共查询到20条相似文献，搜索用时 31 毫秒
1.
Three experiments investigated the effects of magnitude and schedule of reinforcement and level of training in instrumental escape learning at a 24-h intertriai interval. In Experiment I, two magnitudes of reinforcement were factorially combined with two schedules of reinforcement (CRF and PRF). Under PRF, large reward produced greater resistance to extinction than did small reward, while the reverse was true under CRF. In Experiment II, two levels of acquisition training were factorially combined with three schedules of reinforcement (CRF, single-alternation, and nonalternated PRF). Patterned running was observed late in acquisition in the single-alternation extended-training condition. Resistance to extinction was greater for the nonalternated PRF condition than for the single-alternation condition following extended acquisition, and the reverse was true following limited acquisition. Experiment III confirmed the extinction findings of Experiment II. The results of all three experiments supported an analysis of escape learning at spaced trials in terms of Capaldi’s (1967) sequential theory. 相似文献
2.
Mark Stanton 《Learning & behavior》1983,11(4):415-423
Sprague-Dawley rat pups aged 14 or 18 days were trained on a patterned (single) alternation schedule with either an 8- or a 105-sec intertriai interval (ITI). At the 8-sec ITI, alternation learning was obtained at both ages, but the older age group learned more rapidly. There was no evidence of response alternation at the 105-sec ITI at either age. Continuously reinforced (CRF) and partially reinforced (PRF) groups trained and extinguished along with the patterned alternation (PA) group at the 105-sec ITI showed a robust partial reinforcement extinction effect (PREE) at both ages. Moreover, there was no difference in the rate of extinction of the PRF and PA groups at either age (i.e., no effect of N-length). A PREE can therefore be obtained in infant rats under conditions that apparently preclude the formation of sequential associations. The implications of this finding for the ontogeny of instrumental learning and extinction are discussed. 相似文献
3.
In the first experiment, a prolonged period of intermittent, unsignaled shocks preceded appetitive runway acquisition, under either continuous (CRF) or partial reinforcement (PRF) and extinction. In the second experiment, the shock treatment came between CRF or PRF acquisition and extinction; and in the third experiment, the shocks intervened between appetitive CRF acquisition and shock-punishment extinction. The main finding was that compared with an unshocked control, shock facilitated acquisition in Experiment 1, and led to increased resistance to extinction and/or punishment in all experiments. In Experiment 1, the shock effect in appetitive extinction was seen mainly in the CRF group; in Experiment 2, the effect was to increase persistence in both the CRF and PRF groups; and in Experiment 3, shock treatment produced stronger resistance to punished extinction. The discussion is in terms of habituation and a general theory of persistence, and the concept of helplessness. 相似文献
4.
Roger L. Mellgren John P. Lombardo Dan M. Wrather Robert Frank Weiss 《Learning & behavior》1973,1(2):105-108
In order to determine the importance of the development of expectancy of reward prior to partial reward trials; rats were given 20 continuously reinforced trials prior to 20 partially reinforced trials (CRF-PRF) and compared to Ss given only 20 partially reinforced trials (PRF). Control groups received 20 or 40 continuously reinforced trials (CRF-20, CRF-40) to determine the effect of differing numbers of acquisition trials. Results showed that terminal acquisition differences were minimal in the run segment of the alley and that Group CRF-PRF was more resistant to extinction than Group PRF, and both were more resistant to extinction than the CRF-20 and CRF-40 groups, which did not differ from each other. These results were interpreted as supporting the notion that the expectancy of reward on nonreward trials during partial reinforcement acquisition is a determiner of the magnitude of the partial reinforcement extinction effect. 相似文献
5.
Stephen C. Brake 《Learning & behavior》1978,6(4):435-443
Rats were given continuous reinforcement (CRF), partial reinforcement (PRF), or successive discrimination (D) training in an alley from 11–14 (Age 1) or 15–18 (Age 2) days of age. Reinforcement was the opportunity to suckle the dry nipples of an anesthetized dam. Following a 10-day interval, all animals were given 4 successive days of discrimination training with food pellets as reinforcement. Control groups were given only the second phase of training. In the first phase, D subjects of both ages responded appropriately to the discriminative stimuli, and the PRF subjects of both ages ran significantly slower than CRF subjects. In the second phase, only the CRF subjects of Age 1 showed behavioral discrimination. All three Age 2 groups discriminated, but the discrimination developed earliest after Phase I CRF and latest after Phase I PRF. Both Age 1 control groups showed a late-developing discrimination, but neither Age 2 control group discriminated. The results suggest that infant and preweanling rats can learn both positive and negative expectancies of appetitive events, respond appropriately, and retain and transfer these expectancies to new learning. The reinforcement value of dry suckling and the effects of stimulus preexposure in infant rats are also discussed. 相似文献
6.
