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1.
In an attempt to explore the relation between the amount of variability in a stimulus and rate of habituation to that stimulus, 4 groups of infants 4 1/2--5 1/2 months of age were presented with repeated speech stimuli which were synthesized exemplars of [baba], natural exemplars of [baba] or [kaba], or novel syllables of each trial. Infants' cardiac responses to the auditory stimuli were recorded, and the number of trials to a proportional criterion of habituation of the heart-rate decelerative response was determined. Infants were found to habituate most rapidly to the synthesized [baba] stimulus which remained constant across trials and least rapidly to the speech syllables which changed from trial to trial. 相似文献
2.
The present study tracked the time course of the syllable frequency effect in French visual word recognition, by varying the strength of spreading activation between letters and phonological syllables. The frequency of phonological first syllables and the frequency of orthographic first syllables were conjointly manipulated in two lexical decision tasks. In Experiment 1, word parsing into syllable units was supported by orthographic redundancy. No interaction between orthographic and phonological syllable frequency was found. In Experiment 2, word parsing into syllables was not marked by orthographic redundancy. Results showed an interaction between orthographic and phonological syllable frequency: the syllable frequency effect was inhibitory when orthographic syllable frequency was high, whereas it was facilitatory when orthographic syllable frequency was low. Decreasing the strength of syllable activation (i.e., with orthographic syllables of low frequency and ambiguous syllable boundaries) prevented the activation of lexical competitors before target word recognition, leading to a facilitatory effect of syllable frequency. The present study provides evidence that the net effect of syllable frequency is strongly related to its time course, and that the strength of syllable activation, which depends on orthographic properties, determines the direction of the net effect. 相似文献
3.
Generic noun phrases (e.g., "Bats live in caves") are important for expressing knowledge about abstract kinds. Past work has found that parents frequently use generic noun phrases in their speech to young children. However, little is known regarding how children understand these expressions, nor which cues signal generic meaning. The present set of 5 studies examined the influence of linguistic form class (e.g., "What color are dogs?" [generic] versus "What color are the dogs?" [nongeneric]) and of pragmatic context (e.g., "What color are they?" in the presence of either a single exemplar [generic] or multiple exemplars [nongeneric]). Participants were 2-year-olds (N = 42), 3-year-olds (N = 40), 4-year-olds (N = 40), and adults (N = 51). The data indicate that by 2 years of age, children use linguistic form class, and by 3 years of age, children use pragmatic context. These findings demonstrate that young children have begun to understand the distinction between generic and nongeneric noun phrases from a very young age, and that identification of generics is signaled not by formal or pragmatic cues alone, but by a combination of information from both language form and pragmatic context. It is suggested that children make use of multiple linguistic and conceptual cues to acquire and interpret generics. 相似文献
4.
Nicholas J. Grahame Robert C. Barnet Lisa M. Gunther Ralph R. Miller 《Learning & behavior》1994,22(4):395-408
Treatments that attenuate latent inhibition (LI) were examined using conditioned suppression in rats. In Experiment 1, retarded conditioned responding was produced by nonreinforced exposure to the CS prior to the CS-US pairings used to assess retardation (i.e., conventional LI). In Experiment la, retarded conditioned responding was induced by preexposure to pairings of the CS and a weak US prior to retardation-test pairings of the CS with a strong US (i.e., Hall-Pearce [1979] LI). Both types of LI were attenuated by extensive exposure to the training context (i.e., context extinction) following the CS-US pairings of the retardation test. Experiment 2 examined the specificity of the attenuated LI effect observed in Experiment 1. After preexposure to two different CSs in two different contexts, each CS was paired with a US in its respective preexposure context. One of the two contexts was then extinguished. This attenuated LI to a greater degree for the CS that had been trained in the extinguished context. Experiment 3 differentiated the roles in LI of CS-context associations and context-US associations. Following preexposure to the CS in the training context, LI was reduced by further exposure to the CS outside the training context. This observation was interpreted as implicating the CS-context association as a factor in LI. Thus, the results of these experiments suggest that LI is a performance deficit mediated by unusually strong CS-context associations. Implications for Wagner’s (1981) SOP model and Miller and Matzel’s (1988) comparator hypothesis are discussed. 相似文献
5.
Two conditioned suppression experiments with rats were conducted to determine whether the spontaneous recovery and renewal
that are commonly observed in retroactive outcome interference (e.g., extinction) also occur in retroactive cue interference.
