Daniel J. Burns

Adaptive memory: determining the proximate mechanisms responsible for the memorial advantages of survival processing.

J. S. Nairne, S. R. Thompson, and J. N. S. Pandeirada (2007) suggested that our memory systems may have evolved to help us remember fitness-relevant information and showed that retention of words rated for their relevance to survival is superior to that of words encoded under other deep processing conditions. The authors present 4 experiments that uncover the proximate mechanisms likely responsible. The authors obtained a recall advantage for survival processing compared with conditions that promoted only item-specific processing or only relational processing. This effect was eliminated when control conditions encouraged both item-specific and relational processing. Data from separate measures of item-specific and relational processing generally were consistent with the view that the memorial advantage for survival processing results from the encoding of both types of processing. Although the present study suggests the proximate mechanisms for the effect, the authors argue that survival processing may be fundamentally different from other memory phenomena for which item-specific and relational processing differences have been implicated. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

The item-order distinction and the generation effect : The importance of order information in long-term memory

The item-order distinction has been useful in explaining memory dissociations in short-term retention tasks. It generally has been assumed that serial order information is beneficial to long-term retention as well, although the distinction has received little empirical attention. Recently, it was shown that generating items at input, rather than simply reading them, hinders processing of serial order information. This reduction in order processing has been implicated in the lack of generation effects in between-list designs. Experiment 1, using typical generation effect procedures, showed that generation inhibited order reconstruction performance. Experiment 2 showed that order reconstruction was hindered even when categorically related lists were used. Experiment 3 demonstrated that generation inhibited order reconstruction in an incidental learning procedure. The results suggest that order processing is relatively automatic and that generation constantly inhibits it. The results support the view that the item-order distinction may be a powerful explanatory tool in long-term memory research.

An analysis of item gains and losses in retroactive interference.

The repeated-testing paradigm is used to study both retroactive interference and hypermnesia (the improvement in memory across repeated tests). Considerable theoretical progress has been made by separately analyzing the 2 components of hypermnesia: the recovery of previously unrecalled items on later tests (item gains) and the forgetting of previously recalled items on later tests (item losses). Item gains increase with increases in item-specific processing, whereas item losses decrease with increases in relational processing. The authors suggest that separate analysis of item gains and losses in retroactive interference research may also prove fruitful. Three experiments showed that an interpolated list affects item gains but not losses, whereas processing similarity between the target and interpolated lists affects losses but not gains. These results are interpreted within the relational-item-specific processing framework.

Adaptive memory: The survival scenario enhances item-specific processing relative to a moving scenario

Nairne, Thompson, and Pandeirada (2007) found that retention of words rated for their relevance to survival is superior to that of words encoded under numerous other deep processing conditions. They suggested that our memory systems might have evolved to confer an advantage for survival-relevant information. Burns, Burns, and Hwang (2011) suggested a two-process explanation of the proximate mechanisms responsible for the survival advantage. Whereas most control tasks encourage only one type of processing, the survival task encourages both item-specific and relational processing. They found that when control tasks encouraged both types of processing, the survival processing advantage was eliminated. However, none of their control conditions included non-survival scenarios (e.g., moving, vacation, etc.), so it is not clear how this two-process explanation would explain the survival advantage when scenarios are used as control conditions. The present experiments replicated the finding that the survival scenario improves recall relative to a moving scenario in both a between-lists and within-list design and also provided evidence that this difference was accompanied by an item-specific processing difference, not a difference in relational processing. The implications of these results for several existing accounts of the survival processing effect are discussed.

Nothing concentrates the mind: thoughts of death improve recall

It seems likely that awareness of one’s mortality is in some respects advantageous (e.g., because it helps individuals forestall death), but little research has explored the psychological mechanisms that might confer such an advantage. Recent research has shown that processing stimuli in terms of survival relevance enhances memory relative to a host of deep-processing conditions, so it is plausible that human memory has been selected to operate more efficiently when death thoughts (e.g., survival concerns) are activated. If so, then the mortality salience as a general psychological state should be sufficient to increase recall; the present experiments show this to be the case. The enhancing effect of mortality salience on recall occurred for both incidental and intentional learning tasks, relative to a variety of comparison conditions, and did not appear to be mediated by affect or arousal. Follow-up analyses revealed the effect to be mediated by the complexity of participants’ elaborations about mortality. Potential theoretical implications are discussed.

