Survival processing occupies the central bottleneck of cognitive processing: A psychological refractory period analysis.

Words judged for relevance in a survival situation are remembered better than words judged for relevance in a nonsurvival context. This survival processing effect has been explained by selective tuning of human memory during evolution to process and retain information specifically relevant for survival. According to the richness-of-encoding hypothesis the survival processing effect arises from a domain-general mechanism-namely, a particularly rich and distinct form of encoding. This form of information processing is effortful and requires limited cognitive capacities. In our experiment, we used the well-established psychological refractory period framework in conjunction with the effect propagation logic to assess the role of central cognitive resources for the survival processing effect. Our data demonstrate that the survival memory advantage indeed relies on the capacity-limited central stage of cognitive processing. Thus, rating words in the context of a survival scenario involves central processing resources to a greater amount than rating words in a nonsurvival control condition. We discuss implications for theories of the survival processing effect.

Memory as a cognitive requirement for reciprocal cooperation.

Memory has evolved to guide our decisions in the present and to prepare us for future interactions with the environment. Within the social domain, memory can help to decide with whom to cooperate. This provides a unique opportunity to study memory from a functional perspective. Although several lines of research have demonstrated that many forms of reciprocal cooperation require memory, most of the research does not support the assumption of a highly specialized cheater-detection module that specifically serves to promote the detection of uncooperative interaction partners. Instead, the literature supports the flexible recruitment of domain-general guessing and memory mechanisms that serve to continuously predict the future behavior of others based on situational and person-specific factors and use violations of these expectations to update the predictive models of who can be trusted to cooperate in reciprocal interactions.

Realistic context doesn't amplify the survival processing effect: Lessons learned from Covid-19 scenarios.

Imagining being stranded in the grasslands of an unknown territory without basic survival materials and subsequently rating the relevance of words for this situation leads to exceptionally good memory for these words. This survival processing effect has received much attention, primarily because it has been argued to disclose the evolutionary foundations of human memory. So far, only fictitious scenarios were used to demonstrate this effect. To provide a fairer test of emotional response against richness-of-encoding explanations of the effect, we aimed at increasing everyday relevance and realism of the survival scenarios. For this purpose, we created two new Covid-19 scenarios, one focusing on emotional response (Covid-19-emotion) and the other on survival strategy (Covid-19-strategy). Both new scenarios were compared to the classical grassland and moving scenarios typically used to investigate the survival processing effect. In Experiment 1, we observed better memory for the grassland and Covid-19-strategy scenarios compared to the other two, but no significant difference between the former. A descriptively similar result pattern emerged in Experiment 2 for the number of ideas generated on how to use objects in the four scenarios. Theoretical implications are discussed.

Remembering the bad ones: Does the source memory advantage for cheaters influence our later actions positively?

Previous research has demonstrated that people remember information that is (emotionally) incongruent to their expectations, but it has left open the question if this memory enhancement has also an influence on our later actions. We investigated this question in one pilot study and two experiments. In all studies, participants first interacted with trustworthy and untrustworthy looking partners in an investment game. Facial trustworthiness was manipulated to stimulate social expectations about the behaviour of the partners. In a later second investment game, participants played against old opponents from the first game and new opponents. Overall, willingness to cooperate in the second game was influenced by the formerly behaviour of the opponent. However, facial trustworthiness affected economic decisions, too. Furthermore, we analysed source memory data that indicated no differences in memory between cheaters and cooperators. Instead, source guessing was related to cooperation: The more participants guessed that an untrustworthy looking face belonged to a cheater, the less they cooperated with untrustworthy looking opponents. Interestingly, in Experiment 2, we found a positive correlation between old-new recognition and later cooperation. In sum, the results demonstrate that memory and guessing processes can influence later decisions. However, economic decisions are also heavily affected by other social expectations like facial trustworthiness.

The effectiveness of the loci method as a mnemonic device: Meta-analysis.

