Successive vs simultaneous processing of superimposed visual stimuli

A visual analogue of Savin’s (1967) auditory task was used to examine preferred order of recall and order of recall accuracy for two pairs of visually superimposed digits. Savin (1967) and Rollins, Everson, and Schurman (1972) found that Ss preferred to recall simultaneous auditory information in successive order, even though the information was presented over a single channel. In the present experiments, Ss were found to prefer strongly to recall visual information in simultaneous order. On the other hand, the results of Rollins et al (1972), that Ss are equally accurate when forced to recall simultaneous auditory information in either the preferred or nonpreferred mode, were replicated for this visual task. The results of these experiments, together with the experiment reported by Rollins et al (1972), indicate that verbal information is processed differently by these two sensory systems.     

Auditory versus visual processing of three sets of simultaneous digit pairs.

Two experiments were conducted to determine whether the auditory and visual systems process simultaneously presented pairs of alphanumeric information differently. In Experiment 1, different groups of subjects were given extensive practice recalling pairs of superimposed visual or auditory digits in simultaneous order (the order of arrival) or successive order (one member of each digit pair in turn, followed by the other pair member). For auditory input, successive order of recall was more accurate, particularly for the last two of three pairs presented, whereas for visual input, simultaneous order of recall was more accurate. In Experiment 2, subjects were cued to recall in one or the other order either immediately before or after stimulus input. Recall order results were the same as for Experiment 1, and precuing did not facilitate recall in either order for both modalities. These results suggest that processing in the auditory system can only occur successively across time, whereas as in the visual system processing can only occur simultaneously in space.     

Selective listening and threshold for tones appearing on a relevant and on an irrelevant input channel

Threshold scores for tones appearing on shadowed and on nonshadowed messages were obtained in order to test whether input presented on an irrelevant channel is attenuated when Ss attend to another channel. Comparisons were made between threshold scores obtained for each ear, when Ss shadowed messages appearing on that ear and when Ss shadowed messages appearing on the contralateral ear. The threshold scores in the two conditions were highly similar. Data are evaluated in the context of auditory target detection, with targets identified by their verbal content vs their physical characteristics.     

Children's recall strategies in dichotic listening

Normal adults spontaneously adopt different recall strategies in reporting dichotic material presented at different rates. A channel by channel or ear order is used with the faster rate of input and a pair by pair or temporal order is used with the slower rate of input. The purpose of the present report is to study the frequency of the different orders of report in children as a function of the rate of input of dichotic stimulation. Twenty-four normal children, 9–10 years of age, were given the dichotic listening task under three rate conditions. The children used different recall strategies as a function of rate of input in the same manner as that reported for adults. In addition, the order of presentation of the different rates of input was found to influence the relative frequency of the different recall strategies. A significant positive correlation was found between intelligence and the frequency of use of only the temporal recall strategy in its appropriate (slow) rate condition.     

Part-list recall following part-whole learning

Following five trials of part-list free recall learning and six trials of whole-list free recall learning, Ss were asked to recall the part-list items on two successive trials. Experimental Ss whose whole list contained all of the part-list items recalled more part-list items than did control Ss whose whole list contained none of the part-list items. The data are inconsistent with current notion of subjective organization.     

Fluctuations in recall across successive test trials

The purpose of the experiment was to determine whether item fluctuation (intertrial forgetting and spontaneous recovery) depends upon the time allowed for recall and/or the demand characteristics of the experimental situation (manipulated via instructions to S). One hundred. and forty-four university undergraduates studied a 36-item list and then had two successive recall trials which were 9, 36, or 144 sec in duration. On the second recall trial, Ss were instructed to recall previously recalled items only (“old”), previously nonrecalled items only (“new”), or both previously recalled items and previously nonrecalled items (“both”). The results suggest two conclusions: (1) Although recall trial duration affects the overall amount of recall, it does not affect the amount of item fluctuation; and (2) an instruction to recall only “old” items or to recall only “new” items results in suppression of the nonrequested items without a corresponding facilitation for the requested items.     

Stimulus array and recall method as variables in audio-visual split-span memory

Performance on an audio-visual split-span task was found to be adversely affected by the concurrent operation of two factors, namely: alternation of stimulus classes between the two input messages, and the use of a recall method which entails alternate sampling of the two messages. However, these factors had no significant effect when operating singly. The present study indicated that subjects prefer the strategy of reporting visual items first when using modality recall, and that this strategy is more efficient than that of reporting auditory items first. Also, modality recall proved to be the preferred method under free recall instructions. While there were more visual errors than auditory errors, visual commissions exceeded order errors, but auditory order errors exceeded commissions. The redundancy proposal of the search hypothesis (Yntema and Trask, 1963) was tested, and was found to be inadequate as an account of audio-visual performance.     

