Pigeons’ spatial memory: V. Proactive interference in the delayed matching of key location paradigm occurs only under restricted conditions

In the delayed matching of key location procedure, pigeons must remember the location of the sample key in order to choose correctly between two comparison keys. The deleterious effect of short intertrial intervals on key location matching found in previous studies suggested that pigeons’ short-term spatial memory is affected by proactive interference. However, because a reward expectancy mechanism may account for the intertriai interval effect, additional research aimed at demonstrating proactive interference was warranted. In Experiment 1, matching accuracy did not decline from early to late trials within a session, a finding inconsistent with a proactive interference effect. In Experiment 2, evidence suggestive of proactive interference was found: Matching was more accurate when the locations that served as distractors and as samples were chosen from different sets. However, this effect could have been due to differences in task difficulty, and the results of the two subsequent experiments provided no evidence of proactive interference. In Experiment 3, the distractor on Trialn was either the location that had served as the sample on Trialn ? 1 or one that had been a sample on earlier trials. Matching accuracy was not inferior on the former type of trial. In Experiment 4, the stimuli that served as samples and distractors were taken from sets containing 2, 3, 5, or 9 locations. Matching accuracy was no worse, actually slightly better, with smaller memory set sizes. Overall, these findings suggested that pigeons’ memory for spatial location may be immune to proactive interference. However, when, in Experiment 5, an intratrial manipulation was used, clear evidence of proactive interference was found: Matching accuracy was considerably lower when the sample was preceded by the distractor for that trial than when it was preceded by the sample or by nothing. Possible reasons why interference was produced by intratrial but not intertrial manipulations are discussed, as are implications of these data for models of pigeons’ short-term spatial memory.     

Automatic conceptual encoding of printed verbal material: Assessment of population differences

The release from proactive interference task was used to investigate categorical encoding of animal and clothing items with fourth grade low-socioeconomic status black and middle-socioeconomic status white children. The print mode of verbal presentation and an ordered recall requirement were used in order to provide hospitable conditions for the detection of population differences. The results indicated parity in buildup and release from proactive interference for the two populations. The results of this study, consistent with previous estimates of release from proactive interference for these groups (e.g., D. W. Kee & L. Helfend, Journal of Educational Psychology, 1977, 69, 344–348; S. Y. Nakayama & D. W. Kee, Journal of Educational Psychology, 1980, 72, 386–393), indicate that low-socioeconomic status black and middle-socioeconomic white children do not differ in automatic conceptual encoding. Conceptual encoding differences, however, have been detected between these populations when the free recall method has been used. Thus, discussion of the present results includes a consideration of factors which may be responsible for population differences in free recall performance and preliminary evidence on this issue is provided.     

Overconfidence produces underachievement: Inaccurate self evaluations undermine students’ learning and retention

The function of accurately monitoring one’s own learning is to support effective control of study that enhances learning. Although this link between monitoring accuracy and learning is intuitively plausible and is assumed by general theories of self-regulated learning, it has not received a great deal of empirical scrutiny and no study to date has examined the link between monitoring accuracy and longer-term retention. Across two studies, college students paced their study of key-term definitions (e.g., “Proactive interference: Information already stored in memory interferes with the learning of new information”). After all definitions were studied, participants completed practice cued recall tests (e.g., “What is proactive interference?”) in which they attempted to type the correct definition for each term. After each test trial, participants judged how much of their response was correct. These study-test-judgment trials continued until a definition was judged as correct three times. A final cued recall test occurred two days later. In Study 1, judgment accuracy was manipulated experimentally, and in Study 2, individual differences in accuracy were examined. In both studies, greater accuracy was associated with higher levels of retention, and this link could not be explained by differential feedback, effort during study, or trials to criterion. Results indicate that many students could benefit from interventions aimed at improving their skill at judging their learning.     

Visual environment and delay affect cache retrieval accuracy in a food-storing rodent

Many scatter-hoarding species use spatial memory to relocate their food caches. Two factors can affect spatial memory: the availability of landmarks in the environment, and the latency between learning and recall. Using a 2 × 2 factorial design, we determined the effect of these factors on cache retrieval accuracy in Merriam’s kangaroo rats (Dipodomys merriami). Kangaroo rats cached seeds in an arena under conditions that varied by retrieval interval (1 or 10 days) and by number of landmarks (0 or 16 landmarks). After 1 day, they recovered equal proportions of caches in both landmark conditions. After 10 days, they recovered more caches in the 16-landmark condition than in the bare condition. This is the first study to show that landmarks are necessary for accurate cache recovery after long delays. This result is consistent with maze studies that have shown that landmarks reduce proactive interference and that delay increases proactive interference.     

