.07.040] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 07/17/2017] [Accepted: 07/27/2017] [Indexed: 02/09/2023]
Abstract
Mice and rats are nocturnal mammals and their vision is specialized for detection of motion and contrast in dim light conditions. These species possess a large proportion of UV-sensitive cones in their retinas and the majority of their optic nerve axons target superior colliculus rather than visual cortex. Therefore, it was a widely held belief that laboratory rodents hardly utilize vision during day-time behavior. This dogma is being questioned as accumulating evidence suggests that laboratory rodents are able to perform complex visual functions, such as perceiving subjective contours, and that declined vision may affect their performance in many behavioral tasks. For instance, genetic engineering may have unexpected consequences on vision as mouse models of Alzheimer's and Huntington's diseases have declined visual function. Rodent vision can be tested in numerous ways using operant training or reflex-based behavioral tasks, or alternatively using electrophysiological recordings. In this article, we will first provide a summary of visual system and explain its characteristics unique to rodents. Then, we present well-established techniques to test rodent vision, with an emphasis on pattern vision: visual water test, optomotor reflex test, pattern electroretinography and pattern visual evoked potentials. Finally, we highlight the importance of visual phenotyping in rodents. As the number of genetically engineered rodent models and volume of behavioral testing increase simultaneously, the possibility of visual dysfunctions needs to be addressed. Neglect in this matter potentially leads to crude biases in the field of neuroscience and beyond.
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Affiliation(s)
- Henri Leinonen
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, Neulaniementie 2, 70211 Kuopio, Finland.
| | - Heikki Tanila
- A.I. Virtanen Institute for Molecular Sciences, University of Eastern Finland, P.O. Box 1627, Neulaniementie 2, 70211 Kuopio, Finland
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234
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McLean G, Hindle JV, Guthrie B, Mercer SW. Co-morbidity and polypharmacy in Parkinson's disease: insights from a large Scottish primary care database. BMC Neurol 2017; 17:126. [PMID: 28666413 PMCID: PMC5493890 DOI: 10.1186/s12883-017-0904-4] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2017] [Accepted: 06/22/2017] [Indexed: 11/10/2022] Open
Abstract
Background Parkinson’s disease is complicated by comorbidity and polypharmacy, but the extent and patterns of these are unclear. We describe comorbidity and polypharmacy in patients with and without Parkinson’s disease across 31 other physical, and seven mental health conditions. Methods We analysed primary health-care data on 510,502 adults aged 55 and over. We generated standardised prevalence rates by age-groups, gender, and neighbourhood deprivation, then calculated age, sex and deprivation adjusted odds ratios (OR) and 95% confidence intervals (95% CI) for those with PD compared to those without, for the prevalence, and number of conditions. Results Two thousand six hundred forty (0.5%) had Parkinson’s disease, of whom only 7.4% had no other conditions compared with 22.9% of controls (adjusted OR [aOR] 0.43, 95% 0.38–0.49). The Parkinson’s group had more conditions, with the biggest difference found for seven or more conditions (PD 12.1% vs. controls 3.9%; aOR 2.08 95% CI 1.84–2.35). 12 of the 31 physical conditions and five of the seven mental health conditions were significantly more prevalent in the PD group. 44.5% with Parkinson’s disease were on five to nine repeat prescriptions compared to 24.5% of controls (aOR 1.40; 95% CI 1.28 to 1.53) and 19.2% on ten or more compared to 6.2% of controls (aOR 1.90; 95% CI 1.68 to 2.15). Conclusions Parkinson’s disease is associated with substantial physical and mental co-morbidity. Polypharmacy is also a significant issue due to the complex nature of the disease and associated treatments.
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Affiliation(s)
- Gary McLean
- General Practice and Primary Care, Institute of Health and Wellbeing, University of Glasgow, Glasgow, G12 9LX, UK
| | | | - Bruce Guthrie
- Population Health Sciences Division, University of Dundee, Mackenzie Building, Kirsty Semple Way, Dundee, DD2 4BF, UK
| | - Stewart W Mercer
- General Practice and Primary Care, Institute of Health and Wellbeing, University of Glasgow, Glasgow, G12 9LX, UK.
