On the Transition from Reconsolidation to Extinction of Contextual Fear Memories

Autor/inn/en	Cassini, Lindsey F.; Flavell, Charlotte R.; Amaral, Olavo B.; Lee, Jonathan L. C.
Titel	On the Transition from Reconsolidation to Extinction of Contextual Fear Memories
Quelle	In: Learning & Memory, 24 (2017) 9, S.392-399 (8 Seiten) PDF als Volltext Verfügbarkeit
Sprache	englisch
Dokumenttyp	gedruckt; online; Zeitschriftenaufsatz
ISSN	1072-0502
DOI	10.1101/lm.045724.117
Schlagwörter	Fear; Memory; Learning Processes; Recall (Psychology); Cues; Context Effect; Experiments; Animals; Conditioning; Genetics; Statistical Analysis + Suchen Sie Ihr Suchwort? Furcht; Gedächtnis; Learning process; Lernprozess; Abberufung; Stichwort; Erprobung; Animal; Tier; Tiere; Humangenetik; Statistische Analyse
Abstract	Retrieval of an associative memory can lead to different phenomena. Brief reexposure sessions tend to trigger reconsolidation, whereas more extended ones trigger extinction. In appetitive and fear cued Pavlovian memories, an intermediate "null point" period has been observed where neither process seems to be engaged. Here we investigated whether this phenomenon extends to contextual fear memory. Adult rats were subjected to a contextual fear conditioning paradigm, reexposed to the context 2 d later for 3, 5, 10, 20, or 30 min, with immediate injections of MK-801 or saline following reexposure, and tested on the following day. We observed a significant effect of MK-801 with the 3- and 30-min sessions, impairing reconsolidation and extinction, respectively. However, it did not have significant effects with 5-, 10-, or 20-min sessions, even though freezing decreased from reexposure to test. Further analyses indicated that this is not likely to be due to a variable transition point at the population level. In conclusion, the results show that in contextual fear memories there is a genuine "null point" between the parameters that induce reconsolidation and extinction, as defined by the effects of MK-801, although NMDA receptor-independent decreases in freezing can still occur in these conditions. (As Provided).
Anmerkungen	Cold Spring Harbor Laboratory Press. 500 Sunnyside Boulevard, Woodbury, NY 11797-2924. Tel: 800-843-4388; Tel: 516-367-8800; Fax: 516-422-4097; e-mail: cshpres@cshl.edu; Web site: http://learnmem.cshlp.org
Erfasst von	ERIC (Education Resources Information Center), Washington, DC
Update	2020/1/01