Parameters of remembering and forgetting in the transition from infancy to early childhood

The ability to recall is something that most intact adults take for granted. For much of the last century, this feature of mental life was not considered to extend to very young children. There now is evidence that 1- to 2-year-olds are able to recall specific events after delays of several months. Over the short term, 1- to 2-year-olds' recall is affected by the same factors that affect older children's recall; it is not clear whether similar effects are apparent over the long term. Moreover, although age-related increases in long-term recall are assumed, there have been few empirical tests of the question. We examined recall by 14- to 32-month-olds for events experienced at 13 to 20 months. Using elicited imitation of novel multistep event sequences we examined effects of (a) delay length, (b) age at the time of experience, (c) temporal structure of events, (d) mode of experience of events, and (e) availability of verbal reminders, on long-term recall. Participants were 360 children enrolled at 13 (n = 90), 16 (n = 180), and 20 (n = 90) months. All of the 13-month-olds and half of the 16-month-olds were tested on 3-step event sequences; all of the 20-month-olds and half of the 16-month-olds were tested on 4-step event sequences. Within each age and step-length group, equal numbers of children were tested after intervals of 1, 3, 6, 9, and 12 months (n = 18 per cell). Children were tested on a variety of sequence types. For half of the events, imitation was permitted prior to the delay; for the other half, children were not permitted imitation. At delayed testing, children experienced a recall period during which they were cued by the event-related props alone, followed by a period in which recall was cued both by the event-related props and by verbal labels for the event sequences. Within step-length groups, the length of time for which older and younger children showed evidence of memory did not differ. Nevertheless, when the children were prompted by the event-related props alone, there were age-related differences in the robustness of children's memories (as indexed by higher levels of recall for older children relative to younger children). When the children were prompted by the props and by verbal labels for the event sequences, at the longer retention intervals, there were age-related differences in the robustness of children's memories and in the reliability with which recall was evidenced (as indexed by the larger numbers of older children evincing recall). Age-related effects were particularly apparent on children's ordered recall. Across the entire age range, the children were similarly affected by the variables of sequence type, opportunity for imitation, and verbal reminding.     

Directed forgetting among third and seventh graders

The present studies examined the effectiveness of explicit and implicit Forget cues for enhancing memory of to-be-remembered items within a directed forgetting paradigm. Such a paradigm may be viewed as a laboratory analogue to a classroom testing situation where students read through an examination before beginning in order to cue themselves as to which information is important to remember. Subjects were third- and seventh-grade children. Evidence was provided that directed forgetting processes were operative at the time of recall so that memory enhancement did not merely reflect differential rehearsal of the to-be-remembered items during study. When easy partitioning of items into Remember and Forget sets was possible, subjects as young as third graders could benefit from postpresentation Forget cues. The data suggest that postpresentation Forget cues permit a selective search during recall and a consequent reduction in interference from to-be-forgotten items. Applications of these findings to a classroom testing situation were discussed.     

Do, Show, and Tell: Children's Event Memories Acquired through Direct Experience, Observation, and Stories

To investigate how source of event information influences children's event representations, 5- and 6-year-old children were exposed to a novel event through direct experience, observation, or a story. 2 of the 4 scenes comprising the event contained actions that were logically organized, and the remaining 2 scenes contained actions that were arbitrary in their organization. Children received either 1 or 3 exposures to the event. For children receiving multiple exposures, 2 scenes contained actions that varied across exposures. A few days following their last exposure, children were asked to verbally recall and reenact the event. Reports were generally more complete, organized, and accurate when the event was directly experienced compared to when it was observed or heard about through a story. However, the impact of information source interacted with interview (recall, reenactment) and number of event exposures. Furthermore, children's sensitivity to event structure was dependent on information source and exposure. These results highlight the importance of information source in the formation of children's event representations.     

