Cortical hypometabolism on FDG-PET is a well-established neuroimaging biomarker of cognitive impairment in Parkinson's disease (PD), but its pathophysiologic origins are incompletely understood. Cholinergic basal forebrain (cBF) degeneration is a prominent pathological feature of PD-related cognitive impairment and may contribute to cortical hypometabolism through cholinergic denervation of cortical projection areas. Here, we investigated in-vivo associations between subregional cBF volumes on 3T-MRI, cortical hypometabolism on [F]FDG-PET, and cognitive deficits in a cohort of 95 PD participants with varying degrees of cognitive impairment.
View Article and Find Full Text PDFImportance: Functional movement disorders (FMDs) are frequent and disabling neurological disorders with a substantial socioeconomic impact. Few randomized studies have analyzed the effectiveness of combined physiotherapy and psychotherapy in patients' quality of life.
Objective: To assess the efficacy of multidisciplinary treatment (physiotherapy plus cognitive behavioral therapy) in FMDs.
Background: Deep brain stimulation (DBS) is a highly efficient, evidence-based therapy to alleviate symptoms and improve quality of life in movement disorders such as Parkinson's disease, essential tremor, and dystonia, which is also being applied in several psychiatric disorders, such as obsessive-compulsive disorder and depression, when they are otherwise resistant to therapy.
Summary: At present, DBS is clinically applied in the so-called open-loop approach, with fixed stimulation parameters, irrespective of the patients' clinical state(s). This approach ignores the brain states or feedback from the central nervous system or peripheral recordings, thus potentially limiting its efficacy and inducing side effects by stimulation of the targeted networks below or above the therapeutic level.
Neural adaptations to resistance training (RT) and their correlation with muscle strength remain partially understood. We conducted a systematic review and multivariate meta-analysis to examine the effects of metronome-paced (MP), self-paced (SP), and isometric (IM) training on M1 and corticospinal pathway activity. Following MP RT, a significant increase in corticospinal excitability was observed, correlating with increased strength.
View Article and Find Full Text PDFBackground: Hyperhomocysteinemia is considered an independent risk factor for cognitive impairment.
Objective: To study the correlation between homocysteine levels and cognitive impairment in patients with PD.
Methods: We conducted a case-control study that included 246 patients with PD, of whom 32 were cognitively impaired.
Tourette syndrome (TS) is characterized by multiple motor and vocal tics, and high-comorbidity rates with other neuropsychiatric disorders. Obsessive compulsive disorder (OCD), attention deficit hyperactivity disorder (ADHD), autism spectrum disorders (ASDs), major depressive disorder (MDD), and anxiety disorders (AXDs) are among the most prevalent TS comorbidities. To date, studies on TS brain structure and function have been limited in size with efforts mostly fragmented.
View Article and Find Full Text PDFIntroduction: We aimed to assess associations between multimodal neuroimaging measures of cholinergic basal forebrain (CBF) integrity and cognition in Parkinson's disease (PD) without dementia.
Methods: The study included a total of 180 non-demented PD patients and 45 healthy controls, who underwent structural MRI acquisitions and standardized neurocognitive assessment through the PD-Cognitive Rating Scale (PD-CRS) within the multicentric COPPADIS-2015 study. A subset of 73 patients also had Diffusion Tensor Imaging (DTI) acquisitions.
Background: The neutrophil-to-lymphocyte ratio (NLR) in peripheral blood is a well-established inflammatory marker, but its role in Parkinson's disease (PD) remains unclear.
Objectives: To determine whether a different peripheral immune profile and NLR were present in PD patients.
Methods: We conducted a case-control study that included 377 PD patients and 355 healthy controls (HCs).
Purpose: To determine whether the development of levodopa-induced dyskinesia (LID) in Parkinson disease (PD) specifically relates to dopaminergic depletion in sensorimotor-related subregions of the striatum.
Methods: Our primary study sample consisted of 185 locally recruited PD patients, of which 73 (40%) developed LID. Retrospective 123I-FP-CIT SPECT data were used to quantify the specific dopamine transporter (DAT) binding ratio within distinct functionally defined striatal subregions related to limbic, executive, and sensorimotor systems.
Background: Surgical resection of diffuse low-grade gliomas (DLGGs) involving cortical eloquent areas and subcortical functional pathways represents a challenge in neurosurgery. Patient-specific, 3-dimensional (3D)-printed models of head and brain structures have emerged in recent years as an educational and clinical tool for patients, doctors, and surgical residents.
Methods: Using multimodal high-definition magnetic resonance imaging data, which incorporates information from specific task-based functional neuroimaging and diffusion tensor imaging tractography and rapid prototyping technologies with specialized software and "in-house" 3D printing, we were able to generate 3D-printed head models that were used for preoperative patient education and consultation, surgical planning, and resident training in 2 complicated DLGG surgeries.
