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hyperdirect pathway

Athan Spiros, Patrick Roberts, Hugo Geerts
Despite new insights into the pathophysiology of schizophrenia and clinical trials with highly selective drugs, no new therapeutic breakthroughs have been identified. We present a semi-mechanistic Quantitative Systems Pharmacology (QSP) computer model of a biophysically realistic cortical-striatal-thalamo-cortical loop. The model incorporates the direct, indirect and hyperdirect pathway of the basal ganglia and CNS drug targets that modulate neuronal firing, based on preclinical data about their localization and coupling to voltage-gated ion channels...
February 2017: European Neuropsychopharmacology: the Journal of the European College of Neuropsychopharmacology
Marcus L F Janssen, Yasin Temel, Claire Delaville, Daphne G M Zwartjes, Tjitske Heida, Philippe De Deurwaerdère, Veerle Visser-Vandewalle, Abdelhamid Benazzouz
The subthalamic nucleus (STN) receives monosynaptic glutamatergic afferents from different areas of the cortex, known as the "hyperdirect" pathway. The STN has been divided into three distinct subdivisions, motor, limbic, and associative parts in line with the concept of parallel information processing. The extent to which the parallel information processing coming from distinct cortical areas overlaps in the different territories of the STN is still a matter of debate and the proposed role of dopaminergic neurons in maintaining the coherence of responses to cortical inputs in each territory is not documented...
December 24, 2016: Brain Structure & Function
Adam R Aron, Damian M Herz, Peter Brown, Birte U Forstmann, Kareem Zaghloul
The subthalamic nucleus (STN) of the basal ganglia appears to have a potent role in action and cognition. Anatomical and imaging studies show that different frontal cortical areas directly project to the STN via so-called hyperdirect pathways. This review reports some of the latest findings about such circuits, including simultaneous recordings from cortex and the STN in humans, single-unit recordings in humans, high-resolution fMRI, and neurocomputational modeling. We argue that a major function of the STN is to broadly pause behavior and cognition when stop signals, conflict signals, or surprise signals occur, and that the fronto-STN circuits for doing this, at least for stopping and conflict, are dissociable anatomically and in terms of their spectral reactivity...
November 9, 2016: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Zack Blumenfeld, Mandy Miller Koop, Thomas E Prieto, Lauren A Shreve, Anca Velisar, Emma J Quinn, Megan H Trager, Helen Brontë-Stewart
BACKGROUND: The objective of this study was to investigate the hypothesis that attenuation of subthalamic nucleus (STN) alpha-/beta-band oscillations is causal to improvement in bradykinesia. METHODS: STN local field potentials from a sensing neurostimulator (Activa(®) PC+S; Medtronic, Inc.) and kinematics from wearable sensors were recorded simultaneously during 60- and 140-Hz deep brain stimulation (DBS) in 9 freely moving PD subjects (15 STNs) performing repetitive wrist flexion-extension...
November 8, 2016: Movement Disorders: Official Journal of the Movement Disorder Society
Isabelle Massat, Hichem Slama, Thomas Villemonteix, Alison Mary, Simon Baijot, Ariadna Albajara Sáenz, Danièle Balériaux, Thierry Metens, Martin Kavec, Philippe Peigneux
OBJECTIVES: Hypo/reduced activity in motor response inhibition (RI) cerebral networks was recently proposed as a promising specific neurobiological marker of Attention Deficit/Hyperactivity Disorder (ADHD). Before adopting such a pattern as a key diagnosis tool, we aim to replicate in an independent study the mechanisms underlying reduced RI-related activity in ADHD, after controlling for potentially confounding effects. METHODS: In this fMRI study, we investigated the neural networks mediating successful and failed motor RI in children with ADHD and typically developing children (TDC) using the stop signal task (SST) paradigm...
September 20, 2016: World Journal of Biological Psychiatry
Mikkel V Petersen, Torben E Lund, Niels Sunde, Jesper Frandsen, Frederikke Rosendal, Niels Juul, Karen Østergaard
OBJECTIVE Diffusion-weighted MRI (DWI) and tractography allows noninvasive mapping of the structural connections of the brain, and may provide important information for neurosurgical planning. The hyperdirect pathway, connecting the subthalamic nucleus (STN) with the motor cortex, is assumed to play a key role in mediating the effects of deep brain stimulation (DBS), which is an effective but poorly understood treatment for Parkinson disease. This study aimed to apply recent methodological advances in DWI acquisition and analysis to the delineation of the hyperdirect pathway in patients with Parkinson disease selected for surgery...
