Memory for spatial and local cues: A comparison of a storing and a nonstoring species

Two passerine species, black-capped chickadees (Parus atricapillus, a food-storing bird) and darkeyed juncos (Junco hyemalis, a nonstoring bird) were compared in a task in which they inspected four feeders in an aviary. Different feeders and different spatial locations were used on each trial. One of the feeders was baited. The subjects returned after a 5-min retention interval to find the baited feeder. Tests with transformations of the feeder array made it possible to determine what cues controlled the food-finding behavior. Chickadees responded to spatial cues preferentially over local color and pattern cues associated with the feeder (Experiments 2–4). The same ordering of responding was found in Experiment 1, a food-storing version of the food-finding task outlined above. Experiment 5 tested juncos on the food-finding task. Juncos responded to all types of information equally. The results are discussed in relation to the notion that because of their food-storing lifestyle, chickadees may need to rely more heavily on spatial cues than do juncos.     

Effects of sucrose concentrations on single-alternation performance in rats

In Experiment 1, rats received single-alternation training with 32% or 4% sucrose reward (Phase 1) followed by a shift in reward from 32% to 4%, and vice versa (Phase 2). In Phase 1, high reward facilitated alternation performance over low reward. In Phase 2, performance on rewarded trials increased as reward increased but was unchanged as reward decreased. Performance on nonrewarded trials showed negligible effects of shifts in reward. In Experiment 2, rats received goalbox placements with 32% or 4% sucrose alternated with nonreward in Phase 1; and in Phase 2, they received alternation runway training with the same or the opposite reward from that of placements. Performance on rewarded trials was faster, the higher the reward in runway training; performance on nonrewarded trials was slower, the higher the reward in placements. In Experiment 3, Phase 1 provided placements with 64%, 32%, 16%, or 4% sucrose or dry mash alternated with nonreward; Phase 2 provided alternation runway training with dry mash reward. Alternation prerformance developed more rapidly, the higher the sucrose concentration in placements. Only 64% sucrose produced performance superior to that for dry-mash placements.     

Interference in pigeons’ long-term memory viewed as a retrieval problem

In Experiment 1, three (experimental) groups of pigeons (n=8) acquired a successive wavelength discrimination in Phase 1 and a reversal in Phase 2; then, after a 24-h delay, they received a wavelength generalization test in extinction (Phase 3). For one group (“Context Same”), the same context was present throughout; for both others, a different context was used for Phase 1 and Phase 2. One group received the generalization test in the presence of Context 1, the other in Context 2. The Context Same and Context 2 experimental groups showed “recency,” with all gradients peaking at the reversal S+ value. The Context 1 group yielded several different response patterns but never showed recency, thus revealing context-generated proactive interference. In Experiment 2, eight subjects learned the original discrimination and its reversal in different contexts, and each bird was tested alternately (within a session) in both contexts. Under this condition, the test contexts were effective retrieval cues. In every case, the gradients obtained in each context peaked sharply at the appropriate S+ value. These experiments indicate that conflicting memories may be stored along with their associated contexts such that they can be retrieved by an appropriate manipulation of contextual cues at the time of retention testing.     

Are there constraints on learned responses to odors from rewarded and nonrewarded rats?

This study determined if test rats could utilize biological odors, generated from donor rats receiving reward (R) and frustrative nonreward (N) treatments, to predict reward and nonreward goal events equally well. In Phase 1, two groups of test rats were exposed to R and N odors that signaled, respectively, either R and N goal events (“same” condition) or N and R goal events (“opposite” condition). Rats demonstrated significant discriminative use of these odors under both conditions. Subjects in the “opposite” condition, however, were slightly slower to learn the discrimination. Reversal learning was readily accomplished in Phase 2, regardless of the same-opposite factor. Thus, little evidence for a constraint on learning was found, and an interpretation in terms of interfering response tendencies and their habituation seemed favored.     

