nucleus accumbens


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nu·cle·us ac·cum·'bens

[TA]
the region of fusion between the head of the caudate nucleus and the putamen, covered on its inferior aspect by the olfactory tubercle. Its former name nucleus accumbens septi ("a nucleus leaning against the septum") refers to a medial, hook-shaped expansion of this anteroventral region of the striatum, which curves under the floor of the frontal horn of the lateral ventricle and ascends for some distance into the ventral half of the septal region. Composed of a pars lateralis [TA] (lateral part [TA] or core region [TAalt]) and a pars medialis [TA] (medial part [TA] or shell region [TAalt]).

nucleus accumbens

A limbic nucleus that sits at the ventral head of the striatum, contiguous with the caudate and putamen and adjacent to the olfactory tubercle. The nucleus accumbens is part of the ventral striatum nuclei. Synapses in the nucleus accumbens use dopamine as their neurotransmitter. Increasing the activity of these synapses (i.e., increasing the level of dopamine in the nucleus) leads to a rewarding or pleasurable sensation. This is thought to partly explain the addictive effect of those drugs, such as cocaine and amphetamine, that increase the level of dopamine in the nucleus accumbens.
See also: nucleus
References in periodicals archive ?
The researchers concluded: "Compounds that activate A2A receptors in the nucleus accumbens may open safe therapeutic avenues for treating insomnia, which is one of the most common sleep problems with an estimated prevalence of 10-15 percent in the general population and 30-60 percent in the older population."
Mermelstein, "Measurements of neuron soma size and density in rat dorsal striatum, nucleus accumbens core and nucleus accumbens shell: differences between striatal region and brain hemisphere, but not sex," Neuroscience Letters, vol.
Leao et al., "Role of nucleus accumbens shell neuronal ensembles in context-induced reinstatement of cocaine-seeking," Journal of Neuroscience, vol.
Deep brain stimulation of the nucleus accumbens and the internal capsule in therapeutically refractory Tourette-syndrome.
Amphetamine or cocaine limits the ability of later experience to promote structural plasticity in the neocortex and nucleus accumbens. Proc Natl Acad Sci U S A 2003;100:10523-8.
Effects of methamphetamine and morphine on the dialysate levels of dopamine in the nucleus accumbens of mice
The next time you see an exceptional parent nibbling on an OREO cookie whether it's before the start of an IEP meeting, a clinic appointment, an appeals review, a conference or an interview appreciate that their nucleus accumbens is probably lighting up like a Christmas tree ...
(8,23-25) Previous study demonstrated that melatonin receptors have an antinociceptive activity in pain response; these results showed that melatonin has antinociceptive action by releasing of opioids like peptide in the brain region such as nucleus accumbens. Thus, because of this antinociceptive effect, this hormone could be beneficial in the attenuation of pain due to morphine withdrawal syndrome.
Locomotor sensitization to ethanol impairs NMDA receptor-dependent synaptic plasticity in the nucleus accumbens and increases ethanol self-administration.
Galanin and the nucleus accumbens cells probably aren't the only factors in reducing motivation, Malenka says.
Consistent with reports that found a stimulatory effect of activation of CB1R in the nucleus accumbens, intra-NAcS injections of WIN 55 212-2 (all doses) significantly increased standard chow intake (interaction dose x hour [F.sub.(3,30)] = 4.480; factor dose [F.sub.(3,30)] = 7.511; factor hour [F.sub.(1,30)] = 25.81; p < 0.05) during the first hour of observation, and the effect persisted during the second hour of the behavioral record when a dose of 0.25 nmol was administered (Figure 2).
Microdialysis measurements of METH-induced dopamine release in the nucleus accumbens of rats