CALCA and Anorexia: Calca‐expressing PB neurons form a critical link in signaling pathways for conditioned taste aversion, malaise, and anorexia, plus alerting responses to aversive stimuli that include pain, itch, and hypercarbia (Carter et al., 2015; Chen et al., 2018; Kaur et al., 2017; Palmiter, 2018; Saper, 2016).