title: Prediction error and trace dominance determine the fate of fear memories after post-training manipulations.
abstract: Different mnemonic outcomes have been observed when associative memories are reactivated by CS exposure and followed by amnestics. These outcomes include mere retrieval, destabilization-reconsolidation, a transitional period (which is insensitive to amnestics), and extinction learning. However, little is known about the interaction between initial learning conditions and these outcomes during a reinforced or nonreinforced reactivation. Here we systematically combined temporally specific memories with different reactivation parameters to observe whether these four outcomes are determined by the conditions established during training. First, we validated two training regimens with different temporal expectations about US arrival. Then, using Midazolam (MDZ) as an amnestic agent, fear memories in both learning conditions were submitted to retraining either under identical or different parameters to the original training. Destabilization (i.e., susceptibly to MDZ) occurred when reactivation was reinforced, provided the occurrence of a temporal prediction error about US arrival. In subsequent experiments, both treatments were systematically reactivated by nonreinforced context exposure of different lengths, which allowed to explore the interaction between training and reactivation lengths. These results suggest that temporal prediction error and trace dominance determine the extent to which reactivation produces the different outcomes.
authors.affiliation: Laboratorio de Psicología Experimental, Facultad de Psicología.
authors.forename: Joaquín M
authors.initials: JM
authors.lastname: Alfei
authors.affiliation: Laboratorio de Psicología Experimental, Facultad de Psicología.
authors.forename: Roque I
authors.initials: RI
authors.lastname: Ferrer Monti
authors.affiliation: Departamento de Farmacología, Facultad de Ciencias Químicas, Universidad Nacional de Córdoba, Córdoba, 5000, Argentina.
authors.forename: Victor A
authors.initials: VA
authors.lastname: Molina
authors.affiliation: Laboratorio de Psicología Experimental, Facultad de Psicología.
authors.forename: Adrián M
authors.initials: AM
authors.lastname: Bueno
authors.affiliation: Department of Psychology and Behavioural and Clinical Neuroscience Institute, University of Cambridge, Cambridge CB2 3EB, United Kingdom gonurcelay@gmail.com.
authors.forename: Gonzalo P
authors.initials: GP
authors.lastname: Urcelay
mesh_terms: D000818:Animals; D003213:Conditioning, Psychological / Q000187:drug effects / Q000502:physiology; D004597:Electroshock; D005239:Fear / Q000187:drug effects / Q000502:physiology*; D046352:Freezing Reaction, Cataleptic / Q000187:drug effects / Q000502:physiology; D008297:Male; D008568:Memory / Q000187:drug effects / Q000502:physiology*; D008874:Midazolam / Q000494:pharmacology; D009483:Neuropsychological Tests; D011619:Psychotropic Drugs / Q000494:pharmacology; D011897:Random Allocation; D017208:Rats, Wistar; D012054:Reinforcement, Psychology; D013997:Time Factors
chemical_list: D011619:Psychotropic Drugs; D008874:Midazolam