A nonverbal false belief task: the performance of children and great apes

A nonverbal task of false belief understanding was given to 4- and 5-year-old children (N = 28) and to two species of great ape: chimpanzees and orangutans (N = 7). The task was embedded in a series of finding games in which an adult (the hider) hid a reward in one of two identical containers, and another adult (the communicator) observed the hiding process and attempted to help the participant by placing a marker on the container that she believed to hold the reward. An initial series of control trials ensured that participants were able to use the marker to locate the reward, follow the reward in both visible and invisible displacements, and ignore the marker when they knew it to be incorrect. In the crucial false belief trials, the communicator watched the hiding process and then left the area, at which time the hider switched the locations of the containers. When the communicator returned, she marked the container at the location where she had seen the reward hidden, which was incorrect. The hider then gave the subject the opportunity to find the sticker. Successful performance required participants to reason as follows: the communicator placed the marker where she saw the reward hidden; the container that was at that location is now at the other location; so the reward is at the other location. Children were also given a verbal false belief task in the context of this same hiding game. The two main results of the study were: (1) children's performance on the verbal and nonverbal false belief tasks were highly correlated (and both fit very closely with age norms from previous studies), and (2) no ape succeeded in the nonverbal false belief task even though they succeeded in all of the control trials indicating mastery of the general task demands.     

An analysis of serial pattern learning by rats

When rats receive a sequence of rewards of different magnitudes for traversing a runway, they learn to “track” the sequence, showing anticipation of the forthcoming reward by appropriate running speed. There is disagreement as to whether this behavior depends on rats’ encoding and recalling a complete sequence of foregoing hedonic events or just the immediately preceding one. The present experiments showed that rats can remember more hedonic events than the most recent one. In Experiment 1, when exposed concurrently to the sequences 10-1-0 (pellets) and 0-1-10, they were faster on Run 3 of the increasing than of the decreasing sequence, a discrimination which cannot be made on the basis of the preceding (1-pellet) reward alone. Experiment 2 showed that this behavior reflects genuine anticipation of the Run 3 reward, not simultaneous contrast or other simple aftereffects of Runs 1 and 2. It is argued, however, that these results, together with related findings by Capaldi and Verry (1981), show merely that rats can recall a hedonic event other than the most recent one, not that a sequence of such events is fully recalled in order.     

Contrasting Social and Cognitive Accounts on Overimitation: The Role of Causal Transparency and Prior Experiences

Three experiments (N = 100) examine the influence of causal information on overimitation. In Experiment 1, a transparent reward location reveals that the reward is unaffected by nonfunctional actions. When 5‐year‐olds observe an inefficient and subsequently an efficient strategy to retrieve a reward, they show overimitation in both phases—even though the reward is visible. In Experiment 2, children observe first the efficient then the inefficient strategy. The latter is always demonstrated communicatively, whereas the efficient strategy is presented communicatively (2a) or noncommunicatively (2b). Regardless of whether the efficient strategy is emphasized through communication or not, most children do not switch from the efficient to the inefficient strategy. Depending on the situation, children base their behavior on social motivations or causal information.     

Short-term spatial memory in honeybees

Foraging honeybees were trained individually in two-choice spatial problems. Differentially rewarded for spatial alternation in Experiment 1 (“win-shift” training), they showed instead a clear tendency to perseverate—that is, to prefer on each trial the location of reward on the immediately preceding trial. On the basis of the results of Experiments 2 and 3, in which one location was rewarded over shorter or longer series of consecutive trials, an associative interpretation of the perseveration found in the first experiment was rejected in favor of an interpretation in terms of short-term spatial memory. Experiment 4, in which the animals were rewarded on each trial for choosing either location, also showed perseveration. Honeybees, like rats, seem to remember a rewarded location recently visited, but tend to return to it rather than, like rats, to avoid it.     

Search behavior of dogs (Canis familiaris) in invisible displacement problems

Gagnon and Doré (1992) showed that domestic dogs are able to solve a Piagetian object permanence task called the invisible displacement problem. A toy is hidden in a container which is moved behind a screen where the toy is removed and left. Dogs make more errors in these problems than they do in visible displacement tests, in which the object is hidden directly behind the target screen. In Experiment 1, we examined components of the standard procedure of invisible displacements that may make encoding or retention of the hiding location more difficult than it is in visible displacements. In Experiment 2, we compared dogs’ performances in visible and invisible displacement problems when delays of 0, 10, and 20 sec were introduced between the object’s final disappearance and the subject’s release. The results revealed that dogs’ poorer performance in invisible displacement tests is related to the complex sequence of events that have to be encoded or remembered as well as to a difficulty in representing the position change that is signaled, but not directly perceived.     

