共查询到20条相似文献，搜索用时 31 毫秒
1.
Charles F. Levinthal Ross H. Tartell Carrie M. Margolin Howard Fishman 《Learning & behavior》1985,13(3):228-232
In Experiment 1, four values of conditioned stimulus-unconditioned stimulus interval, or interstimulus interval (ISI) (200, 500, 800, and 1,100 msec) were studied in one trial/day acquisition of the conditioned nictitating membrane response of the rabbit. The 1,100-msec ISI group was superior to the other groups, contrary to the usual findings of ISI studies in the conditioning literature. In Experiment 2, effective conditioning levels were attained with an ISI as long as 2,200 msec, when the intertriai interval was set at either 24 or 48 h. Results are interpreted in terms of the role of orienting responses in the conditioning process. 相似文献
2.
Conditioned lick suppression in rats was used to explore the role of timing in trace conditioning. In Experiment 1, two groups of rats were exposed to pairings of a CS (CS1) with a US, under conditions in which the interstimulus interval (ISI) that separated CS1 offset and US onset was either 0 or 5 sec. Two additional groups were also exposed to the same CS1→US pairings with either a 0 or a 5-sec ISI, and then received “backward” second-order conditioning in which CS1 was immediately followed by a novel CS2 (i.e., CS1→CS2). A trace conditioning deficit was observed in that the CS1 conditioned with the 5-sec gap supported less excitatory responding than the CS1 conditioned with the 0-sec gap. However, CS2 elicited more conditioned responding in the group trained with the 5-sec CS1-US gap than in the group trained with the 0-sec CS1-US gap. Thus, the CS1-US interval had inverse effects on first- and second-order conditioned responding. Experiment 2 was conducted as a sensory preconditioning analogue to Experiment 1. In Experiment 2, rats received the CS1?CS2 pairings prior to the CS1→US pairings (in which CS1 was again conditioned with either a 0 or a 5-sec ISI). Experiment 2 showed a dissociation between first- and second-order conditioned responding similar to that observed in Experiment 1. These outcomes are not compatible with the view that differences in responding to CSs conditioned with different ISIs are mediated exclusively by differences in associative value. The results are discussed in the framework of the temporal coding hypothesis, according to which temporal relationships between events are encoded in elementary associations. 相似文献
3.
Raymond S. Dean A.Alexander Garabedian Frank R. Yekovich 《Contemporary educational psychology》1983,8(1):28-45
Two experiments examined the effects of shifts in the modality on proactive interference in long-term memory. In Experiment 1 subjects learned a 40-word list presented in one of two forms of auditory/visual change—blocked or random. In the blocked conditions, learners were presented half the words in one modality followed by the remaining 20 words in the other modality. Subjects in random conditions also received 20 nouns in each modality, but the presentation was random. Following a delay, all subjects completed an 80-item recognition test. Analysis of these data showed a definite effect (p < .001) for the random change in modality when compared to the blocked presentation. As predicted, distinct reduction in serial position effects was found with the modality of presentation was random. In contrast, the blocked presentation produced two well-defined serial position curves. In Experiment 2 the effects of a shift in the modality of presentation on proactive interference were studied with high and low conceptual rigid subjects. Four similar prose passages were presented with a modality shift taking place in the last passage in a shift condition. Subjects in nonshift conditions were presented the passages exclusively in either the auditory or visual mode. The results showed that a shift in the modality of presentation of a prose passage provided a powerful releaser from proactive interference. The superior performance of rigid thinkers regardless of experimental group membership was explained in terms of organizational memory strategies. 相似文献
4.
Serial position effects in social transmission of food preference: Retention/demonstration intervals
Benjamin Melchor-Hipólito Gustavo Meza-Reynoso C. Edith Juárez-Maldonado Guadalupe Ortega-Saavedra Sara E. Cruz-Morales J. C. Pedro Arriaga-Ramírez 《Learning & behavior》2010,38(1):80-86
The effects of retention and demonstration intervals on serial position were evaluated in two experiments with Long-Evans
rats. A list of 3 demonstrators that had eaten one of three flavored foods was presented to naive observers. In Experiment
1, there were four groups, three groups with a retention interval compared with one group with a zero retention interval or
no retention interval. In Experiment 2, the demonstration interval was reduced. Intervals of 15, 5, 2, and 1 min were used.
In Experiment 1, primacy decreased gradually in the four groups as the retention interval was increased in duration. In Experiment
2, primacy also decreased gradually, and recency occurred with the 1-min demonstrator interval. The increase in the duration
of the retention interval reduced primacy. The reduction in the duration of the demonstration interval decreased primacy and
produced recency. 相似文献
5.