Experiment 1 showed that a long delay between Phase 2 (the interfering phase) and testing produces a recovery from the cue interference
(i.e., the delay enhanced responding to the target cue trained in Phase 1), which is analogous to the spontaneous recovery
effect observed in extinction and other retroactive outcome interference procedures. Experiment 2 showed that, when target and interfering cues are trained in separate contexts and testing occurs in a different but familiar
context, a recovery from the cue interference is also observed (i.e., the context shift enhanced responding to the target),
which is analogous to ABC renewal from extinction. The results are discussed in terms of the possibility that similar associative
mechanisms underlie cue and outcome interference. 相似文献
6.
Water-deprived rats were used to investigate the effects of training a CS in more than one context on conditioned lick suppression. In each experiment, partial reinforcement of the CS was intermingled with unsignaled presentations of the US. In Experiment 1, subjects were either trained in one context alone, trained consecutively in two contexts (such that all training in one context occurred prior to any training in the second context), or trained alternately in two contexts. Following training, the first context, the second context, or neither context was extinguished. Testing of the CS occurred in a third (neutral) context. To the extent that either training context became established as a comparator stimulus for the CS, the comparator hypothesis (Miller & Matzel, 1988) predicts an increase in excitatory responding to the CS following extinction of that context. Subjects trained in a single context exhibited appreciable fear of the CS only when the CS’s training context had been extinguished. Additionally, subjects trained consecutively in the two contexts showed increased fear of the CS following extinction of the second, but not the first training context (i.e., a recency effect). Subjects trained alternately in the two contexts showed no increased fear of the CS as a result of either context alone being extinguished. In Experiment 2, subjects trained alternately in two contexts showed increased fear of the CS only when both training contexts were extinguished, suggesting that both training contexts had become comparator stimuli. These data indicate that multiple training contexts can either compete or act synergistic-ally in modulating responding to a Pavlovian trained CS as a function of the order of training in the different contexts. 相似文献
7.
Infants 9-11 months of age were tested for their discrimination of changes in the melodic contour (direction of successive pitch changes) of brief melodies in the context of discernible variations in key (different absolute frequencies, same intervals) or interval size (different absolute frequencies and frequency ratios, same contour). Infants detected contour changes in both variable contexts, suggesting that they categorize sequences of sounds on the basis of global, relational properties such as melodic contour. Implications of such processing strategies for infants' perception of running speech are considered. 相似文献
8.
Latent inhibition, which refers to attenuated responding to a conditioned stimulus (CS) after CS-unconditioned stimulus (CS-US) pairings as a result of CS-alone presentations prior to the pairings, is often attenuated if preexposure and conditioning occur in different contexts (i.e., it is context specific). Here we report two conditioned lick suppression experiments, using rat subjects, that examined whether manipulations known to attenuate the context specificity of extinction could also eliminate the context specificity of latent inhibition. Context specificity of latent inhibition was eliminated when the CS was preexposed in multiple contexts (Experiment 1) and when the CS was massively pre-exposed in the training context alone (Experiment 2). These results and their practical implications are discussed in the framework of contemporary theories of latent inhibition. 相似文献
9.
In 4 studies, 7.5-month-olds used synchronized visual-auditory correlations to separate a target speech stream when a distractor passage was presented at equal loudness. Infants succeeded in a segmentation task (using the head-turn preference procedure with video familiarization) when a video of the talker's face was synchronized with the target passage (Experiment 1, N = 30). Infants did not succeed in this task when an unsynchronized (Experiment 2, N = 30) or static (Experiment 3, N = 30) face was presented during familiarization. Infants also succeeded when viewing a synchronized oscilloscope pattern (Experiment 4, N = 26), suggesting that their ability to use visual information is related to domain-general sensitivities to any synchronized auditory-visual correspondence. 相似文献
10.
Using a picture pointing task, this study examines toddlers’ processing of phonological alternations that trigger sound changes in connected speech. Three experiments investigate whether 2;5‐ to 3‐year‐old children take into account assimilations—processes by which phonological features of one sound spread to adjacent sounds—for the purpose of word recognition (e.g., in English, ten pounds can be produced as te[mp]ounds). English toddlers (n = 18) show sensitivity to native place assimilations during lexical access in Experiment 1. Likewise, French toddlers (n = 27) compensate for French voicing assimilations in Experiment 2. However, French toddlers (n = 27) do not take into account a hypothetical non‐native place assimilation rule in Experiment 3, suggesting that compensation for assimilation is already language specific. 相似文献
11.