The "loci method" is a popular mnemonic device that involves visualising and recalling items at specific points along a familiar route. The loci method has been used for thousands of years, and by many successful memory athletes; yet there have been relatively few educational and clinical applications, possibly owing to empirical uncertainty. The current meta-analysis of 13 randomised controlled trials (RCTs) mostly based in university settings demonstrated the effectiveness of the loci method as a mnemonic device, with a medium effect size (g = 0.65, 95% confidence interval [CI] = [0.45, 0.85]; I2 = 45.5%). The effect size remained at similar levels in further analyses adjusting for publication bias, the impact of removing each study, setting, control conditions, outliers, and number of loci method sessions. High risk of experimental bias was indicated, however, as the vast majority of studies did not report procedures to minimise biases relating to random sequence generation and allocation concealment. Overall, this meta-analysis of predominantly university-based RCTs has provided good initial support for the loci method as a mnemonic device and this may encourage future investigations and applications, particularly in educational settings, where it has the potential to improve recall of information relevant to academic success.

How can I use it? The role of functional fixedness in the survival-processing paradigm.

After imagining being stranded in the grasslands of a foreign land without any basic survival material and rating objects with respect to their relevance in this situation, participants show superior memory performance for these objects compared to a control scenario. A possible mechanism responsible for this memory advantage is the richness and distinctiveness with which information is encoded in the survival-scenario condition. When confronted with the unusual task of thinking about how an object can be used in a life-threatening context, participants will most likely consider both common and uncommon (i.e., novel) functions of this object. These ideas about potential functions may later serve as powerful retrieval cues that boost memory performance. We argue that objects differ in their potential to be used as novel, creative survival tools. Some objects may be low in functional fixedness, meaning that it is possible to use them in many different ways. Other objects, in contrast, may be high in functional fixedness, meaning that the possibilities to use them in non-standard ways is limited. We tested experimentally whether functional fixedness of objects moderates the strength of the survival-processing advantage compared to a moving control scenario. As predicted, we observed an interaction of the functional fixedness level with scenario type: The survival-processing memory advantage was more pronounced for objects low in functional fixedness compared to those high in functional fixedness. These results are in line with the richness-of-encoding explanation of the survival-processing advantage.

Adaptive Memory: Independent Effects of Survival Processing and Reward Motivation on Memory.

Humans preferentially remember information processed for their survival relevance, a memorial benefit known as the survival processing effect. Memory is also biased towards information associated with the prospect of reward. Given the adaptiveness of these effects, they may depend on similar mechanisms. We tested whether motivation drives both effects, with reward incentives that are known to boost extrinsic motivation and survival processing perhaps stimulating intrinsic motivation. Accordingly, we manipulated survival processing and reward incentive independently during an incidental-encoding task in which participants chose between pairs of words concerning their relevance for a scenario, and examined the effects on encoding event-related potentials (ERP) activity and later performance on a surprise recall test. We hypothesized that if survival processing fosters intrinsic motivation, it should reduce the beneficial effects of extrinsic motivation (reward incentive). In contrast to this prediction, we found that reward incentive and survival processing independently improved memory and that the P300, a measure of lower-level cognitive resource allocation, was increased by reward incentive independent of survival processing. Further, survival processing and reward incentive independently increased the frontal slow wave (FSW), a measure of higher-level elaboration. These findings suggest that while survival processing and reward incentive may both increase encoding elaboration, the memory-enhancing effect of survival processing does not depend on increased intrinsic motivation. Additionally, we replicated a recent finding whereby the survival processing effect generalizes to a choice-based encoding task and further showed that the beneficial effect of choice on memory likely does not interact with either survival processing or reward.

Impaired memory for cooperative interaction partners in borderline personality disorder.

BACKGROUND: Interpersonal disturbances in Borderline Personality Disorder (BPD) have been attributed to a negativity bias in social cognition. Adding to this literature, we experimentally tested whether those with BPD show altered memory for cooperative versus non-cooperative interaction partners. METHODS: In a source memory paradigm, 51 female BPD patients and 50 healthy controls (HC) played a trust game with 40 different female target characters (trustworthy vs untrustworthy). In a subsequent surprise memory test, participants had to recognize those target individuals (vs distractor pictures), and had to recall whether they had shown cooperative behavior during the trust game. We hypothesized that BPD patients have better memory for uncooperative interaction partners as compared to cooperative interaction partners, and that a-priori expectations of untrustworthiness would influence recall. RESULTS: During the trust game, BPD individuals invested lower amounts of money than HC for trustworthy targets, but no differences were found for untrustworthy targets. During the memory test, BPD patients had significant difficulties to remember cooperative targets, as compared to HC. More specifically, those with BPD indicated more often than HC that they had not previously interacted with cooperative targets of the previous trust game. We did not detect any differences between BPD and HC in source memory, or with regard to the effects of trustworthiness expectations. CONCLUSIONS: The observed tendency to forget cooperative interaction partners in BPD is possibly caused by dysfunctional cognitive schemas. At the same time, it might also corroborate patients' assumptions that others are untrustworthy, thereby fuelling interpersonal disturbances in BPD.

