Dopaminoceptive Forebrain Regions: A Search for Structural and Functional Organization Underlying Normal and Impaired Social Adaptation.

Of the multifaceted brain systems engaging dopaminergic neurotransmission, a prominent role is attributed to the ascending dopaminergic pathways arising from several source nuclei and areas of the brainstem, and profusely innervating cortical and subcortical regions of the forebrain. Monoamines, including dopamine, are simple molecules with well-known synthetic and degradation mechanisms, and an excessive range of bioactive targets and effects, some also susceptible to pharmacological intervention. Based upon a vast literature on dopamine receptors and signaling pathways, dopamine has been implicated in many different regulatory systems, such as locomotor organization (action selection) via the nigrostriatal pathway, reward and motivation via the mesolimbic pathway, or cognitive flexibility and associative learning via the mesolimbic and mesocortical systems (including pathways to ventral striatum and amygdala, which are relevant to select the adequate action in order to maximize reward or avoid punishment in response to unpredictable stimuli). It appears that dopamine is a versatile molecular currency, accepted by a multitude of neural systems, a genuine ‘open sesame’ to key mechanisms. However, its final action depends on the proximity of targets, distribution, and availability of receptors and, most importantly, on the neuroanatomical organization of dopamine-recipient brain regions.

It is this latter aspect that the current Research Topic is specifically aimed at. Thanks to long-going investigations in the field, an impressive body of knowledge has been gathered regarding the importance of dopaminoceptive regions and dopaminergic mechanisms in human diseases and disorders. Prominent examples are Parkinsonism and other locomotor disorders, motivational and emotional disturbances from anxiety to depression. In addition, increasing significance is being attributed to dopaminergic dysregulation in social maladaptation conditions, going as far as the formulation of a ‘dopamine theory’ of Autism (ASD).

With many potential ramifications and translational aspects, we expect to attract considerable interest with this effort. Not excluding other approaches, the Editors are inviting contributions mainly from the field of experimental neuroscience, with a distinct structural and functional relevance for the composition and potential disturbances of dopaminergic pathways innervating various forebrain targets. Preference will be given to studies with an emphasis on neuroanatomy, however, other contributions based upon comparative, developmental or neurochemical or functional aspects are also welcome. Human clinical observations might also be included, if directly relevant to (or presented in parallel with) experimental studies, e.g. animal models for human diseases. In addition to research reports, reviews and opinion papers can also be considered. Nevertheless, the Editors would not encourage submission of purely behavioral studies without reference to underlying brain mechanisms (functional or structural).