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1.
The relative importance of intramaze cues and extramaze cues in directing choice behavior on a radial arm maze was examined using a discrimination procedure which selectively rewarded rats for following only one set of cues. Rats in the intramaze group obtained food from a food cup on the end of each arm. Rats in the extramaze group obtained food from a food cup on a small platform just beyond the end of each arm. All rats were first shaped to perform correctly with the maze in a constant position. Then the maze was rotated to a new position after every choice. For rats in the intramaze group, the food moved with the arms, making intramaze cues relevant. For rats in the extramaze group, the food remained on the platforms (in the same position in the room), making extramaze cues relevant. Rats in the extramaze group performed almost perfectly during maze rotation, demonstrating that intramaze cues were not necessary to support accurate choice behavior. Rats in the intramaze group never performed better than chance, demonstrating that intramaze cues (from the rats, the reinforcement, and the apparatus) were not adequate to control choice behavior. The results of the present experiment are compared to those of other experiments describing the influence of “odor trails” or other olfactory stimuli on choice behavior in mazes.  相似文献   

2.
Pigeons were trained to symbolically match comparison stimuli to either visual sample stimuli presented on a center key or to spatial sample stimuli presented on side keys. Tests were carried out in which visual and spatial cues were simultaneously presented in compound and short-term memory was probed for either visual or spatial information. Symmetrical interference with the matching of visual and spatial components of compounds was found when the visual and spatial cues were presented on separate keys. However, when visual and spatial cues were superimposed on the same side key, no interference was observed relative to element control tests. Discussion of these findings focuses on accounts in terms of limited processing capacity, coding decrement, and receptor orientation mechanisms.  相似文献   

3.
Rats were tested in a specially constructed radial-arm maze that eliminated access to extramaze visual cues and allowed any effects of intramaze cues to be controlled. Despite this, choice accuracy was controlled by the spatial location of previously visited arms. Part of this control was attributed to vestibular or kinesthetic cues. This conclusion was corroborated by the finding that when explicit visual cues were moved from their standard (trained) spatial locations to novel locations, control of spatial choices was completely disrupted. The latter finding indicates that cues intrinsic to the rat (kinesthetic or vestibular information) and cues extrinsic to the rat (visual stimuli) operate in an integrated fashion.  相似文献   

4.
Groups of five to seven macaques were trained on repeated reversals of a visual (or spatial) discrimination habit after no pretraining, extended discrimination training, or repeated reversal training on spatial (or visual) cues. Neither sort of pretraining had a significant effect on reversal learning on the second cue. These results indicate that monkeys’ capacity to develop generalized “win-stay, lose-shift” hypotheses may have been exaggerated in previous experiments.  相似文献   

5.
After quail (Coturnix coturnix japonica) experienced a toxicosis following ingestion of water colored dark blue or light blue, the stimulus generalization of the aversion to light, medium, and dark blue water was investigated. Birds made ill following ingestion of dark blue water demonstrated a reduced aversion when tested with intensities of blue water weaker than the conditioning intensity. Birds made ill following ingestion of light blue water showed stronger aversions as a function of increasing test intensity, suggesting a stimulus intensity dynamism effect. The stimulus generalization and stimulus-intensity dynamism effects observed in this study where visual cues were used is in agreement with other results within the illness-induced aversions paradigm where rats were tested with varying concentrations of a gustatory stimulus.  相似文献   

6.
Is Visually Guided Reaching in Early Infancy a Myth?   总被引:4,自引:0,他引:4  
The issue examined was whether infants require sight of their hand when first beginning to reach for, contact, and grasp objects. 7 infants were repeatedly tested between 6 and 25 weeks of age. Each session consisted of 8 trials of objects presented in the light and 8 trials of glowing or sounding objects in complete darkness. Infants first contacted the object in both conditions at comparable ages (mean age for light, 12.3 weeks, and for dark, 11.9 weeks). Infants first grasped the object in the light at 16.0 weeks and in the dark at 14.7 weeks, a nonsignificant difference. Once contact was observed, infants continued to touch and grasp the objects in both light and dark throughout all sessions. Because infants could not see their hand or arm in the dark, their early success in contacting the glowing and sounding objects indicates that proprioceptive cues, not sight of the limb, guided their early reaching. Reaching in the light developed in parallel with reaching in the dark, suggesting that visual guidance of the hand is not necessary to achieve object contact either at the onset of successful reaching or in the succeeding weeks.  相似文献   