Maladaptive cortical plasticity has been described in individuals with heroin and methamphetamine addiction and may mediate other substance abuse disorders. It is unknown whether cannabis dependence in humans alters the capacity for induction of cortical plasticity. The aim of this study was to non-invasively investigate cortical plasticity with transcranial magnetic stimulation in young adults who meet DSM-5 criteria for cannabis use disorder (CUD).
View Article and Find Full Text PDFAim: Besides their metabolic and endocrine functions, the growth hormone (GH) and its mediated factor, the insulin-like growth factor I (IGF-I), have been implicated in different brain functions, including neurogenesis. Long-lasting elevated GH and IGF-I levels result in non-reversible somatic, endocrine and metabolic morbidities. However, the subcutaneous implantation of the GH-secreting (GH-S) GC cell line in rats leads to the controllable over-secretion of GH and elevated IGF-I levels, allowing the experimental study of their short-term effects on brain functions.
View Article and Find Full Text PDFThere is increasing evidence that supports the role of the cerebellum in the pathophysiology of dystonia. We used transcranial magnetic stimulation to test the hypothesis that patients with cervical dystonia may have a disrupted cerebellar cortical connectivity at rest, and that cerebellar plasticity is altered too. We enrolled 12 patients with isolated cervical dystonia and 13 controls.
View Article and Find Full Text PDFTraditionally, Parkinson's disease (PD) has been considered a single neurotransmitter (dopaminergic) disease. However, research over the past 20 years has shed light on the involvement of multiple neurotransmission systems, in particular, the cholinergic system. Research has mainly focused on the role of this system in the pathophysiology of PD and its implications in the development of motor and non-motor disorders.
View Article and Find Full Text PDFSee Vidailhet et al. (doi:10.1093/brain/awx140) for a scientific commentary on this article.
View Article and Find Full Text PDFParkinson's disease (PD) patients who present with tremor and maintain a predominance of tremor have a better prognosis. Similarly, PD patients with high levels of uric acid (UA), a natural neuroprotectant, have also a better disease course. Our aim was to investigate whether PD motor subtypes differ in their levels of UA, and if these differences correlate with the degree of dopamine transporter (DAT) availability.
View Article and Find Full Text PDFObjectives: Euthymic patients with bipolar disorder (BD) have deficits in cortical inhibition. However, whether cortical inhibitory deficits are trait- or state-dependent impairments is not yet known and their relationship with psychiatric symptoms is not yet understood. In the present study, we examined trait- and state-dependent cortical inhibitory deficits and evaluated the potential clinical significance of these deficits.
View Article and Find Full Text PDFBackground: Tourette syndrome is a disorder characterized by persistent motor and vocal tics, and frequently accompanied by the comorbidities attention deficit hyperactivity disorder and obsessive-compulsive disorder. Impaired synaptic neurotransmission has been implicated in its pathogenesis. Our aim was to investigate the association of 28 candidate genes, including genes related to synaptic neurotransmission and neurotrophic factors, with Tourette syndrome.
View Article and Find Full Text PDFWorking memory (WM) has been defined as a cerebral function which allows us to maintain and manipulate information "online". One of the most widely used paradigms to assess WM is the n-back test. Despite its extensive application, some authors have questioned its capacity to assess the manipulation of WM load.
View Article and Find Full Text PDFBackground: Recent studies have shown altered cortical plasticity in adult patients with Tourette syndrome. However, the clinical significance of this finding remains elusive.
Methods: Motor cortical plasticity was evaluated in 15 adult patients with severe Tourette syndrome and 16 healthy controls using the paired associative stimulation protocol by transcranial magnetic stimulation.
Objective: To assess the utility of the desmopressin (DDAVP) test in the diagnosis and follow-up of a cyclical Cushing's disease (CCS) case.
Material And Methods: Laboratory tests included morning and midnight serum cortisol levels, 24h urine free cortisol excretion, midnight salivary cortisol levels, serum cortisol levels after low (1 mg) and high (8 mg) dexamethasone, plasma ACTH and serum cortisol levels after DDAVP. Magnetic resonance imaging (MRI) was used to assess the presence of a pituitary adenoma.
Patients with active untreated acromegaly show mild to moderate neurocognitive disorders that are associated to chronic exposure to growth hormone (GH) and insulin-like growth factor (IGF-I) hypersecretion. However, it is unknown whether these disorders improve after controlling GH/IGF-I hypersecretion. The aim of this study was to compare neurocognitive functions of patients who successfully underwent GH-secreting adenoma transsphenoidal surgery (cured patients) with patients with naive acromegaly.
View Article and Find Full Text PDFBackground: A single midnight serum cortisol (MSC) test has been reported to possess the best sensitivity and specificity for diagnosing Cushing's syndrome (CS). However, this test requires patient hospitalization, making it costly. This paper aims to compare the hospital budget impact and accuracy of using midnight salivary cortisol (MSVC), as opposed to MSC, in the diagnosis of hypercortisolism.
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