Read by QxMD icon Read

Motor circuit disorder

David S Xu, Francisco Ponce
High-frequency deep brain stimulation (DBS) is a neurosurgical procedure that was introduced in the late 1980s for the treatment of movement disorders. It is a reversible, adjustable, and non-ablative therapy that has been used in over 100,000 people worldwide. The surgical procedure used to implant the DBS system, as well as the effects of chronic electrical stimulation, have been shown to be safe and effective through many clinical trials. The ability to therapeutically modulate the motor circuits of the brain in this manner has resulted in consideration of use of this surgical strategy for other neurodegenerative and neuropsychiatric disorders involving non-motor circuits, including appetite, mood, and cognition...
October 14, 2016: Current Alzheimer Research
L I Schmitt, M M Halassa
While localizing sensory and motor deficits is one of the cornerstones of clinical neurology, behavioral and cognitive deficits in psychiatry remain impervious to this approach. In psychiatry, major challenges include the relative subtlety by which neural circuits are perturbed, and the limited understanding of how basic circuit functions relate to thought and behavior. Neurodevelopmental disorders offer a window to addressing the first challenge given their strong genetic underpinnings, which can be linked to biological mechanisms...
October 11, 2016: Molecular Psychiatry
S Aybek, P Vuilleumier
Brain imaging techniques provide unprecedented opportunities to study the neural mechanisms underlying functional neurologic disorder (FND, or conversion disorder), which have long remained a mystery and clinical challenge for physicians, as they arise with no apparent underlying organic disease. One of the first questions addressed by imaging studies concerned whether motor conversion deficits (e.g., hysteric paralysis) represent a form of (perhaps unconscious) simulation, a mere absence of voluntary movement, or more specific disturbances in motor control (such as abnormal inhibition)...
2017: Handbook of Clinical Neurology
Russell G Port, William Gaetz, Luke Bloy, Dah-Jyuu Wang, Lisa Blaskey, Emily S Kuschner, Susan E Levy, Edward S Brodkin, Timothy P L Roberts
Autism spectrum disorder (ASD) is hypothesized to arise from imbalances between excitatory and inhibitory neurotransmission (E/I imbalance). Studies have demonstrated E/I imbalance in individuals with ASD and also corresponding rodent models. One neural process thought to be reliant on E/I balance is gamma-band activity (Gamma), with support arising from observed correlations between motor, as well as visual, Gamma and underlying GABA concentrations in healthy adults. Additionally, decreased Gamma has been observed in ASD individuals and relevant animal models, though the direct relationship between Gamma and GABA concentrations in ASD remains unexplored...
October 1, 2016: Autism Research: Official Journal of the International Society for Autism Research
Xun Yang, Liyuan Hu, Jianguang Zeng, Ying Tan, Bochao Cheng
Specific frontolimbic abnormalities are hypothesized to underlie the etiology of borderline personality disorder (BPD). However, findings from neuroimaging studies were inconsistent. In the current study, we aimed to provide a complete overview of cerebral microstructural alterations in gray matter (GM) of BPD patients. A total of 11 studies were enrolled, comprising 275 BPD patients and 290 healthy controls (HCs). A meta-analysis was conduct to quantitatively estimate regional GM abnormalities in BPD patients using the seed-based d mapping (SDM)...
October 3, 2016: Scientific Reports
Wei-Hsiang Huang, Casey J Guenthner, Jin Xu, Tiffany Nguyen, Lindsay A Schwarz, Alex W Wilkinson, Or Gozani, Howard Y Chang, Mehrdad Shamloo, Liqun Luo
Haploinsufficiency of Retinoic Acid Induced 1 (RAI1) causes Smith-Magenis syndrome (SMS), which is associated with diverse neurodevelopmental and behavioral symptoms as well as obesity. RAI1 encodes a nuclear protein but little is known about its molecular function or the cell types responsible for SMS symptoms. Using genetically engineered mice, we found that Rai1 preferentially occupies DNA regions near active promoters and promotes the expression of a group of genes involved in circuit assembly and neuronal communication...
September 22, 2016: Neuron
Miriam C Klein-Flügge, Steven W Kennerley, Karl Friston, Sven Bestmann
UNLABELLED: Integrating costs and benefits is crucial for optimal decision-making. Although much is known about decisions that involve outcome-related costs (e.g., delay, risk), many of our choices are attached to actions and require an evaluation of the associated motor costs. Yet how the brain incorporates motor costs into choices remains largely unclear. We used human fMRI during choices involving monetary reward and physical effort to identify brain regions that serve as a choice comparator for effort-reward trade-offs...