Explanation and generalization in young children's strategy learning

Children often learn new problem-solving strategies by observing examples of other people's problem-solving. When children learn a new strategy through observation and also explain the new strategy to themselves, they generalize the strategy more widely than children who learn a new strategy but do not explain. We tested three hypothesized mechanisms through which explanations might facilitate strategy generalization: more accurate recall of the new strategy's procedures; increased selection of the new strategy over competing strategies; or more effective management of the new strategy's goal structure. Findings supported the third mechanism: Explanations facilitated generalization through the creation of novel goal structures that enabled children to persist in use of the new strategy despite potential interference from competing strategies. The facilitative effect of explanation did vary with children's age and did not vary between explanations children created by themselves versus explanations they learned from the experimenter.     

Like Father, Like Son: Young Children's Understanding of How and Why Offspring Resemble Their Parents

4 studies investigated the broad claim that preschoolers understand biological inheritance. In Study 1, 4–7-year-old children were told a story in which a boy was born to one man and adopted by another. The biological father was described as having one set of features (e.g., green eyes) and the adoptive father as having another (e.g., brown eyes). Subjects were asked which man the boy would resemble when he grew up. Preschoolers showed little understanding that selective chains of processes mediate resemblance to parents. It was not until age 7 that children substantially associated the boy with his biological father on physical features and his adoptive father on beliefs. That is, it was not until age 7 that children demonstrated that they understood birth as part of a process selectively mediating the acquisition of physical traits and learning or nurturance as mediating the acquisition of beliefs. In Study 2, subjects were asked whether, as a boy grew up, various of his features could change. Children generally shared our adult intuitions, indicating that their failure in Study 1 was not due to their having a different sense of what features can change. Studies 3 and 4 replicated Study 1, with stories involving mothers instead of fathers and with lessened task demands. Taken together, the results of the 4 studies refute the claim that preschoolers understand biological inheritance. The findings are discussed in terms of whether children understand biology as an autonomous cognitive domain.     

Role of proactive interference in infantile forgetting

Ontogenetic changes in the role of proactive interference in augmenting forgetting were tested with 444 rats as subjects. In Experiment 1, Phase 1 (the source of proactive interference) included events that were contingent or not contingent on responding in the context of either the Phase 2 training apparatus or a distinctly different apparatus. After learning a spatial discrimination for Phase 2, retention tests were given after intervals of 2 min, 1 day, 7 days, 30 days, or 65 days. The results indicated: (1) infantile amnesia, and (2) proactive interference for infant rats but not for adults, in spite of substantial simple forgetting among adults. Experiment 2 extended the test to a go/no-go avoidance task. The results of Experiment 2 gave some indication that infants were more susceptible than were adults to proactive interference over short intervals, but the generality of this relationship was sufficiently ambiguous as to suggest different mechanisms of interference for the discrimination and go/no-go tasks. These data indicate multiple mechanisms of infantile forgetting that may vary with certain characteristics of the task.     

Children's ability to make probability estimates: skills revealed through application of Anderson's functional measurement methodology

Functional measurement methodology was used to assess children's attention to the total number of alternative outcomes as well as the number of target outcomes when making probability estimates. In Study 1, first-, third-, and fifth-grade children were given the task of estimating on a simple, continuous but nonnumeric scale the probability of drawing a particular color of jelly bean from a bag containing either 1, 2, or 3 jelly beans of that color, and either 6, 8, or 10 jelly beans total. In Study 2, first- through fifth-grade children were given the task of estimating the likelihood that a bug would fall on a pot containing a flower when presented displays of planters containing either 2, 3, 4, or 5 pots with flowers, and 6, 8, or 10 pots total. In both studies, the children were exposed to each of the combinations of numerator and denominator across 3 replications. The results indicate that all age groups attend to variations in the denominator as well as to variations in the numerator, and, furthermore, that they attend to the interaction between these variables. This finding contrasts sharply with research that requires children to choose which of 2 containers offers the greater chance of yielding a target item in a blind draw. It is suggested that children possess the skill to make accurate probability estimates, but they are unaware that these estimates should always be made and used when comparing the probability of an event across trials. The findings are discussed in relation to the broader issue of the limitations of the choice paradigm as a means of investigating children's thinking.     

