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Anna Elisabetta Vaudano, Sara Olivotto, Andrea Ruggieri, Giuliana Gessaroli, Valentina De Giorgis, Antonia Parmeggiani, Pierangelo Veggiotti, Stefano Meletti
PURPOSE: To provide imaging biomarkers of generalized spike-and-wave discharges (GSWD) in patients with GLUT1 deficiency syndrome (GLUT1DS). METHODS: Eighteen GLUT1DS patients with pathogenetic mutation in SLC2A1 gene were studied by means of Video-EEG simultaneously recorded with functional MRI (VideoEEG-fMRI). A control group of sex and age-matched patients affected by Genetic Generalized Epilepsy (GGE) with GSWD were investigated with the same protocol. Within and between groups comparison was performed as appropriated...
2017: NeuroImage: Clinical
A M M van der Stouwe, C M Toxopeus, B M de Jong, P Yavuz, G Valsan, B A Conway, K L Leenders, N M Maurits
We investigated simple directional hand movements based on different degrees of muscle co-activity, at behavioral and cerebral level in healthy subjects and Parkinson's disease (PD) patients. We compared "singular" movements, dominated by the activity of one agonist muscle, to "composite" movements, requiring conjoint activity of multiple muscles, in a center-out (right hand) step-tracking task. Behavioral parameters were obtained by EMG and kinematic recordings. fMRI was used to investigate differences in underlying brain activations between PD patients (N = 12) and healthy (age-matched) subjects (N = 18)...
2015: Frontiers in Human Neuroscience
Elinor Tzvi, Anne Stoldt, Karsten Witt, Ulrike M Krämer
The fast and slow learning stages of motor sequence learning are suggested to be realized through plasticity in a distributed cortico-striato-cerebellar network. To better understand the causal interactions within this network in the different phases of motor sequence learning, we investigated the effective connectivity within this network during encoding (Day 1) and after consolidation (Day 2) of a serial reaction time task. Using Dynamic Causal Modelling of fMRI data, we found general changes in network connections reflected in altered input nodes and endogenous connections when comparing the early and fast learning session to the late and slow learning session...
November 15, 2015: NeuroImage
C Gallea, M Balas, E Bertasi, R Valabregue, D García-Lorenzo, D Coynel, C Bonnet, D Grabli, M Pélégrini-Issac, J Doyon, H Benali, E Roze, M Vidailhet, S Lehericy
Sensorimotor representations of movements are created in the sensorimotor network through repeated practice to support successful and effortless performance. Writer's cramp (WC) is a disorder acquired through extensive practice of finger movements, and it is likely associated with the abnormal acquisition of sensorimotor representations. We investigated (i) the activation and connectivity changes in the brain network supporting the acquisition of sensorimotor representations of finger sequences in patients with WC and (ii) the link between these changes and consolidation of motor performance 24 h after the initial practice...
2015: NeuroImage: Clinical
Marzio Gerbella, Elena Borra, Chiara Mangiaracina, Stefano Rozzi, Giuseppe Luppino
Corticostriatal projections from the primate cortical motor areas partially overlap in different zones of a large postcommissural putaminal sector designated as "motor" putamen. These zones are at the origin of parallel basal ganglia-thalamocortical subloops involved in modulating the cortical motor output. However, it is still largely unknown how parietal and prefrontal areas, connected to premotor areas, and involved in controlling higher order aspects of motor control, project to the basal ganglia. Based on tracer injections at the cortical level, we analyzed the corticostriatal projections of the macaque hand-related ventrolateral prefrontal, ventral premotor, and inferior parietal areas forming a network for controlling purposeful hand actions (lateral grasping network)...
July 2016: Cerebral Cortex
Imis Dogan, Claudia R Eickhoff, Peter T Fox, Angela R Laird, Jörg B Schulz, Simon B Eickhoff, Kathrin Reetz
Huntington's disease (HD) is a progressive neurodegenerative disorder characterized by a complex neuropsychiatric phenotype. In a recent meta-analysis we identified core regions of consistent neurodegeneration in premanifest HD in the striatum and middle occipital gyrus (MOG). For early manifest HD convergent evidence of atrophy was most prominent in the striatum, motor cortex (M1) and inferior frontal junction (IFJ). The aim of the present study was to functionally characterize this topography of brain atrophy and to investigate differential connectivity patterns formed by consistent cortico-striatal atrophy regions in HD...
2015: NeuroImage: Clinical
J Jimenez-Martin, L Blanco-Lezcano, M E González-Fraguela, M-L Díaz-Hung, T Serrano-Sánchez, J L Almenares, L Francis-Turner
Early degeneration of pedunculopontine nucleus (PPN) is considered part of changes that characterize premotor stages of Parkinson's disease (PD). In this paper, the effects of unilateral neurotoxic lesion of the PPN in motor execution and in the development of oxidative stress events in striatal and nigral tissues in rats were evaluated. The motor performance was assessed using the beam test (BT) and the cylinder test (CT). Nigral and striatal redox balance, was studied by means of biochemical indicators such as malondialdehyde (MDA), nitric oxide (NO) and the catalase enzymatic activity (CAT EA)...
