Age-related differences in clustering: A new approach

The present study attempted to determine why children under 8 years of age show categorical clustering in free recall above chance expectations, but such organization does not correlate with recall. Six-year-old children and adults were tested for their memory for 24 pictures of categorizable items. Several new measures of organization such as the proportion of items recalled in category strings and number of strings of each length were evaluated. It was found that children's output is characterized by strings of only two intracategory items and many isolates which does not contribute to recall. Adults produced longer strings from more categories which enhanced recall. In addition, different characteristics of output organization predicted recall for adults and children.     

Quantitative and qualitative aspects of memory for picture stimuli

Children aged approximately 8.5–9.5 years were shown either names (NP), or pictures (PP), of objects, for each of which they located the corresponding likenesses among an array of alternatives. Written recall and identification accuracy were assessed at 5 hr and 3 days after presentation. As predicted, NP produced significantly superior recall to PP. The rate of identification for recalled items among Ss in PP was significantly higher than that for NP. This result was interpreted as supporting the view that the superiority of NP in recall derives from the fact that Ss may rely upon retrieval from either name or image of each item whereas those in PP must depend upon image alone. This interpretation was extended to take two unexpected findings into account: (i) the superior overall identification accuracy engendered by PP, particularly at the longer time interval; (ii) the relatively weak relationship between identification accuracy and recall scores among matching Ss.     

The development of conceptual and rote recall skills among school age children

One hundred eighty children from Grades K, 5, and 9 performed a recall task within one of four instructional conditions: serial recall; standard free recall; labeling free recall; labeling cued recall. The task required that Ss view and recall items from three successively presented sets of categorized pieture stimuli. Controls were imposed upon the associatice relatedness of items within sets so as to minimize the occurrence of associative responding during recall. The clustering data showed that kindergarten and fifth grade children are able to use conceptual skills to effectively mediate recall, but fail to effect these skills on a spontaneous basis in free recall. The results were discussed in line with the hypothesis that young children fail to engage in planful cognitive activity in recall tasks.     

Associative and categorical hypotheses of organization in the free recall of adults and children

Associative and categorical explanations for the organization children and adults display in free recall were tested. It was expected that young children would show output clustering as a function of associations between individual items within categories rather than relationship to the taxonomy itself. Kindergarten, fourth-grade, and tenth-grade subjects were presented with pictures representing the four factorial combinations of high and low interitem association and high and low category relatedness. Each set of pictures could be divided into four taxonomic categories of six items each. Kindergarteners displayed greater category clustering of highly associated items than weak associates. Older subjects showed sensitivity to both organizational dimensions. These data support a hypothesis that young children cluster in recall as a function of associations while older individuals show organizational flexibility which serves to facilitate greater recall.     

Perceptual processing in dichotic listening.

Subjects heard two lists of 4 items each presented simultaneously to the two ears at a rate of four pairs of items per sec. A recall cue presented immediately after the test list signalled report of 4 of the 8 items. In recall by spatial location, the cue indicated whether the items on the right ear on left ear should be recalled. In recall by category name, the cue indicated the superset category (e.g., letters or words) of the items to be recalled. Recall by spatial location was not significantly different than recall by category name. This results argues against the idea of a preperceptual auditory storage that holds information along spatial channels for 1 or 2 sec. The final experiment showed that recall by spatial location is significantly better than recall by category name when the report cue is given before, not after, the list presentation. These results show that spatial location can be used to enhance semantic processing and/or memory of 1 of 2 simultaneous items, but only if the relevant location is known at the time of the item presentation.     

Developmental changes in apportionment of study time among items in a multitrial free recall task

First grade, third grade, and college Ss attempted to memorize a single set of items over the course of 5 trials, each trial consisting of a 45-sec study period followed by a free recall test. On all trials but the first, S was allowed to have available during his study period only half of the total set of items, but was free to select whichever items he wished to include in this half. Third grade and college Ss were significantly more prone than first grade Ss to select for study items not recalled in the immediately preceding recall test. The results suggest that the strategy of deliberately concentrating one's study activities on the less well mastered segments of materials to be learned, like other elementary memory strategies (e.g., rote rehearsal), cannot automatically be assumed to be part of a young child's repertoire of learning techniques.     

Degree of Disturbance in Figure Drawings as Related to Mode of Approach to Problem Solving

Spontaneous and induced hierarchical organization was investigated with 72 first, third, and fifth graders (12 females and 12 males at each grade level). Stimuli consisted of an initial set of 20 unrelated pictures and a second set of 20 pictures which could be classified according to four super ordinate categories. Ss were randomly assigned to either the spontaneous or induced condition for the second set. Both recall scores and clustering indexes indicated that induced organization facilitates recall(p < .01 and p < .05, respectively). The effect of the induced presentation condition was most pronounced for third and fifth graders (p < .05). The clustering analysis indicated sex differences in the induced presentation condition (p < .05); with increasing age, girls exhibited a greater improvement than boys in induced organizational ability.     

