====== Nucleus accumbens ======

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The [[nucleus]] accumbens (NAcc), also known as the accumbens nucleus or as the nucleus accumbens septi (Latin for nucleus adjacent to the septum) is a [[region]] in the basal [[forebrain]] rostral to the [[preoptic area]] of the [[hypothalamus]].

The nucleus accumbens and the [[olfactory tubercle]] collectively form the [[ventral striatum]], which is part of the [[basal ganglia]].

Each cerebral hemisphere has its own nucleus accumbens. It is located where the head of the [[caudate nucleus]] and the anterior portion of the [[putamen]] meet just lateral to the [[septum pellucidum]]. 



===== Function =====
The nucleus accumbens can be divided into two structures—the nucleus accumbens core and the nucleus accumbens shell. These structures have different morphology and function.
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[[Cocaine]] use followed by [[withdrawal]] induces [[synaptic plasticity]] in the [[nucleus accumbens]] (NAc), which are thought to underlie subsequent drug-seeking behaviors and relapse. Previous studies suggest that [[cocaine]]-induced synaptic changes depend on [[acid-sensing ion channels]] (ASICs). 
Gupta et al. investigated the potential involvement of [[carbonic anhydrase]] 4 (CA4), an extracellular pH-buffering enzyme. 
They examined the effects of [[CA4]] in [[mice]] on ASIC-mediated synaptic transmission in [[medium spiny neuron]]s (MSNs) in NAc, as well as on cocaine-induced synaptic changes and behavior. 
They found that CA4 is expressed in the NAc and present in [[synaptosome]]s. Disrupting CA4 either globally, or locally, increased ASIC-mediated synaptic currents in NAc MSNs and protected against [[cocaine withdrawal]]-induced changes in [[synapse]]s and cocaine-seeking behavior. These findings raise the possibility that CA4 might be a previously unidentified therapeutic target for addiction and relapse
((Gupta SC, Ghobbeh A, Taugher-Hebl RJ, Fan R, Hardie JB, LaLumiere RT, Wemmie JA. [[Carbonic anhydrase 4]] disruption decreases synaptic and behavioral adaptations induced by [[cocaine withdrawal]]. Sci Adv. 2022 Nov 18;8(46):eabq5058. doi: 10.1126/sciadv.abq5058. Epub 2022 Nov 16. PMID: 36383659.)).
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Research has indicated the nucleus accumbens has an important role in pleasure including laughter, reward, and reinforcement learning, as well as fear, aggression, impulsivity, addiction, and the placebo effect.
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Previous imaging studies independently highlighted the role of the anterior [[thalamus]] (ANT) and [[nucleus accumbens]] (NAcc) in successful [[memory]] retrieval. While these findings accord with theoretical models, the precise temporal, oscillatory and network dynamics as well as the interplay between the NAcc and ANT in successfully retrieving information from long-term memory are largely unknown. 

The University of [[Hamburg]], [[Lübeck]] and [[Magdeburg]] in [[Germany]] addressed this issue by recording intracranial [[electroencephalography]] in human [[epilepsy]] patients from the NAcc (n = 5) and ANT (n = 4) during an old/new [[recognition]] test. 

The findings demonstrate that differences in event-related potentials between correctly classified old (i.e., studied) and new (i.e., unstudied) images emerged in the NAcc and ANT already between 200 and 600 ms after stimulus onset. Moreover, time-frequency analyses revealed [[theta]] (4-8 Hz) power decreases for old compared to new items in the NAcc and the opposite effect in the ANT. Importantly, [[Granger causality]] analyses revealed a directional communication from ANT to NAcc suggesting that entrainment from ANT drives successful memory retrieval. 

Together, this findings show [[evidence]] for the notion that the NAcc and ANT receive memory signals, and that [[theta]] oscillations may serve as a mechanism to bind these distributed neural assemblies
((Bauch EM, Bunzeck N, Hinrichs H, Schmitt FC, Voges J, Heinze HJ, Zaehle T.
Theta Oscillations underlie Retrieval Success Effects in the Nucleus Accumbens
and anterior Thalamus: evidence from human intracranial recordings. Neurobiol
Learn Mem. 2018 Jul 4. pii: S1074-7427(18)30154-0. doi:
10.1016/j.nlm.2018.07.001. [Epub ahead of print] PubMed PMID: 29981424.
)).

===== Nucleus accumbens deep brain stimulation =====


see [[Nucleus accumbens deep brain stimulation]].