The effect of serial position was examined in a study of habituation of the vasoconstrictive orienting response in rabbits. In a procedure analogous to a recognition memory test, subjects received multiple exposures to an invariant list of stimuli before their response was assessed to an isolated item that had consistently occupied either the first, middle, or last position in the list. A reliably bowed serial-position function was obtained, with the least habituation (poorest retention) occurring for the item that had occupied the middle position in the list. The finding of both a primacy and a recency effect parallels the most general finding in studies of human memory and encourages a compatible account of habituation in infrahuman subjects. The result was discussed in terms of the opportunities for differential rehearsal of list items and contextual cues at different positions in the list. 相似文献
6.
E. J. Capaldi Donna R. Verry Timothy M. Nawrocki Daniel J. Miller 《Learning & behavior》1984,12(1):7-20
Two experiments indicated that two approaches to serial learning are too extreme—the classical view that it consists only of interitem associations and various recent views that it involves no interitem associations. The novel assumption introduced here was that phrasing cues, normally conceptualized as merely segregating long series into smaller units or chunks, may also enter into associations with items, thereby reducing interitem interference and facilitating serial learning. It was found that one item could become a signal for another item, an interitem association, or be overshadowed by a phrasing cue, such as a brightness and temporal cue, also signaling that item. The items were .045-g pellets. Rats traversed a runway for items arranged in ordered series, 14-7-3-1-0 pellets (Experiment 1) or 10-2-0-10 (Experiment 2). Complete tracking of, for example, the 10-2-0-10 series would consist of fastest running to 10 pellets and slowest running to 0 pellets. In both investigations, the interitem association overshadowed was that between 0 pellets and the subsequent rewarded item, 0 → 14 (Experiment 1) or 0 → 10 (Experiment 2). Either repetitions of the 14-7-3-1-0 subpattern (Experiment 1) or merely the terminal 10-pellet item (Experiment 2) were phrased, both methods producing identical results. Overshadowing the 0-pellet item produced superior serial learning, more rapid extinction, and, in Experiment 1, considerable elevation of responding when the brightness phrasing cue was introduced in extinction, an effect said to be conceptually identical to spontaneous recovery and one demonstrating directly that phrasing cues are in reality overshadowing cues. It was suggested that many effects attributed to forgetting may be due to unrecognized overshadowing of memory cues by phrasing cues, giving rise to exaggerated estimates of forgetting. 相似文献
7.
William H. Overman Carol McLain Gail E. Ormsby Virginia Brooks 《Learning & behavior》1983,11(4):483-488
Squirrel monkeys (Saimiri sciureus) were trained on visual recognition memory tasks in a Wisconsin General Testing Apparatus with a trial-unique procedure that used 250 objects as stimuli. In Experiment 1, acquisition of a trial-unique delayed non-match-to-sample task (DNMS) was compared with acquisition of a trial-unique delayed match-to-sample (DMS) task. The DNMS task was learned in significantly fewer trials and with significantly fewer errors. Two animals in the DNMS group demonstrated highly accurate retention of the DNMS strategy despite an 11-month hiatus in experimental testing. In Experiment 2, the same procedures were used to study the learning of lists of 3, 5, 10, or 20 serially presented items. Although the animals were able to accurately remember lists of up to 20 items, there was no evidence of serial position effects. 相似文献
8.
In making comparative judgments about pairs of stimuli that are linearly ordered, human subjects usually respond faster the greater the separation between-the-items of a test pair—the symbolic distance effect. A similar result has been obtained for associatively related items, such as the alphabet. We report evidence for a distance effect in monkeys tested with pairs of items drawn from a five-item series with which they had considerable previous experience-in a serial learning setting. This finding provides independent evidence that in learning a serial list of items, monkeys acquire knowledge about the ordinal positions of the items. Analysis of the positive results obtained in Experiment 2 and of the failure to find a distance effect in Experiment 1 suggested that in learning a serial list, monkeys construct both an associative chain representation of the series and a spatial representation, with the latter supplying the spatial markers that convey positional information. This dual coding of sequential events, which may be rather general among mammals, probably supports a variety of cognitive competencies. 相似文献
9.
Phil Reed 《Learning & behavior》2000,28(2):136-146
In four experiments, the effect of sequential exposure to a series of five novel flavors on the subsequent neophobic response
of water-deprived rats to those flavors when they were presented simultaneously was examined. After a list-test interval of
30 min and a list-interstimulus interval of 10 sec, the rats generally consumed more of the first and last flavors presented
in the initial sequence. This finding was taken to reflect the existence of primacy and recency effects. Experiment 1 provided
evidence that successive contamination can occur between flavors in the initial list, making subsequent recognition of later
flavors in the list more difficult. However, this effect was overcome by presentation of water between each flavor during
the list exposure. Experiments 2 and 4 showed that primacy was not a necessary result of successive contamination in this
procedure, by demonstrating that increasing the interstimulus interval between list items decreased the size of the primacy
effect. This result suggests that rats’ memory for serially presented items may be controlled by mechanisms different from
those typically implicated in the human verbal memory literature. In Experiment 3, the question of whether the testing procedure
adopted here could have introduced sources of artifactually produced serialposition effects was explored, but no such influence
was found. 相似文献
10.
