Open AccessNoradrenaline Improves Behavioral Contrast Sensitivity via the β-Adrenergic Receptor
Author(s) -
Ryo Mizuyama,
Shogo Soma,
Naofumi Suemastu,
Satoshi Shimegi
Publication year - 2016
Publication title -
plos one
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.99
H-Index - 332
ISSN - 1932-6203
DOI - 10.1371/journal.pone.0168455
Subject(s) - idazoxan , prazosin , locus coeruleus , stimulus (psychology) , receptor , neuroscience , adrenergic receptor , endocrinology , medicine , yohimbine , propranolol , chemistry , biology , psychology , antagonist , central nervous system , cognitive psychology
Noradrenaline (NA) is released from the locus coeruleus in the brainstem to almost the whole brain depending on the physiological state or behavioral context. NA modulates various brain functions including vision, but many questions about the functional role of its effects and mechanisms remain unclear. To explore these matters, we focused on three questions, 1) whether NA improves detectability of a behavior-relevant visual stimulus, 2) which receptor subtypes contribute to the NA effects, and 3) whether the NA effects are specific for visual features such as spatial frequency (SF). We measured contrast sensitivity in rats by a two-alternative forced choice visual detection task and tested the effects of NA receptor blockers in three SF conditions. Propranolol, a β-adrenergic receptor inhibitor, significantly decreased contrast sensitivity, but neither prazosin nor idazoxan, α 1- and α 2- adrenergic receptor inhibitors, respectively, had an effect. This β blocker effect was observed only at optimal SF. These results indicate that endogenous NA enhances visual detectability depending on stimulus spatial properties via mainly β-adrenergic receptors.