Rats trained in one context to use stimuli arising from food deprivation as discriminative signals for shock were tested in other contexts to assess the basis of conditioned responding (i.e., freezing or behavioral immobility). In Experiment 1, discriminative control by 24-h food-deprivation cues failed to promote transfer responding in a test context that had no association with shock. This indicated that food deprivation cues had little direct excitatory power. However, transfer of behavioral control by 24-h food-deprivation cues was obtained in a context paired with shock only when the rats were 19 h water deprived. This finding agrees with the idea that food-deprivation cues become conditioned modulators of the capacity of external stimuli to activate their association with an unconditioned stimulus. In Experiment 2, rats trained to use 24-h food-deprivation cues as signals for shock exhibited significantly greater transfer performance when the transfer context had undergone partial extinction relative to when the transfer context had undergone only simple excitatory training. This finding with deprivation cues and transfer contexts (1) paralleled earlier results obtained with discrete (auditory and visual) conditioned modulators and transfer targets, and (2) posed difficulties for associative summation and generalization interpretations of transfer performance. 相似文献
12.
The context??s role in Pavlovian conditioning depends on the trial spacing during training, with massed trials revealing a function akin to that of discrete stimuli, and spaced trials revealing a modulatory function (Urcelay & Miller, Journal of Experimental Psychology. Animal Behavior Processes, 36, 268?C280, 2010). Here we examined the contextual determinants of a common but largely ignored effect: attenuated conditioned responding with extended reinforced training (i.e., a postpeak performance deficit [PPD]). Contextual sources of PPDs were investigated in four fear-conditioning experiments with rats. In Experiment 1, as the number of reinforced trials increased, conditioned responding decreased, even when testing occurred outside the training context. Experiment 2 revealed opposing influences of context on the PPD based on trial spacing, which interacted with whether testing occurred in the training context. This finding reconciles Experiment 1??s results with previous data (Bouton, Frohardt, Sunsay, Waddell, & Morris, Journal of Experimental Psychology. Animal Behavior Processes, 34, 223?C236, 2008). Experiment 3 suggested that extended training with these parameters did not lead to habituation to conditioned or unconditioned stimuli. In Experiment 4, few or many massed training trials were followed orthogonally by context extinction or no context extinction. After many pairings, context extinction reduced the PPD (i.e., enhanced responding), suggesting a competitive role of the context. These results, together with prior data suggesting that context modulates expressions of the PPD, are consistent with the view that contexts can play two distinctly different roles. 相似文献
13.
The effects of element or compound preexposure and retention interval were examined in three experiments with the taste-aversion paradigm. In Experiment 1, preexposure to the elements of a compound flavor produced less latent inhibition to the compound than did preexposure to the compound itself when a 1-day preexposure-conditioning interval was used. However, preexposing the elements or the compound resulted in equivalent latent inhibition effects when a 21-day retention interval was used. In Experiment 2, a similar pattern of results was observed when the conditioning-test interval was manipulated. Experiment 3 explored the effect of element or compound preexposure when preexposure and test were carried out in different contexts. Attenuated latent inhibition following preexposure to the elements was found when preexposure and test were carried out in the same context. In contrast, preexposure to the elements resulted in as much latent inhibition as did preexposure to the compound when the context was switched from preexposure to testing. The implications of these findings for a retrieval-oriented view of latent inhibition are discussed. 相似文献
14.
In Experiment 1, 12 pigeons were given eight sessions of VI single stimulus training with a color in a particular context followed by eight sessions of similar training with a line angle in another context. On the next day, half of the subjects were tested for wavelength and angularity generalization in each of the two contexts, a procedure that was thus consistent with training for one dimension and inconsistent for the other. The subjects made significantly more responses to each training stimulus under the consistent context condition, but there was no difference in absolute or relative generalization slopes. In Experiment 2, 12 pigeons were trained as in Experiment 1, but during generalization testing they were exposed to both contexts sequentially. Under the consistent context condition, the subjects responded more to the two training stimuli and yielded sharper absolute and relative wavelength generalization gradients: Under the inconsistent context condition, responding to the training wavelength was substantially disrupted. Thus, under appropriate testing conditions, contextual control over both the amount and the selectivity of responding can be demonstrated. 相似文献
15.
Retroactive cue interference refers to situations in which a target cue X is paired with an outcome in phase 1 and a nontarget cue Z is paired with the same outcome in phase 2, with less subsequent responding to X being seen as a result of the phase 2 training. Two conditioned suppression experiments with rats were conducted to determine whether retroactive cue interference is similarly modulated by a manipulation that influences retroactive outcome interference (e.g., extinction). Both experiments used an ABC renewal-like design in which phase 1 training, phase 2 training, and testing each occurred in different contexts. Experiment 1 found that training the target association in multiple contexts without altering the number of training trials during phase 1 decreased retroactive cue interference (i.e., increased responding consistent with the target association). Experiment 2 found that training the interfering association in multiple contexts without altering the number of interference trials during phase 2 increased retroactive cue interference (i.e., decreased responding consistent with the target association). The possibility of similar mechanisms underlying cue interference and outcome interference is discussed. 相似文献
16.