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235
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Jellinger KA. Neuropathology of Nonmotor Symptoms of Parkinson's Disease. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2017; 133:13-62. [PMID: 28802920 DOI: 10.1016/bs.irn.2017.05.005] [Citation(s) in RCA: 31] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
Parkinson's disease (PD), a multiorgan neurodegenerative disorder associated with α-synuclein deposits throughout the nervous system and many organs, is clinically characterized by motor and nonmotor features, many of the latter antedating motor dysfunctions by 20 or more years. The causes of the nonmotor manifestations such as olfactory, autonomic, sensory, neuropsychiatric, visuospatial, sleep, and other disorders are unlikely to be related to single lesions. They are mediated by the involvement of both dopaminergic and nondopaminergic systems, and diverse structures outside the nigrostriatal system that is mainly responsible for the motor features of PD. The nonmotor alterations appear in early/prodromal stages of the disease and its further progression, suggesting a topographical and chronological spread of the lesions. This lends further support for the notion that PD is a multiorgan proteinopathy, although the exact relationship between presymptomatic and later developing nonmotor features of PD and neuropathology awaits further elucidation.
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Abstract
This chapter describes the visual problems likely to be encountered in Parkinson's disease (PD) and whether such signs are useful in differentiating the parkinsonian syndromes. Visual dysfunction in PD may involve visual acuity, contrast sensitivity, color discrimination, pupil reactivity, saccadic and pursuit eye movements, motion perception, visual fields, and visual processing speeds. In addition, disturbance of visuospatial orientation, facial recognition problems, rapid eye movement (REM) sleep behavior disorder, and chronic visual hallucinations may be present. Problems affecting pupil reactivity, stereopsis, pursuit eye movement, and visuomotor adaptation, when accompanied by REM sleep behavior disorder, could be early features of PD. Dementia associated with PD is associated with enhanced eye movement problems, visuospatial deficits, and visual hallucinations. Visual dysfunction may be a useful diagnostic feature in differentiating PD from other parkinsonian symptoms, visual hallucinations, visuospatial dysfunction, and variation in saccadic eye movement problems being particularly useful discriminating features.
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237
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Stuart S, Galna B, Delicato LS, Lord S, Rochester L. Direct and indirect effects of attention and visual function on gait impairment in Parkinson's disease: influence of task and turning. Eur J Neurosci 2017; 46:1703-1716. [PMID: 28444834 DOI: 10.1111/ejn.13589] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 04/11/2017] [Accepted: 04/12/2017] [Indexed: 12/26/2022]
Abstract
Gait impairment is a core feature of Parkinson's disease (PD) which has been linked to cognitive and visual deficits, but interactions between these features are poorly understood. Monitoring saccades allows investigation of real-time cognitive and visual processes and their impact on gait when walking. This study explored: (i) saccade frequency when walking under different attentional manipulations of turning and dual-task; and (ii) direct and indirect relationships between saccades, gait impairment, vision and attention. Saccade frequency (number of fast eye movements per-second) was measured during gait in 60 PD and 40 age-matched control participants using a mobile eye-tracker. Saccade frequency was significantly reduced in PD compared to controls during all conditions. However, saccade frequency increased with a turn and decreased under dual-task for both groups. Poorer attention directly related to saccade frequency, visual function and gait impairment in PD, but not controls. Saccade frequency did not directly relate to gait in PD, but did in controls. Instead, saccade frequency and visual function deficit indirectly impacted gait impairment in PD, which was underpinned by their relationship with attention. In conclusion, our results suggest a vital role for attention with direct and indirect influences on gait impairment in PD. Attention directly impacted saccade frequency, visual function and gait impairment in PD, with connotations for falls. It also underpinned indirect impact of visual and saccadic impairment on gait. Attention therefore represents a key therapeutic target that should be considered in future research.
