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1.
Social memory was investigated in the context of a spatial working memory task. Pairs of rats were tested in an eight-arm
radial maze. Under most conditions, there was a tendency to choose maze locations that had been visited earlier by the other
rat. The possibility that this tendency is produced by common preferences for particular maze locations was ruled out. An
opposite tendency to avoid visits to locations that had been visited earlier during the trial by another rat was found only
when the maze location contained two pellets (rather than an undepletable supply), the rats’ ability to see each other in
the maze was restricted to the central arena, and the maze location had been previously visited by the focal rat. The amount
of food available in maze locations did not otherwise modulate social influences on spatial choice. The results indicate that
memory for a rat’s own previous choices is combined with memory for the choices made by another rat. 相似文献
2.
An attempt was made to disrupt memory for spatial information by interpolating a task of high similarity to the to-be-remembered task during a long retention interval. Rats were trained in an 8-arm maze in which choosing each arm without repetition was the optional strategy. A 4-h delay was imposed between the 4th and 5th choices. At various times during the retention interval, the rats ran a second identical maze located in another room. No evidence of retroactive interference was observed. In the second experiment, the rat was required to remember the interpolated spatial task during the retention test. This was accomplished by allowing the rat to make four choices in the first maze and then, after a variable period of time, four choices in the second maze. Four hours after exposure to each maze, retention was tested. Choice accuracy on the retention tests was high and equivalent on both mazes. Requiring the rat to remember which arms it had visited in a second maze did not impair memory for the first maze. These results demonstrate that rats can segregate spatial memories established in different contexts with considerable proficiency. 相似文献
3.
Rats experienced a spatial pattern of baited and unbaited arms in an eight-arm radial maze. The spatial pattern remained constant
over trials, but the spatial locations that were baited varied unpredictably. Although there was no evidence of control by
the spatial pattern during free choice training trials, the rats’ ability to locate baited arms in forced choice test trials
was superior to that of animals in a control condition for which maze arms were not baited in a consistent spatial pattern.
This is consistent with the results of experiments showing that spatial choices by rats in a pole box maze are controlled
by abstract spatial patterns. 相似文献
4.
Siamese fighting fish (Betta splendens) were tested in aquatic versions of radial arm mazes. In the first experiment, the fish were trained to find tubifex worms in an eight-arm maze in which the optimal strategy was to choose each arm once without repetition. After initial training, the fish entered approximately 6.63 different arms in eight choices, showing a strong tendency to choose sequences of adjacent arms, moving about the maze in a Stereotypic direction. This algorithmic response pattern was not, however, sufficient to predict the high performance level of the fish. In the second experiment, a delay of .5 or 5 min was interposed between the fourth and fifth choices. Similar Stereotypic patterns continued in Experiment 2, but choice accuracy following the longer delay declined to a level not significantly above chance. In the third experiment, different fish were tested in a three-arm maze, reinforced either for returning from the second arm to the arm in which they had most recently been fed (win-stay) or for visiting a third arm (win-shift). The fish were significantly faster at acquiring the win-shift contingency than the win-stay contingency. These results demonstrate that solution of spatial tasks depends on the interaction of appropriate behavioral strategies and cognitive capacities that may have little generality across species. 相似文献
5.
Rats were trained in a three-alternative spatial delayed matching-to-sample task in a starburst maze. Samples consisted of rewarded forced choices of one arm, and retention was indicated by rats’ returning to that arm after a 90-sec delay. If a rat made an error on its first choice, it was returned to the start compartment and allowed a second choice. Unlike in previous experiments with this task, all three arms were available during the animals’ second choices. The rats tended to perseverate in their second choices by returning to the arm that they had erroneously visited on their first choice. In Experiment 1, the accuracy of second choices following first-choice errors was below chance during the first block of sessions, when a 90-sec delay intervened between the first choice and the second choice, and at chance during the second block of sessions, when a short (5–6 see) delay intervened between first and second choices. In Experiment 2, long-delay and short-delay sessions were randomly presented to naive subjects. Similar results were obtained. In both experiments, the tendency to repeat the erroneous first choice was greater when long delays separated the two choices than when short delays were used. The results suggest that rats make their first-choice errors because they erroneously encode or remember the location of the sample and that they base their second choices on the same erroneous-memory. The increase in perseveration at long delays implies some kind of rehearsal-like mechanism that slows forgetting of the memory controlling the first choice. 相似文献
6.