17.
The uneven distribution of knowledge within modern societies requires a reliance on sources (e.g., reference books, teachers,
the Internet) in addition to own experience. Most scientific issues are far too complex to be understood in any depth by laypersons.
Successful knowledge acquisition comprises the ability to vary the amount of sources used and to appreciate different sources
in different contexts. Epistemological beliefs (i.e., learners’ beliefs on the nature of knowledge and knowing) might affect
this task. We report research on secondary school students’ decisions about the amount of sources they would use and their
source appreciation (the perceived usefulness of several sources), the impact of epistemological beliefs on such decisions,
and their adaptivity to the contextual circumstances of the information search. After exposure to an experimentally induced
epistemological sensitization, the students provided information on how they would proceed to confirm given knowledge. Study
1 explored the amount of sources (source quantity and access approaches). Study 2 investigated the perceived usefulness of
several sources (source appreciation). Results showed an increase in the amount and appreciation of sources in a high-involving
context and after sophisticated sensitization. More sophisticated beliefs led to a larger increase in the amount of sources
in a high-involving context. Furthermore, epistemological beliefs predicted the difference in source appreciation between
contexts. Conclusions are drawn for the use of sensitization and the teaching of digital literacy in schools. 相似文献
18.
In 2 experiments we asked whether training in multiple contexts could eliminate context-dependent memory retrieval at 6 months as it does for adults. We found that 24-hour retention was disrupted when infants were trained in one context and tested in another but not when they were trained in multiple contexts prior to testing in a novel context (Experiment 1). After a long delay, however, training in multiple contexts did not facilitate memory retrieval in a novel context: An otherwise effective retrieval cue (the training mobile) did not alleviate forgetting 3 weeks later when it was presented in a novel context (Experiment 2). These findings demonstrate that multiple learning contexts can override the debilitating effects of an altered context on memory retrieval at 6 months, but only over the short term. The resistance of older memories to retrieval in novel contexts after long periods of disuse may be adaptive, insuring that potentially inappropriate or irrelevant memories will not be expressed. 相似文献
19.
Maternal behaviors within mother-infant games were examined to determine the amount, type, and functional value of maternal helping behaviors. 17 mother-infant pairs were videotaped on monthly visits from 8 to 16 months as they played 5 separate games. 2 of these games, roll the ball and peekaboo, were analyzed in terms of "rounds" of each game. Results show that dyads play more rounds of both games in the first months that infants perform game-relevant behaviors (e.g., returning a ball, performing uncovering or covering-uncovering). Maternal attention-getting and physical "stage-setting" behaviors occur in the early rounds of both games. In roll the ball, maternal hands-out and reinforcement behaviors increase in the months after the child begins to return the ball, while the percentage of rounds in which dyads play nonreturn variants decreases. Infants are more likely to return a ball when mother holds out her hands than when she does not. Infants are also able to perform returning or uncovering in game contexts before they perform similar behaviors in cognitive tests. The general similarity of findings in the peekaboo and roll-the-ball games, in spite of differences in the amounts of scaffolding, attention-getting, stage-setting, and reinforcement behaviors between the 2 games, indicates that the types and functions of maternal helping behaviors may be generalizable to other contexts of mother-infant interactions. 相似文献
20.
Michael S. Fanselow 《Learning & behavior》1990,18(3):264-270
When a rat was placed in a chamber and shortly thereafter received a single footshock, it showed conditional freezing upon re-exposure to that chamber but not a different one (Experiment 1). Experiments 2–4 showed that the probability of this freezing decreased linearly with decreases in the delay between placement in the chamber and shock delivery. With very short delays (e.g., less than 27 sec), there was no freezing. Experiments 2 and 3 demonstrated that a 2-mm pre-exposure to the chamber, 24 h prior to shock delivery, reduced the minimum delay necessary to successfully condition freezing. Experiment 4 demonstrated that shorter delays were successful in conditioning freezing if a salient tone was a component of the contextual stimulus. The changes in freezing caused by delay interval and preexposure did not simply reflect the total time in the context, suggesting that there may be two requirements that place temporal restrictions on the conditioning of the freezing response. One is satisfied by sufficient exposure, whether or not that exposure is contiguous with shock. The second requirement is for a small amount of context exposure that is contiguous with shock. 相似文献