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Affiliation(s)
- Samuel Stuart
- Clinical Ageing Research Unit, Institute of Neuroscience, Newcastle University Institute of Ageing, Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne, NE4 5PL, UK.,Newcastle upon Tyne Hospitals NHS foundation trust, Newcastle upon Tyne, UK
| | - Brook Galna
- Clinical Ageing Research Unit, Institute of Neuroscience, Newcastle University Institute of Ageing, Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne, NE4 5PL, UK
| | - Louise S Delicato
- Clinical Ageing Research Unit, Institute of Neuroscience, Newcastle University Institute of Ageing, Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne, NE4 5PL, UK.,School of Psychology, University of Sunderland, Sunderland, UK
| | - Sue Lord
- Clinical Ageing Research Unit, Institute of Neuroscience, Newcastle University Institute of Ageing, Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne, NE4 5PL, UK
| | - Lynn Rochester
- Clinical Ageing Research Unit, Institute of Neuroscience, Newcastle University Institute of Ageing, Newcastle University, Campus for Ageing and Vitality, Newcastle upon Tyne, NE4 5PL, UK.,Newcastle upon Tyne Hospitals NHS foundation trust, Newcastle upon Tyne, UK
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La Morgia C, Ross-Cisneros FN, Sadun AA, Carelli V. Retinal Ganglion Cells and Circadian Rhythms in Alzheimer's Disease, Parkinson's Disease, and Beyond. Front Neurol 2017; 8:162. [PMID: 28522986 PMCID: PMC5415575 DOI: 10.3389/fneur.2017.00162] [Citation(s) in RCA: 74] [Impact Index Per Article: 10.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2017] [Accepted: 04/07/2017] [Indexed: 12/25/2022] Open
Abstract
There is increasing awareness on the role played by circadian rhythm abnormalities in neurodegenerative disorders such as Alzheimer’s disease (AD) and Parkinson’s disease (PD). The characterization of the circadian dysfunction parallels the mounting evidence that the hallmarks of neurodegeneration also affect the retina and frequently lead to loss of retinal ganglion cells (RGCs) and to different degrees of optic neuropathy. In the RGC population, there is the subgroup of cells intrinsically photosensitive and expressing the photopigment melanopsin [melanopsin-containing retinal ganglion cells (mRGCs)], which are now well known to drive the entrainment of circadian rhythms to the light–dark cycles. Thus, the correlation between the pathological changes affecting the retina and mRGCs with the circadian imbalance in these neurodegenerative diseases is now clearly emerging, pointing to the possibility that these patients might be amenable to and benefit from light therapy. Currently, this connection is better established for AD and PD, but the same scenario may apply to other neurodegenerative disorders, such as Huntington’s disease. This review highlights similarities and differences in the retinal/circadian rhythm axis in these neurodegenerative diseases posing a working frame for future studies.
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Affiliation(s)
- Chiara La Morgia
- IRCCS Institute of Neurological Sciences of Bologna, Bellaria Hospital, Bologna, Italy.,Neurology Unit, Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
| | | | - Alfredo A Sadun
- Doheny Eye Institute, Los Angeles, CA, USA.,Department of Ophthalmology, David Geffen School of Medicine at University of California Los Angeles, Los Angeles, CA, USA
| | - Valerio Carelli
- IRCCS Institute of Neurological Sciences of Bologna, Bellaria Hospital, Bologna, Italy.,Neurology Unit, Department of Biomedical and Neuromotor Sciences, University of Bologna, Bologna, Italy
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Visual Hallucinations Are Characterized by Impaired Sensory Evidence Accumulation: Insights From Hierarchical Drift Diffusion Modeling in Parkinson's Disease. BIOLOGICAL PSYCHIATRY: COGNITIVE NEUROSCIENCE AND NEUROIMAGING 2017; 2:680-688. [PMID: 29560902 DOI: 10.1016/j.bpsc.2017.04.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/25/2017] [Revised: 03/30/2017] [Accepted: 04/23/2017] [Indexed: 01/16/2023]
Abstract
BACKGROUND Models of hallucinations emphasize imbalance between sensory input and top-down influences over perception, as false perceptual inference can arise when top-down predictions are afforded too much precision (certainty) relative to sensory evidence. Visual hallucinations in Parkinson's disease (PD) are associated with lower-level visual and attentional impairments, accompanied by overactivity in higher-order association brain networks. PD therefore provides an attractive framework to explore contributions of bottom-up versus top-down disturbances in hallucinations. METHODS We characterized sensory processing during perceptual decision making in patients with PD with (n = 20) and without (n = 25) visual hallucinations and control subjects (n = 12), by fitting a hierarchical drift diffusion model to an attentional task. The hierarchical drift diffusion model uses Bayesian estimates to decompose task performance into parameters reflecting drift rates of evidence accumulation, decision thresholds, and nondecision time. RESULTS We observed slower drift rates in patients with hallucinations, which were less sensitive to changes in task demand. In contrast, wider decision boundaries and shorter nondecision times relative to control subjects were found in patients with PD regardless of hallucinator status. Inefficient and less flexible sensory evidence accumulation emerges as a unique feature of PD hallucinators. CONCLUSIONS We integrate these results with evidence accumulation and predictive coding models of hallucinations, suggesting that in PD sensory evidence is less informative and may therefore be down-weighted, resulting in overreliance on top-down influences. Considering impaired drift rates as an approximation of reduced sensory precision, our findings provide a novel computational framework to specify impairments in sensory processing that contribute to development of visual hallucinations.
