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Dopamine tonic phasic

P Leon Brown, Heather Palacorolla, Dana Brady, Katelyn Riegger, Greg I Elmer, Paul D Shepard
: Neurons in the lateral habenula (LHb) are transiently activated by aversive events and have been implicated in associative learning. Functional changes associated with tonic and phasic activation of the LHb are often attributed to a corresponding inhibition of midbrain dopamine (DA) neurons. Activation of GABAergic neurons in the rostromedial tegmental nucleus (RMTg), a region that receives dense projections from the LHb and projects strongly to midbrain monoaminergic nuclei, is believed to underlie the transient inhibition of DA neurons attributed to activation of the LHb...
December 1, 2016: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Kirsten R Müller-Vahl, Gesa Loeber, Alexandra Kotsiari, Linda Müller-Engling, Helge Frieling
Several lines of evidence support a "dopaminergic hypothesis" in the pathophysiology of Gilles de la Tourette syndrome (TS). The aim of this study was to investigate for the first time epigenetic changes in DNA methylation in different dopamine genes in adult patients with TS. We included 51 well characterized adult patients with TS (41 males, 10 females, mean age = 35 ± 12.6 years, range, 18-71 years) and compared results with data from a group of 51 sex- and age-matched healthy controls. Bisulfite sequencing was used to measure peripheral DNA methylation of the dopamine transporter (DAT), the dopamine D2 receptor (DRD2), and the catechol-O-methyltransferase (COMT) genes...
November 12, 2016: Journal of Psychiatric Research
Chiara Volpato, Sami Schiff, Silvia Facchini, Stefano Silvoni, Marianna Cavinato, Francesco Piccione, Angelo Antonini, Niels Birbaumer
Dopamine systems mediate key aspects of reward learning. Parkinson's disease (PD) represents a valuable model to study reward mechanisms because both the disease process and the anti-Parkinson medications influence dopamine neurotransmission. The aim of this pilot study was to investigate whether the level of levodopa differently modulates learning from positive and negative feedback and its electrophysiological correlate, the error related negativity (ERN), in PD. Ten PD patients and ten healthy participants performed a two-stage reinforcement learning task...
2016: Frontiers in Behavioral Neuroscience
Sten Grillner, Brita Robertson
The lamprey belongs to the phylogenetically oldest group of vertebrates that diverged from the mammalian evolutionary line 560 million years ago. A comparison between the lamprey and mammalian basal ganglia establishes a detailed similarity regarding its input from cortex/pallium and thalamus, as well as its intrinsic organisation and projections of the output nuclei. This means that the basal ganglia circuits now present in rodents and primates most likely had evolved already at the dawn of vertebrate evolution...
October 24, 2016: Current Biology: CB
Yoonbae Oh, Cheonho Park, Do Hyoung Kim, Hojin Shin, Yu Min Kang, Mark DeWaele, Jeyeon Lee, Hoon-Ki Min, Charles D Blaha, Kevin Bennet, In Young Kim, Kendall H Lee, Dong Pyo Jang
Dopamine (DA) modulates central neuronal activity through both phasic (second to second) and tonic (minutes to hours) terminal release. Conventional fast-scan cyclic voltammetry (FSCV), in combination with carbon fiber microelectrodes, has been used to measure phasic DA release in vivo by adopting a background subtraction procedure to remove background capacitive currents. However, to-date, measuring tonic changes in DA concentrations using conventional FSCV has been difficult because background capacitive currents are inherently unstable over long recording periods...
October 24, 2016: Analytical Chemistry
Aimee Zisner, Theodore P Beauchaine
Trait impulsivity, which is often defined as a strong preference for immediate over delayed rewards and results in behaviors that are socially inappropriate, maladaptive, and short-sighted, is a predisposing vulnerability to all externalizing spectrum disorders. In contrast, anhedonia is characterized by chronically low motivation and reduced capacity to experience pleasure, and is common to depressive disorders. Although externalizing and depressive disorders have virtually nonoverlapping diagnostic criteria in the fifth edition of the Diagnostic and Statistical Manual of Mental Disorders, heterotypic comorbidity between them is common...
November 2016: Development and Psychopathology
E A Evers, P Stiers, J G Ramaekers
Dopamine plays an important role in goal-directed behavior, through its modulatory influence on striatal neurons. It is unclear whether tonic dopamine levels, which regulate the vigor of acting, interact with the phasic dopamine response to reward that drives instrumental behavior.In a randomized placebo-controlled study in healthy volunteers, we show that methylphenidate, a drug that increases tonic dopamine levels, systematically reduced striatal phasic BOLD responses to gain and loss in a gambling task as measured with fMRI...