July 8, 2016: Journal of Neurosurgery
Birgit R Plantinga, Alard Roebroeck, Valentin G Kemper, Kâmil Uludağ, Maartje Melse, Jürgen Mai, Mark L Kuijf, Andreas Herrler, Ali Jahanshahi, Bart M Ter Haar Romeny, Yasin Temel
INTRODUCTION: The subthalamic nucleus, substantia nigra, and globus pallidus, three nuclei of the human basal ganglia, play an important role in motor, associative, and limbic processing. The network of the basal ganglia is generally characterized by a direct, indirect, and hyperdirect pathway. This study aims to investigate the mesoscopic nature of these connections between the subthalamic nucleus, substantia nigra, and globus pallidus and their surrounding structures. METHODS: A human post mortem brain specimen including the substantia nigra, subthalamic nucleus, and globus pallidus was scanned on a 7 T MRI scanner...
2016: Frontiers in Neuroanatomy
Ashwini Oswal, Martijn Beudel, Ludvic Zrinzo, Patricia Limousin, Marwan Hariz, Tom Foltynie, Vladimir Litvak, Peter Brown
Chronic dopamine depletion in Parkinson's disease leads to progressive motor and cognitive impairment, which is associated with the emergence of characteristic patterns of synchronous oscillatory activity within cortico-basal-ganglia circuits. Deep brain stimulation of the subthalamic nucleus is an effective treatment for Parkinson's disease, but its influence on synchronous activity in cortico-basal-ganglia loops remains to be fully characterized. Here, we demonstrate that deep brain stimulation selectively suppresses certain spatially and spectrally segregated resting state subthalamic nucleus-cortical networks...
May 2016: Brain: a Journal of Neurology
Alia Tewari, Rachna Jog, Mandar S Jog
The striatum and the subthalamic nucleus (STN) are two separate input structures into the basal ganglia (BG). Accordingly, research to date has primarily focused on the distinct roles of these structures in motor control and cognition, often through investigation of Parkinson's disease (PD). Both structures are divided into sensorimotor, associative, and limbic subdivisions based on cortical connectivity. The more recent discovery of the STN as an input structure into the BG drives comparison of these two structures and their respective roles in cognition and motor control...
2016: Frontiers in Systems Neuroscience
Josué M Avecillas-Chasin, Fernando Rascón-Ramírez, Juan A Barcia
The cortico-basal ganglia and corticothalamic projections have been extensively studied in the context of neurological and psychiatric disorders. Deep brain stimulation (DBS) is known to modulate many of these pathways to produce the desired clinical effect. The aim of this work is to describe the anatomy of the main circuits of the basal ganglia using tractography in a surgical planning station. We used imaging studies of 20 patients who underwent DBS for movement and psychiatric disorders. We segmented the putamen, caudate nucleus (CN), thalamus, and subthalamic nucleus (STN), and we also segmented the cortical areas connected with these subcortical areas...
May 2016: Clinical Anatomy
Chiara Baston, Mauro Ursino
Basal Ganglia (BG) are implied in many motor and cognitive tasks, such as action selection, and have a central role in many pathologies, primarily Parkinson Disease. In the present work, we use a recently developed biologically inspired BG model to analyze how the dopamine (DA) level can affect the temporal response during action selection, and the capacity to learn new actions following rewards and punishments. The model incorporates the 3 main pathways (direct, indirect and hyperdirect) working in BG functioning...
August 2015: Conference Proceedings: Annual International Conference of the IEEE Engineering in Medicine and Biology Society
Chiara Baston, Mauro Ursino
The basal ganglia (BG) are a subcortical structure implicated in action selection. The aim of this work is to present a new cognitive neuroscience model of the BG, which aspires to represent a parsimonious balance between simplicity and completeness. The model includes the 3 main pathways operating in the BG circuitry, that is, the direct (Go), indirect (NoGo), and hyperdirect pathways. The main original aspects, compared with previous models, are the use of a two-term Hebb rule to train synapses in the striatum, based exclusively on neuronal activity changes caused by dopamine peaks or dips, and the role of the cholinergic interneurons (affected by dopamine themselves) during learning...