The effect of modality shifts on proactive interference in long-term memory

Two experiments examined the effects of shifts in the modality on proactive interference in long-term memory. In Experiment 1 subjects learned a 40-word list presented in one of two forms of auditory/visual change—blocked or random. In the blocked conditions, learners were presented half the words in one modality followed by the remaining 20 words in the other modality. Subjects in random conditions also received 20 nouns in each modality, but the presentation was random. Following a delay, all subjects completed an 80-item recognition test. Analysis of these data showed a definite effect (p < .001) for the random change in modality when compared to the blocked presentation. As predicted, distinct reduction in serial position effects was found with the modality of presentation was random. In contrast, the blocked presentation produced two well-defined serial position curves. In Experiment 2 the effects of a shift in the modality of presentation on proactive interference were studied with high and low conceptual rigid subjects. Four similar prose passages were presented with a modality shift taking place in the last passage in a shift condition. Subjects in nonshift conditions were presented the passages exclusively in either the auditory or visual mode. The results showed that a shift in the modality of presentation of a prose passage provided a powerful releaser from proactive interference. The superior performance of rigid thinkers regardless of experimental group membership was explained in terms of organizational memory strategies.     

Comparing cognition by integrating concept learning,proactive interference,and list memory

This article describes an approach for training a variety of species to learn the abstract concept of same/different, which in turn forms the basis for testing proactive interference and list memory. The stimulus set for concept-learning training was progressively doubled from 8, 16, 32, 64, 128 . . . to 1,024 different pictures with novel-stimulus transfer following learning. All species fully learned the same/different abstract concept: capuchin and rhesus monkeys learned more readily than pigeons; nutcrackers and magpies were at least equivalent to monkeys and transferred somewhat better following initial training sets. A similar task using the 1,024-picture set plus delays was used to test proactive interference on occasional trials. Pigeons revealed greater interference with 10-s than with 1-s delays, whereas delay time had no effect on rhesus monkeys, suggesting that the monkeys’ interference was event based. This same single-item same/different task was expanded to a 4-item list memory task to test animal list memory. Humans were tested similarly with lists of kaleidoscope pictures. Delays between the list and test were manipulated, resulting in strong initial recency effects (i.e., strong 4th-item memory) at short delays and changing to a strong primacy effect (i.e., strong 1st-item memory) at long delays (pigeons 0-s to 10-s delays; monkeys 0-s to 30-s delays; humans 0-s to 100-s delays). Results and findings are discussed in terms of these species’ cognition and memory comparisons, evolutionary implications, and future directions for testing other species in these synergistically related tasks.     

Children''s Sex-related Stereotyping of Colors

4 studies addressed children's sex-related stereotyping of colors. Study 1 examined preschoolers' awareness of color stereotypes. Children were presented with 6 toy animals, identical except for color, and were asked to identify the sex of each animal and to select a favorite. Both sex identifications and toy preferences were highly consistent with adult color stereotypes. Study 2 demonstrated that clothing color influences preschool, kindergarten, and first-grade children's impressions of other children whose sex is known. Studies 3 and 4 indicated that the effects of stereotyping based on color are modest in comparison to the effects of stereotyping based directly on sex. In addition, color stereotyping did not show the regular age-related increase that is characteristic of sex-role stereotyping.     

Cumulative proactive interference in animal memory

Events occurring on the prior trial in delayed matching-to-sample tasks can proactively interfere with accurate matching on the current trial. The present study investigated the accumulation of proactive interference in delayed matching-to-sample at the local level of two consecutive trials, as well as in terms of a general performance decrement accumulating over the session. Higher-order analyses, in terms of the parameters of negative exponential functions fitted to the data, showed that the magnitude of the local proactive-interference effect resulting from inter-trial disagreement of stimuli decreased over the session. Furthermore, there was no evidence for the general performance decrement over the session, which is frequently attributed to proactive interference. The attenuation of the local proactive-interference effect was accounted for in terms of changes in the relative probabilities of agreeing and nonagreeing trials.     

The mathematical strengths and weaknesses of children with dyslexia

This paper reports the findings of two related studies that examined the mathematical strengths and weaknesses of children with dyslexia. In study one, dyslexic children were compared to children without special educational needs on tests that assessed arithmetic fact recall, place value understanding and counting speed. Study two used the same methodology, but matched the dyslexic children with the non‐dyslexic children on a number of factors, including intellectual ability. This excluded the possibility that confounding variables accounted for the differences between the groups in study one. Both studies indicated that the dyslexic children had slower and less accurate number fact recall than the non‐dyslexic children, but had unimpaired place value understanding. The results for counting speed were more equivocal, but there was a trend for the dyslexic children to be slower counters. The results suggest that dyslexia is not normally associated with a general mathematical impairment, but rather an uneven profile of skills. This profile can be explained in terms of the phonological processing weaknesses associated with dyslexia. The finding that dyslexic children have a specific difficulty recalling arithmetic facts suggests that a teaching programme that emphasises mental methods may disadvantage them.     