The advantages of mathematical modeling over traditional methods in the analysis of category clustering

A mathematical model for the analysis of category clustering is developed and testd. The model, which can be applied to categories of any size, is an extension of a two-item statistical model developed by Batchelder and Riefer (Psychological Review, 1980, 87, 375–397), and is equivalent to their model when categories consist of two items. The model is based on a current theory of clustering which postulates that the learning of a list of category items occurs on different hierarchical levels. Two category list-learning experiments are presented, and the data from these experiments are analyzed using the general statistical model. The first experiment reveals that the probabilities of storing and retrieving a cluster increase with category size, while the learning of items as singletons decreases. The effects of within-category spacing indicate that the storage of clusters decreases while cluster retrievability increases with an increase in input spacing. In the second experiment, the storage and retrieval of clusters are shown to be unaffected by whether the presentation of items is uncued or cued with the name of the category. However, the association of items decreases and the learning of items as singletons increases with uncued presentation. In the final sections, the general statistical model is compared to other methods for the measurement of category clustering. The model is shown to be superior to numerical indices of clustering, since these measures are not based on any theory of clustering, and because unitary measures cannot capture the multiprocess nature of categorized recall. The model is also argued to have certain advantages over other mathematical models that have been applied to category clustering, since these models cannot account for situations in which a portion of the items are clustered while others are learned singularly.     

Effects of context variation, intracategory variation, and spacing on the free recall of pictures

Abstract.— Two experiments examined the effects of encoding variability on the free recall of pictures. In Expt. I, drawn objects were presented 3 times in different pictorial contexts (RV) or in the same contexts (RR). In Expt. II, repeated stimuli were 3 different specimens of the same object category (VR) or the same object presented 3 times (RR). Spacing of repetitions was varied from zero to 15, and a mixed-list design was used. Both RV and VR items tended to be recalled better than and prior to RR items. Recall of RR and of VR items increased with increasing spacing, but recall of RV items showed no spacing effect. In a second recall test, preceded by 4 min of "thinking about" the pictures, the only remaining effect of spacing or of context variation was a low recall of massed RR items. VR items were still recalled better than and prior to RR items. It is suggested that spacing, and variation of the external context of pictures, facilitate retrieval when the time and effort spent on recall is limited, by increasing the numberlvariety of potential recall cues stored together with item information.     

Category typicality effects in children's memory performance: Qualitative and quantitative differences in the processing of category information

Kindergarten, third, and sixth graders (6, 9, and 12 years of age, respectively) received a cue-at-input/cue-at-output recall task, using category typical and atypical items that were based on either (1) children's conceptions of item typicality, or (2) adults' conceptions of item typicality. At each grade level, recall was greater with the child-defined lists than with the adult-defined lists, and typical items were recalled to a greater extent than atypical items. Further analyses items were recalled to a greater extent than atypical items. Further analyses revealed that the recall of typical items varied as a function of children's typicality ratings of items, and that the “typicality effect” in the adult-norm condition was due primarily to the childrennot realizing that many of the atypical items were appropriate category exemplars. In contrast, typicality effects in the child-norm condition were attributed to qualitative differences in the judged “goodness of example” of the typical and atypical items. The results were discussed in terms of the appropriateness of typicality as a dimension of children's natural language concepts, the role of age differences in knowledge base in affecting performance on a cognitive task, and of the importance of using child-generated norms in studies of children's processing of category information.     

Is the picture bizarreness effect a generation effect?

Bizarre stimuli usually facilitate recall compared to common stimuli. This investigation explored the so-called bizarreness effect in free recall by using 80 simple line drawings of common objects (common vs bizarre). 64 subjects participated with 16 subjects in each group. Half of the subjects received learning instructions and the other half rated the bizarreness of each drawing. Moreover, drawings were presented either alone or with the name of the object under mixed-list encoding conditions. After the free recall task, subjects had to make metamemory judgments about how many items of each format they had seen and recalled. The key result was that a superiority of bizarre pictures over common ones was found in all conditions although performance was better when the pictures were presented alone than with their corresponding label. Subsequent metamemory judgments, however, showed that subjects underestimated the number of bizarre items actually recalled.     

Categorical and schematic organization and the development of retrieval strategies

This study investigated the effects of schematic and categorical organization on young children's recall. Preschool and kindergarten children recalled either a taxonomic list or a story in one of two presentation conditions: an alternate condition, in which the material was presented, children recalled it and the procedure was repeated, or a successive condition in which the material was presented twice and children recalled it twice. Although preschool children's story recall was well organized, their list recall was poorly organized, and organization did not increase over recall trials in either presentation condition. In contrast, kindergarten children's recall of both the story and the list was well organized, and their recall was better organized on the second recall trial than on the first in both presentation conditions. These results are discussed in terms of the development of retrieval strategies during the preschool years/     

On the relative and absolute strength of a memory trace

Subjects studied either an 8- or 16-word list and later recalled the items while a voice key recorded each response latency. The trials were partitioned by recall total in order to examine the means and distributions of both latencies and interresponse times as a function of recall total. Each analysis was consistent with the view that an item’s absolute strength determineswhether it is recalled whereas an item’s relative strength determineswhen it is recalled. In addition, mean latency was effectively proportional to study list length yet independent of recall total. All of the analyses were consistent with the view that the set of study items is sampled according to a relative-strength rule until all items are found and that a sampled item is recovered into consciousness only when its absolute strength exceeds a fixed threshold.     