Right-ear advantage and delayed recall

Two studies were performed using monaural presentation of verbal material to test for a right-ear advantage (REA) in recall. It was hypothesized that a delayed recall task and examination of the serial position curve would be a more sensitive test for ear asymmetries than those used in previous studies. In Experiment 1, 30 right-handed male subjects were given lists of words to recall, presented to either the left or right ear, with language chatter, baroque music, or no stimulus concurrently presented to the opposite ear. Both immediate and delayed recall were assessed. The results indicated that the strongest REAs appeared in delayed recall. Moreover, the REAs occurred regardless of the stimulus conditions co-occurring in the other ear. Experiment 2 was done to test whether the REAs in the delayed recall were due to rehearsal biases. Twenty-four right-handed male subjects recalled lists of words with standard instructions and instructions to recall in the reverse order of input (limiting rehearsal). The results indicated that the backward instructions limited and controlled rehearsal and, hence, input to long-term storage; the REAs occurred in delayed recall under all instructional conditions.     

Monaural and binaural story recall by schizophrenic subjects.

P. Green and other investigators have reported that schizophrenic Ss have poorer recall of stories presented to both ears than to the single best ear (binaural deficit) and poorer recall of stories presented to the left ear than to the right ear (monaural asymmetry) than do normal control Ss. These studies are plagued by potential methodological problems, including differences in overall accuracy, which artifactually affect the difference scores, and scoring methods that are vulnerable to systematic bias. In this study, scores of schizophrenic, bipolar, and normal control Ss on the Auditory Comprehension Test were compared. Scoring bias was avoided by the use of blind scoring and a revised scoring manual, and artifactual effects of accuracy were considered in interpreting the results. Contrary to previous findings, the groups did not differ on either monaural asymmetry or binaural deficit.     

The effects of learning instructions and cueing on free recall

Eighty unrelated high-imagery words were presented for free recall learning in groups of four words each. Learning instructions were varied, with one group told to relate the words in each input group by means of images, another group told to use verbal (sentence) mediators, and the control group not given specific learning instructions. During recall, list items were presented as retrieval cues in some conditions. In comparison with the control condition, imagery and verbal mediation instructions produced greater recall, more clustering, and a largez number of instances per group recalled. When the retrieval cues were selected such that one cue came from each of the input groups and when the strength of within-group organization was quite high, Ss recalled more words and a larger number of input groups. It was concluded that instructions and cueing conditions influenced different aspects of the free recall process. Instructions influenced the organization of individual words into units, and cueing affected the retrieval of specific units.     

Understanding the dynamics of correct and error responses in free recall: Evidence from externalized free recall

The dynamics of correct and error responses in a variant of delayed free recall were examined in the present study. In the externalized free recall paradigm, participants were presented with lists of words and were instructed to subsequently recall not only the words that they could remember from the most recently presented list, but also any other words that came to mind during the recall period. Externalized free recall is useful for elucidating both sampling and postretrieval editing processes, thereby yielding more accurate estimates of the total number of error responses, which are typically sampled and subsequently edited during free recall. The results indicated that the participants generally sampled correct items early in the recall period and then transitioned to sampling more erroneous responses. Furthermore, the participants generally terminated their search after sampling too many errors. An examination of editing processes suggested that the participants were quite good at identifying errors, but this varied systematically on the basis of a number of factors. The results from the present study are framed in terms of generate-edit models of free recall.     

An adjacency effect in free recall

An adjacency effect was demonstrated at a high level of significance in the free recall, by 123 subjects, of a list of 40 high-frequency nouns presented in varying order on successive trials. The phenomenon referred to as the adjacency effect consists of the fact that when a subject is given repeated trials of study and free recall of a list of words (always presented in a different order), the probability of recalling a given item is greater when the item is presented temporally adjacent to an item which is already learned (as evidenced by recall on the previous trial) than when the item stands temporally between other items which are not yet learned. The enhancement of recall is greater when the item is presented between two previously learned items. The implications of the adjacency effect for verbal learning theory, particularly for the serial-position effect in serial learning and the concepts of interference and neural consolidation, are discussed.     