Children's eyewitness memory for a repeated event

OBJECTIVE: This study examined a significant issue for chronic sexual abuse investigations: Children's eyewitness testimony about repeated events. The few previous studies focused on preschoolers and none used the present methodology of presenting repeated events differing slightly in their details, as would happen in chronic abuse. METHOD: One group of 6- to 7-year-olds played individually with an experimenter on one occasion; the other group experienced three such events, with some details remaining the same and others changing. In a phased interview, children were questioned about the initial event. RESULTS: For details which stayed the same, the children who experienced three events had more accurate memories. They had poorer memories than the single-event group for details which were changed in the later events; however, this was due to interference errors, with errors of omission and commission being lower than in the single-event group. Children conveyed clearly that inappropriate touching did not occur. CONCLUSIONS: Children who experience repeated events have increased recall for repeated details but confuse the timing of details which change across events. The findings support previous suggestions that (a) it is unrealistic to expect children to be able to report repeated events without some confusion about timing of details and (b) children are resistant to misleading questions about abuse.     

Where Theories of Mind Meet Magic: The Development of Children's Beliefs about Wishing

In two studies, we probed children's beliefs about wishing. In Study 1, we gathered initial data on 50 3- to 6-year-old children's concepts of wishing and beliefs about its efficacy, with both a semistructured interview and a variety of tasks. Results revealed considerable knowledge about wishing in young children, along with an age-related decrease in beliefs about its efficacy. Parents were not found to encourage differently the beliefs of children at different ages, nor were they found to begin actively discouraging such beliefs at any particular age. A moderate relation was found between environmental supports for wishing and children's beliefs in its efficacy. In Study 2, we continued to probe these issues and also address the nature of the broader conceptual context in which children situate their beliefs about wishing. Participants were 92 3- to 6-year-old children. Results of this study suggest that children may reconcile beliefs in the efficacy of wishing with knowledge about everyday mental-physical relations by situating these beliefs more within their emerging beliefs about magic than within their theories of mind.     

Children's suggestibility in relation to their understanding about sources of knowledge

In the experiments reported here, children chose either to maintain their initial belief about an object's identity or to accept the experimenter's contradicting suggestion. Both 3- to 4-year-olds and 4- to 5-year-olds were good at accepting the suggestion only when the experimenter was better informed than they were (implicit source monitoring). They were less accurate at recalling both their own and the experimenter's information access (explicit recall of experience), though they performed well above chance. Children were least accurate at reporting whether their final belief was based on what they were told or on what they experienced directly (explicit source monitoring). Contrasting results emerged when children decided between contradictory suggestions from two differentially informed adults: Three- to 4-year-olds were more accurate at reporting the knowledge source of the adult they believed than at deciding which suggestion was reliable. Decision making in this observation task may require reflective understanding akin to that required for explicit source judgments when the child participates in the task.     

The effects of summary production and encoding condition on children��s metacognitive monitoring

Two studies were conducted to investigate whether context variations were suitable to improve metacognitive judgments in children in a complex, everyday memory task. In the first phase of each experiment, participants were shown a short event (video) and gave judgments-of-learning (JOLs), that is, rated their certainty that they would later be able to recall specific details correctly. In the second phase of the experiments, participants took part in a memory interview about the memory event and gave confidence judgments (CJs), that is, rated their certainty that the provided answers to the memory questions were correct. Study 1 specifically investigated the potential positive influence of giving a verbal summary before the JOL-interview on metacognitive monitoring, whereas Study 2 had a closer look on the effect of intentional versus non-intentional encoding on JOL and CJ accuracy. Results revealed no significant influence of giving a summary and hardly any effect of encoding condition on metamemory monitoring although children from age 6 on showed adequate monitoring performance. JOL accuracy appears to be a complex process, which is even more difficult to influence in children than in adults.