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
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.
William A. Roberts 《Learning & behavior》1981,9(4):566-574
Two experiments were carried out in which rats first were given four forced choices on an eight-arm radial maze, then were given interpolated maze experiences, and finally were given a free choice retention test on the first maze. In Experiment 1, interpolated experiences consisted of forced choices made on one, two, or three other mazes, each placed in a different room. Retroactive inhibition (RI) was not found with one and two interpolated mazes but was found with three interpolated mazes. In Experiments 2a and 2b, an attempt was made to produce RI within a single context by using two mazes placed side by side or on top of one another and by using interpolated forced choices that were different, random, or the same with respect to forced choices onMaze 1. These conditions failed to yield any evidence of RI. In Experiment 2c, forced choices were followed by interpolated direct placements on the same maze on different, random, or the same maze arms, and retention tests revealed RI under these conditions. It was concluded that rats encode memories of specific places visited in space and that RI will arise only if (1) memory is greatly overloaded with interpolated information or (2) an interpolated visit is made to exactly that position in space to which an animal must travel in order to achieve a correct choice on the retention test. 相似文献
9.
In Experiment 1, rats foraged for food in six successive phases with 8, 16, 24, 32, 40, and 48 arms attached in random locations to a large radial maze. The percentage of novel choices appeared to be determined more by spatial proximity than by number of arms. In Experiment 2, rats foraged for food in four successive phases with 8, 16, 24, and 48 arms attached to the maze in spread-out or tight configurations. Performance was poor in the tight configurations regardless of the number of arms. Performance was excellent in the 8-arm spread-out condition but declined as 16 and, then again, 24 arms were added. Thus, spatial separation, not number of locations, was the chief determinant of performance in the first two experiments. In Experiment 3, in successive phases, 8, 16, 24, 32, 40, 48, 16, and 8 food towers were set in a circle on the floor, with the spatial separation between adjacent towers held constant at 33 cm. The percentage of novel choices declined as 8 towers became 16 and did not change again with 24, 32, 40, or 48 towers in place but then increased again as 16 towers became 8. In Experiment 4, in successive phases, 8, 16, 24, and 32 food towers were set in a circle, with the spatial separation between adjacent towers held constant at 66 cm. The percentage of novel choices declined as 8 towers became 16 and again as 16 towers became 24 but did not decline further. These data were discussed in terms of the fundamental problems posed by variations in the number of food locations in the pursuit of the limit of spatial memory in rats. 相似文献
10.
In two experiments, we examined how the introduction of vertical or horizontal irregularities in the perfectly regular shape of a radial maze affected rats’ performances. The introduction of various tilts in each arm of an eight-arm radial maze had a slightly positive effect on accuracy. However, when intra- and extraraaze cues were dissociated by rotating the maze before maze completion, the rata relied preferentially on extramaze cues associated with the horizontal direction of the arms but not with the tilts. On the other hand, the rats showed poor performances when trained on a horizontally distorted maze (uneven angles between the arms instead of repeated 45° angles). The high number of errors was related to the neglect of particular arms, the disorganization of the patrolling sequences, and the tendency to chain the visit of five arms that formed a regular ahape. Other animals, trained in the same maze, displayed similar biases even after a pretraining phase with constrained choices. Results from the horizontally distorted maze confirm and extend data from the spontaneous alternation literature that choice behavior is influenced by rules of movement that favor large angle transitions and regular subdivisions of space. They also stress the relation between performance in the radial maze and spontaneous exploratory and foraging behaviors. 相似文献
11.
