Ea. Macardy et Dc. Riccio, TIME-DEPENDENT CHANGES IN THE EFFECTIVENESS OF A NONCONTINGENT FOOTSHOCK REMINDER, Learning and motivation, 26(1), 1995, pp. 29-42
To investigate the mechanism by which noncontingent reexposure to the
UCS restores an extinguished fear response in rats, a noncontingent fo
otshock reminder was administered to Sprague-Dawley rats at various in
tervals after extinction of a fear response. Reexposure to the UCS res
tored an extinguished fear response if the reminder was administered 7
days after extinction but not immediately or 24 h after extinction. A
second experiment showed that in the 7-day condition prolonged exposu
re to the situational cues following the noncontingent footshock atten
uated recovery of fear. Results are discussed in terms of changes in t
he discriminability of the training and reminder contexts as attribute
s of stimuli are forgotten. (C) Academic Press, Inc.