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1.
Presentations of a visible moving object immediately suppressed ongoing distress vocalization in newly hatched ducklings, but presentations of only the auditory features of the object initially had no effect. However, as the ducklings received more and more exposure to the visible moving object, the object’s auditory features gradually acquired the ability to suppress distress calls themselves. These auditory features failed to develop suppressive properties in ducklings which received prolonged exposure to those features but never saw the object in motion. The gradual acquisition of behavioral control by the auditory features of a moving object is taken to represent the essence of the imprinting process.  相似文献   

2.
Three experiments investigated the fact that the static visual features of an imprinting object (its color, size, and shape characteristics, as represented by the object remaining stationary during its presentation) can gradually acquire control over filial behavior by virtue of their repeated spatial-temporal pairing with visual motion—an effect that has been interpreted as a process of classical conditioning. Experiment 1 found that the static features can acquire control if they are made conspicuous in some other, nonmovement way (i.e., by manipulating the relative illumination of the imprinting object). Further experiments then failed to find any qualitative difference between the behavioral control developed by conspicuous but static aspects of a duckling’s environment and the control developed by the static features of a moving object, either in terms of persistence of the acquired control (Experiment 2) or in terms of possible restrictions imposed by the sensitive period for imprinting (Experiment 3). Taken together, these results support the plausibility of a perceptual learning hypothesis, although the classical conditioning view was not itself contradicted. The present findings are also relevant to the broader issue of whether any valid distinctions exist between the behavioral control exerted by static aspects of a precocial bird’s environment and the control exerted by animate, presumably social stimuli.  相似文献   

3.
Ducklings (Anas Platyrhynchos domesticus) older than the so-called critical period (Days 1 and 2 posthatch) were exposed to an imprinting stimulus after various experimental histories. The first study found that in previously isolated 10-day-old subjects the stimulus exhibited the same capacity to reinforce an operant response and to generate a burst-like pattern of responding as in ducklings imprinted to it on Day 1. In Experiment 2, an imprinting stimulas exhibited reinforcing capacities in 5 to 10-day-old ducklings that had previously been imprinted to a different stimulus. Most of these ducklings came to prefer the second imprinting stimulus over the first. Experiment 3 revealed that in 5-day-old ducklings with a prior history of imprinting to a different stimulus, the otherwise neutral features of a new imprinting stimulus acquired the same kind of persistent control over distress vocalization that they acquire in younger, naive subjects. In all these studies, the only difference between imprinting in older vs. younger subjects was that in older subjects a novel imprinting stimulus initially evoked fear reactions rather than filial behavior. These findings contradict the traditional view of imprinting as an irreversible process that occurs only during a brief critical period, but are entirely consistent with a reinforcement model of imprinting.  相似文献   

4.
Four-day-old ducklings received visual-plus-tactile exposure to one novel object and visual-only exposure to a different novel object. In a subsequent test, strong suppression of ongoing distress vocalization was exerted only by the object to which visual-plus-tactile exposure had been given. With these results, the experimental conditions under which physical contact is known to facilitate the initiation of imprinting are extended to include subjects that are past the sensitive period.  相似文献   

5.
Peking ducklings were reared for 1–2 weeks with either 9 or 12 companions, which were either conspecifics or imprinting stimuli (blocks of foam rubber). They were then tested for their tendency to distress call as the number of companions was reduced systematically. Consistent with prior research, ducklings reared with conspecifics modulated their distress calling as a function of both the number of companions with which they were reared and the number of companions with which they were tested. In contrast, ducklings reared with moving imprinting stimuli gave few if any distress calls, regardless of the number of stimuli with which they were reared or tested, as long as at least one imprinting stimulus was present. The difference in responding did not reflect just a lack of attachment to the imprinting stimuli, since when all stimuli were removed these ducklings gave as many distress calls as the ducklings that had all their conspecifics removed. Finally, ducklings reared with stationary imprinting stimuli displayed an erratic pattern of distress calling when the number of test stimuli was manipulated. These latter ducklings appeared to be less strongly imprinted than the ducklings reared with either conspecifics or moving imprinting stimuli. Implications for understanding duckling perception of brood size and thenature of sibling vs. filial imprinting are examined.  相似文献   

