Stimulus Control of Delayed Matching in Pigeons: Directed Forgetting

Abstract

Pigeons were trained in delayed matching-to-sample with two postsample stimuli. A postsample R-cue signaled that a matching choice phase would follow. A postsample F-cue signaled that a matching choice phase would not follow. Previous research found reduced matching accuracy on F-cued probe trials when comparison stimuli were presented in the choice phase. The present four experiments systematically varied the events following an F-cue to determine the conditions under which the F-cue reduces delayed-matching accuracy. When F-cues and R-cues controlled different behavior, matching on probe trials was poor. When both cues controlled the same behavior, matching on probe trials was good. This result is best explained by the theory that comparison stimuli retrieve the sample representation, but only in the behavioral context established by the R-cue. The present research supports the view that response-produced stimuli serve a contextual role in animal short-term memory.

The role of interpolated stimuli in the retroactive interference of pigeon short-term memory

“…What role in short-term memory can be served by such delay behavior? Kendrick et al (1981) proposed that response-produced stimuli arising from delay behavior serve as a context supporting retrieval of sample stimulus information. We proposed that delay behavior is the context in which sample information is maintained via cover rehearsal.…”

“…(Bouton & Bolles, 1979;Olton, 1978;Tomie, 1976;Wagner, 1978). Recent investigations of human and animal short-term memory have indicated contextdependent retrieval in directed forgetting (Bjork & Geiselman, 1978;Kendrick et al, 1981;Stonebraker et al, 1981). Furthermore, a two-stores account of human memory with two operating processes, one for long-term memories and one for short-term memories, is no longer seriously accepted (Anderson, 1982;Lewis, 1979;Murdock 1982;Raaijmakers & Shiffrin, 1981).…”

“…Alternatively, Kendrick et al (1981) argued that baseline delay behavior generated response-produced stimuli that served as the context in which test stimuli effect retrieval of sample representations. This retrieval position does not necessarily deny rehearsal in animals, but proposes a secondary mechanism that operates when sample information has not been rehearsed.…”

Differential outcome expectancies and directed forgetting effects in pigeons

“…For example, following a vertical line, comparison stimuli may always be omitted (i.e., a forget, or "F" cue), whereas following a horizontal line, comparison stimuli are always presented (i.e., a remember, or "R," cue). By employing a probe-testing procedure in which comparison stimuli are infrequently presented after F cues, it has been shown that F cues control a lower level of matching accuracy than do R cues, which signal presentation of the comparisons (Grant,1981;Kendrick, Rilling, & Stonebraker, 1981;Maki & Hegvik, 1980;Maki, Olson, & Rego, 1981;Santi & Savich, 1985). The magnitude of the performance decrement produced by F cues has been shown to be greater as the retention interval is lengthened (Grant, 1981;Maki & Hegvik, 1980).…”

“…Furthermore, if the occurrence of the F cue is delayed within the retention interval, the effectiveness of the cue is reduced (Grant, 1981;Stonebraker & Rilling, 1981). Experiments utilizing two cues have shown that the presentation of an R cue immediately after an F cue mitigates the decrement in matching accuracy produced by the F cue (Grant, 1981;Stonebraker, Rilling, & Kendrick, 1981).…”