September 27, 2016: Social Cognitive and Affective Neuroscience
Simona Scheggi, Miriam Melis, Marta De Felice, Sonia Aroni, Anna Lisa Muntoni, Teresa Pelliccia, Carla Gambarana, Maria Graziella De Montis, Marco Pistis
Depressive disorders cause a substantial burden for the individual and the society. Key depressive symptoms can be modeled in animals and enable the development of novel therapeutic interventions. Chronic unavoidable stress disrupts rats' competence to escape noxious stimuli and self-administer sucrose, configuring a depression model characterized by escape deficit and motivational anhedonia associated to impaired dopaminergic responses to sucrose in the nucleus accumbens shell (NAcS). Repeated treatments that restore these responses also relieve behavioral symptoms...
November 2016: Neuropharmacology
Birgitta Johansson Cahlin, Jan Hedner, Lars Dahlström
Sleep bruxism bears several similarities to restless legs syndrome, and a link to changes in central dopamine activity has been considered in both conditions. The dopamine agonist pramipexole is currently indicated for the symptomatic treatment of restless legs. The effect of pramipexole on sleep bruxism was investigated in subjects with 'probable bruxism' recruited at the Orofacial Pain Clinic. Thirteen patients underwent polysomnographic recordings, including bilateral masseter electromyographic activity...
July 17, 2016: Journal of Sleep Research
Maria A Mikhailova, Caroline E Bass, Valentina P Grinevich, Ann M Chappell, Alex L Deal, Keith D Bonin, Jeff L Weiner, Raul R Gainetdinov, Evgeny A Budygin
Recent optogenetic studies demonstrated that phasic dopamine release in the nucleus accumbens may play a causal role in multiple aspects of natural and drug reward-related behaviors. The role of tonic dopamine release in reward consummatory behavior remains unclear. The current study used a combinatorial viral-mediated gene delivery approach to express ChR2 on mesolimbic dopamine neurons in rats. We used optical activation of this dopamine circuit to mimic tonic dopamine release in the nucleus accumbens and to explore the causal relationship between this form of dopamine signaling within the ventral tegmental area (VTA)-nucleus accumbens projection and consumption of a natural reward...
October 1, 2016: Neuroscience
Anthony A Grace
The dopamine system is unique among the brain's modulatory systems in that it has discrete projections to specific brain regions involved in motor behaviour, cognition and emotion. Dopamine neurons exhibit several activity patterns - including tonic and phasic firing - that are determined by a combination of endogenous pacemaker conductances and regulation by multiple afferent systems. Emerging evidence suggests that disruptions in these regulatory systems may underlie the pathophysiology of several psychiatric disorders, including schizophrenia and depression...
August 2016: Nature Reviews. Neuroscience
Francesco Rigoli, Benjamin Chew, Peter Dayan, Raymond J Dolan
Dopamine plays a key role in motivation. Phasic dopamine response reflects a reinforcement prediction error (RPE), whereas tonic dopamine activity is postulated to represent an average reward that mediates motivational vigor. However, it has been hard to find evidence concerning the neural encoding of average reward that is uncorrupted by influences of RPEs. We circumvented this difficulty in a novel visual search task where we measured participants' button pressing vigor in a context where information (underlying an RPE) about future average reward was provided well before the average reward itself...
September 2016: Journal of Cognitive Neuroscience
Elizabeth N Holly, Christopher O Boyson, Sandra Montagud-Romero, Dirson J Stein, Kyle L Gobrogge, Joseph F DeBold, Klaus A Miczek
UNLABELLED: Intermittent social defeat stress escalates later cocaine self-administration. Reward and stress both activate ventral tegmental area (VTA) dopamine neurons, increasing downstream extracellular dopamine concentration in the medial prefrontal cortex and nucleus accumbens. The stress neuropeptide corticotropin releasing factor (CRF) and its receptors (CRF-R1, CRF-R2) are located in the VTA and influence dopaminergic activity. These experiments explore how CRF release and the activation of its receptors within the VTA both during and after stress influence later cocaine self-administration in rats...