6.
Environmental novelty was manipulated in imprinted ducklings by varying the illumination level of the experimental apparatus. Bright illumination disrupted filial behavior in subjects that had received little prior exposure to the imprinting object, with approach being suppressed more when the object was stationary than when it was moving. In subjects with prolonged prior imprinting exposure, bright illumination enhanced filial behavior. These effects can be understood if one assumes that environmental novelty has an energization effect while also eliciting responses that are incompatible with filial behavior.  相似文献   

7.
Repeated exposure to a single target type (sequential priming) during visual search for multiple cryptic targets commonly improves performance on subsequent presentations of that target. It appears to be an attentional phenomenon, a component of the searching image effect. It has been argued, however, that if searching image is an attentional process, sequential priming should also interfere with performance on subsequent nonprimed targets, and such interference has never been unequivocally demonstrated. In blue jays (Cyanocitta cristata) searching in an operant apparatus for targets derived from images of cryptic moths, detection performance was strongly facilitated in the course of a sequential prime but was relatively unaffected by sequences of mixed target types. Detection accuracy in subsequent probe trials was enhanced by priming with targets of the same type, whereas accuracy on cryptic probes following priming with a more conspicuous target was significantly degraded. The results support an attentional interpretation of searching image.  相似文献   

8.
Rats received training in which two auditory target stimuli, X and Y, were signaled by two visual stimuli, A and B, and followed by food (i.e., A-->X+, B-->Y+). The test consisted of presentations of X and Y preceded either by the same signal as during training (same trials: A-->X, B-->Y) or by the alternative signal (different trials: A-->Y, B-->X). After 8 training sessions, the animals responded less on same trials than on different trials; this effect was significantly reduced after 24 training sessions. In two additional experiments, animals that had also experienced presentations of A and B alone, either before or during training, showed the opposite pattern of results, responding more on same trials than on different trials. These results are interpreted as being due to the interaction between the effects of occasion setting and negative priming (see Wagner, 1981).  相似文献   

9.
Lexical priming was assessed in children with reading disability (RD) and in age-matched controls ( M = 11.5 years), in visual and auditory lexical decision tasks. In the visual task, children with RD were found to have deficits in semantic (SHIP–BOAT), phonological/graphemic (GOAT–BOAT), and combined (FLOAT–BOAT) priming. The same pattern of semantic priming deficits also occurred in auditory lexical decisions, suggesting that the semantic deficits are not confined to reading. Children with RD also showed less priming than reading-age matched controls, suggesting that their priming deficits are not simply due to lower reading level but are due to the reading disability in particular. These semantic deficits may contribute to both the word reading and the comprehension problems seen in children with RD.  相似文献   

10.
Three experiments evaluated an alternative to accounts of positive conditioned suppression that stress central (i.e., motivational or emotional) states. This “competing-response” interpretation was tested by analyzing directed movements that develop in rats during a visual or an auditory stimulus (CS) that signals an appetitive reinforcer (US) in a situation where the subject is also emitting an instrumental response for food. In each experiment, positive conditioned suppression (i.e., a reduction in the rate of such instrumental responding during CS presentations) was accompanied by responses directed toward the CS source and/or the US-delivery site. In Experiment 1, a diffuse (auditory) CS signaled a US delivered at some specific place in the chamber and rats approached the US-delivery site during CS. In Experiments 2 and 3, the spatial proximity of a localized visual CS and US-delivery site determined whether CS-directed or US-directed behavior predominated during the CS. The results suggest that the topographies of conditioned responses on any positive conditioned suppression procedure depend upon the spatial arrangements of features that elicit and support these behaviors. They further suggest that the identification of these features and their spatial arrangements is necessary for the analysis of appetitive classical-instrumental interactions.  相似文献   

