“…Here, stimuli (conditioned stimuli, CSs) that are associated with primary rewards (unconditioned stimuli, USs) acquire the ability to produce effects similar to the US including the capacity to elicit conditioned approach responses and to function as conditioned rewards in their own right (Beninger and Ranaldi, 1992; Skinner, 1938). We have proposed and demonstrated through a series of studies that the acquisition by a CS of the capacity to function as such depends on its acquired capacity to activate the same neural system—ventral tegmental area (VTA) dopamine (DA) neurons—that are unconditionally activated by the primary reward (Galaj et al, 2017; Galaj and Ranaldi, 2018; Kest et al, 2012; Ranaldi, 2014; Ranaldi et al, 2011; Zellner et al, 2009; Zellner and Ranaldi, 2010). Pedunculopontine tegmental, basolateral amygdala, and prefrontal cortical afferents to the VTA DA system, a system that plays a critical role in conditioned reward learning (Burns et al, 1993; Everitt and Robbins, 1992; Pears et al, 2003; Ranaldi, 2014), are severely impacted by CIE exposure (Arendt et al, 1988; Broadwater et al, 2018; Coleman et al, 2014; Jury et al, 2017; McGinnis et al, 2019; Morales et al, 2018; Pereira et al, 2019; Schindler et al, 2016; Vetreno et al, 2014).…”