Nucleus accumbens and Parkinsons disease: Exploring the role of Mavridis atrophy

Introduction The human nucleus accumbens (NA), a limbic-motor interface, plays an important role in motivation and emotional processes and is involved in some of the most disabling neuropsychiatric disorders such as Parkinson’s disease (PD). PD, a common disorder of dopamine (DA) dysfunction, is characterised by motor, psychiatric and autonomic symptoms. Mavridis’ atrophy (MA) is called the parkinsonism-related shrinkage of the human NA. The purpose of this article was to review the literature regarding the NA involvement in PD in order to explore the role of MA. The existing literature about the involvement of the NA in PD was carefully reviewed with emphasis on cellular and molecular changes of this nucleus in PD patients, as well as on psychiatric and motor symptoms of PD related to the NA. Review-based suggestions for possible causes, clinical consequences and other aspects of MA are in turn provided. Discussion The NA is crucially involved in PD, not only in its pathogenesis and clinical manifestations but in the effects of several treatment efforts as well. DAergic degeneration seems to precede clinical phenotype. Some motor and psychiatric symptoms may share a common pathophysiological process mediated by the NA. Neuronal loss due to DAergic degeneration is probably the major cause of MA. Functional NA changes accompany MA. Degeneration of limbic areas is considered as a pathological consequence of MA. Its clinical effects include neuropsychiatric and motor symptoms. MA, as an imaging finding, could be used as a predictive factor for the development of psychiatric manifestations such as depression. MA probably begins in early PD. Conclusion There are important studies confirming the finding of MA in PD and, thanks to several new basic science and clinical data, the clarification of its role has begun. Future studies are expected to improve our understanding of the significance of this phenomenon.