Using cumulative-recall curves to assess the extent of relational and item-specific processing

Although distinguishing between item-specific and relational information has proved to be a useful approach for understanding a variety of important memory phenomena, finding measurement tools for assessing the amount and type of information processed has proven difficult. Using the repeated-testing procedure, Burns (1993) demonstrated that item gains (the recall of items on a later test that were not recalled on earlier tests) and item losses (the forgetting of items on a later test that were recalled on earlier tests) reflected differences in amount of item-specific and relational information processed, respectively. Although several researchers have begun to use the measures with apparent success, the present research demonstrates that the accuracy of the item-gain measure is largely dependent on the rather arbitrary choice of recall-test length. We also show that a related but alternative measure, analysis of cumulative-recall curves, avoids some of the shortcomings of the item gain and loss measures. Moreover, we provide evidence for the generality of the cumulative-recall approach by demonstrating its effectiveness in mixed-list designs.

The bizarre imagery effect and intention to learn

The bizarre imagery effect, better memory for bizarre stimuli than for common stimuli, is now an established finding. However, the mnemonic benefits of bizarre imagery are subject to several constraints (e.g., the use of mixed lists and free-recall tests). A further constraint on the bizarreness effect is demonstrated here. In each of two experiments, subjects were given either incidental or intentional study instructions and were asked to rate the vividness of the images they formed from the bizarre and common sentences. Contrary to conclusions based on available evidence, the bizarreness effect in free recall was manifested only with the incidental learning instructions. This additional constraint on the effect is consistent with the item-order account of bizarreness.

Falsely Recalled Items Are Rich in Item-Specific Information

Current theorizing suggests that critical lures in the Deese/Roediger-McDermott (DRM) procedure are often falsely remembered because they have received considerable relational processing (e.g., spreading activation or encoding of gist information). We used a repeated-testing paradigm to assess the amount of item-specific and relational processing given to the list items and the critical lures. Research has shown that items receiving itemspecific processing are more likely to be recovered across successive tests. They are also output more slowly but more steadily throughout the recall period. In two experiments, we manipulated the processing performed on list items and then used item gains and cumulative recall curves to assess the amount of item-specific and relational information encoded for both list items and lures. The results suggest that increasing the relational processing of list items increased item-specific processing of lures, whereas increasing item-specific processing of list items decreased item-specific processing of lures. We conclude that critical lures are typically rich in item-specific information, relative to list items.

The category access measure of relational processing.

Increases in category access (CA) and items recalled per category (IPC) are associated with increases in relational and item-specific processing, respectively. However, it has also been shown that CA increases as recall level increases and that CA scores following relational processing are actually below CA scores for randomly recalled items. These results prompted M. D. Murphy (1979) to suggest that, after adjusting for recall-level differences, relational processing decreases CA scores. Results of Experiment 1, along with a reanalysis of previously published data, showed that relational processing produces lower CA scores than purely item-specific processing (or random recall), but an increase in relational processing produces an increase in CA scores even when the CA and IPC scores are adjusted for recall-level differences. These results suggest a curvilinear relationship between relational processing and CA scores.

Dying to remember, remembering to survive: Mortality salience and survival processing.

Processing items for their relevance to survival improves recall for those items relative to numerous other deep processing encoding techniques. Perhaps related, placing individuals in a mortality salient state has also been shown to enhance retention of items encoded after the morality salience manipulation (e.g., in a pleasantness rating task), a phenomenon we dubbed the “dying-to-remember” (DTR) effect. The experiments reported here further explored the effect and tested the possibility that the DTR effect is related to survival processing. Experiment 1 replicated the effect using different encoding tasks, demonstrating that the effect is not dependent on the pleasantness task. In Experiment 2 the DTR effect was associated with increases in item-specific processing, not relational processing, according to several indices. Experiment 3 replicated the main results of Experiment 2, and tested the effects of mortality salience and survival processing within the same experiment. The DTR effect and its associated difference in item-specific processing were completely eliminated when the encoding task required survival processing. These results are consistent with the interpretation that the mechanisms responsible for survival processing and DTR effects are overlapping.