title: Reappraising striatal D1- and D2-neurons in reward and aversion.
abstract: The striatum has been involved in complex behaviors such as motor control, learning, decision-making, reward and aversion. The striatum is mainly composed of medium spiny neurons (MSNs), typically divided into those expressing dopamine receptor D1, forming the so-called direct pathway, and those expressing D2 receptor (indirect pathway). For decades it has been proposed that these two populations exhibit opposing control over motor output, and recently, the same dichotomy has been proposed for valenced behaviors. Whereas D1-MSNs mediate reinforcement and reward, D2-MSNs have been associated with punishment and aversion. In this review we will discuss pharmacological, genetic and optogenetic studies that indicate that there is still controversy to what concerns the role of striatal D1- and D2-MSNs in this type of behaviors, highlighting the need to reconsider the early view that they mediate solely opposing aspects of valenced behaviour.
authors.affiliation: Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga, Guimarães, Portugal.
authors.forename: Carina
authors.initials: C
authors.lastname: Soares-Cunha
authors.affiliation: Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga, Guimarães, Portugal.
authors.forename: Barbara
authors.initials: B
authors.lastname: Coimbra
authors.affiliation: Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga, Guimarães, Portugal.
authors.forename: Nuno
authors.initials: N
authors.lastname: Sousa
authors.affiliation: Life and Health Sciences Research Institute (ICVS), School of Health Sciences, University of Minho, Braga, Portugal; ICVS/3B's-PT Government Associate Laboratory, Braga, Guimarães, Portugal. Electronic address: ajrodrigues@ecsaude.uminho.pt.
authors.forename: Ana J
authors.initials: AJ
authors.lastname: Rodrigues
mesh_terms: D003342:Corpus Striatum; D009474:Neurons; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2; D012201:Reward
chemical_list: D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2
keywords: Aversion; D1 dopamine receptor; D2 dopamine receptor; Dopamine; Dorsal striatum; Medium spiny neurons; Mesolimbic; Nigrostriatal; Nucleus accumbens; Reinforcement; Reward