Recency and suffix effects with immediate recall of olfactory stimuli

In contrast to our understanding of the immediate recall of auditory and visual material, little is known about the corresponding characteristics of short-term olfactory memory. The current study investigated the pattern of immediate serial recall and the associated suffix effect using olfactory stimuli. Subjects were trained initially to identify and name correctly nine different odours. Experiment 1 established an immediate correct recall span of approximately six items. In Experiment 2 participants recalled serially span equivalent lists which were followed by a visual, auditory, or olfactory suffix. Primacy was evident in the recall curves for all three suffix conditions. Recency, in contrast, was evident in the auditory and visual suffix conditions only; there was a strong suffix effect in the olfactory suffix condition. Experiment 3 replicated this pattern of effects using seven-item lists, and demonstrated that the magnitude of the recency and suffix effects obtained in the olfactory modality can equate to that obtained in the auditory modality. It is concluded that the pattern of recency and suffix effects in the olfactory modality is reliable, and poses difficulties for those theories that rely on the presence of a primary linguistic code, sound, or changing state as determinants of these effects in serial recall.     

Recency and suffix effects with immediate recall of olfactory stimuli

In contrast to our understanding of the immediate recall of auditory and visual material, little is known about the corresponding characteristics of short-term olfactory memory. The current study investigated the pattern of immediate serial recall and the associated suffix effect using olfactory stimuli. Subjects were trained initially to identify and name correctly nine different odours. Experiment 1 established an immediate correct recall span of approximately six items. In Experiment 2 participants recalled serially span equivalent lists which were followed by a visual, auditory, or olfactory suffix. Primacy was evident in the recall curves for all three suffix conditions. Recency, in contrast, was evident in the auditory and visual suffix conditions only; there was a strong suffix effect in the olfactory suffix condition. Experiment 3 replicated this pattern of effects using seven-item lists, and demonstrated that the magnitude of the recency and suffix effects obtained in the olfactory modality can equate to that obtained in the auditory modality. It is concluded that the pattern of recency and suffix effects in the olfactory modality is reliable, and poses difficulties for those theories that rely on the presence of a primary linguistic code, sound, or changing state as determinants of these effects in serial recall.     

Suffix effects in lists of temporally grouped words

Two groups of university students were presented with auditory lists of temporally grouped words for recall. The lists were immediately followed by either a redundant suffix, a nonredundant suffix or no suffix. One group of subjects was instructed to recall the items in strict serial order; the second group was required to write the last items first, indicating the position of all items in the list. According to Kahneman's (1973) account of the suffix effect, the interfering effect of the suffix should be eliminated when the suffix is segregated in a different group or perceptual unit from the memory items. The results did not support the prediction from Kahneman's hypothesis. An alternative account of the suffix effect was presented.     

Echoic and retrieval accounts of the long-term modality effect tested using the suffix procedure

The long-term modality effect is the advantage in recall of the last of a list of auditory to-be-remembered (TBR) items compared with the last of a list of visual TBR items when the list is followed by a filled retention interval. If the auditory advantage is due to echoic sensory memory mechanisms, then recall of the last auditory TBR item should be substantially reduced when it is followed by a redundant, not-to-be-recalled auditory suffix. Contrary to this prediction, Experiment 1 demonstrated that a redundant auditory suffix does not significantly reduce recall of the last auditory TBR item. In Experiment 2 a nonredundant auditory suffix produced a large reduction in the last auditory item. Redundancy is not the only factor controlling the effectiveness of a suffix, however. Experiment 3 demonstrated that a nonredundant visual suffix does not reduce recall of the last auditory TBR item. These results are discussed in reference to a retrieval account of the long-term modality effect.     

On the measurement of storage and retrieval contributions to memory development

We report two free recall experiments and a cued recall experiment in which a new two-stage model was used to obtain numerical measurements of age changes in various aspects of storage and retrieval. The subjects in all three experiments were 7-year-olds (second graders) and 11-year-olds (sixth graders). The major findings in the free recall experiment were that getting a trace into storage posed less of a problem for elementary schoolers than learning how to get it out on test trials, that retrieval development is more rapid during the elementary school years than storage development, and that the superiority of older children's storage and retrieval abilities tends to become more pronounced as learning progresses. A similar pattern of results was obtained under different conditions in the cued recall experiment.     

Developmental changes in the effects of types of self-corrected elaboration on incidental memory

The present study investigated the developmental changes in the effects of two types of self-corrected elaboration, namely generated correction and chosen correction, on incidental memory of words. Second and sixth graders performed an orienting task involving two types of correction followed by an unexpected recall test. They were presented with a target and its sentence, and were asked to correct the target to a congruous word in the generated-correction condition, or to choose one of the alternative congruous words in the chosen-correction condition. For second graders, chosen correction led to a better recall than generated correction, whereas for sixth graders the reverse relationship between the two corrections was observed. These results were interpreted as showing the developmental change in the effects of types of self-corrected elaboration on incidental memory.     