11.
Cats’ and dogs’ search behavior was compared in different problems where an object was visibly moved behind a screen that was then visibly moved to a new position. In Experiments 1 (cats) and 2 (dogs), one group was tested with identical screens and the other group was tested with dissimilar screens. Results showed that in both species, search behavior was based on processing of spatial information rather than on recognition of the visual features of the target screen. Cats and dogs were unable to find the object by inferring its invisible movement. They reached a high level of success only if there was direct perceptual evidence that the object could not be at its initial position. When the position change was indicated by an indirect cue, cats searched more at the object’s initial than final position, whereas dogs searched equally at both positions. Interspecific similarities and differences are interpreted in terms of the requirements for resetting working memory.  相似文献   

12.
The quality of implicit morphological knowledge in adult Hebrew readers with developmental dyslexia was investigated. The priming paradigm was used to examine whether these adults extract and represent morphemic units similarly to normal readers during online word recognition. The group with dyslexia as a whole did not exhibit priming with visual presentation as opposed to both age- and reading-level controls. Priming was absent when the prime and target words shared a morpheme and even when the prime and the target were identical. Only the students with phonological dyslexia, who exhibited relatively good performance in the orthographic judgment task, exhibited repetition priming but not morphological priming. Strong repetition and morphological priming effects were found for participants with dyslexia when the stimuli were auditory. The implications of the dissociation between visual and auditory priming for the locus of the deficit in morphological processing during word recognition are discussed.  相似文献   

13.
The onset of motion was used to study stimulus-driven visual attention in 14-week-olds. The movement of an object did not capture attention reflexively at 14 weeks of age. The attention-getting properties of a moving stimulus depended significantly on its color in combination with the colors of other objects in the visual field. Specifically, detection of a green moving target was masked in the presence of mixed red and green static objects. No such masking was observed when the moving target was red or when the green target moved in a visual field that was populated only with green objects. The same effect was observed to a lesser extent when the green bars were replaced with gray bars. The number of distractors in the visual field exerted an effect on the accuracy of detection only when their appearance in the visual field was coincident with the onset of target motion. Attention to motion at this age is not independent of the structure of the visual field; chromatic preferences play a role in how readily infants attend to a moving object. These effects may be mediated by a difficulty in disengaging attention (from distractors) or in suppressing attention to competing objects once attention is engaged on a target.  相似文献   

14.
The effects of visual grouping strategies involving animated and static graphic presentations on selective attention were studied. Also studied was the ability of students to learn a scientific rule presented incidentally in an animated sequence. A total of 39 fourth-graders participated in an introductory lesson on Newton's laws of motion. Two levels of Visual Presentation (Static Graphic, Animated Graphic) were crossed with two levels of Visual Grouping (Grouped, Ungrouped). A within-subjects factor consisted of two levels of Learning Intent (Intentional, Incidental). Results showed that students given animated presentations of lesson content outperformed students receiving static presentations, but only when the animated lesson frames were presented in groups, or “chunks,” of textual and visual sequences. Results also showed that students were able to successfully extract information pertaining to an application of Newton's second law incidentally presented in animated sequences. These latter results replicate earlier findings.  相似文献   

15.
4-month-old infants held 2 rings, 1 in each hand, out of view. The rings moved rigidly together and were either the same (Experiment 1) or different (Experiment 2) in substance, weight, texture, and shape. After haptic habituation to a ring display, patterns of preferential looking to visibly connected vs. separated rings provided evidence that the infants perceived the rings in both experiments as parts of one connected object. This perception was no weaker when the rings differed in shape and substance, even though infants were shown (Experiment 3) to detect that difference. In the haptic mode, as in the visual mode, infants appear to perceive object unity by analyzing motion but not by analyzing figural goodness. The findings suggest that an amodal mechanism underlies object perception.  相似文献   