Survival processing modulates the neurocognitive mechanisms of episodic encoding.

Memories formed in the context of an imagined survival scenario are more easily remembered, but the mechanisms underlying this effect are still under debate. We investigated the neurocognitive processes underlying the survival processing effect by examining event-related potentials (ERPs) during memory encoding. Participants imagined being either stranded in a foreign land and needing to survive, or in an overseas moving (control) scenario, while incidentally encoding a list of words. Words encountered in the survival context were associated with improved recall and reduced false-memory intrusions during a later memory test. Survival processing was associated with an increased frontal slow wave, while there was no effect on the overall P300 amplitude, relative to the control scenario. Furthermore, a subsequent memory effect in the P300 time window was found only in the control scenario. These findings suggest that survival processing leads to a shift away from lower level encoding processes, which are sensitive to motivation and stimulus salience and which were evident in the control scenario, to more active and elaborative forms of encoding. The results are consistent with a richness of encoding account of the survival processing effect and offer novel insights into the encoding processes that lead to enhanced memory for fitness-relevant information.

Easy on the mind, easy on the wrongdoer? No evidence for perceptual fluency effects on moral wrongness ratings.

Processing fluency-the subjective ease of information processing-influences a variety of judgments (e.g., judgments of familiarity, liking, and truth). A study by Laham, Alter, and Goodwin (2009) suggests that this is also true for moral judgments. More specifically, the authors found that discrepant perceptual fluency mitigates moral wrongness ratings. In five studies (total N = 694), we tested the replicability of this finding for different kinds of scenarios (moral versus conventional transgressions) and different perceptual fluency manipulations. In Studies 1a and 1b we manipulated fluency by text background, in Studies 2a and 2b by font type, and in Study 3 by word spaces. Critically, none of the studies replicated Laham et al.'s discrepant fluency effect on moral wrongness ratings. In turn, we found that moral wrongness ratings were strongly affected by participants' emotional responses to the scenarios. Taken together, the findings of our five studies cast very strong doubt on perceptual fluency effects on moral judgments.

Interindividual Differences in the Sensitivity for Consequences, Moral Norms, and Preferences for Inaction: Relating Basic Personality Traits to the CNI Model.

Research on moral decision making usually focuses on two ethical principles: the principle of utilitarianism (= morality of an action is determined by its consequences) and the principle of deontology (= morality of an action is valued according to the adherence to moral norms regardless of the consequences). Criticism on traditional moral dilemma research includes the reproach that consequences and norms are confounded in standard paradigms. As a remedy, a multinomial model (the CNI model) was developed to disentangle and measure sensitivity to consequences (C), sensitivity to moral norms (N), and general preference for inaction versus action (I). In two studies, we examined the link of basic personality traits to moral judgments by fitting a hierarchical Bayesian version of the CNI model. As predicted, high Honesty-Humility was selectively associated with sensitivity for norms, whereas high Emotionality was selectively associated with sensitivity for consequences. However, Conscientiousness was not associated with a preference for inaction.

On the role of retrieval processes in the survival processing effect: Evidence from ROC and ERP analyses.