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Abstract
Dementia syndromes associated with Lewy bodies are subdivided into dementia with Lewy bodies (DLB), an underdiagnosed cause of dementia in the elderly, and Parkinson disease with dementia (PDD), cognitive impairment appearing in people diagnosed with Parkinson disease. Their neuropathologic substrates are the widespread distribution of aggregates of the protein α-synuclein in neurons in cortical brain regions, accompanied by variable Alzheimer pathology. Clinical features of DLB and PDD include distinctive changes in cognition, behavior, movement, sleep, and autonomic function. Diagnostic criteria for DLB and PDD incorporate these features. Current treatment options for DLB and PDD are symptomatic.
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Affiliation(s)
- Douglas Galasko
- Department of Neurosciences, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0948, USA.
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Orlosky J, Itoh Y, Ranchet M, Kiyokawa K, Morgan J, Devos H. Emulation of Physician Tasks in Eye-Tracked Virtual Reality for Remote Diagnosis of Neurodegenerative Disease. IEEE TRANSACTIONS ON VISUALIZATION AND COMPUTER GRAPHICS 2017; 23:1302-1311. [PMID: 28129166 DOI: 10.1109/tvcg.2017.2657018] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
For neurodegenerative conditions like Parkinson's disease, early and accurate diagnosis is still a difficult task. Evaluations can be time consuming, patients must often travel to metropolitan areas or different cities to see experts, and misdiagnosis can result in improper treatment. To date, only a handful of assistive or remote methods exist to help physicians evaluate patients with suspected neurological disease in a convenient and consistent way. In this paper, we present a low-cost VR interface designed to support evaluation and diagnosis of neurodegenerative disease and test its use in a clinical setting. Using a commercially available VR display with an infrared camera integrated into the lens, we have constructed a 3D virtual environment designed to emulate common tasks used to evaluate patients, such as fixating on a point, conducting smooth pursuit of an object, or executing saccades. These virtual tasks are designed to elicit eye movements commonly associated with neurodegenerative disease, such as abnormal saccades, square wave jerks, and ocular tremor. Next, we conducted experiments with 9 patients with a diagnosis of Parkinson's disease and 7 healthy controls to test the system's potential to emulate tasks for clinical diagnosis. We then applied eye tracking algorithms and image enhancement to the eye recordings taken during the experiment and conducted a short follow-up study with two physicians for evaluation. Results showed that our VR interface was able to elicit five common types of movements usable for evaluation, physicians were able to confirm three out of four abnormalities, and visualizations were rated as potentially useful for diagnosis.