2015: Computational Intelligence and Neuroscience
Kyle Dunovan, Brighid Lynch, Tara Molesworth, Timothy Verstynen
The architecture of corticobasal ganglia pathways allows for many routes to inhibit a planned action: the hyperdirect pathway performs fast action cancellation and the indirect pathway competitively constrains execution signals from the direct pathway. We present a novel model, principled off of basal ganglia circuitry, that differentiates control dynamics of reactive stopping from intrinsic no-go decisions. Using a nested diffusion model, we show how reactive braking depends on the state of an execution process...
2015: ELife
Stella M Papa, Thomas Wichmann
No abstract text is available yet for this article.
June 2015: Movement Disorders: Official Journal of the Movement Disorder Society
Joshua W Callahan, Elizabeth D Abercrombie
KEY POINTS: Neural synchrony between the subthalamic nucleus (STN) and cortex is critical for proper information processing in basal ganglia circuits. Using in vivo extracellular recordings in urethane-anaesthetized mice, we demonstrate that single units and local field potentials from the STN exhibit oscillatory entrainment to low-frequency (0.5-4 Hz) rhythms when the cortex is in a synchronized state. Here we report novel findings in the R6/2 transgenic mouse model of Huntington's disease (HD) by demonstrating that STN activity is reduced and less phase-locked to cortical low-frequency oscillations...
August 15, 2015: Journal of Physiology
Javier Baladron, Fred H Hamker
We introduce a spiking neural network of the basal ganglia capable of learning stimulus-action associations. We model learning in the three major basal ganglia pathways, direct, indirect and hyperdirect, by spike time dependent learning and considering the amount of dopamine available (reward). Moreover, we allow to learn a cortico-thalamic pathway that bypasses the basal ganglia. As a result the system develops new functionalities for the different basal ganglia pathways: The direct pathway selects actions by disinhibiting the thalamus, the hyperdirect one suppresses alternatives and the indirect pathway learns to inhibit common mistakes...
July 2015: Neural Networks: the Official Journal of the International Neural Network Society
Christian Ebner, Henning Schroll, Gesche Winther, Michael Niedeggen, Fred H Hamker
How the brain decides which information to process 'consciously' has been debated over for decades without a simple explanation at hand. While most experiments manipulate the perceptual energy of presented stimuli, the distractor-induced blindness task is a prototypical paradigm to investigate gating of information into consciousness without or with only minor visual manipulation. In this paradigm, subjects are asked to report intervals of coherent dot motion in a rapid serial visual presentation (RSVP) stream, whenever these are preceded by a particular color stimulus in a different RSVP stream...
September 2015: Consciousness and Cognition
Henning Schroll, Christian Beste, Fred H Hamker
Huntington's disease (HD) is a hereditary neurodegenerative disease of the basal ganglia that causes severe motor, cognitive and emotional dysfunctions. In the human basal ganglia, these dysfunctions are accompanied by a loss of striatal medium spiny neurons, dysfunctions of the subthalamic nucleus and globus pallidus, and changes in dopamine receptor binding. Here, we used a neuro-computational model to investigate which of these basal ganglia dysfunctions can explain patients' deficits in different stimulus-response learning paradigms...
May 2015: European Journal of Neuroscience
Joshua W Callahan, Elizabeth D Abercrombie
Huntington's disease (HD) is an autosomal dominant neurodegenerative disorder that results in motor, cognitive and psychiatric abnormalities. Dysfunction in neuronal processing between the cortex and the basal ganglia is fundamental to the onset and progression of the HD phenotype. The corticosubthalamic hyperdirect pathway plays a crucial role in motor selection and blockade of neuronal activity in the subthalamic nucleus (STN) results in hyperkinetic movement abnormalities, similar to the motor symptoms associated with HD...
June 2015: Neurobiology of Disease
Wei Wei, Jonathan E Rubin, Xiao-Jing Wang
The basal ganglia (BG) play an important role in motor control, reinforcement learning, and perceptual decision making. Modeling and experimental evidence suggest that, in a speed-accuracy tradeoff, the corticostriatal pathway can adaptively adjust a decision threshold (the amount of information needed to make a choice). In this study, we go beyond the focus of previous works on the direct and hyperdirect pathways to examine the contribution of the indirect pathway of the BG system to decision making in a biophysically based spiking network model...
March 4, 2015: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
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