March 19, 2015: Neuroscience
Jochen Michely, Lukas J Volz, Michael T Barbe, Felix Hoffstaedter, Shivakumar Viswanathan, Lars Timmermann, Simon B Eickhoff, Gereon R Fink, Christian Grefkes
Although characteristic motor symptoms of Parkinson's disease such as bradykinesia typically improve under dopaminergic medication, deficits in higher motor control are less responsive. We here investigated the dopaminergic modulation of network dynamics underlying basic motor performance, i.e. finger tapping, and higher motor control, i.e. internally and externally cued movement preparation and selection. Twelve patients, assessed ON and OFF medication, and 12 age-matched healthy subjects underwent functional magnetic resonance imaging...
March 2015: Brain: a Journal of Neurology
Rick C Helmich, Avner Thaler, Bart F L van Nuenen, Tanya Gurevich, Anat Mirelman, Karen S Marder, Susan Bressman, Avi Orr-Urtreger, Nir Giladi, Bastiaan R Bloem, Ivan Toni
OBJECTIVE: We investigated system-level corticostriatal changes in a human model of premotor Parkinson disease (PD), i.e., healthy carriers of the G2019S LRRK2 mutation that is associated with a markedly increased, age-dependent risk of developing PD. METHODS: We compared 37 asymptomatic LRRK2 G2019S mutation carriers (age range 30-78 years) with 32 matched, asymptomatic nonmutation carriers (age range 30-74 years). Using fMRI, we tested the hypothesis that corticostriatal connectivity in premotor PD shifts from severely affected to less affected striatal subregions, as shown previously in symptomatic PD...
January 27, 2015: Neurology
Sarah E Henderson, Ana I Vallejo, Benjamin A Ely, Guoxin Kang, Amy Krain Roy, Daniel S Pine, Emily R Stern, Vilma Gabbay
Deficits in emotion processing, a known clinical feature of major depressive disorder (MDD), have been widely investigated using emotional face paradigms and neuroimaging. However, most studies have not accounted for the high inter-subject variability of symptom severity. Similarly, only sparse research has focused on MDD in adolescence, early in the course of the illness. Here we sought to investigate neural responses to emotional faces using both categorical and dimensional analyses with a focus on anhedonia, a core symptom of MDD associated with poor outcomes...
December 30, 2014: Psychiatry Research
Eva M Müller-Oehring, Edith V Sullivan, Adolf Pfefferbaum, Neng C Huang, Kathleen L Poston, Helen M Bronte-Stewart, Tilman Schulte
Parkinson's disease (PD) is associated with abnormal synchronization in basal ganglia-thalamo-cortical loops. We tested whether early PD patients without demonstrable cognitive impairment exhibit abnormal modulation of functional connectivity at rest, while engaged in a task, or both. PD and healthy controls underwent two functional MRI scans: a resting-state scan and a Stroop Match-to-Sample task scan. Rest-task modulation of basal ganglia (BG) connectivity was tested using seed-to-voxel connectivity analysis with task and rest time series as conditions...
September 2015: Brain Imaging and Behavior
Claudine Habak, Anne Noreau, Atsuko Nagano-Saito, Beatriz Mejía-Constaín, Clotilde Degroot, Antonio P Strafella, Sylvain Chouinard, Anne-Louise Lafontaine, Guy A Rouleau, Oury Monchi
Parkinson's disease is a neurodegenerative condition that affects motor function along with a wide range of cognitive domains, including executive function. The hallmark of the pathology is its significant loss of nigrostriatal dopamine, which is necessary for the cortico-striatal interactions that underlie executive control. Striatal dopamine reuptake is mediated by the SLC6A3 gene (formerly named DAT1) and its polymorphisms, which have been largely overlooked in Parkinson's disease. Thirty patients (ages 53-68 years; 19 males, 11 females) at early stages of Parkinson's disease, were genotyped according to a 9-repeat (9R) or 10-repeat (10R) allele on the SLC6A3/DAT1 gene...
November 2014: Brain: a Journal of Neurology
Ming-Kai Pan, Chun-Hwei Tai, Wen-Chuan Liu, Ju-Chun Pei, Wen-Sung Lai, Chung-Chin Kuo
Parkinson's disease (PD) is the most prevalent hypokinetic movement disorder, and symptomatic PD pathogenesis has been ascribed to imbalances between the direct and indirect pathways in the basal ganglia circuitry. Here, we applied glutamate receptor blockers to the subthalamic nucleus (STN) of parkinsonian rats and evaluated locomotor behaviors via single-unit and local-field recordings. Using this model, we found that inhibition of NMDAergic cortico-subthalamic transmission ameliorates parkinsonian motor deficits without eliciting any vivid turning behavior and abolishes electrophysiological abnormalities, including excessive subthalamic bursts, cortico-subthalamic synchronization, and in situ beta synchronization in both the motor cortex and STN...