16.
Acquisition, extinction, and transfer of facilitation were explored in a series of experiments with C57BL/6J mice. With a procedure in which an auditory target was followed by food only in the presence of a visual facilitator, Experiments 1—4 showed that the facilitator promoted magazine entries to the auditory target. This enhancement effect was eliminated by training the facilitator as a conditioned inhibitor (Experiments 1 and 3B). Enhancement was also reduced by nonreinforced presentations of the facilitator in a discrimination procedure (Experiment 1) and by simple nonreinforcement of the facilitator (Experiments 2, 3A, and 4). In contrast to the results obtained with a facilitator, simple nonreinforcement of an inhibitor, a visual cue that had signaled when an auditory target would not be reinforced, did not reduce its ability to modulate responding to that target (Experiment 4). However, both the facilitator and the inhibitor were found to transfer their modulatory effects to other targets (Experiment 4). Finally, mice demonstrated no evidence of differential responding on a biconditional discrimination procedure in which one auditory target (A1) was reinforced in the presence of one visual stimulus (L1) but not in the presence of another (L2), and a different auditory target (A2) was reinforced in L2 but not in L1 (Experiment 5). The implications of these results for analysis of the function of a facilitator are discussed.  相似文献   

17.
电视广告的整体美主要由视觉美、听觉美、文学美构成。这三类美的特征主要区别在于:视觉美的各个部分在空间中并存,具有直观可感性;听觉美的各个部分在时间中承续,可感但不具象;文学美不可感知,只能意会,其内容超重于形式,而视觉美和听觉美则可以感知,其形式超重于内容。三类美在电视广告中融合成综合美,给受众造成了多种多样的审美效果,主要有优美效果、壮美效果、喜剧性效果,有时还有悲剧性效果。  相似文献   

18.
Separate groups of pigeons were trained to perform symbolic delayed matching to sample with auditory and visual sample stimuli. For animals in the auditory group, ambient tones that varied in frequency served as sample stimuli; for animals in the visual group, ambient red and green lights served as sample stimuli. In both cases, the sample stimuli were mapped onto the yellow and blue comparison stimuli presented on left and right pecking keys. In Experiments 1 and 2, it was found that visual and auditory delayed matching were affected in the same ways by several temporal variables: delay, length of exposure to the sample stimulus, and intertrial interval. In Experiments 3, 4A, and 4B, a houselight presented during the delay interval strongly interfered with retention in both visual and auditory groups, but white noise presented during the delay had little effect in either group. These results seem to be more in line with a prospective memory model, in which visual and auditory sample stimuli are coded into the same instructional memories, than with a model based on concepts of retrospective memory and modality specificity.  相似文献   

19.
Pigeons received food for responding on a fixed-interval 32-sec schedule divided into three equal parts, each correlated with a distinctive, response-independent, visual stimulus. Response rate was very low during the first two thirds of the interval but high during the terminal third. When a response-dependent brief stimulus correlated with the terminal third was arranged for each response in the presence of the stimuli correlated with the first two thirds, response rate was enhanced, especially in the middle third. However, response rate was suppressed when each response in the presence of the stimulus correlated with the final third produced a brief stimulus correlated with the initial third. A similar suppressive effect occurred when each response produced a brief stimulus correlated with the middle third. Response suppression decreased over successive response-dependent brief-initial-stimulus manipulations. The results were interpreted in terms of reinforcement, punishment, and discriminative stimulus control by visual stimuli correlated with parts of a fixed-interval schedule.  相似文献   

20.
We present a domain-general framework called constrained attentional associative learning to provide a developmental account for how and when infants form concepts for animates and inanimates that encapsulate not only their surface appearance but also their movement characteristics. Six simulations with the same general-purpose architecture implement the features of the theory to model infant behavior in learning about objects' motion trajectory, their causal role, their onset of motion, and the initial mapping between a label and a moving object. Behavioral experiments with infants tested novel hypotheses generated by the model, showing that verbal labels initially may be associated with specific features rather than overall shape. Implications of the framework and model are discussed in relation to the mechanisms of early learning, the development of the animate-inanimate distinction, and the nature of development in the first years of life.  相似文献   

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