Three experiments showed a savings procedure to be an effective and sensitive alternative to sensory preconditioning procedures as a measure of associations among neutral stimuli. Experiment 1 showed that within-compound associations developed more rapidly in reinforced appetitive serial compound conditioning when nonreinforced preexposure to the serial compound was given than when separate element or no preexposure was given. Experiment 2 showed the savings effect to be highly stimulus specific. Experiment 3 examined the facilitation of serial compound conditioning after either simultaneous or serial nonreinforced preexposure to the elements of the compound. The results of that experiment were consistent with those of analogous sensory preconditioning experiments. When preexposure involved only the two elements of the subsequently reinforced compound, serial preexposure produced more savings than simultaneous preexposure. But when preexposure involved a three-stimulus procedure like that used by Rescorla (1980b), simultaneous preexposure resulted in more savings. Advantages of the savings procedure over sensory preconditioning as a measure of association among neutral stimuli are discussed. 相似文献
11.
To begin an investigation of the cellular processes that underlie long-term memory in the nematodeCaenorhabditis elegans, it is first necessary to determine thatC. elegans is capable of retention over 24 h, and to investigate the factors that may influence the expression of long-term memory. In the present study, the effects of stimuli number, interstimulus interval (ISI), and training procedure on long-term retention of habituation were tested inC. elegans. At a long (60-sec) ISI, distributed training sessions produced long-term habituation retained for 24 h, whereas massed training sessions or training with few stimuli did not. When training was performed at a short (10-sec) ISI, long-term habituation was not detectable with testing at either a 10- or a 60-sec ISI. The long-term habituation observed after distributed training sessions at a 60-sec ISI was consistently expressed when the training procedures were varied. Thus it is clear thatC. elegans can reliably express long-term retention for distributed training sessions at a 60-sec ISI, making the system a candidate for further investigations into the cellular processes supporting memory. 相似文献
12.
Robert A. Rosellini 《Learning & behavior》1978,6(2):155-159
This article reports the reinforcer generality of the interference effect resulting from exposure to inescapable shock. In Experiment 1, rats that received inescapable shock showed weak interference with the acquisition of an appetitive operant compared to animals exposed either to escapable or no shock. In Experiment 2, the response-reinforcer contingency was degraded by introducing a 1-sec delay of reinforcement on the appetitive task. Inescapable shock produced much stronger interference with the acquisition of the operant response than in Experiment 1. The results demonstrate reinforcer generality of the debilitating effects produced by inescapable shock. 相似文献
13.
Timing of conditioned keypecking was investigated using a delay autoshaping procedure. In two experiments, the CS-US interval
(ISI) was varied and the temporal pattern of responding during unreinforced probe trials extending beyond the reinforced ISI
was recorded. Both experiments showed temporal control of keypecking at ISIs of 4, 8, and 16 sec, regardless of whether the
probe duration was held constant (Experiment 1) or covaried with the ISI (Experiment 2). Analyses showed that the timing of
keypecking was scalar. Increased responding near the end of the probe was due possibly to independent timing of the probe
duration. In a third experiment, a group of subjects trained at an ISI of 8 sec were extinguished by presentation of only
probe trials. Although the maximal response rate declined progressively, timing of keypecking did not change. 相似文献
14.
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
15.
The present experiment determined whether associative strength based upon 15 CS-US pairings at various interstimulus intervals (ISIs) could survive shifts of the ISI to influence the subsequent acquisition of the nictitating membrane (NM) CR. The choice of 15 preshift pairings was based upon previous work, which had shown that this training level produced substantial associative strength without NM CR acquisition. Consequently, this experiment, by shifting the ISI before the beginning of CR acquisition, served as an extension to traditional ISI-shift studies that have imposed the manipulation after CR acquisition. The findings of the experiment indicated that 15 preshift pairings in Stage 1 at ISIs from 250 to 4,000 msec were as effective as 15 pairings at a 500-msec ISI in determining the number of trials to the first NM CR in Stage 2 in which the training ISI was 500 msec. Moreover, 15 pairings in Stage 1 at ISIs from 250 to 2,000 msec were equivalent to 15 pairings at 500 msec in controlling the number of trials to 10 successive NM CRs in Stage 2. These outcomes demonstrate that, within a large ISI range, the associative strength based upon relatively few pairings is preserved despite various shifts of the ISI. Therefore, these results suggest that the reductions in CR performance, which have been consistently observed in traditional studies following ISI shifts, are not due to the loss of associative strength. 相似文献
16.