Recall in preschool children

Free recall, cued recall, color recall, organization in recall, and sorting of 3- and 4-year-olds was assessed on 9-item lists of objects that were orthogonally varied on color and category dimensions. Half of the children in each age group were presented items successively, and the other half simultaneously. Older children recalled more items than younger children in both free and cued recall, and also organized their recall more. Moreover, simultaneous presentation benefited the older, but not younger children. Clustering and sorting data suggested a decreasing reliance on perceptual information, and increasing utilization of conceptual information, over the preschool years. The results were discussed in terms of the importance of concrete, external stimulus support at both time of encoding and retrieval.     

Strong items get suppressed, weak items do not: The role of item strength in output interference

An experiment is reported that examines the role of item strength in output interference. Subjects studied two types of categorized item lists: lists in which each category consisted of strong and moderate items, and lists in which each category consisted of weak and moderate items. Different degrees of item strength were accomplished by varying the items’ taxonomic frequency within a category. The subjects either recalled a category’s strong and weak items before its moderate items, or vice versa. The prior recall of the moderate items impaired the later recall of the strong items, but did not impair the later recall of the weak items. This effect of item strength indicates that output interference is caused by a process of retrieval suppression. It additionally suggests that, in order to minimize output-interference effects in recall, a list’s strong items should be recalled before its weak items.     

Pictorial superiority effects in oldest-old people

We examined memory for pictures and words in middle-age (45–59 years), young-old (60–74 years), old-old (75–89 years), and the oldest-old adults (90–97 years) in the Louisiana Healthy Aging Study. Stimulus items were presented and retention was tested in a blocked order where half of the participants studied 16 simple line drawings and the other half studied matching words during acquisition. Free recall and recognition followed. In the next acquisition/test block a new set of items was used where the stimulus format was changed relative to the first block. Results yielded pictorial superiority effects in both retention measures for all age groups. Follow-up analyses of clustering in free recall revealed that a greater number of categories were accessed (which reflects participants’ retrieval plan) and more items were recalled per category (which reflects participants’ encoding strategy) when pictures served as stimuli compared to words. Cognitive status and working memory span were correlated with picture and word recall. Regression analyses confirmed that these individual difference variables accounted for significant age-related variance in recall. These data strongly suggest that the oldest-old can utilise nonverbal memory codes to support long-term retention as effectively as do younger adults.     

Retrieval failure, rehearsal deficiency, and short-term memory loss in the aphasic adult

Studies show that aphasic patients typically are grossly impaired in short-term memory performance. Since aphasics generally experience difficulty in word retrieval, it is conceivable that short-term memory loss is partially the result of verbal rehearsal deficiency which, in turn, is caused by the word retrieval problem. This paper reports an experiment in which five aphasic adults were nonverbally to recall individualized lists of pictures they could easily name and lists of pictures they could not name. Final items in the two lists were recalled with equal accuracy; this was expected in that the recency effect usually reflects sensory rather than verbal storage. Initial items were recalled with greater accuracy than middle-list items in the nameable sets but not in the unnameable sets. This primacy effect suggests the aphasics rehearsed the nameable pictures, but both lists were recalled so poorly that rehearsal deficit was considered responsible for no more than a fraction of the aphasics' reduction in short-term memory.     

Pictorial superiority effects in oldest-old people

We examined memory for pictures and words in middle-age (45-59 years), young-old (60-74 years), old-old (75-89 years), and the oldest-old adults (90-97 years) in the Louisiana Healthy Aging Study. Stimulus items were presented and retention was tested in a blocked order where half of the participants studied 16 simple line drawings and the other half studied matching words during acquisition. Free recall and recognition followed. In the next acquisition/test block a new set of items was used where the stimulus format was changed relative to the first block. Results yielded pictorial superiority effects in both retention measures for all age groups. Follow-up analyses of clustering in free recall revealed that a greater number of categories were accessed (which reflects participants' retrieval plan) and more items were recalled per category (which reflects participants' encoding strategy) when pictures served as stimuli compared to words. Cognitive status and working memory span were correlated with picture and word recall. Regression analyses confirmed that these individual difference variables accounted for significant age-related variance in recall. These data strongly suggest that the oldest-old can utilise nonverbal memory codes to support long-term retention as effectively as do younger adults.     

The role of imagery in incidental learning of educable retarded and normal children

Forty-five educable retarded and 45 normal children were given an orientation task in which noun- and picture-paired associates were presented once or four times under one of three instructional conditions: intentional imagery, incidental imagery, or intentional control (no imagery). An immediate associative recall test showed both imagery conditions to be superior to the intentional control condition. Furthermore, imagery instructions facilitated incidental recall of the retarded Ss equal to the recall of normal children in the intentional condition. Four presentations of pairs in contrast to one presentation during the orientation task improved the learning of both groups. The recall of retarded Ss in contrast to normal Ss, however, was greater with four presentations under imagery instructions than under intentional control instructions. The results were discussed in terms of imagery processes and their educational implications.