Correlations of Neuropsychological and Metabolic Brain Changes in Parkinson's Disease and Other α-Synucleinopathies

Cognitive impairment is a common feature in Parkinson's disease (PD) and other α-synucleinopathies as 80% of PD patients develop dementia within 20 years. Early cognitive changes in PD patients present as a dysexecutive syndrome, broadly characterized as a disruption of the fronto-striatal dopamine network. Cognitive deficits in other domains (recognition memory, attention processes and visuospatial abilities) become apparent with the progression of PD and development of dementia. In dementia with Lewy bodies (DLB) the cognitive impairment develops early or even precedes parkinsonism and it is more pronounced in visuospatial skills and memory. Cognitive impairment in the rarer α-synucleinopathies (multiple system atrophy and pure autonomic failure) is less well studied. Metabolic brain imaging with positron emission tomography and [18F]-fluorodeoxyglucose (FDG-PET) is a well-established diagnostic method in neurodegenerative diseases, including dementias. Changes in glucose metabolism precede those seen on structural magnetic resonance imaging (MRI). Reduction in glucose metabolism and atrophy have been suggested to represent consecutive changes of neurodegeneration and are linked to specific cognitive disorders (e.g., dysexecutive syndrome, memory impairment, visuospatial deficits etc.). Advances in the statistical analysis of FDG-PET images enabling a network analysis broadened our understanding of neurodegenerative brain processes. A specific cognitive pattern ...
Source: Frontiers in Neurology - Category: Neurology Source Type: research

Related Links:

