“…AAC renewal is the recovery of an extinguished CR when acquisition and extinction occur in the same context but testing occurs in a different, neutral one (e.g., Bouton & Ricker, 1994). Most evidence suggests that ABA and ABC renewal are stronger than AAC renewal, which sometimes is not even observed (Crombag & Shaham, 2002;Cuevas, Rovee-Collier, & Learmonth, 2008;Nakajima, Tanaka, Urushihara, & Imada, 2000;Rescorla, 2008;Tamai & Nakajima, 2000;Tamai, Nakajima, Kitaguchi, & Imada, 2001; Thomas, Larsen, & Ayres, 2003;Üngör & Lachnit, 2008;Yap & Richardson, 2007). But in our opinion, why AAC renewal is weaker than ABA and ABC renewal has not yet been adequately explained.…”