Abstract versus modality-specific memory representations in processing auditory and visual speech

Serial recall of lip-read, auditory, and audiovisual memory lists with and without a verbal suffix was examined. Recency effects were the same in the three presentation modalities. The disrupting effect of a suffix was largest when it was presented in the same modality as the list items. The results suggest that abstract linguistic as well as modality-specific codes play a role in memory for auditory and visual speech.     

Absence of a cross-modal “suffix effect” in short-term memory

Three experiments are reported involving the presentation of lists of either letters or digits for immediate serial recall. The main variable was the presence or absence of a suffix-prefix, an item (tick or cross) occurring at the end of the list which had to be copied before recall of the stimulus list. With auditory stimuli and an auditory suffix-prefix there was a large and selective increase in the number of errors on the last few serial positions—the typical “suffix effect”. The suffix effect was not found with auditory stimuli and a visual suffix-prefix nor with a visual stimulus and an auditory suffix-prefix. These results are interpreted as supporting a model for short-term memory proposed by Crowder and Morton (1969) in which it is suggested that with serial recall information concerning the final items following auditory presentation has a different, precategorical, origin from that concerning other items.     

Changes in the semantic constraint of spreading activation of memory across three age groups

28 undergraduate, 34 sixth-grade, and 36 second-grade students studied target words embedded in interchangeable or noninterchangeable sentences, and then performed free recall tests. In an interchangeable sentence the word which was to be remembered and its associated word fitted sensibly, whereas in a noninterchangeable sentence the target word fitted sensibly but its word associate did not. Undergraduates recalled the target words in noninterchangeable sentences better than sixth or second graders for whom a difference was not observed (undergraduates > sixth graders = second graders). In interchangeable sentences undergraduates recalled more targets than sixth or second graders, and sixth graders recalled more than second graders (undergraduates > sixth graders > second graders). The results were interpreted as indicating changes across age groups in the semantic constraint of spreading activation of target words in memory.     

The Development of Attribute Dominance in the Knowledge Base

Two cuing, free-recall studies were conducted to test Bach and Underwood's (1970) hypothesis that acoustic encoding is dominant among second graders and semantic encoding is dominant among sixth graders. When retrieval cues were presented with to-be-remembered items at both input and output (Experiment 1), and when cues were presented only at output (Experiment 2), semantic cues were more efficient in elevating recall than were acoustic cues for both second and sixth graders. When these and other results generally found using recognition, sorting, incidental learning, and free-recall experimental designs are compared, it seems plausible that item presentation and memory-testing formats interact with age, and that these factors account for the different patterns of attribute dominance found in the literature. The knowledge base cannot be understood by focusing on either subject or task analyses, but only by focusing on interactions between subject and task variables as they change over time. The educational implications for young grade-school children are discussed.     

Changes across age groups in self-choice elaboration and incidental memory

This study investigated differences in the self-choice elaboration and an experimenter-provided elaboration on incidental memory of 7- to 12-yr.-olds. In a self-choice elaboration condition 34 second and 25 sixth graders were asked to choose one of the two sentence frames into which each target could fit more congruously, whereas in an experimenter-provided elaboration they were asked to judge the congruity of each target to each frame. In free recall, sixth graders recalled targets in bizarre sentence frames better than second graders for self-choice elaboration condition. An age difference was not found for the experimenter-provided elaboration. In cued recall self-choice elaboration led to better performance of sixth graders for recalling targets than an experimenter-provided elaboration in both bizarre and common sentence frames. However, the different types of elaboration did not alter the recall of second graders. These results were interpreted as showing that the effectiveness of a self-choice elaboration depends on the subjects' age and the type of sentence.     

The stimulus suffix effect as a memory coding phenomenon

Two short-term memory experiments examined the nature of the stimulus suffix effect on auditory linguistic and nonlinguistic stimulus lists. In Experiment 1, where subjects recalled eight-item digit lists, it was found that a silently articulated digit suffix had the same effect on recall for the last list item as a spoken digit suffix. In Experiment 2, subjects recalled lists of sounds made by inanimate objects either by listing the names of the objects or by ordering a set of drawings of the objects. Auditory suffixes, either another object sound or the spoken name of an object, produced a suffix effect under both recall conditions, but a visually presented picture also produced a suffix effect when subjects recalled using pictures. The results were most adequately explained by a levels-of-processing memory coding hypothesis.     

The role of memory in attenuations of the suffix effect

Various properties attenuate the auditory suffix effect. These properties may improve recall by allowing the suffix to be excluded from the auditory store (or stores) used for immediate ordered recall, or they may improve recall even though the suffix is included in the auditory store. Nine items were presented, with the last item being either a suffix or another item to be recalled. In Experiment 1, the impairment in recall of the previous items produced by presenting a to-be-recalled last item in a different voice was the same as the impairment produced by presenting a suffix in a different voice. The same result was found in Experiment 2 for presenting the last item in a different spatial location and in Experiment 3 for delaying the presentation of the last item. Apparently the attenuating properties improve recall through memorial factors, and not by allowing the suffix to be excluded from the auditory store.     