This article gives a summary of the main results of MEL therapy in some neurological diseases and insomnia approved by this consensus group. Exogenous MEL, which crosses the blood-brain barrier, has been used as a treatment in its two available forms: an immediate release form that principally shows a chronobiotic action and a long release form that mimics the physiological MEL secretion rhythm and is used to replace reduced physiological secretion. MEL secretion decreases frequently with age, mostly in elderly insomniacs and dementia patients. Results of level A studies show that MEL therapy, used as an add-on treatment, ...
Source: Revue Neurologique - Category: Neurology Tags: Rev Neurol (Paris) Source Type: research
In conclusion, we found that different types of OT and orthostatic myoclonus were diagnosed by electrophysiological evaluation and neuroimaging tools even if they showed the same symptoms as “shaky leg.” In addition, it is possible to roughly estimate the response to med ication according to the type of OT and the cause. To clarify the pathophysiology of OT, a large number of longitudinal cohort studies and detailed neuroimaging and electrophysiological evaluations are needed.Neurodegener Dis
Source: Neurodegenerative Diseases - Category: Neurology Source Type: research
In conclusion, we found that different types of OT and orthostatic myoclonus were diagnosed by electrophysiological evaluation and neuroimaging tools even if they showed the same symptoms as "shaky leg." In addition, it is possible to roughly estimate the response to medication according to the type of OT and the cause. To clarify the pathophysiology of OT, a large number of longitudinal cohort studies and detailed neuroimaging and electrophysiological evaluations are needed. PMID: 32911473 [PubMed - as supplied by publisher]
Source: Neuro-Degenerative Diseases - Category: Neurology Authors: Tags: Neurodegener Dis Source Type: research
Authors: Cummings J Abstract Neuropsychiatric syndromes and symptoms play increasingly important roles in research diagnostic criteria for neurodegenerative disorders. Diagnostic criteria were reviewed including those for dementia, Alzheimer's disease, mild cognitive impairment, mild behavioral impairment, prodromal Alzheimer's disease, dementia with Lewy bodies, prodromal dementia with Lewy bodies, Parkinson's disease, multiple system atrophy, frontotemporal dementia, primary progressive aphasia, progressive supranuclear palsy, corticobasal degeneration, traumatic encephalopathy syndrome, Huntington' disease, amyo...
Source: The American Journal of Geriatric Psychiatry - Category: Psychiatry Tags: Am J Geriatr Psychiatry Source Type: research
This article summarizes a century of sleep research to examine the maladies of dreaming, their pathophysiologic significance, and management. RECENT FINDINGS Under healthy physiologic conditions, REM sleep is characterized by vivid mentation combined with skeletal muscle paralysis. The loss of REM sleep atonia in RBD results in vivid, potentially injurious dream enactment to patients and bed partners. RBD is common, affecting at least 1% of the population and is primarily caused by α-synuclein pathology of REM sleep–related brainstem neurons. The majority of patients with RBD ultimately develop a neurodegene...
Source: CONTINUUM: Lifelong Learning in Neurology - Category: Neurology Tags: REVIEW ARTICLES Source Type: research
Authors: Aubignat M, Tir M, Krystkowiak P Abstract Parkinson's disease is the second most common neurodegenerative disease after Alzheimer's disease. The pathophysiology of Parkinson's disease is complex and imperfectly known. Primum movens is abnormal intra-neuronal accumulation of the protein α-synuclein, leading to metabolic disturbances and neurodegeneration. This abnormal accumulation of α-synuclein is also found in dementia with Lewy bodies and multiple system atrophy, which together with Parkinson's disease form the group of α-synucleinopathies. Well known by its motor signs (bradykinesia, ...
Source: Revue de Medecine Interne - Category: Internal Medicine Tags: Rev Med Interne Source Type: research
Dementia is a syndrome and an umbrella term that encompasses Alzheimer, Parkinson and autism diseases. These diseases are by far the most common cause of dementia; therefore this investigation will chiefly include these disorders, with a limited discussion of few other disorders related to dementia. Alzheimer’s disease (AD) is characterized by the accumulation of cerebral β-amyloid plaques, tau proteins and memory loss; Parkinson by the deterioration of brain cells which regulate the movement of body parts and produce dopamine; and autism by abnormalities of social disorder and difficulty in communicating and fo...
Source: Current Nutrition and Food Science - Category: Nutrition Source Type: research
Abstract Since its first description in 1986 by Dr. Carlos Schenck, and his group's subsequent report of the delayed emergence of a Parkinsonian disorder in idiopathic RBD patients one decade later, RBD has emerged in recent years as one of the most promising markers of prodromal Parkinson's (References 2, 3). RBD is present in 25-58% of patients with Parkinson's disease and up to 90% of those with Dementia with Lewy Bodies (DLB) or Multiple System Atrophy (MSA). In a substantial proportion of these patients RBD onset occurs before motor symptoms. Critically, when seen in isolation, RBD is a highly specific marker...
Source: Neurobiology of Disease - Category: Neurology Authors: Tags: Neurobiol Dis Source Type: research
Abnormal intraneuronal accumulation of the presynaptic protein α-synuclein (α-syn) is implicated in the etiology of dementia with Lewy bodies (DLB) and Parkinson's disease with dementia (PDD). Recent work revealed that mice expressing human α-syn with the alanine-53-threonine (A53T) mutation have a similar phenotype to the human condition, exhibiting long-term potentiation deficits, learning and memory deficits, and inhibitory hippocampal remodeling, all of which were reversed by genetic ablation of microtubule-associated protein tau. Significantly, memory deficits were associated with histological signs ...
Source: Frontiers in Neurology - Category: Neurology Source Type: research
Parkinson’s disease (PD) is characterized by the progressive loss of dopaminergic neurons in the substantia nigra. However, other non-dopaminergic neuronal systems such as the serotonergic system are also involved. Serotonergic dysfunction is associated with non-motor symptoms and complications, including anxiety, depression, dementia, and sleep disturbances. This pathology reduces patient quality of life. Interaction between the serotonergic and other neurotransmitters systems such as dopamine, noradrenaline, glutamate, and GABA controls the activity of striatal neurons and are particularly interesting for understan...
Source: Frontiers in Neuroanatomy - Category: Neurology Source Type: research
More News: Brain | Dementia | MRI Scan | Neurology | Parkinson's Disease | PET Scan | Sleep Disorders | Sleep Medicine | Statistics