Effect of N-R transitions during partial reinforcement pretraining on subsequent resistance to discrimination

Abstract

Three groups of 12 rats received 25 pretraining trials to each future discriminandum employed in a subsequent differential brightness conditioning problem. Groups NR and RN received partial reinforcement (PRF) pretraining either with or without, respectively, transitions from nonrewarded to rewarded trials (N-R transitions). Group CRF received consistent reinforcement during pretraining. A fourth group (n=12), Group NP, received no pretraining. During discrimination learning, one-half of the rats in each group received all their daily S+ trials preceding their daily S-trials (+-sequence); the remainder of the rats received an intermixed sequence of trials to S+ and S-(+-+ sequence). Discrimination learning was faster under the +-sequence than under the +-+ condition, and discrimination learning was retarded in Group NR relative to the other three groups, which did not differ from one another, under both the +-and +-+ discrimination sequence conditions. The results are discussed with reference to previous experiments demonstrating N-R transition effects on discrimination learning, a theoretical extension of sequential theory to discrimination learning, and the effects of nondifferential reinforcement prior to discrimination learning on learned irrelevance.Discrimination learning is retarded in groups given an intermixed sequence of trials to the positive (S+ ) and negative (S-) stimuli, which contains transitions from nonrewarded trials in S-to rewarded trials in S+ (N-R transitions), relative to groups given all of their daily S+ trials preceding their daily S-trials (Haggbloom, 1978;Haggbloom & Tillman, 1980). Partial reinforcement (PRF) administered within S+ also retards discrimination learning, but only if the S+ PRF schedule containsN-Rtransitions (Haggbloom, 1980a(Haggbloom, , 1980b(Haggbloom, , 1980c(Haggbloom, , 1981b McHose & Blackwell, (197S). These effects of N-R transitions on discrimination learning are due primarily to retarded extinction of responding to S-, a behavior termed resistance to discrimination (Haggbloom, 1980b).The effect of N-R transitions on resistance to discrimination parallels the effect of that variable on resistance to extinction following conventional PRF (e.g., Capaldi, 1966). And both effects appear to be due to the behavioral control acquired by SN, the memory of nonreward. In discrimination learning, SN enters into a stimulus compound with the nominally relevant discriminanda (e.g., brightness cues) and can control behavior in a way that either interferes with or complements the control exercised by

Serial learning, interitem associations, phrasing cues, interference, overshadowing, chunking, memory, and extinction

“…The shift to an extinction series employed here, however, has a marked advantage: N-R transitions have been examined in a wide variety of more orthodox instrumental learning situations and with effects similar to those obtained here. Thus, N-R transitions have been shown to reduce discriminative responding (e.g., Capaldi et al, 1975;Capaldi et al, 1984;Haggbloom, 1980bHaggbloom, , 1982, to retard reversal learning in discrimination tasks (e.g., Grosslight & Radlow, 1956;Haggbloom & Tillman, 1980), to reduce the simultaneous and successive negative contrast effects (Campbell & Meyer, 1971;Capaldi & Ziff, 1969), and to elevate resistance to extinction: in punishment situations (Capaldi & Levy, 1972), in escape situations (Seybert, lobe, & Eckert, 1974), in the S+ alternative of discrimination tasks (e.g., Capaldi et aI., 1975;Haggbloom, 1980b), and in reward schedule situations in animals (e.g., Capaldi, 1964Capaldi, , 1967Leonard, 1969) and people (e.g., Grosslight, Hall, & Murin, 1953). Similarities of the sort noted above support the view that serial learning, whatever its unique characteristics, may be viewed as continuous with various more orthodox instrumental learning situations.…”

The sequential view: From rapidly fading stimulus traces to the organization of memory and the abstract concept of number

“…Those that occur within the same alternative are effective in the sense that SN stored on one trial is retrieved on the next trial, both early in training and late in training (e.g., Haggbloom, 1980aHaggbloom, , 1982: However, those that occur from S-to S+ appear to be effective in the sense described above only in the early trials of discrimination training (see especially Haggbloom, 1980a;Capaldi et al, 1991). In short, it appears that in the early trials of discrimination training, a memory stored in a given alternative will be retrieved on a subsequent trial in the other alternative.…”

“…In those investigations, groups that have received NR transitions within S+ have shown greater resistance to extinction and to discrimination and poorer reversallearning than groups that have not received such transitions (Haggbloom, 1980a(Haggbloom, , 1982.…”

Alley section effects on blocking

“…Hedonic memories, the internal cues produced by such events as food reward, nonreward, and shock, have been shown to powerfully control responding in a wide variety of instrumental learning situations (see, e.g., Capaldi, 1966Capaldi, ,1967Capaldi & Verry, 1981 ;Haggbloom, 1982;Seybert, Mellgren, lobe, & Eckert, 1974). Indeed, the powerful control exercised by hedonic memories in instrumental as opposed to classical tasks may be one of the major differences between the two situations (see , e.g., Neely & Wagner, 1974).…”