Memory is enhanced for words encoded in the context of an imagined survival scenario, an effect modulated by word imageability or concreteness. However, the mechanisms underlying this "survival processing effect" are still controversial. To address this issue, we used receiver operating characteristic (ROC) curves and event-related potentials (ERPs) to examine the recognition retrieval processes associated with words previously encoded in either a survival or a control scenario. More specifically, we investigated how recollection- and familiarity-based retrieval are influenced by survival processing of high- and low-imageability words. Participants incidentally encoded words and then completed a surprise recognition test while their EEG was recorded. The encoding of concrete, high-imageability words in a survival context lead to improved recognition memory compared to the control context, and this improvement was associated with an increase in both the ROC and ERP measures of recollection-based memory retrieval. Survival processing was also associated with an increase in the ERP familiarity signal for these words, but the ROC analysis indicated that recognition judgments relied upon recollection rather than familiarity. These findings provide evidence that survival processing increases elaboration during encoding, leading to greater recollection at retrieval and, in turn, enhanced memory.

Remembering the place with the tiger: Survival processing can enhance source memory.

Rating the relevance of words for survival in the grasslands of a foreign land often leads to a memory advantage. However, it is as yet unclear whether the survival processing effect generalizes to source memory. Here, we examined whether people have enhanced source memory for the survival context in which an item has been encountered. Participants were asked to make survival-based or moving-based decisions about items prior to a classical source memory test. A multinomial model was used to measure old-new discrimination, source memory, and guessing biases separately. We replicated the finding of a survival advantage in old-new recognition. Extending previous results, we also found a survival-processing advantage in source memory. These results are in line with the richness-of-encoding explanation of the survival processing advantage and with an adaptive perspective on memory.

Is he important to me? Source memory advantage for personally relevant cheaters.

A popular assumption in evolutionary psychology claims that reciprocal altruism is supported by a cognitive module that helps individuals to detect and remember cheaters. Previous studies found a source memory advantage for faces of cheaters rather than faces of cooperators. The present study examines memory for social-exchange relevant information. More precisely, faces were shown together with behavior descriptions of cheating, trustworthy and neutral behavior either high or low in relevance for a student population. A multinomial model was used to measure old-new discrimination, source memory, and guessing biases separately. The study showed a source memory advantage for cheaters high in relevance. However, source memory for trustworthy persons low and high in relevance was also enhanced. The results are in line with the assumption of a flexible mechanism that focuses on exchange-relevant information. A system that is able to take into account the relative significance of information may be more beneficial than a system focusing on every cheater independently of his or her relative importance.

The effects of item material on encoding strategies: Survival processing compared to the method of loci.

When imagining being stranded in the grasslands of a foreign land without any basic survival material, participants have a magnificent memory for words rated according to their usefulness in this particular situation. Numerous studies could demonstrate that survival processing boosts memory performance more than other memory enhancing techniques. The method of loci is an old mnemonic strategy used to enhance serial recall. This method encompasses navigating mentally through a familiar environment and placing the to-be-remembered items in specific locations. In the later recall phase, the participant re-imagines walking through the environment, "looking" for the to-be-remembered items. In two studies, we compared the survival scenario with the method of loci and two different control conditions. In addition, we manipulated the used word-material on two different dimensions (imageability and relevance) to analyse its influences on the two methods. For words high in imageability, we found that memory performance in the survival condition is comparable to the method of loci. However, for words low in imageability the method of loci proved to be more effective than survival processing. Furthermore, we found that survival relevance has a high impact on the amount of the survival processing effect, even when imageability is low.

What kind of processing is survival processing? : Effects of different types of dual-task load on the survival processing effect.

Words judged for their relevance in a survival context are remembered better than words processed in non-survival contexts. This phenomenon is known as the survival processing effect. Recently, inconsistent results were reported on whether the size of the survival processing effect is affected by cognitive load. Whereas Kroneisen, Rummel, and Erdfelder (Memory 22: 92-102, 2014) observed that the survival processing effect vanishes under dual-task conditions, Stillman, Coane, Profaci, Howard, and Howard (Memory & Cognition 42: 175-185, 2014, Experiment 1) found that the size of survival processing effect is essentially unaffected by a cognitively demanding secondary task. In three experiments, we investigated the differences between these studies to achieve a better understanding of dual-task effects on the survival-processing advantage. In the first experiment, we replicated Stillman et al.'s results using their dual-task conditions combined with a sample more than twice as large as theirs. In the second experiment, we compared dual-task conditions that differed regarding how strongly the secondary task taxed (a) working memory load (maintenance of one vs. several items) and (b) processing demands (switching vs. time-sharing between tasks). A third experiment focussed on low (i.e., single-item) load under time-sharing processing conditions. Results consistently showed that the survival processing effect persisted under low load but vanished when the number of items held in working memory increased beyond one, irrespective of processing demands. Implications of these findings for explanations of the survival-processing advantage are discussed.

