title: Motivational activation: a unifying hypothesis of orexin/hypocretin function.
abstract: Orexins (hypocretins) are two peptides (orexin A and B) produced from the pre-pro-orexin precursor and expressed in a limited region of dorsolateral hypothalamus. Orexins were originally thought to specifically mediate feeding and promote wakefulness, but it is now clear that they participate in a wide range of behavioral and physiological processes under select circumstances. Orexins primarily mediate behavior under situations of high motivational relevance, such as during physiological need states, exposure to threats or reward opportunities. We hypothesize that many behavioral functions of orexins (including regulation of sleep/wake cycling) reflect a fundamentally integrated function for orexins in translating motivational activation into organized suites of psychological and physiological processes supporting adaptive behaviors. We also discuss how numerous forms of neural heterogeneity modulate this function, allowing orexin neurons to organize diverse, adaptive responses in a variety of motivationally relevant situations. Thus, the involvement of orexins in diverse behaviors may reflect a common underlying function for this peptide system.
authors.affiliation: Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina, USA.
authors.forename: Stephen V
authors.initials: SV
authors.lastname: Mahler
authors.affiliation: 1] Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina, USA. [2] Department of Psychological and Brain Sciences, University of Massachusetts Amherst, Amherst, Massachusetts, USA.
authors.forename: David E
authors.initials: DE
authors.lastname: Moorman
authors.affiliation: Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina, USA.
authors.forename: Rachel J
authors.initials: RJ
authors.lastname: Smith
authors.affiliation: Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina, USA.
authors.forename: Morgan H
authors.initials: MH
authors.lastname: James
authors.affiliation: Department of Neuroscience, Medical University of South Carolina, Charleston, South Carolina, USA.
authors.forename: Gary
authors.initials: G
authors.lastname: Aston-Jones
mesh_terms: D000818:Animals; D005247:Feeding Behavior / Q000502:physiology; D006801:Humans; D047908:Intracellular Signaling Peptides and Proteins / Q000502:physiology*; D008954:Models, Biological; D009042:Motivation / Q000502:physiology*; D009479:Neuropeptides / Q000502:physiology*; D000068797:Orexins; D014851:Wakefulness / Q000502:physiology
chemical_list: C000596229:HCRT protein, human; D047908:Intracellular Signaling Peptides and Proteins; D009479:Neuropeptides; D000068797:Orexins