A small region on either side of the pons containing neurons that secrete noradrenalin (norepinephrine) and serotonin, prominently implicated in anxiety and fear, and responsible for initiating REM sleep after a period of slow-wave sleep. Also spelt locus ceruleus. See also subcoerulear nucleus. [From Latin locus a place + caelum sky, referring to its deeply pigmented appearance]
Subjects: Medicine and Health — Psychology.