title: An animal model of disengagement: Temporary inactivation of the superior colliculus impairs attention disengagement in rats.
abstract: The orienting attention network is responsible for prioritizing sensory input through overt or covert shifts of attention among targets. The ability to disengage attention is essential for the proper functioning of this network. In addition to its importance for proper orienting, deficits in disengagement have been recently implicated in autism disorders. Despite its importance, the neural mechanisms underlying disengagement processing are still poorly understood. In this study, the involvement of the superior colliculus (SC) in disengagement was investigated in unrestrained rats that had been trained in a two-alternative light-guided spatial choice task. At each trial, the rats had to choose one of two paths, leading either to a large or a small reward, based on 1 (single-cue) or 2 (double-cue) lights. The task consisted of serial trials with single- and/or double-cue lights, and rats could acquire a large reward if the rats chose infrequent lights when infrequent cue lights were presented after preceding frequent cue lights. Experiment 1 included trials with either single- or double-cue lights, and infrequent trials with double-cue lights required both attentional disengagement and shift of attention from preceding frequent single-cue lights, while experiment 2 included only trials with single-cue lights requiring shifts of attention but not attentional disengagement. The results indicated that temporary inactivation of the SC by muscimol injections selectively impaired performance on trials requiring disengagement. No impairment was observed on the other trials, in which attention disengagement was not required. The results provide the first evidence that the SC is necessary for attentional disengagement.
authors.affiliation: System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, 2630, Toyama 930-0194, Japan; Edmond and Lily Safra International Institute of Neuroscience, Santos Dumont Institute, Rodovia RN 160, 3001 - Distrito Jundiaí, 59280-000 Macaíba, RN, Brazil.
authors.forename: Mariana Ferreira Pereira
authors.initials: MF
authors.lastname: de Araujo
authors.affiliation: System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, 2630, Toyama 930-0194, Japan.
authors.forename: Jumpei
authors.initials: J
authors.lastname: Matsumoto
authors.affiliation: System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, 2630, Toyama 930-0194, Japan.
authors.forename: Taketoshi
authors.initials: T
authors.lastname: Ono
authors.affiliation: System Emotional Science, Graduate School of Medicine and Pharmaceutical Sciences, University of Toyama, Sugitani, 2630, Toyama 930-0194, Japan. Electronic address: nishijo@med.u-toyama.ac.jp.
authors.forename: Hisao
authors.initials: H
authors.lastname: Nishijo
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D001288:Attention / Q000187:drug effects; D001289:Attention Deficit Disorder with Hyperactivity / Q000139:chemically induced / Q000209:etiology*; D003216:Conditioning, Operant / Q000187:drug effects / Q000502:physiology; D003463:Cues; D004195:Disease Models, Animal; D007839:Functional Laterality / Q000187:drug effects; D058785:GABA-A Receptor Agonists / Q000494:pharmacology; D008297:Male; D009118:Muscimol / Q000494:pharmacology; D009949:Orientation / Q000187:drug effects; D051381:Rats; D017208:Rats, Wistar; D011930:Reaction Time / Q000187:drug effects; D013477:Superior Colliculi / Q000187:drug effects / Q000502:physiology*
chemical_list: D058785:GABA-A Receptor Agonists; D009118:Muscimol
keywords: Attention; Autism; Disengagement; Orienting network; Superior colliculus; Temporary inactivation