7.
The cognitive mechanisms involved in spatial choice when access to visual cues is restricted were examined in three experiments using male rats. A specially constructed radial-arm maze was used, in which extramaze visual cues could not be perceived from the central arena, but could be perceived from the maze arms. Choices were very accurate when the maze was not rotated during each trial, but inaccurate when the maze was rotated. This suggests that intramaze cues were involved in the control of choices. However, the data clearly showed that choices were not simply controlled by intramaze cues. Rather, control by intramaze cues interacted in a more complex manner with representations of the spatial locations of goals. Such spatial representations were involved in the control of choice despite the absence of visual spatial cues at the time choices were made.  相似文献   

8.
After a 75-sec intratrial delay, rats that had been shown the location of hidden food within a rectangular box correctly dug at that location in a second identical box, which had been moved into the same position within the room. For some rats, the opposing ends of the boxes were differentiated by distinctive corner panels; for others, there were no panels. When, during the delay interval, the turntable supporting both boxes was rotated by more than 180°, so that the second box no longer took the place of the first box within the room, the rats showed performance decrements. Nevertheless, 4 subjects selected the correct location significantly more often than the rotationally equivalent location, which corresponds to the correct location when the ends of the box are confused. The amount of rotation had no significant effect for any rat. In a final phase, the rats were denied perceptual access to cues outside the test box, which now had differentiating corner panels for all rats. Despite the distinctive panels, no rat showed a significant difference between correct digs and rotational errors; that is, no rat reliably distinguished one end of the box from the other. Results confirm previous findings that rats rely primarily on environmental shape to establish their heading. They ignore distinctive features of the surfaces that define environmental shape, even when the shape by itself is insufficient to establish a unique orientation.  相似文献   

9.
In previous studies, we have shown that adding a supplementary cue in a prior-cuing treatment may dramatically reduce its initial effectiveness. This series of experiments was aimed at testing the hypothesis that such a lack of additivity among retrieval cues could be due to the combined reactivation of memory attributes related to incompatible behavioral responses. For that purpose, rats were partially trained to reach the lighted arm (light condition; usual training condition) or the darkened arm (dark condition) of a Y-maze in order to avoid an electric foot-shock. The first experiment demonstrates that animals learned the two versions of the task similarly and that an exposure to the light similarly acts as an effective retrieval cue after a 24-h interval. In the second experiment, the effectiveness of exposure to the grid alone and to the light alone as well as to the combined light + grid cue was investigated after a 21-day training-to-test interval in the light condition, where light was related to safety and grid was associated with the shock, and in the dark condition, where both light and grid were related to the shock. The results indicate that whereas the compound light + grid cue was an ineffective retrieval cue in the light condition, it acted as an effective retrieval cue in the dark condition, supporting the hypothesis that coherence between retrieval cues is a necessary condition for effective cuing.  相似文献   

10.
Rats obtained food from the tops of vertical poles in a 5 × 5 matrix of locations. On each trial, the baited locations formed one of the two possible exemplars of a checkerboard spatial pattern. During training, locations that had been visited earlier in the trial were indicated by a visual cue. Following training, performance with and without the visual cues was compared. Spatial choices were controlled by the checkerboard spatial pattern. The visual cues enhanced the ability of rats to avoid revisits of locations. However, the visual cues did not enhance control by the spatial pattern, as would be expected if the same spatial memories were involved in avoidance of revisits and coding the location of baited locations.  相似文献   