October 2014: Journal of Clinical Investigation
Dardo Tomasi, Gene-Jack Wang, Ruiliang Wang, Elisabeth C Caparelli, Jean Logan, Nora D Volkow
Cocaine, through its activation of dopamine (DA) signaling, usurps pathways that process natural rewards. However, the extent to which there is overlap between the networks that process natural and drug rewards and whether DA signaling associated with cocaine abuse influences these networks have not been investigated in humans. We measured brain activation responses to food and cocaine cues with fMRI, and D2/D3 receptors in the striatum with [11C]raclopride and Positron emission tomography in 20 active cocaine abusers...
January 2015: Human Brain Mapping
Julien Vezoli, Kwamivi Dzahini, Nicolas Costes, Charles R E Wilson, Karim Fifel, Howard M Cooper, Henry Kennedy, Emmanuel Procyk
The delayed appearance of motor symptoms in PD poses a crucial challenge for early detection of the disease. We measured the binding potential of the selective dopamine active transporter (DAT) radiotracer [(11)C]PE2I in MPTP-treated macaque monkeys, thus establishing a detailed profile of the nigrostriatal DA status following MPTP intoxication and its relation to induced motor and non-motor symptoms. Clinical score and cognitive performance were followed throughout the study. We measured longitudinally in vivo the non-displaceable binding potential to DAT in premotor, motor-recovered (i...
November 15, 2014: NeuroImage
Maria Luisa Mandelli, Eduardo Caverzasi, Richard J Binney, Maya L Henry, Iryna Lobach, Nikolas Block, Bagrat Amirbekian, Nina Dronkers, Bruce L Miller, Roland G Henry, Maria Luisa Gorno-Tempini
In primary progressive aphasia (PPA), speech and language difficulties are caused by neurodegeneration of specific brain networks. In the nonfluent/agrammatic variant (nfvPPA), motor speech and grammatical deficits are associated with atrophy in a left fronto-insular-striatal network previously implicated in speech production. In vivo dissection of the crossing white matter (WM) tracts within this "speech production network" is complex and has rarely been performed in health or in PPA. We hypothesized that damage to these tracts would be specific to nfvPPA and would correlate with differential aspects of the patients' fluency abilities...
July 16, 2014: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Tao Wu, Jun Liu, Hejia Zhang, Mark Hallett, Zheng Zheng, Piu Chan
We investigated neural correlates when attending to a movement that could be made automatically in healthy subjects and Parkinson's disease (PD) patients. Subjects practiced a visuomotor association task until they could perform it automatically, and then directed their attention back to the automated task. Functional MRI was obtained during the early-learning, automatic stage, and when re-attending. In controls, attention to automatic movement induced more activation in the dorsolateral prefrontal cortex (DLPFC), anterior cingulate cortex, and rostral supplementary motor area...
October 2015: Cerebral Cortex
T C Booth, M Nathan, A D Waldman, A-M Quigley, A H Schapira, J Buscombe
The functional imaging technique most widely used in European clinics to differentiate a true parkinsonian syndrome from vascular parkinsonism, drug-induced changes, or essential tremor is dopamine-transporter SPECT. This technique commonly reports dopamine-transporter function, with decreasing striatal uptake demonstrating increasingly severe disease. The strength of dopamine-transporter SPECT is that nigrostriatal degeneration is observed in both clinically inconclusive parkinsonism and early, even premotor, disease...
February 2015: AJNR. American Journal of Neuroradiology
K R Lohse, K Wadden, L A Boyd, N J Hodges
In this systematic review and meta-analysis, we explore how the time scale of practice affects patterns of brain activity associated with motor skill acquisition. Fifty-eight studies that involved skill learning with healthy participants (117 contrasts) met inclusion criteria. Two meta-contrasts were coded: decreases: peak coordinates that showed decreases in brain activity over time; increases: peak coordinates that showed increases in activity over time. Studies were grouped by practice time scale: short (≤1 h; 25 studies), medium (>1 and ≤24 h; 18 studies), and long (>24h to 5 weeks; 17 studies)...
July 2014: Neuropsychologia
Martin Martinez, Federico Villagra, Francis Loayza, Marta Vidorreta, Gonzalo Arrondo, Elkin Luis, Javier Diaz, Mikel Echeverria, Maria A Fernandez-Seara, Maria A Pastor
Repetitive and alternating lower limb movements are a specific component of human gait. Due to technical challenges, the neural mechanisms underlying such movements have not been previously studied with functional magnetic resonance imaging. In this study, we present a novel treadmill device employed to investigate the kinematics and the brain activation patterns involved in alternating and repetitive movements of the lower limbs. Once inside the scanner, 19 healthy subjects were guided by two visual cues and instructed to perform a motor task which involved repetitive and alternating movements of both lower limbs while selecting their individual comfortable amplitude on the treadmill...
May 2014: IEEE Transactions on Medical Imaging
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