scholarly journals Dissociable effects of age and Parkinson’s disease on instruction based learning

2021 ◽  
Author(s):  
Beth L Parkin ◽  
Richard E Daws ◽  
Ines Das-Neves ◽  
Ines R Violante ◽  
Eyal Soreq ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Resonance Spectroscopy ◽  
Gamma Aminobutyric Acid ◽  
Learning Tasks ◽  
Behavioural Characteristics ◽  
Dorsolateral Prefrontal ◽  
Future Work ◽  
First Time ◽  
Discrimination Rules

Abstract The cognitive deficits associated with Parkinson’s disease vary across individuals and change across time, with implications for prognosis and treatment. Key outstanding challenges are to define the distinct behavioural characteristics of this disorder and develop diagnostic paradigms that can assess these sensitively in individuals. In a previous study we measured different aspects of attentional control in Parkinson’s disease using an established fMRI switching paradigm 1. We observed no deficits for the aspects of attention the task was designed to examine; instead those with Parkinson’s disease learnt the operational requirements of the task more slowly. We hypothesised that a subset of people with early to mid-stage Parkinson’s might be impaired when encoding rules for performing new tasks. Here, we directly test this hypothesis and investigate whether deficits in instruction-based learning represent a characteristic of Parkinson’s Disease. Seventeen participants with Parkinson’s disease (8 male; mean age: 61.2 years), eighteen older adults (8 male; mean age: 61.3 years) and twenty younger adults (10 males; mean age: 26.7 years) undertook a simple instruction-based learning paradigm in the MRI scanner. They sorted sequences of coloured shapes according to binary discrimination rules that were updated at two-minute intervals. Unlike common reinforcement learning tasks, the rules were unambiguous, being explicitly presented; consequently, there was no requirement to monitor feedback or estimate contingencies. Despite its simplicity, a third of the Parkinson’s group, but only one older adult, showed marked increases in errors, 4SD greater than the worst-performing young adult. The pattern of errors was consistent, reflecting a tendency to misbind discrimination rules. The misbinding behaviour was coupled with reduced frontal, parietal and anterior caudate activity when rules were being encoded, but not when attention was initially oriented to the instruction slides or when discrimination trials were performed. Concomitantly, Magnetic Resonance Spectroscopy showed reduced gamma-Aminobutyric acid (GABA) levels within the mid-dorsolateral prefrontal cortices of individuals who made misbinding errors. These results demonstrate, for the first time, that a subset of early to mid-stage people with Parkinson’s have substantial deficits when binding new task rules in working memory. Given the ubiquity of instruction-based learning, these deficits are likely to impede daily living. They will also confound clinical assessment of other cognitive processes. Future work should determine the value of instruction-based learning as a sensitive early marker of cognitive decline and as a measure of responsiveness to therapy in Parkinson disease.

scholarly journals Dissociable Effects of Age and Parkinson’s Disease on Instruction Based Learning

2020 ◽  
Author(s):  
Beth Parkin ◽  
Richard E Daws ◽  
Ines Das Neves ◽  
Ines Violante ◽  
Eyal Soreq ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Resonance Spectroscopy ◽  
Gamma Aminobutyric Acid ◽  
Learning Tasks ◽  
Dorsolateral Prefrontal ◽  
Behavioural Phenotypes ◽  
Future Work ◽  
First Time ◽  
Discrimination Rules