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Ocular and visual disorders in Parkinson's disease: Common but frequently overlooked. Parkinsonism Relat Disord 2017; 40:1-10. [PMID: 28284903 DOI: 10.1016/j.parkreldis.2017.02.014] [Citation(s) in RCA: 77] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/11/2016] [Revised: 02/09/2017] [Accepted: 02/16/2017] [Indexed: 11/23/2022]
Abstract
Patients with Parkinson's disease (PD) often compensate for their motor deficits by guiding their movements visually. A wide range of ocular and visual disorders threatens the patients' ability to benefit optimally from visual feedback. These disorders are common in patients with PD, yet they have received little attention in both research and clinical practice, leading to unnecessary - but possibly treatable - disability. Based on a literature search covering 50 years, we review the range of ocular and visual disorders in patients with PD, and classify these according to anatomical structures of the visual pathway. We discuss six common disorders in more detail: dry eyes; diplopia; glaucoma and glaucoma-like visual problems; impaired contrast and colour vision; visuospatial and visuoperceptual impairments; and visual hallucinations. In addition, we review the effects of PD-related pharmacological and surgical treatments on visual function, and we offer practical recommendations for clinical management. Greater awareness and early recognition of ocular and visual problems in PD might enable timely instalment of tailored treatments, leading to improved patient safety, greater independence, and better quality of life.
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243
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Friedman JH. Misperceptions and Parkinson's disease. J Neurol Sci 2017; 374:42-46. [PMID: 28073433 DOI: 10.1016/j.jns.2016.12.059] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 12/27/2016] [Indexed: 01/08/2023]
Abstract
Most of the neurobehavioral aspects of Parkinson's disease have been well established and studied, but many are not well known, and hardly studied. This article focuses on several behavioral abnormalities that are common, and frequently cause difficulty for the patient and family due to lack of recognition as part of the disease. While it is well known that L-Dopa dyskinesias are frequently not recognized or under appreciated by patients, a similar lack of recognition may affect the patient's own speech volume, where their center of gravity is located, whether they are tilted to one side, and their under-recognition of others' emotional displays. In addition, PD patients are often misperceived by others incorrect impression of their emotional and cognitive state based purely on facial expression. These changes and others are briefly reviewed.
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Affiliation(s)
- Joseph H Friedman
- Butler Hospital, Dept of Neurology, Warren Alpert Medical School of Brown University, 345 Blackstone Blvd, Providence, RI 02906, USA.
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244
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ffytche DH, Aarsland D. Psychosis in Parkinson's Disease. INTERNATIONAL REVIEW OF NEUROBIOLOGY 2017; 133:585-622. [DOI: 10.1016/bs.irn.2017.04.005] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
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245
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Stuart S, Hickey A, Galna B, Lord S, Rochester L, Godfrey A. iTrack: instrumented mobile electrooculography (EOG) eye-tracking in older adults and Parkinson's disease. Physiol Meas 2016; 38:N16-N31. [PMID: 27941232 DOI: 10.1088/1361-6579/38/1/n16] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
Detection of saccades (fast eye-movements) within raw mobile electrooculography (EOG) data involves complex algorithms which typically process data acquired during seated static tasks only. Processing of data during dynamic tasks such as walking is relatively rare and complex, particularly in older adults or people with Parkinson's disease (PD). Development of algorithms that can be easily implemented to detect saccades is required. This study aimed to develop an algorithm for the detection and measurement of saccades in EOG data during static (sitting) and dynamic (walking) tasks, in older adults and PD. Eye-tracking via mobile EOG and infra-red (IR) eye-tracker (with video) was performed with a group of older adults (n = 10) and PD participants (n = 10) (⩾50 years). Horizontal saccades made between targets set 5°, 10° and 15° apart were first measured while seated. Horizontal saccades were then measured while a participant walked and executed a 40° turn left and right. The EOG algorithm was evaluated by comparing the number of correct saccade detections and agreement (ICC2,1) between output from visual inspection of eye-tracker videos and IR eye-tracker. The EOG algorithm detected 75-92% of saccades compared to video inspection and IR output during static testing, with fair to excellent agreement (ICC2,1 0.49-0.93). However, during walking EOG saccade detection reduced to 42-88% compared to video inspection or IR output, with poor to excellent (ICC2,1 0.13-0.88) agreement between methodologies. The algorithm was robust during seated testing but less so during walking, which was likely due to increased measurement and analysis error with a dynamic task. Future studies may consider a combination of EOG and IR for comprehensive measurement.
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