September 28, 2016: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Najet Serradj, John H Martin
Evidence suggests that motor experience plays a role in shaping development of the corticospinal system and voluntary motor control, which is a key motor function of the system. Here we used a mouse model with conditional forebrain deletion of the gene for EphA4 (Emx1-Cre:EphA4tm2Kldr), which regulates development of the laterality of corticospinal tract (CST). We combined study of Emx1-Cre:EphA4tm2Kldr with unilateral forelimb constraint during development to expand our understanding of experience-dependent CST development from both basic and translational perspectives...
2016: PloS One
Emmanuel Matas, Jörg Bock, Katharina Braun
The development of the brain depends on an individual's nature (genes) and nurture (environments). This interaction between genetic predispositions and environmental events during brain development drives the maturation of functional brain circuits such as sensory, motor, emotional, and complex cognitive pathways. Adverse environmental conditions such as early life stress can interfere with the functional development of emotional and cognitive brain systems and thereby increase the risk of developing psychiatric disorders later in life...
September 27, 2016: Psychopathology
Sebastian Markett, Benjamin Bleek, Martin Reuter, Holger Prüss, Kirsten Richardt, Thilo Müller, J Scott Yaruss, Christian Montag
Idiopathic stuttering is a fluency disorder characterized by impairments during speech production. Deficits in the motor control circuits of the basal ganglia have been implicated in idiopathic stuttering but it is unclear how these impairments relate to the disorder. Previous work has indicated a possible deficiency in motor inhibition in children who stutter. To extend these findings to adults, we designed two experiments to probe executive motor control in people who stutter using manual reaction time tasks that do not rely on speech production...
September 13, 2016: Neuropsychologia
Pranita Nirgudkar, Devin H Taylor, Yuchio Yanagawa, C Fernando Valenzuela
Cerebellar alterations are a hallmark of Fetal Alcohol Spectrum Disorders and are thought to be responsible for deficits in fine motor control, motor learning, balance, and higher cognitive functions. These deficits are, in part, a consequence of dysfunction of cerebellar circuits. Although the effect of developmental ethanol exposure on Purkinje and granule cells has been previously characterized, its actions on other cerebellar neuronal populations are not fully understood. Here, we assessed the impact of repeated ethanol exposure on the number of inhibitory neurons in the cerebellar vermis...
October 6, 2016: Neuroscience Letters
Changzheng Zhang, Peiling Zhou, Tifei Yuan
The cerebellar cholinergic system belongs to the third type of afferent nerve fiber system (after the climbing and mossy fibers), and has important modulatory effects on cerebellar circuits and cerebellar-mediated functions. In this report, we review the cerebellar cholinergic system, including cholinergic origins and innervations, acetylcholine receptor expression and distributions, cholinergic modulations of neuronal firing and synaptic plasticity, the cholinergic role in cerebellar-mediated integral functions, and cholinergic changes during development and aging...
August 25, 2016: Reviews in the Neurosciences
Livia Casarelli, Maurizio Minnei, Mariabernarda Pitzianti, Marco Armando, Maria Pontillo, Stefano Vicari, Augusto Pasini
22q11 Deletion syndrome (22q11DS) is a neurogenetic disorder, resulting from a hemizygous microdeletion on the long arm of chromosome 22. In 22q11DS, the phenotypic expression is highly variable. Approximately one-third of all individuals with 22q11DS develop schizophrenia-like psychotic disorder. Among the genes in the deleted region, catechol-O-methyltransferase (COMT) has a particular relevance for psychiatric disorders: lower COMT enzymatic activity decreases the clearance of dopamine (DA), yielding higher levels of catecholamines in the central nervous system...
October 2016: Psychiatric Genetics
Jorge Guridi, Manuel Alegre
Over the past 10 years, research into the neurophysiology of the basal ganglia has provided new insights into the pathophysiology of movement disorders. The presence of pathological oscillations at specific frequencies has been linked to different signs and symptoms in PD and dystonia, suggesting a new model to explain basal ganglia dysfunction. These advances occurred in parallel with improvements in imaging and neurosurgical techniques, both of which having facilitated the more widespread use of DBS to modulate dysfunctional circuits...