The psychological deficits associated with Parkinson’s disease vary across individuals and change across time, with implications for prognosis and treatment. Key outstanding challenges are to define the distinct behavioural phenotypes of this disorder and develop diagnostic paradigms that can assess these sensitively in individuals. In a previous study we measured different aspects of attentional control in Parkinson’s disease using an established fMRI switching paradigm (Gruszka et al., 2017). We observed no deficits for the aspects of attention the task was designed to examine; instead those with Parkinson’s disease learnt the operational requirements of the task more slowly. We hypothesised that a subset of people with early to mid-stage Parkinson’s might be impaired when encoding rules for performing new tasks. Here, we directly test this hypothesis and investigate whether deficits in instruction based learning represent a potential phenotype. Seventeen participants with Parkinson’s disease (8 male; mean age: 61.2 years), eighteen older adults (8 male; mean age: 61.3 years) and twenty younger adults (10 males; mean age: 26.7 years) undertook a simple instruction based learning paradigm in the MRI scanner. They sorted sequences of coloured shapes according to binary discrimination rules that were updated at two-minute intervals. Unlike common reinforcement learning tasks, the rules were unambiguous, being explicitly presented; consequently, there was no requirement to monitor feedback or estimate contingencies. Despite its simplicity, a third of the Parkinson’s group, but only one older adult, showed marked increases in errors, 4SD greater than the worst-performing young adult. The pattern of errors was consistent, reflecting a tendency to misbind discrimination rules. The misbinding behaviour was coupled with reduced frontal, parietal and anterior caudate activity when rules were being encoded, but not when attention was initially oriented to the instruction slides or when discrimination trials were performed. Concomitantly, Magnetic Resonance Spectroscopy showed reduced gamma-Aminobutyric acid (GABA) levels within the mid-dorsolateral prefrontal cortices of individuals who made misbinding errors. These results demonstrate, for the first time, that a subset of early to mid-stage people with Parkinson’s have substantial deficits when binding new task rules in working memory. Given the ubiquity of instruction based learning, these deficits are likely to impede daily living. They will also confound clinical assessment of other psychological processes. Future work should determine the value of instruction based learning as a sensitive early marker of cognitive decline and as a measure of responsiveness to therapy in Parkinson disease.

scholarly journals Diagnosis of Parkinson’s Disease. Part 1. The Potential of Functional Neuroimaging

Doctor Ru ◽  
2020 ◽  
Vol 19 (9) ◽  
pp. 6-12
Author(s):  
M.R. Sapronova ◽  
◽  
D.V. Dmitrenko ◽  
N.A. Schnaider ◽  
A.A. Molgachev ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Functional Neuroimaging ◽  
Single Photon ◽  
Photon Emission ◽  
Transcranial Sonography ◽  
Emission Computed Tomography ◽  
Resonance Spectroscopy ◽  
Positron Emission ◽  
Neuroimaging Techniques

Objective of the Review: To describe available functional neuroimaging techniques for use in patients with Parkinson’s disease (PD). Key Points: Parkinson’s disease is a neurodegenerative disorder which affects 2-3% of people older than 65 years. The main neuropathological hallmarks of PD are an accumulation of alpha-synuclein aggregates in the cellular cytoplasm and a loss of neurons in the pars compacta of the substantia nigra, leading to dopamine deficiency. Clinical symptoms of the disease appear when the underlying neural impairment is already advanced, which significantly reduces treatment options. Over the two last decades, functional neuroimaging techniques such as positron emission tomography, single-photon emission computed tomography, proton magnetic resonance spectroscopy, and transcranial sonography have increasingly been used for diagnosing PD during patients’ lifetime and understanding the neuropathological mechanisms and compensatory reactions underlying its symptoms, as well as for monitoring the progression of PD. Conclusion: Modern functional neuroimaging techniques not only facilitate differential diagnosis of PD, but also make it possible to detect the disease at its early/preclinical stage. Keywords: Parkinson’s disease, neuroimaging, positron emission tomography, single-photon emission computed tomography, proton magnetic resonance spectroscopy, transcranial sonography.

scholarly journals Consistency and Stability of Motor Subtype Classifications in Patients With de novo Parkinson’s Disease

2021 ◽  
Vol 15 ◽  
Author(s):  
Jingru Ren ◽  
Chenxi Pan ◽  
Yuqian Li ◽  
Lanting Li ◽  
Ping Hua ◽  
...  
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
De Novo ◽  
Classification Systems ◽  
Motor Symptoms ◽  
Chi Squared ◽  
Baseline Evaluation ◽  
The Stability ◽  
First Time ◽  
Non Motor Symptoms