Spatial and temporal processing in the auditory and visual modalities

Three experiments tested the idea that auditory presentation facilitates temporal recall whereas spatial recall is better if the input modality is visual. Lists of words were presented in which the temporal and spatial orders were independent, and instructions to the subjects determined whether recall would be given in a spatial or temporal order. In all three experiments, a significant interaction between the input modality and the type of recall was found, such that visual presentation resulted in superior recall over auditory presentation in the spatial conditions and auditory presentation yielded superior recall to visual in the temporal conditions. The present results contradict an earlier study by Murdock that showed that auditory presentation resulted in better performance than visual presentation in a nominally spatial task. An explanation for the discrepancies between the results of that study and the present one is presented.     

Do developmental changes in digit span result from acquisition strategies?

This study tested the theoretical proposition that the developmental increase in memory span results from a corresponding increase in the use of grouping strategies. With slow presentation, experimenter-provided grouping eliminated the span differences between sixth graders and adults but, while grouping helped first graders more than adults, a sizable difference in digit span remained. With fast presentation, grouping increased the adults' performance more than the childrens'. Another finding was that both groups of children had greater digit spans with fast presentation than with slow. For adults, the reverse was true.     

Shadowing in bisensory memory

Shadowing (vocalization-at-presentation) was applied to a bisensory situation where different messages were simultaneously presented to the visual and auditory modalities. Three groups of subjects were employed: Group I shadowed the visual modality; Group II shadowed the auditory modality; Group III was a control, shadowing neither modality. Shadowing in the present experiment facilitated recall of the shadowed modality, particularly the visual modality, which is usually inferior to auditory recall.

It also became apparent that visual recall in an ordinary bisensory situation was minimal if not near an incidental level and that a true bisensory situation with equal division of attention between the two modalities employed does not exist.     

Immediate serial recall of mixed-modality lists

Seven experiments are reported in which subjects were tested for immediate serial recall of mixed-modality lists. On mixed auditory-visual lists, there was an advantage for auditory items at all serial positions. This was due to both a facilitation of auditory items and an inhibition of visual items on mixed lists, as compared with single-modality lists. When presented on a list containing items read silently, recall of items that were silently mouthed by the subject demonstrated patterns similar to those found with auditory items. When presented on a list containing items read aloud, recall of mouthed items showed patterns similar to those found with silently read items. The auditory advantage on mixed lists was found even when the list items were acoustically similar or identical and was not reduced by midlist auditory suffixes. The results suggest that modality differences in recall of mixed-modality lists are based on information different from that responsible for modality differences in recall of single-modality lists.     

The development of attribute dominance in the knowledge base

Two cuing, free-recall studies were conducted to test Bach and Underwood's (1970) hypothesis that acoustic encoding is dominant among second graders and semantic encoding is dominant among sixth graders. When retrieval cues were presented with to-be-remembered items at both input and output (Experiment 1), and when cues were presented only at output (Experiment 2), semantic cues were more efficient in elevating recall than were acoustic cues for both second and sixth graders. When these and other results generally found using recognition, sorting, incidental learning, and free-recall experimental designs are compared, it seems plausible that item presentation and memory-testing formats interact with age, and that these factors account for the different patterns of attribute dominance found in the literature. The knowledge base cannot be understood by focusing on either subject or task analyses, but only by focusing on interactions between subject and task variables as they change over time. The educational implications for young grade-school children are discussed.     

Deviation from hierarchical structure in recall: Is there an “optimal” structure?

Past research has suggested that proportionally more superordinate than sub-ordinate propositions are recalled from expository texts, following a hierarchical analysis of the text structure. Since free recall has typically followed this hierarchical pattern, several researchers have assumed that the related memory structures are isomorphic to the text structure. However, few of these studies have examined how individual differences and text structure interact to affect free recall. In two experiments, the assumption of hierarchical patterns of children's recall of expository text was tested. In Experiment 1, high- and average-ability fourth graders (9 years old) were asked to read and recall a passage. Experiment 2 was a replication and extension of Experiment 1. In this experiment, fourth and sixth graders (9 and 11 years old) read and recalled a different passage. The combined results of both experiments support the notion that there is probably no one optimal hierarchical structure for storage and retrieval of expository text.     

Is there a modality effect? Evidence for visual recency and suffix effects

In Experiment 1, four groups of 16 subjects performed ordered recall of six-syllable lists in both suffix and nonsuffix conditions. Sequential presentation of the lists varied for each group. In the auditory presentation, the syllables were delivered from one location only and were read aloud by the subjects. For the visual, spatially nondistributed presentation, the syllables appeared in one location only and were read silently. For visual, spatially distributed presentations, the syllables were spread out either vertically or horizontally and were read silently. Very robust recency and suffix effects were found in the auditory presentation, as well as in visual, spatially distributed presentations. In Experiment 2, 16 subjects performed ordered recall of visually presented lists with the items spread out vertically and conflicting spatial and temporal orders. A reliable recency effect was found for the final block of trials. In Experiment 3, 16 subjects performed ordered recall in the same conditions as in Experiment 2, except that they were instructed to recall the temporal order in which the spatial positions would be filled in. A bow-shaped curve and a strong recency effect were obtained.