Rats (n=4) searched for food on an eight-arm radial maze. Daily 56-min sessions were divided into eight 7-min time zones, during
each of which a different location provided food; locations were randomized across subjects before training. The rats obtained
multiple pellets within each time zone by leaving and returning to the correct location. Evidence that the rats had knowledge
about the temporal and spatial features of the task includes the following. The rats anticipated locations before they became
active and anticipated the end of the currently active locations. The rats discriminated currently active locations from earlier
and forthcoming active locations in the absence of food transition cues. After the rats had left the previously active location,
they visited the next correct location more often than would be expected by chance in the absence of food transition cues.
The rats used handling or opening doors as a cue to visit the first location and timed successive 7-min intervals to get to
subsequent locations. 相似文献
12.
The effects of food reward on rats’ behavior in radial and Dashiell tunnel mazes were examined in two experiments. In the first, with animals at ad-lib body weights, food reward reduced speed of movement at the food locations, but did not affect the patterns of movement in either maze. Exploratory efficiency in the Dashiell maze was unaffected by food reward, and spontaneous patrolling of the radial maze by the nonrewarded animals was comparable to the behavior, reported by others, of rats running for food reward on elevated eight-arm mazes. In the second experiment, with subjects maintained at 80% of ad-lib body weights, there was some evidence for “winstay” learning: food-rewarded rats in the Dashiell maze were relatively more active near the food locations than were the nonrewarded animals, and more rewarded than nonrewarded rats revisited all food locations in the radial maze. Nonetheless, exploratory efficiency in the Dashiell maze was unaffected by food reward, as was patrolling efficiency in the radial maze, which was again comparable to that of rats on elevated mazes. The similarity in behavior of rewarded and nonrewarded animals in these mazes implies that the major determinant of their behavior, whether or not food reward is provided, is a spontaneous tendency to avoid places recently visited. 相似文献
13.
The conditions necessary for producing retroactive interference (RI) were examined in a 12-arm radial maze. Rats were first given either three or nine forced choices in a to-be-remembered maze. During a 2-h delay, they received one or two trials in a second 12-arm maze, located either in a different room or the same room as the to-be-remembered maze. During the postdelay memory test, RI from the interference trials was produced only when nine choices had been made in the to-be-remembered maze and two interference trials had been conducted during the delay interval. RI was not found when only three forced choices had to be retained or after a single interference trial. The similarity between the interpolated and to-be-remembered mazes had no effect on choice accuracy. It was concluded that two conditions are required for the production of RI in the radial maze. First, a “large amount” of information should be resident in working memory. Second, a substantial number of interpolated trials or choices must be made during the delay. 相似文献
14.
Although pigeons seem to require special training before they will display accurate spatial working memory in radial-arm mazes, they readily show accurate working memory for recently visited feeder locations in an open-field analog of the radial maze. In this task, pigeons forage among sites located on the floor of an open room, with no constraints on the path they take between sites. Experiment 1 suggested that pigeons’ working memory for recently visited sites is facilitated if they are permitted to develop a stable reference memory “map” of the location of the sites with respect to landmarks in the room: Pigeons for which the landmarks remained constant from day to day displayed more accurate working memory than did pigeons for which the landmarks were rearranged between daily trials. The second experiment investigated the durability of pigeons’ working memory, using a forced-choice procedure. Accuracy remained high for retention intervals of up to 32 min, but dropped significantly with a 2-h delay. 相似文献
15.