ObjectivePatients with Parkinson’s disease (PD) are commonly classified into subtypes based on motor symptoms. The aims of the present study were to determine the consistency between PD motor subtypes, to assess the stability of PD motor subtypes over time, and to explore the variables influencing PD motor subtype stability.MethodsThis study was part of a longitudinal study of de novo PD patients at a single center. Based on three different motor subtype classification systems proposed by Jankovic, Schiess, and Kang, patients were respectively categorized as tremor-dominant/indeterminate/postural instability and gait difficulty (TD/indeterminate/PIGD), TDS/mixedS/akinetic-rigidS (ARS), or TDK/mixedK/ARK at baseline evaluation and then re-assessed 1 month later. Demographic and clinical characteristics were recorded at each evaluation. The consistency between subtypes at baseline evaluation was assessed using Cohen’s kappa coefficient (κ). Additional variables were compared between PD subtype groups using the two-sample t-test, Mann–Whitney U-test or Chi-squared test.ResultsOf 283 newly diagnosed, untreated PD patients, 79 were followed up at 1 month. There was fair agreement between the Jankovic, Schiess, and Kang classification systems (κS = 0.383 ± 0.044, κK = 0.360 ± 0.042, κSK = 0.368 ± 0.038). Among the three classification systems, the Schiess classification was the most stable and the Jankovic classification was the most unstable. The non-motor symptoms questionnaire (NMSQuest) scores differed significantly between PD patients with stable and unstable subtypes based on the Jankovic classification (p = 0.008), and patients with a consistent subtype had more severe NMSQuest scores than patients with an inconsistent subtype.ConclusionFair consistency was observed between the Jankovic, Schiess, and Kang classification systems. For the first time, non-motor symptoms (NMSs) scores were found to influence the stability of the TD/indeterminate/PIGD classification. Our findings support combining NMSs with motor symptoms to increase the effectiveness of PD subtypes.

scholarly journals Schizophrenia as Potential Trigger for Melanoma Development and Progression! The Psycho-Neuro-Endocrine-Oncology (P.N.E.O) Network!

2018 ◽  
Vol 6 (8) ◽  
pp. 1442-1445
Author(s):  
Georgi Tchernev ◽  
Ilia Lozev ◽  
Ivanka Temelkova ◽  
Svetoslav Chernin ◽  
Irina Yungareva
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Nervous Tissue ◽  
World Literature ◽  
Careful Analysis ◽  
Potential Trigger ◽  
Patient Groups ◽  
Neuroectodermal Origin ◽  
High Level ◽  
First Time

BACKGROUND: Skin, nervous tissue, dopamine and melanoma share a common neuroectodermal origin. Hence, processes that modulate nervous tissue formation, patient mental status, motor regulation of individuals, and skin cancerogenesis are inextricably linked. Psycho-neuro-endocrine oncology (or dermato-oncology), i.e. P.N.E.O., is a new model or trend in medicine and science presented for the first time in the world literature by us, that aims to examine the relationship between the mental state, the hormones and the malignant transformation. Schizophrenia and Parkinson’s disease are the two main patterns of disease where the main symptoms are related to dopamine levels in the human body. According to our analyses of the available literature, the amount of dopamine is related to the incidence of melanocytic or non-melanocytic cutaneous tumours in patients with central nervous system diseases and those affecting the motor function and coordination. Such patterns of interaction are extremely indicative of the elucidation of the ubiquitous hypothesis or statement: “My illness is on a mental basis, caused by stress ...”CASE PRESENTATION: We present a 44-year-old patient with untreated schizophrenia for approximately 25 years, associated with advanced acral localised melanoma. Schizophrenia is generally associated with a higher level of dopamine, which is also a key precursor to melanin synthesis. After a careful analysis of all literature on melanoma in patients with 1) treated and untreated schizophrenia, 2) those with untreated and untreated forms of Parkinson’s disease, it would be logical to conclude that the high level of dopamine in the described patient groups is a risk factor for the development of melanoma.CONCLUSIONS: The possible mechanisms for the occurrence of malignant melanoma within the so-called psycho/neuro/endocrine oncology (P.N.E.O.), as well as the effective methods of prevention, are under discussion.