11.
Tan LS  Bryant P 《Child development》2000,71(5):1162-1178
A novel experimental method, shift-rate recovery, was developed and used in a series of three experiments. These examined the extent to which 6-month-old infants (N = 131) find perceptual cues such as density and length useful in the discrimination of linearly arranged sets containing large numbers of objects. Results showed that infants discriminated between arrays that differ in number and density, with length held constant, when the arrays were presented either simultaneously or successively. On the other hand, infants discriminated only between arrays that differ in number and length, with density held constant, when the arrays were presented simultaneously. Infants were, however, able to perform a successive length discrimination when the arrays were continuous rather than consisting of discrete items. These findings support the conclusion that infants are able to discriminate between large number sets by relying on absolute cues such as density (but not length) and on relative cues such as optical one-to-one correspondence.  相似文献   

12.
Rats were trained in a two-lever operant chamber to discriminate the presence versus the absence of a drug. During drug sessions, the training procedure involved reinforcing presses on lever 1 with saccharin-sweetened water but not reinforcing presses on lever 2. During no-drug sessions, only presses on lever 2 were reinforced. After this discrimination was learned, each rat was trained to discriminate presence versus absence of a second drug. All rats learned this second discrimination. Finally, the rats were tested to determine whether they could still discriminate the first drug, as well as other pharmacologically related compounds; most rats could. Training drugs were phenobarbital 30–35, nicotine 0.4, amphetamine 0.4, cyproheptadine 7, phencyclidine 4, cyclazocine 1.5, fentanyl 0.04, and scopolamine 0.2 mg/kg. The results indicate that drug versus no-drug discrimination training does not disrupt discriminative control previously established with a different drug. When considered in combination with the results obtained during substitution tests conducted after drug-versus-no-drug training, the data suggest that, instead of discriminating drug cues versus no-drug cues, rats discriminate presence versus absence of particular drug cues.  相似文献   

13.
Children's ability to discriminate reflections and rotations of visual stimuli was examined within the confines of a mental rotation task. It was hypothesized that success would be affected by both characteristics of the stimulus and by the subtlety of the discrimination required. Forty 3- to 4-year-old children were directed to mentally rotate a stimulus a given number of degrees and to discriminate the appearance of the rotated stimulus from among a set of alternatives. Four stimuli differing in the number of visual orientation cues were utilized across 24 trials. A significant effect was found for number of orientation cues, and data indicated the difficulty children experienced detecting reflections, a task which bears close resemblance to the yes/no option in prototypic rotation studies. Children were only successful with a limited range of stimuli when discrimination of a reflected foil was not required. Results are discussed in light of discrepant findings about children's kinetic imagery ability and the advisability of using this particular paradigm with young Children.  相似文献   

14.
Two experiments were conducted to examine the effects of redundant and relevant visual cues on spatial pattern learning. Rats searched for hidden food items on the tops of poles that formed a square (Experiment 1) or a checkerboard (Experiment 2) pattern. The experimental groups were trained with visual cues that specified the locations of the baited poles. All groups were tested without visual cues so that any overshadowing or facilitation of spatial pattern learning by visual cues could be detected. Spatial choices were controlled by the spatial pattern and by the visual cues in both experiments. However, there was no evidence of overshadowing or facilitation of spatial pattern learning by visual cues in either experiment. The results are consistent with the idea that the representation of the spatial pattern that guides choices is not controlled by the same learning processes as those that produce associations between visual cues and food locations.  相似文献   

15.
The ability of visual CSs previously paired with flavored substances to substitute for those substances as conditional discriminative cues was examined in two Pavlovian appetitive conditioning experiments using rat subjects. In Experiment 1, a visual stimulus was first paired with the delivery of a sucrose solution. Then the rats were trained in conditional discrimination tasks in which sucrose delivery alone served as a conditional cue signaling whether or not a subsequent tone would be reinforced with food pellets. Subjects rapidly acquired discriminative performance to the tones, especially in a feature-negative condition in which sucrose delivery signaled when the tone would not be reinforced. In a subsequent test in which neither food nor sucrose was delivered, presentation of the visual CS also controlled discriminative performance to subsequently presented tones. Experiment 2 showed the ability of a visual CS to substitute for a flavored substance as a conditional cue to be highly stimulus specific. Experiment 2 also showed that a flavored substance was less effective as a conditional cue when it was made to be expected by preceding it with a previously associated visual signal than when it was made to be surprising by preceding it with a visual stimulus signaling another flavored liquid. These results indicate that CS-evoked representations of events can substitute for those events themselves in the control of previously established conditional discrimination performance.  相似文献   