Paul T. P. Wong 《Learning & behavior》1977,5(1):5-13
The behavioral field approach employs naturalistic observation and simultaneous, multiple recordings of ecologically relevant aspects of behavior-environment interactions. Applying this approach to runway learning in the rat, the inferior acquisition speed of partial reinforcement (PRF) subjects as compared to continuous reinforcement (CRF) subjects was found to result from greater response variability, more sniffing and goal-avoidance behavior, and slower dropping out of collateral behaviors (e.g., drinking and sand-digging). Extinction first produced an increase in exploratory behavior, then displacement activities (e.g., grooming and biting) and goal-avoidance. CRF subjects showed greater response persistence as measured by number of extinction trials to disrupt an established, favored path. PRF subjects showed greater goal persistence as measured by trials to retrace from goalbox. In extinction, while CRF subjects were more inclined to engage in drinking and sand-digging in the startbox, PRF subjects exhibited more biting behavior in the goalbox. The only sex-related differences were superior speeds by female CRF subjects, inferior goal speeds by female PRF subjects during acquisition, and superior goalbox escape learning by females in extinction. 相似文献
7.
We examined how a 50% Pavlovian partial reinforcement (PRF) schedule, versus a 100% continuous reinforcement (CRF) schedule,
altered the asymptotic amount and distribution of focal and general search behavior in rats during 48-sec trials with and
without a four-segment interfood clock (S1-S2-S3-S4-US). Under CRF, but not PRF, average asymptotic focal search (nosing in
the feeder) increased across the last two clock segments (S3 and S4), and more for the clock group than the no-clock group.
Locomotor general search peaked in the second clock segment (S2) for the CRF-clock and CRF-no-clock groups and in S3 for the
PRF-clock groups. Furthermore, the ratio of general search to maximum focal search was higher for the PRF-clock group than
for the CRF-clock group. This pattern of results supports the view that predictable reward presentations temporally organize
search states and related responses between food presentations. The relative expression of these responses varies with the
predictability and proximity of reward and is more sharply defined in the presence of a clock. 相似文献
8.
Patricia D. Stokes 《Learning & behavior》1995,23(2):164-176
Potential contributors to sustained levels of variability in the topography of the rat’s barpress were investigated in two experiments. Behavior was classified into discretely defined components, and changes in components and their sequential organization were analyzed. Experiment 1 showed that topographic variability in the rat is modulated by shifts in reinforcement schedules. Variability decreased between either dipper training or extinction and continuous reinforcement (CRF), and increased between CRF and extinction. Once the press was acquired, variability did not change if the schedule (CRF) did not change. Experiment 2 showed that, regardless of subsequent changes in topographic requirements, rats initially shaped to press under more stringent criteria sustained higher levels of variability during CRF, but not during extinction, than rats shaped with less stringent criteria. The results suggest that subjects learn not only what to do during reinforcement but also how differently or variably to do it. 相似文献
9.
Paul T. P. Wong 《Learning & behavior》1978,6(1):82-93
Three runway experiments tested a stage model of extinction which postulated an orderly succession of three qualitatively different stages: habit, trial and error, and resolution. The model predicted that Stage 1 should be characterized by perseveration of habitual routes (i.e., response persistence) and the absence of competing responses; Stage 2, by an increase in investigatory behavior (response variation and hole exploration) and biting behavior; Stage 3, by a decrease in the competing responses of Stage 2 and continued increase in goal avoidance and substitution behavior (e.g., sand-digging). These predictions were largely confirmed. Further, Experiments 1 and 2 showed that, as expected by the model, continuous reinforcement (CRF) resulted in more practice of habitual routes in acquisition and greater response persistence, while partial reinforcement (PRF) resulted in more route variation and hole exploration in acquisition and greater goal persistence which was attributable to prior reinforcement of a trial-and-error coping strategy. Results of Experiment 3, which combined training trials and reward magnitudes orthogonally, supported the prediction that response persistence was positively related to training trials, and goal persistence negatively related to reward magnitudes. All three experiments demonstrated an inverted-U function in investigatory and biting behavior, as predicted by the stage model. 相似文献
10.