Strategies used by teachers to rate student behavior

Upon completing the Teacher Report Form (TRF; Achenbach, 1991) on a randomly selected child in their current classroom, teachers were surveyed about the approaches or strategies they used to formulate their ratings. In Phase 1, teachers identified eight rating strategies. In Phase 2, a new group of teachers indicated the extent to which they relied on the eight strategies. Rather than the two approaches hypothesized to be foremost, (“I compared the child to other children in the same classroom,” “I compared the child to other children of the same age”), teachers relied primarily on their “experience with the child in many different settings.” © 2002 John Wiley & Sons, Inc.     

The Initial Impact of the Anatomical Society Gross Anatomy Core Syllabus for Medicine in the United Kingdom: Student and Teacher Perspectives

“What do students studying medicine need to know” is an important question for curriculum planners, anatomy educators and students. The Core Regional Anatomy Syllabus (CRAS), published by the Anatomical Society in 2016, contains 156 learning outcomes (LOs) and has informed “what needs to be known.” This project explored how CRAS had impacted undergraduate anatomy and anatomists in the United Kingdom. A cross-sectional study was designed in two phases. Phase 1, involved a survey of students in clinical years (N = 164). Phase 2 included a survey of anatomist’s views (n = 50) and focus groups of anatomy educators (N = 16). The students’ perspective showed that specific regions of CRAS are deemed less relevant. These were also the body areas where students perceived their anatomical knowledge to be more deficient. Only 46% (n = 75) of students estimated that they knew over 50% (n = 78) of the LOs. Phase two revealed that all anatomists were aware of the syllabus and 48% (n = 24) had checked the CRAS against their own institutional LOs. Anatomists had shared CRAS with colleagues 64% (n = 32) and students at 34% (n = 17), respectively. Forty-six percent (n = 23) of anatomists reported having changed their teaching in some way because of CRAS. The focus groups generated four key themes: “support for CRAS,” “standardization and validation,” “professional identity,” and “limitations and leverage.” Overall CRAS has been well received and is establishing itself within the anatomical community as the new standard for anatomy teaching for medical students.     

Oddity learning in the pigeon: Effect of negative instances,correction, and number of incorrect alternatives

Pigeons have difficulty learning a standard oddity task involving two colors and three stimulus positions. In Experiment 1, performance on standard noncorrection trials was compared with performance on (1) rerun correction trials in which errors resulted in trial repetition, (2) noncorrection trials with added “negative instance” trials involving presentation of three stimuli, all of which matched, and (3) a combination of correction and added negative instance trials. Results indicated that negative instances, but not correction trials, significantly facilitated oddity performance. In Experiment 2, Phase 1, number of stimulus positions lit (three or five) was factorially manipulated with number of positions on which the odd stimulus could appear (three or five). An increase in number of positions lit, but not number of positions that could be odd, facilitated performance. In Phase 2, birds transferred from trials with five positions lit to four positions lit performed significantly better than controls; but in Phase 3, the same birds did not perform significantly better than controls when transferred to trials with three positions lit. In both experiments, analysis of performance as a function of response position indicated better performance at the end of each display than in the middle. These results, together with the group performance differences in Experiment 2, suggest that oddity learning in pigeons involves a size, or number, discrimination.     

Shortcut ability in hamsters (Mesocricetus auratus): The role of environmental and kinesthetic information

Shortcut ability in hamsters was tested in a complex wheel-shaped maze, in which kinesthetic information could be associated with environmental (proximal and/or distal) cues. The hamsters, previously trained to reach a hidden goal by a circumferential route, were led to the center of the maze to test their ability to take a directional shortcut to that same goal. In Experiment 1, their ability to accurately take a straight-line shortcut to the goal (from among eight possible paths) when distal cues were available was demonstrated. In Experiment 2, environmental information was neutralized in some conditions in order to enhance the relevance of kinesthetic information. When circumferential training runs were not too complex, the hamsters could use kinesthetic information—“path integration” processes—integrated during their previous training to infer the direction of the hidden goal.     