Attention in bisensory simultaneous short-term memory

Subjects were presented with simultaneously visual and auditory material. They were instructed to attend to only one modality but were required to recall materials from both modalities, one before the other. Results supported a previous suggestion that visual recall is minimum under conditions of simultaneous presentation. That is, in situations where S is allowed to divide his attention between both inputs, visual recall was no greater than when his attention was directed away from visual input and to auditory input. It was noted that this difference in recall between the two modalities was limited to verbal material, as other data indicate the opposite effect for nonverbal material.     

Free association,free recall,and stimulated recall compared

Three primary methods of recall (free association, free recall, stimulated recall) and two modifications of them (modified free association, modified stimulated recall) were defined by use of three variables: (a) presence or absence of prior laboratory training, (b) presence or absence of E controlled test stimulation, and (c) test instructions to free associate or to recall Data obtained from approximately 300 Ss and an earlier set of 600 revealed the differential effectiveness of all three primary methods in recall and misrecall.     

Sequential consistency and subjective clustering in the multitrial free recall of children

The organization imposed by children on lists presented in a multitrial free recall task was investigated in two experiments. In the first, 6 and 9 year olds were tested for multitrial free recall of an unstructured noun or mixed list, followed by two sorting trials. Organization was quantified using two structurally comparable indices. One was an index of subjective clustering, based on individual word groupings determined in the sorting trials, and the other was an index of the sequential consistency of recall order over successive trials. The older children had significantly higher scores on recall and subjective clustering but there was no age effect on sequential consistency. In the second experiment 6, 8 and 10 year olds were tested for multitrial free recall of line drawings of common objects. Two sorting trials followed and organization was quantified using the subjective clustering and sequential consistency indices. Recall and subjective clustering scores again showed significant increases with age. As before, no age effect on sequential consistency was found. The results were interpreted in terms of a differential sensitivity of the two indices to an age-related qualitative change in the basis of organization.     

Encoding differences in recognition and recall

After practice consisting of the free recall of five blocked categorized lists, Ss were presented a sixth list and then unexpectedly tested for recognition. After practice at recognition of the same five lists, Ss were unexpectedly tested for recall following presentation of the sixth test. Recognition performance was superior when items were encoded in anticipation of a recognition test. Intracategory serial position functions for Ss anticipating recall tests were different from those anticipating recognition tests regardless of the retention test employed. The role of control processes in recall and recognition testing is discussed     

False memories are hard to inhibit: differential effects of directed forgetting on accurate and false recall in the DRM procedure

Directed forgetting research shows that people can inhibit the retrieval of words that they were previously instructed to forget. The present research applied the directed forgetting procedure to the Deese/Roediger and McDermott (DRM) recall task to determine if directed forgetting instructions have similar or different effects on accurate and false memory. After studying lists of semantically related words, some participants were told to forget those lists, whereas other participants were not. All participants were then shown additional lists to remember. Following study, all participants were asked to free recall as many of the studied words as possible, including those they were previously instructed to forget. Directed forgetting instructions inhibited the accurate recall of studied words, but not the false recall of nonstudied critical words, whether measured by a within-participant or between-participants design. Contrary to an implicit activation hypothesis, false memories survived instructions to forget. These findings were reviewed in terms of fuzzy trace theory and the activation/monitoring approach to false memory.     

Stimulus information and stimulus interference in bisensory short-term memory

An attempt was made to determine if Ss’ strategy of retaining stimulus material changed under conditions of bisensory simultaneous stimulation when one of the two inputs was relevant information as opposed to interference. Thus in Group 1 Ss were stimulated bisensorily, attended to both inputs (information), but recalled only one input. Ss in Group 2 were stimulated bisensorily, attended to only one input, and recalled only that input (interference). It was found that S’s efficiency of recall was decreased in the information condition (Group 1) but strategy was not altered. In both groups, Ss performed similarly; performance was in turn similar to that observed in the typical bisensory situation, i.e., where both channels are recalled.     

Need for Cognition and false recall

Two experiments investigated whether Need for Cognition (NFC) affected false recall in the Deese-Roediger-McDermott (DRM) paradigm. In the first experiment, participants were presented with DRM lists and given one attempt to recall the items. In the second experiment, participants were presented with DRM lists under full or divided attention and were given three consecutive recall tests. In Experiment 2, high-NFC individuals exhibited increased false recall across successive recall attempts in both the full and divided attention conditions whereas low-NFC individuals did not. Furthermore, high-NFC individuals in the full attention condition exhibited increased levels of true recall across successive tests. These results show that the individual differences in the ways in which individuals process information can affect true and false recall in the DRM task.     

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.