Masato Ishida 《Learning & behavior》1986,14(3):293-300
When extinction is delayed very long, the superior resistance to extinction of the random schedule group relative to the alternating schedule group disappears (partial reinforcement delayed extinction effect, PRDE). Two experiments assessed the effects of reinforcement/nonreinforcement on Trial 1 on the PRDE. Following extended partial reinforcement acquisition training in a runway, rats received extinction training after a short (1-day) or long (23-day) retention interval. The schedules used in Experiment 1 were: a single-alternation (SA) schedule beginning each day with a rewarded (r) trial, for Group r-SA; an SA schedule beginning with a nonrewarded (n) trial, for Group n-SA; and a random (Rd) schedule, for Group Rd. The schedules and group names used in Experiment 2 were r-SA, Rd, and r-Rd. The results were that (1) rats given r-SA schedules yielded considerable resistance under delayed extinction, (2) those given Rd and r-Rd schedules showed a decline in resistance to extinction over a long retention interval, (3) those given the n-SA schedule showed relatively low resistance at both retention intervals, although retention deficit was not greater than in the case of the Rd schedule, and thus, (4) the PRDE was found in both experiments, although only weakly in Experiment 1. The results indicated that a regularly alternating reward pattern was a more important determinant than was type of reward on Trial 1 for the PRDE. The PRDE due to differential retention deficits among schedules is discussed on the basis of dual-process associative sequential mechanisms and cognitive rule-encoding mechanisms. 相似文献
11.
Four groups of 10 rats each were given six acquisition trials (Phase 1) under continuous reinforcement (CR), partial reinforcement (PR), constant delay (CD), or partial delay of reinforcement (PD) conditions. In Phase 2, all Ss were given 18 nonreinforced trials, followed by 12 continuously reinforced trials in Phase 3. In Phase 4, all Ss were given 12 more extinction trials. A constant 24-h ITI was observed throughout the experiment. A strong partial reinforcement extinction effect (PREE) was obtained in both Phases 2 and 4. Only a temporary partial delay of reinforcement effect (PDRE) was observed, which was restricted to the first nine trials of the first extinction phase. No constant delay of reinforcement effect (CDRE) was observed in either extinction phase. The results were discussed in terms of both frustration and sequential theories. 相似文献
12.
Steven J. Haggbloom 《Learning & behavior》1980,8(3):441-446
The effects of transitions from nonrewarded (N) to rewarded (R) trials (N-R transitions) on discriminative behavior in differential conditioning and subsequent resistance to extinction were investigated in two experiments. In Experiment 1, groups given N-R transitions within S+ were more resistant to discrimination (ran fast in S?) and extinction than were groups given a partial reinforcement (PRF) schedule in S+ devoid of N-R transitions. Experiment 2 indicated that N-R transitions that occur when an N trial in S? is followed by an R trial in S+ are as effective in increasing resistance to discrimination, but not resistance to extinction, as are N-R transitions that occur within S+. The sequential effects obtained here were highly similar to those in conventional PRF and support the view that differential conditioning and PRF are highly interrelated phenomena. The results are discussed in terms of the extension of sequential theory to differential conditioning and the importance of internal reward-produced cues in discrimination learning. 相似文献
13.
Steven J. Haggbloom 《Learning & behavior》1980,8(3):424-428
In two differential conditioning experiments, groups of 10 rats each differed with respect to average reward and schedule of reward received in S+. Nonreward (N) occurred on all S? trials. In both experiments, extinction of responding to S? (resistance to discrimination) was extensively regulated by reward sequence and was largely independent of average reward. In Experiment 1, resistance to discrimination was a function of transitions from N to rewarded (R) trials (N-R transitions). In Experiment 2, resistance to discrimination was increased by large reward on the R trial of N-R transitions and decreased by large reward on the R trial of R-N transitions. These schedule effects on resistance to discrimination parallel the effects of comparable schedules on resistance to extinction following partial reinforcement. The results are discussed in terms of sequential theory, reinforcement level theory, and their implications for various schedule manipulations that have previously shown S? behavior to be inversely related to average reward in S+. 相似文献
14.
In two experiments, two groups of rats were trained in a navigation task according to either a continuous or a partial schedule
of reinforcement. In Experiment 1, animals that were given continuous reinforcement extinguished the spatial response of approaching
the goal location more readily than animals given partial reinforcement—a partial reinforcement extinction effect. In Experiment
2, after partially or continuously reinforced training, animals were trained in a new task that made use of the same reinforcer
according to a continuous reinforcement schedule. Animals initially given partial reinforcement performed better in the novel
task than did rats initially given continuous reinforcement. These results replicate, in the spatial domain, well-known partial
reinforcement phenomena typically observed in the context of Pavlovian and instrumental conditioning, suggesting that similar
principles govern spatial and associative learning. The results reported support the notion that salience modulation processes
play a key role in determining partial reinforcement effects. 相似文献
15.