April 6, 2016: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Abigail G Schindler, Marta E Soden, Larry S Zweifel, Jeremy J Clark
UNLABELLED: Alcohol is the most commonly abused substance among adolescents, promoting the development of substance use disorders and compromised decision-making in adulthood. We have previously demonstrated, with a preclinical model in rodents, that adolescent alcohol use results in adult risk-taking behavior that positively correlates with phasic dopamine transmission in response to risky options, but the underlying mechanisms remain unknown. Here, we show that adolescent alcohol use may produce maladaptive decision-making through a disruption in dopamine network dynamics via increased GABAergic transmission within the ventral tegmental area (VTA)...
March 30, 2016: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Yuhong Li, Christoph Lindemann, Matthew J Goddard, Brian I Hyland
UNLABELLED: Midline thalamus is implicated in linking visceral and exteroceptive sensory information with behavior. However, whether neuronal activity is modulated with temporal precision by cues and actions in real time is unknown. Using single-neuron recording and a Pavlovian visual-cue/liquid-reward association task in rats, we discovered phasic responses to sensory cues, appropriately timed to modify information processing in output targets, as well as tonic modulations within and between trials that were differentially reward modulated, which may have distinct arousal functions...
March 23, 2016: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Philippe De Deurwaerdère, Giuseppe Di Giovanni
Since their discovery in the mammalian brain, it has been apparent that serotonin (5-HT) and dopamine (DA) interactions play a key role in normal and abnormal behavior. Therefore, disclosure of this interaction could reveal important insights into the pathogenesis of various neuropsychiatric diseases including schizophrenia, depression and drug addiction or neurological conditions such as Parkinson's disease and Tourette's syndrome. Unfortunately, this interaction remains difficult to study for many reasons, including the rich and widespread innervations of 5-HT and DA in the brain, the plethora of 5-HT receptors and the release of co-transmitters by 5-HT and DA neurons...
March 21, 2016: Progress in Neurobiology
Arif A Hamid, Jeffrey R Pettibone, Omar S Mabrouk, Vaughn L Hetrick, Robert Schmidt, Caitlin M Vander Weele, Robert T Kennedy, Brandon J Aragona, Joshua D Berke
Dopamine cell firing can encode errors in reward prediction, providing a learning signal to guide future behavior. Yet dopamine is also a key modulator of motivation, invigorating current behavior. Existing theories propose that fast (phasic) dopamine fluctuations support learning, whereas much slower (tonic) dopamine changes are involved in motivation. We examined dopamine release in the nucleus accumbens across multiple time scales, using complementary microdialysis and voltammetric methods during adaptive decision-making...
January 2016: Nature Neuroscience
Zev B Rosen, Stephanie Cheung, Steven A Siegelbaum
Dopamine (DA) is required for hippocampal-dependent memory and long-term potentiation (LTP) at CA1 Schaffer collateral (SC) synapses. It is therefore surprising that exogenously applied DA has little effect on SC synapses, but suppresses CA1 perforant path (PP) inputs. To examine DA actions under more physiological conditions, we used optogenetics to release DA from ventral tegmental area inputs to hippocampus. Unlike exogenous DA application, optogenetic release of DA caused a bidirectional, activity-dependent modulation of SC synapses, with no effect on PP inputs...
December 2015: Nature Neuroscience
Rajendra D Badgaiyan, Sampada Sinha, Munawwar Sajjad, David S Wack
It is unclear whether attention deficit hyperactive disorder (ADHD) is a hypodopaminergic or hyperdopaminergic condition. Different sets of data suggest either hyperactive or hypoactive dopamine system. Since indirect methods used in earlier studies have arrived at contradictory conclusions, we directly measured the tonic and phasic release of dopamine in ADHD volunteers. The tonic release in ADHD and healthy control volunteers was measured and compared using dynamic molecular imaging technique. The phasic release during performance of Eriksen's flanker task was measured in the two groups using single scan dynamic molecular imaging technique...
2015: PloS One
Weidong Le, Lifen Zhang, Wenjie Xie, Song Li, John A Dani
Midbrain dopamine (DA) neurons are involved in cognition, control of motor activity, and emotion-related behaviors. Degeneration of DA neurons particularly in the substantia nigra is a hallmark of Parkinson's disease. The homeobox transcription factor, Pitx3, plays a critical role in the development, function, and maintenance of midbrain DA neurons. We found that in young adult Pitx3-null mice, Pitx3(-/-), there was decreased tyrosine hydroxylase staining, indicating a loss of DA neurons particularly in the substantia nigra...
December 2015: Neurobiology of Aging
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