scholarly journals The Ameliorative Effects of the Ethyl Acetate Extract ofSalicornia europaeaL. and Its Bioactive Candidate, Irilin B, on LPS-Induced Microglial Inflammation and MPTP-Intoxicated PD-Like Mouse Model

2019 ◽  
Vol 2019 ◽  
pp. 1-16 ◽  
Author(s):  
Joonsoo Kim ◽  
Govindarajan Karthivashan ◽  
Mee-Hyang Kweon ◽  
Deuk-Hoi Kim ◽  
Dong-Kug Choi
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Therapeutic Potential ◽  
Motor Deficits ◽  
Resonance Spectroscopy ◽  
Potential Candidate ◽  
Nigrostriatal Pathway ◽  
Salicornia Europaea ◽  
Isolation And Purification

Hyperactivation of microglia, the resident innate immune cells of the central nervous system, exacerbates various neurodegenerative disorders, including Parkinson’s disease (PD). Parkinson’s disease is generally characterized by a severe loss of dopaminergic neurons in the nigrostriatal pathway, with substantial neuroinflammation and motor deficits. This was experimentally replicated in animal models, using neurotoxins, i.e., LPS (lipopolysaccharides) and MPTP (1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine).Salicornia europaeaL. (SE) has been used as a dietary supplement in Korea and Europe for several years, due to its nutritional and therapeutic value. In this study, we intend to investigate the antineuroinflammatory and anti-PD-like effects of the bioactive fraction/candidate of the SE extract. Initially, we screened various fractions of SE extract using anin vitroantioxidant assay. The optimal fraction was investigated for itsin vitroantineuroinflammatory potential in LPS-stimulated BV-2 microglial cells andin vivoanti-PD-like potential in MPTP-intoxicated mice. Subsequently, to identify the potential candidate responsible for the elite therapeutic potential of the optimal fraction, we conducted antioxidant activity-guided isolation and purification; the bioactive candidate was structurally characterized using nuclear magnetic resonance spectroscopy and chromatographic techniques and further investigated for itsin vitroantioxidative and antineuroinflammatory potential. The results of our study indicate that SE-EA and its bioactive candidate, Irilin B, effectively alleviate the deleterious effect of microglia-mediated neuroinflammation and promote antioxidative effects. Thus, they exhibit potential as therapeutic candidates against neuroinflammatory and oxidative stress-mediated PD-like neurodegenerative complications.

scholarly journals Magnetic Resonance Spectroscopy in the Diagnosis of Dementia with Lewy Bodies

2014 ◽  
Vol 2014 ◽  
pp. 1-7 ◽  
Author(s):  
Radoslaw Magierski ◽  
Tomasz Sobow
Keyword(s):  
Parkinson’S Disease ◽  
Parkinson's Disease ◽  
Magnetic Resonance ◽  
Magnetic Resonance Spectroscopy ◽  
Dementia With Lewy Bodies ◽  
Clinical Symptoms ◽  
Clinical Signs ◽  
Lewy Bodies ◽  
Resonance Spectroscopy ◽  
Diagnosis Of Dementia

Dementia with Lewy bodies (DLB) is considered to be the second most frequent primary degenerative dementing illness after Alzheimer’s disease (AD). DLB, together with Parkinson’s disease (PD), Parkinson’s disease with dementia (PDD) belong toα-synucleinopathies—a group of neurodegenerative diseases associated with pathological accumulation of theα-synuclein protein. Dementia due to PD and DLB shares clinical symptoms and neuropsychological profiles. Moreover, the core features and additional clinical signs and symptoms for these two very similar diseases are largely the same. Neuroimaging seems to be a promising method in differential diagnosis of dementia studies. The development of imaging methods or other objective measures to supplement clinical criteria for DLB is needed and a method which would accurately facilitate diagnosis of DLB prior to death is still being searched. Proton magnetic resonance spectroscopy (1H-MRS) provides a noninvasive method of assessing anin vivobiochemistry of brain tissue. This review summarizes the main results obtained from the application of neuroimaging techniques in DLB cases focusing on1H-MRS.

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