W. Ronald Salafia Richard W. Lambert Karen C. Host Nicolas L. Chiaia Julio J. Ramirez 《Learning & behavior》1980,8(1):85-91
In three experiments, the nictitating membrane response of rabbits was conditioned for 10 daily sessions at interstimulus intervals (ISIs) ranging from 48 to 125 msec, followed by a shift to 250 msec for 5 days. At tested ISIs shorter than 67 msec, there was no evidence of conditioning, and postshift performance revealed neither facilitation nor interference as a result of the first 10 conditioning sessions. Postshift performance of groups conditioned at preshift ISIs of 67 msec or longer revealed a gradient of increasing savings with increasing ISI. One of the groups in Experiment 1, initially conditioned at 250 msec ISI and then shifted to 48 msec, exhibited extinction of the previously well-conditioned response. Analysis of CR-onset latencies substantiated the absence of associative effects at very short ISIs. It was concluded that there is a temporal limit below which classical conditioning of the nictitating membrane response of rabbits employing forward CS-US pairing does not occur. 相似文献
17.
W. Ronald Salafia Frederick W. Mis W. Scott Terry Robert S. Bartosiak Anthony P. Daston 《Learning & behavior》1973,1(2):109-115
The study involved three experiments. The first, a parametric investigation of nictitating membrane conditioning with eight constant intertrial intervals (ITIs) between 5 and 120 sec, orthogonal to interstimulus intervals (ISIs) of 250 and 750 msec plus three temporal conditioning control groups, revealed that performance improved rapidly with increasing ITI but stabilized at relatively low ITI values. At 750-msec ISI, a decrement in performance was found at 60-sec ITI. Experiment II, using constant ITIs of 45–75 sec in 5-sec steps, at 750-msec ISI confirmed the trend toward a performance decrement around 60 sec, although the trend was weak and highly variable. Experiment III evaluated the differences in performance between constant and variable ITI, using three ITI values and three conditions of variation at each value. Findings were discussed in terms of differences in conditioning resulting from both length and degree of variation of ITI and some subtle effects which may emerge only when constant ITIs are used. 相似文献
18.
Some previous studies of visual word recognition have reported an interaction between visual field and word length (measured by number of letters), such that recognition is affected more by word length for words presented in the left than for words presented in the right visual field. However, when manipulating serial position of letters in words to measure length effects, there are also reports of symmetrical word length effects in the two visual fields. Here we report two experiments, presenting four‐ and seven‐letter words, suggesting that the serial position and length effects in the hemispheres are separable and task dependent. For tasks that rely more heavily on letter‐level processing such as letter search (Experiment 1), performance in both hemifields showed similar effects of serial position; however, when comparing four‐ and seven‐letter words, an effect of word length was evident only in the left visual field, in line with the well‐established interaction between word length and hemifield. An interaction between word length and hemifield was confirmed for the same stimuli when they were employed in a lexical decision task, which forced whole‐word processing (Experiment 2). We conclude that the effects of serial position and number of letters in the two visual fields are separable, and are selectively affected by task type. 相似文献
19.
P E Worden 《Child development》1975,46(3):687-695
Second graders, fifth graders, and adults participated in 2 experiments designed to study the effects of sorting on subsequent recall of unrelated words. 1 group sorted the items freely, while a second group was constrained to learn the sorting schemes generated by free subjects. In the first experiment, subjects sorted until they reached a criterion of organizational stability. In Experiment 2, sorting was terminated prior to reaching a stable criterion. Recall and output clustering were reduced in Experiment 2, relative to Experiment 1, because of organizational instability. No meaningful differences were found in either experiment in the sorting schemes generated by free subjects in the 3 age groups, nor was there an effect of age of yoking partner on performance of constrained subjects. This result differed from previous research, and it was concluded that the sorting technique diminished differences in organizational behavior usually found between older and younger subjects. 相似文献
20.
The serial presentation of two different CSs, with each stimulus having an 8-sec duration (S18/S28), consistently has resulted in most of the shuttlebox avoidance responses being recorded to the S2 component. Experiment 1 attempted to attenuate this serial CS, delayed-response effect by conditioning the separate components of a serial CS prior to ordering them sequentially. Ten component-training trials were administered, with subjects receiving CS-US pairing to S1 only, S2 only, or to both S1 and S2 presented on separate trials. Two CS durations (8 or 16 sec) during this phase also were compared. Subjects were then given 100 avoidance test trials using the standard serial procedure. The 10 best avoidance responders in each group were selected for analysis. Shorter avoidance latencies were obtained only for subjects receiving component conditioning to S1. CS duration was not a factor in establishing the shorter latencies. Component conditioning to S2 resulted in increasing the total avoidances. Experiment 2 increased the number of component-training trials and the generality of the findings by using a different strain of rats and by extending the testing phase of the study so that all subjects could be included in the analysis. Comparable results were obtained. The theoretical implications of these data were discussed. 相似文献