In two experiments, the hypothesis that frustration mediates the production of schedule-induced polydipsia was tested. In Experiment I, a group in which reward was reduced from 6 to 2 pellets of food in an operant chamber was found to increase water intake compared to a group maintained at 2 pellets reward. In Experiment II, rats trained to approach food on a partial reinforcement schedule in a runway subsequently showed lower levels of water intake in the operant test for polydipsia than rats given continuous reinforcement during runway training. The results are interpreted as supporting a frustration hypothesis of schedule-induced polydipsia and are discussed within the context of persistence theory. 相似文献
16.
Charles I. Brooks 《Learning & behavior》1975,3(1):67-72
In Experiment I, rats which had received six partially reinforced runway acquisition trials, with a reward magnitude of 60 sec access to wet mash on rewarded trials, showed less persistent responding over highly massed extinction trials than subjects which had received the same acquisition schedule but reward magnitudes of either 1 or 10 45-mg pellets. In Experiment II, rats which had received six partially reinforced placements into one compartment of a two-compartment box, with 60 sec access to mash on rewarded placements, jumped a hurdle faster to escape nonreward than subjects which had received the same reward schedule but 10 45-mg pellets on rewarded trials. The data supported a primary frustration analysis for reward-magnitude manipulations within brief partial-reinforcement schedules. 相似文献
17.
Rats were trained on a daily partial reward schedule of small magnitude of reward (S), nonreward (N), and large magnitude of reward (L), which began with SN or SSNN for all animals. The remainder of the daily schedule was defined by the factorial combination of the number of rewards (1 vs. 3) and the magnitude of reward (S vs. L). Following 18 days of such training, 20 trials of extinction were administered. It was found that increasing the number of rewarded trials in a partial reinforcement schedule decreased resistance to extinction. Furthermore, increased number of large-magnitude rewards reduced resistance to extinction to a greater extent than increased number of small-magnitude rewards. 相似文献
18.
Two experiments were conducted to assess the effects of the introduction of schedules of partial reinforcement (PRF), subsequent to continuous reinforcement training, on the maintenance and resistance to extinction of the rabbit’s nictitating membrane CR. Substantial response levels were maintained by schedules of reinforcement as lean as 15%, and the performance decrements, when observed to be reliable, could not be localized to the immediate effects of one, two, or three consecutive nonreinforced trials by the examination of conditional response probabilities. Moreover, reliable PRF extinction effects were obtained. The relevance of these findings to the purported empirical divergence of PRF effects on classical and instrumental conditioning were discussed. 相似文献
19.
Dorothy E. McAllister Wallace R. McAllister Stephen E. Dieter 《Learning & behavior》1976,4(2):204-209
In Experiment I, eight groups of rats (n = 20) were given shuttlebox-avoidance training. Two levels of shock (.3 and 1.6 mA) were combined factorially with two levels of reward (large and small) under both continuous and discontinuous (.75 sec on and 2.00 sec off) shock. Visual situational cues were absent after a shuttle response for the large-reward condition and present for the small-reward condition. Superior performance was obtained with weak rather than strong shock under both reward conditions and with large rather than small reward only under the weak-shock condition. Continuity of shock had no differential effect on performance. Experiment II allowed the conclusion that the reward effect was attributable to a reinforcement mechanism. The data were taken as support for the effective reinforcement theory, which emphasizes the importance in avoidance learning of fear conditioned to situational cues. 相似文献
20.
Charles I. Brooks 《Learning & behavior》1980,8(1):143-151
Four experiments compared runway extinction or hurdle-jumping from nonreward performance following brief (10 trials) continuous or partial reinforcement acquisition. Some of the partial groups received all nonrewarded trials prior to any rewards. The major findings were that (l) rats receiving all nonrewarded experiences prior to rewarded ones were more persistent during extinction than continuously rewarded subjects; (2) rats receiving nonrewarded placements prior to rewarded ones in one compartment of a two-compartment box, failed to learn a hurdle-jumping response to escape nonreward, whereas rats not receiving the initial nonrewards did learn the escape response; (3) increasing the number of rewarded placements following initial nonrewarded ones offset the effect noted in (2). The results, which are discussed in the context of a frustration analysis of the small-trials partial reinforcement effect, suggest that incentive growth over rewarded trials is retarded when the rewards have been preceded by nonrewards. The similarity of these results to those investigating the phenomenon of latent inhibition is apparent, and possible mechanisms responsible for the present results are suggested in current theoretical accounts of latent inhibition. 相似文献