Marcia L. Spetch 《Learning & behavior》1990,18(3):332-340
In Experiments 1 and 2, pigeons’ spatial working memory in an open-field setting was examined under conditions that differed in terms of working-memory load (number of sites visited prior to a retention test) at various delays between initial choices and the retention test. In Experiment 1, pigeons were tested under two conditions of memory load (three or five sites visited prior to the delay) and two delay intervals (15 and 60 min). Accuracy declined as a function of delay but was not affected significantly by memory load. In Experiment 2A, pigeons were tested under three conditions of memory load (two, four, or six sites visited prior to the delay). In separate phases, the delay was 2, 15, and 60 min. Accuracy was not affected by memory load in any of these phases. In Experiment 2B, three conditions of memory load (two, four, or six sites visited prior to the delay) were tested at two delays (2 and 60 min) within a test phase. Accuracy declined with increasing delay, but memory load again had no significant effects. These results are inconsistent with previous suggestions that pigeons’ retention of spatial information may decline as working-memory load is increased. In Experiment 3, cue-manipulation tests confirmed that pigeons’ choice behavior in the open-field task is controlled by memory for previously visitad room locations. 相似文献
16.
John D. Batson Michael R. Best Deborah L. Phillips Hemlata Patel Kevin R. Gilleland 《Learning & behavior》1986,14(3):241-248
Thirsty rats were trained to collect small water rewards from the end of each arm of an eight-arm radial maze. During these training trials and subsequent testing trials, the subjects were allowed to choose a maximum of eight arms. “Preference” for a target maze location was studied by noting when, in the sequence of eight choices, the target was selected. During testing, when one maze location was consistently devoid of water, rats decreased their preference for this arm over trials (Experiment 1). Similarly, rats that learned a saccharin-lithium association demonstrated lower preferences for a maze location that consistently held the conditioned saccharin solution. This was true for animals that received saccharin-lithium conditioning on the maze (Experiment 3A) and for animals conditioned to saccharin in a separate context (Experiment 3B). An increase in preference for a target maze location consistently containing a sweet chocolate milk solution was observed in animals that were water- and food-deprived (Experiment 2). These studies demonstrate that animals will modify their responses toward (preferences for) maze locations that predictably contain an altered reward. 相似文献
17.
Brown MF Knight-Green MB Lorek EJ Packard C Shallcross WL Wifall T Price T Schumann E 《Learning & behavior》2008,36(4):327-340
In two experiments using a radial-arm maze, pairs of rats made choices among eight maze locations, each containing a large
quantity of one of two food types. The choices made by 1 rat affected the choices made by the other rat. Under most conditions,
visits by 1 rat increased the tendency of the other rat to subsequently choose that maze location. However, the effect depended
on the quality of the food available in a particular location. When it was possible for the rats to observe each other on
the maze arms and a rat had experienced that a location contained the less preferred food type, a previous visit to that location
by the foraging partner decreased the tendency to visit that location. These effects are attributed to working memory for
the spatial choices of another rat, and they indicate that memory produced by a rat’s own visit to a maze location is integrated
with memory for the behavior of another rat to determine spatial choice 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 a standard 12-arm radial maze task. Following training, each trial consisted of a sequence of 2, 4, 6, 8, or 10 choices, followed by a 15-min delay, which then was followed by a choice between a single arm and a response manipulandum mounted in the center of the maze. An arm visit was reinforced if the arm had not been visited prior to the delay, whereas a manipulandum response was reinforced if the arm had been visited. It was found that rats are relatively more likely to reject arms by responding to the manipulandum following a delay occurring late in the choice sequence. This indicates that the choice criterion used by rats in the radial maze becomes more strict as the choice sequence progresses. Such a process provides an alternative explanation for some of the data recently reported by Cook, Brown, and Riley (1985). 相似文献
20.
Rats on an eight-arm radial maze chose between four arms on which a small reward could be obtained after a short delay and
four arms on which a larger reward could be obtained after a longer delay. Experiments 1 and 2 showed that rats preferred
the long-delay, large-reward arms over the short-delay, small-reward arms. This preference was particularly marked when the
arms were made into enclosed alleys. Experiment 3 showed that this effect was not produced by a preference for staying in
enclosed alleys. We argue that the rats endured longer delays to obtain larger rewards when fear of predation was minimized. 相似文献