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  1. Medical Definition of ventral tegmental area. : an area of the midbrain lying adjacent to the substantia nigra that contains the cell bodies of dopaminergic neurons projecting especially to the nucleus accumbens, amygdala, and olfactory tubercle as part of the mesolimbic system The critical circuit in the brain that underlies reward and ...

  2. Ventral tegmental area (VTA) - definition. a midbrain structure that is rich in dopamine neurons. The VTA is part of the mesolimbic dopamine pathway and an important part of the "reward system." Learn more: 2-Minute Neuroscience: Ventral Tegmental Area. Know Your Brain: Ventral Tegmental Area. Know Your Brain: Reward System

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  4. The ventral tegmental area. The primary role of the ventral tegmental area (VTA) is the assessment of need. The VTA processes information to ensure satisfaction; it then forwards this information to the nucleus accumbens (NA) using the neurotransmitter dopamine. If there is an increase in dopamine in the VTA there is a concurrent increase in ...

  5. Apr 29, 2013 · VENTRAL TEGMENTAL AREA. a region inside the midbrain ventral onto the periaqueductal gray and the dorsal to the substantial nigra. It makes up a portion of the limbic system, carrying dopaminergic neurons to the mesolimbic and mesocortical system. VENTRAL TEGMENTAL AREA: "The ventral tegmental area can be viewed on several pages in your ...

  6. Dec 23, 2014 · The ventral tegmental area, or VTA, is in the midbrain, situated adjacent to the substantia nigra. Although it contains several different types of neurons, it is primarily characterized by its dopaminergic neurons, which project from the VTA throughout the brain. The VTA is considered an integral part of a network of structures, together known ...

    • Anatomy
    • Limbic Loop
    • CA3 Loop
    • Reward System
    • Ventral Tegmental Area Clinical Relevance

    Neurobiologists have often had great difficulty distinguishing the VTA in humans and other primate brains from the substantia nigra (SN) and surrounding nuclei. Originally, the ventral tegmentum was designated as a ‘nucleus,’ but over time ‘area’ became the more appropriate term used because of the heterogeneous cytoarchitectonicfeatures of the region and the lack of clear borders that separate it from adjacent regions.

    The “limbic loop” is very similar to the direct pathway motor loop of the basal ganglia. In both systems, there are major excitatory inputs from the cortex to the striatum (accumbens nucleus), the midbrain project neuromodulatory dopamine neurons to the striatum, the striatum makes internuclear connections to the pallidum, and the pallidum has outputs to the thalamus, which projects to the cortex, thus completing the loop. The limbic loop is distinguished from the motor loop by the source and nature of the cortical input, the division of the striatum and pallidum that process the input, the source of the dopaminergic neurons form the midbrain, and the thalamic target of the pallidal output.

    Linking context to reward is important for reward seeking. In 2011, a group of researchers documented a VTA-CA3 loopthat uses the lateral septum as an intermediary. They used a pseudo-rabies virus (PRV) as a transsynaptic tracer, and injected it into the VTA. They found that unilateral injection into the VTA resulted in bilateral PRV labeling in CA3 beginning 48 hours after injection. Lesions of the caudodorsal lateral septum (cd-LS) prior to VTA PRV injection resulted in significantly less PRV labeled neurons in CA3. Theta wave stimulation of CA3 resulted in increased firing rates for dopamine cells in the VTA, and decreased firing rates for GABAneurons in the VTA. The identity of VTA neurons was confirmed by neurobiotin™ labeling of the recording neuron, and then histological staining for tyrosine hydroxylase (TH). Temporary inactivation of CA3 via GABA agonists prevented context induced reinstatement of lever pressing for intravenous cocaine. The authors propose a functional circ...

    The dopamine reward circuitry in the human brain involves two projection systems from the ventral midbrain to the nucleus accumbens-olfactory tubercle complex. First, the posteromedial VTA and central linear raphe cells selectively project to the ventromedial striatum, which includes the medial olfactory tubercle and the medial NAC shell. Second, the lateral VTA projects largely to the ventrolateral striatum, which includes the NAC core, the medial NAC shell, and the lateral olfactory tubercle. These pathways are called the meso-ventromedial and the meso-ventrolateral striatal dopamine systems, respectively. The medial projection system is important in the regulation of arousal characterized by affect and drive and plays a different role in goal-directed behavior than the lateral projection system. Unlike the lateral part, the medial one is activated not by rewarding but by noxious stimuli. Normally, the dopaminergic neurons are only phasically active. When they are excited, they fi...

    Disorders

    The dopaminergic neurons of the substantia nigra and the ventral tegmental area of the midbrain project to the dorsolateral caudate/putamen and to the ventromedially located nucleus accumbens, respectively, establishing the mesostriatal and the mesolimbic pathways. The close proximity of these two pathways causes them to be grouped together under dopaminergic projections. Several disorders result from the disruption of these two pathways: schizophrenia, Parkinson’s disease, and attention defi...

    Drug Addiction

    The nucleus accumbens and the ventral tegmentum are the primary sites where addictive drugs act. The following are commonly considered to be addictive: heroin, cocaine, alcohol, opiates, nicotine, amphetamine, and their synthetic analogs. These drugs alter the neuromodulatory influence of dopamine on the processing of reinforcement signals by prolonging the action of dopamine in the nucleus accumbens or by stimulating the activation of neurons there and also in the VTA. The most common drugs...

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