August 22, 2016: Movement Disorders: Official Journal of the Movement Disorder Society
Sriram Jayabal, Lovisa Ljungberg, Alanna J Watt
KEY POINTS: Spinocerebellar ataxia type 6 (SCA6) is a midlife-onset neurodegenerative disease caused by a CACNA1A mutation; CACNA1A is also implicated in cerebellar development. We have previously shown that when disease symptoms are present in midlife in SCA6(84Q/84Q) mice, cerebellar Purkinje cells spike with reduced rate and precision. In contrast, we find that during postnatal development (P10-13), SCA6(84Q/84Q) Purkinje cells spike with elevated rate and precision. Although surplus climbing fibres are linked to ataxia in other mouse models, we found surplus climbing fibre inputs on developing (P10-13) SCA6(84Q/84Q) Purkinje cells when motor deficits were not detected...
August 17, 2016: Journal of Physiology
Stanley N Caroff, E Cabrina Campbell
The development of drugs to treat psychosis is a fascinating nexus for understanding mechanisms underlying disorders of mind and movement. Although the risk of drug-induced extrapyramidal syndromes has been mitigated by the acceptance of less potent dopamine antagonists, expansive marketing and off-label use has increased the number of susceptible people who may be at risk for these neurologic effects. Clinicians need to be familiar with advances in diagnosis and management, which are reviewed herein. A better understanding of drug-induced effects on the motor circuit may improve patient safety, enhance antipsychotic effectiveness, and provide insights into mechanisms underlying antipsychotic activity in parallel brain circuits...
September 2016: Psychiatric Clinics of North America
L Defebvre, P Krystkowiak
Stroke may be associated with different types of movement disorders, such as hyperkinetic syndromes (hemichorea-hemiballism, unilateral asterixis, limb-shaking, dystonia, tremor, myoclonus) and hypokinetic syndromes (especially vascular parkinsonism). However, movement disorders are rare and transient in acute stroke and, as a permanent consequence, are more often delayed. While ischemic and hemorrhagic strokes can happen at any level of the frontal-subcortical motor system, they can be explained most of the time by a dysfunction in the basal ganglia motor circuit...
August 2016: Revue Neurologique
Na-Yeon Jung, Hee Jin Kim, Yeo Jin Kim, Seonwoo Kim, Sang Won Seo, Eun-Joo Kim, Duk L Na
BACKGROUND: Neuropsychiatric symptoms of subcortical vascular dementia (SVaD) are mainly associated with damage to frontal-subcortical circuits and may be similar to symptoms of behavioral variant frontotemporal dementia (bvFTD). The aim of this study was to determine whether the neuropsychiatric manifestations of the Pittsburgh compound B (PiB)-negative SVaD and bvFTD groups differ. METHODS: We compared the Caregiver-Administered Neuropsychiatry Inventory (CGA-NPI) between 48 patients with PiB(-) SVaD and 31 patients with bvFTD...
November 2016: Archives of Gerontology and Geriatrics
Clara Ortega-de San Luis, Alberto Pascual
Glial cell line-derived neurotrophic factor (GDNF) is proposed as a therapeutic tool in Parkinson's disease, addiction-related disorders, and neurodegenerative conditions affecting motor neurons (MNs). Despite the high amount of work about GDNF therapeutic application, the neuronal circuits requiring GDNF trophic support in the brain and spinal cord (SC) are poorly characterized. Here, we defined GDNF and GDNF family receptor-α 1 (GFRα1) expression pattern in the brain and SC of newborn and adult mice. We performed systematic and simultaneous detection of EGFP and LacZ expressing alleles in reporter mice and asked whether modifications of this signaling pathway lead to a significant central nervous system (CNS) alteration...
2016: Frontiers in Neuroanatomy
E P Bello, R Casas-Cordero, G L Galiñanes, E Casey, M A Belluscio, V Rodríguez, D Noaín, M G Murer, M Rubinstein
Motor execution and planning are tightly regulated by dopamine D1 and D2 receptors present in basal ganglia circuits. Although stimulation of D1 receptors is known to enhance motor function, the global effect of D2 receptor (D2R) stimulation or blockade remains highly controversial, with studies showing increasing, decreasing or no changes in motor activity. Moreover, pharmacological and genetic attempts to block or eliminate D2R have led to controversial results that questioned the importance of D2R in motor function...
July 19, 2016: Molecular Psychiatry
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"