Expectancy effects in source memory: how moving to a bad neighborhood can change your memory.

Enhanced memory for cheaters could be suited to avoid social exchange situations in which we run the risk of getting exploited by others. Several experiments demonstrated that we have better source memory for faces combined with negative rather than positive behavior (Bell & Buchner, Memory & Cognition, 38, 29-41, 2010) or for cheaters and cooperators showing unexpected behavior (Bell, Buchner, Kroneisen, Giang, Journal of Experimental Psychology: Learning, Memory, and Cognition, 38, 1512-1529, 2012). In the present study, we compared two groups: Group 1 just saw faces combined with aggressive, prosocial or neutral behavior descriptions, but got no further information, whereas group 2 was explicitly told that they would now see the behavior descriptions of very aggressive and unsocial persons. To measure old-new discrimination, source memory, and guessing biases separately, we used a multinomial model. When having no expectancies about the behavior of the presented people, enhanced source memory for aggressive persons was found. In comparison, source memory for faces combined with prosocial behavior descriptions was significantly higher in the group expecting only aggressive persons. These findings can be attributed to a mechanism that focuses on expectancy-incongruent information, representing a more flexible and therefore efficient memory strategy for remembering exchange-relevant information.

Working memory load eliminates the survival processing effect.

In a series of experiments, Nairne, Thompson, and Pandeirada (2007) demonstrated that words judged for their relevance to a survival scenario are remembered better than words judged for a scenario not relevant on a survival dimension. They explained this survival-processing effect by arguing that nature "tuned" our memory systems to process and remember fitness-relevant information. Kroneisen and Erdfelder (2011) proposed that it may not be survival processing per se that facilitates recall but the richness and distinctiveness with which information is encoded. To further test this account, we investigated how the survival processing effect is affected by cognitive load. If the survival processing effect is due to automatic processes or, alternatively, if survival processing is routinely prioritized in dual-task contexts, we would expect this effect to persist under cognitive load conditions. If the effect relies on cognitively demanding processes like richness and distinctiveness of encoding, however, the survival processing benefit should be hampered by increased cognitive load during encoding. Results were in line with the latter prediction, that is, the survival processing effect vanished under dual-task conditions.

Sex, cheating, and disgust: enhanced source memory for trait information that violates gender stereotypes.

The present study examines memory for social-exchange-relevant information. In Experiment 1 male and female faces were shown together with behaviour descriptions of cheating, altruistic, and neutral behaviour. Previous results have led to the hypothesis that people preferentially remember schema-atypical information. Given the common gender stereotype that women are kinder and less egoistic than men, this atypicality account would predict that source memory (that is, memory for the type of context to which a face was associated) should be enhanced for female cheaters in comparison to male cheaters. The results of Experiment 1 confirmed this hypothesis. Experiment 2 reveals that source memory for female faces associated with disgusting behaviours is enhanced in comparison to male faces associated with disgusting behaviours. Thus the atypicality effect generalises beyond social-exchange-relevant information, a result which is inconsistent with the assumption that the findings can be ascribed to a highly specific cheater detection module.

The proximate memory mechanism underlying the survival-processing effect: richness of encoding or interactive imagery?

Nairne and collaborators showed that assessing the relevance of words in the context of an imagined survival scenario boosts memory for these words. Although this survival-processing advantage has attracted a considerable amount of research, little is known about the proximate memory mechanism mediating this effect. Recently, Kroneisen and Erdfelder (2011) argued that it is not survival processing itself that facilitates recall but rather the richness and distinctiveness of encoding that is triggered by the survival-processing task. Alternatively, however, it is also conceivable that survival processing fosters interactive imagery, a process known to improve associative learning. To test these explanations we compared relevance-rating and interactive imagery tasks for survival and control scenarios. Results show that the survival advantage replicates in the relevance-rating condition but vanishes in the interactive imagery condition. This refutes the interactive imagery explanation and corroborates the richness-of-encoding hypothesis of the survival-processing effect.