Defensive behavior of the rat in a shock-prod situation: Effects of the subject’s location preference

Experiment 1 investigated the proposition that rats cover the source of aversive stimulation with the bedding material available to them and sought to determine whether familiarization with this material would affect burying. The results indicated that rats are no more likely to cover an aversive object than they are not to cover it, although they collect a considerable amount of bedding material in the area surrounding the aversive object. Experiment 2 demonstrated that the rat’s defensive “burying” toward an aversive object is affected by the subject’s predisposition to displace material toward the front side of the apparatus. Some theoretical complexities involved in considering the act of “burying” toward an aversive object as a defensive behavior are discussed.     

Temporal integration in Pavlovian appetitive conditioning in rats

We used an appetitive sensory preconditioning procedure to investigate temporal integration in rats in two experiments. In Phase 1, rats were presented with simultaneous compound trials on which a 10-sec conditioned stimulus (CS) X was embedded within a 60-sec CS A. In Group Early, CS X occurred during the early portion of CS A, whereas in Group Late, CS X occurred during the latter portion of CS A. In Phase 2, CS X was paired simultaneously with sucrose. On a subsequent test with CS A, the rate of magazine entries peaked during the early portions of the stimulus in Group Early and during the latter portions of the stimulus in Group Late (Experiments 1 and 2). Similar response peaks were not observed on tests with a control stimulus that had been presented in compound with a stimulus that did not signal reward (Experiment 2).     

Characteristics of pigeons’ spatial working memory in an open-field task

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.     

Discriminating between reward-produced memories: Effects of differences in reward magnitude

The greater the dissimilarity between exteroceptive stimuli, the easier it is to discriminate between them. To determine whether a similar relationship holds for memories produced by reward events, rats in three runway investigations received trials in pairs, the number of food pellets (0.045 g) occurring on Trial 1 indicating whether reward or nonreward would occur on Trial 2. In each investigation, discriminative responding on Trial 2 was better the larger the difference in reward magnitude on Trial 1. This finding was obtained under a wide variety of conditions: for example, when the larger of two reward magnitudes on Trial 1 signaled nonreward on Trial 2 (Experiment 1, 10 vs. 2 pellets); when the smaller of two reward magnitudes on Trial 1 signaled nonreward on Trial 2 (Experiment 2, 10 vs. 2 pellets); and when the same magnitude of reward on Trial 1 signaled nonreward on Trial 2 (Experiment 3, either 5 pellets or 0 pellets). The findings obtained here indicate that the greater the dissimilarity between reward magnitudes, the greater the dissimilarity between the memories they produced and, thus, the easier it is to discriminate between them. It is suggested that the present results may provide a basis for understanding findings obtained in other instrumental learning investigations in which reward magnitude is varied.     

Not Read,but Nevertheless Solved? Three Experiments on PIRLS Multiple Choice Reading Comprehension Test Items

Multiple-choice (MC) reading comprehension test items comprise three components: text passage, questions about the text, and MC answers. The construct validity of this format has been repeatedly criticized. In three between-subjects experiments, fourth graders (N ₁ = 230, N ₂ = 340, N ₃ = 194) worked on three versions of MC items from the Progress in International Reading Literacy Study 2001 reading comprehension test with relevant components successively deleted: “original version” (text, questions, MC-answers), “version without text” (questions, MC-answers), “version without text and without questions” (only MC-answers). Answering correctly the MC items became more difficult as the relevant information was eliminated. In the two narrative fictional texts presented, the students' performance of the version without text was not better than chance. Conversely in the informational (fictional) text, the students' performance of the version without text was better than chance. In the third condition, students' performance was never better than chance.     

也谈Cabbages and Kings的汉译问题

文章从翻译功能论视角对欧·亨利英文短篇小说集名Cabbages and Kings 的两种译文进行解读。译文《白菜与皇帝》一定程度上影响了交际功能的实现,却完成了文化传递的功能。《东拉西扯》实现了翻译交际功能,却牺牲了文化传递的功能。因此,两种译文各有得失,无对错之别。另外,随着东西方文化交流逐渐加强,译文《白菜与皇帝》必将被越来越多的读者接受。     

Correction to: Initial judgment of solvability in non-verbal problems – a predictor of solving processes

Metacognition and Learning - The original version of this article unfortunately contained a mistake in page 7, particularly in the second paragraph of “Procedure” section of Experiment...