16.
Control exerted by different categories of spatial information on short-distance return to shelter by young cockroach larvae and weighting of different information sources in conflict situations were investigated. In the absence of landmark cues, larvae preferred information given by path integration with kinesthetic cues over scototactic cues. When two landmark cues with a particular angular position between them were shifted 180°, larvae relied on these learned landmarks provided that their relative angular position was kept unchanged. When only one of the landmark cues was shifted 180°, larvae preferred to use the path integration system. When larvae could not use path integration cues, a modified configuration of the landmarks disturbed them. They relied on scototactic cues, although some seemed to rely on either one of the landmarks to find their shelter. Cockroaches could change the order of importance that they normally attributed to certain classes of spatial information (in increasing order: scototaxis, path integration, and learned visual landmarks) in relation to ongoing conditions.  相似文献   

17.
Experimentally naive eats learned to discriminate a pair of objects (circle and triangle) that differed in external contour, with no irrelevant cues (N = 30), with irrelevant brightness cues (N = 26), and with irrelevant size and brightness cues (N = 26). In a second experiment, naive cats were trained to discriminate bidimensional patterns (circle and triangle) with no irrelevant visual cues (N = 24) or with irrelevant size and brightness cues (N = 26). Irrelevant cues did not significantly affect the rate of shape discrimination learning in either experiment. The findings disagree with the results of several similar experiments with rats.  相似文献   

18.
Rats were given three stages of training on an eight-arm, elevated radial maze with food reward at the end of each arm. In Stage 1, rats were allowed to choose freely among the arms from the beginning of a trial. In Stage 2, three initial forced choices were followed by a series of free choices. In Stage 3, the central platform of the maze was rotated with the rat on it between the initial forced choices and the free choices. Following testing on these three stages, the animals were divided into four groups and deprived of selected senses. One group was made blind, a second anosmic, a third blind and anosmic, and a fourth was left normal. The same three stages of testing that had been conducted preoperatively then were run again post-operatively. Throughout these tests, the possible use of auditory cues was tested by presenting white noise on alternate trials. Finally, two further tests were carried out, the multiple rotations test and the removal-replacement test. The results indicated that visual cues, but not olfactory or auditory cues, played a critical role in the rat’s ability to avoid previously entered alleys. There was evidence also that rats used internal cues from kinesthetic and/or vestibular receptors when visual cues were absent.  相似文献   

19.
Rats were trained in the Morris water maze to reach a platform in darkness after they had been provided with some information on their initial location. They were given trials with (1) the light on (light condition) and (2) light followed by darkness (dark condition). In this latter condition, the dark period was preceded by either a brief (short group) or a long (long group) initial light period. Although the rats in the short group first oriented accurately toward the platform, their trajectory rapidly deviated in darkness. In contrast, the rats in the long group were able to navigate accurately over a longer distance, but finally also deviated. In transfer trials, the rats in the short group were less accurate than the rats in the long group in the dark; however, both groups performed well in light. This suggests that navigation in darkness depends not only on the use of recent visual and locomotor memory but also on the activation of an inertia-based navigation process.  相似文献   

20.
Freezing is often cited as the interfering behavior responsible for barpress conditioned suppression. However, auditory cues that precede shock can evoke more freezing than can visual cues despite producing similar suppression. In two experiments, we sought to resolve this paradox by measuring rats’ location in the box in addition to recording freezing during conditioned-suppression training to tones and lights. Tone evoked more freezing than light but similar suppression. During both cues, rats left the bar and dipper areas and moved to the lower middle and rear of the box. When the bar was then removed and the dipper entry sealed, the preference for the middle and rear of the box disappeared. Apparently, frightened rats do not simply prefer the middle and rear of our box. The fact that rats leave the bar and dipper areas equally during both auditory and visual cues explains how the two cues can foster similar suppression despite evoking different levels of freezing. But the fact that rats leave the bar and dipper areas at all remains to be explained.  相似文献   

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