Differential Effects of Valence and Encoding Strategy on Internal Source Memory and Judgments of Source: Exploring the Production and the Self-Reference Effect

Does Expecting Matter? The Impact of Experimentally Established Expectations on Subsequent Memory Retrieval of Emotional Words

Previous studies have confirmed that different degrees of expectation, including the bipolarity of the expected and unexpected, as well as an intermediate level (no expectation), can affect memory. However, only a few investigations have manipulated expectation through experimentally established schema, with no consideration of how expectation impacts both item and source memory. Furthermore, stimulus emotionality may also impact memory. Therefore, we conducted a study to investigate the effects of three levels of expectation on item and source memory while considering the impact of stimulus emotionality. The experiment began with a phase dedicated to learning the rules. In the subsequent study phase, negative and neutral words were manipulated as expected, no expectation, and unexpected, based on these rules. This was followed by tasks focused on item and source memory. The study found that there was a "U-shape" relationship between expectation and item memory. Additionally, the study revealed the distinct impacts of expectation on item and source memory. When it came to item memory, both expected and unexpected words were better remembered than those with no expectations. In source memory, expected words showed memory inferiority for expectation-irrelevant source information, but an advantage for expectation-relevant source information. Stimulus emotionality modulated the effect of expectation on both item and source memory. Our findings provide behavioral evidence for the schema-linked interactions between medial prefrontal and medial temporal regions (SLIMM) theory, which proposes that congruent and incongruent events enhance memory through different brain regions. The different patterns between item and source memory also support dual-process models. Moreover, we speculate that processing events with varying levels of emotionality may undermine the impact of expectation, as implied by other neural investigations.

Sensitivity of late ERP old/new effects in source memory to self-referential encoding focus and stimulus emotionality

In episodic memory, the old/new effect, the contrast of the waveforms elicited by the correctly recognized studied items and the correctly rejected novel items, has been broadly concerned. However, the contribution of self-referential encoding to the old/new effect in source memory (i.e., source-SRE), is far from clarification; further, it remains unclear whether the contribution is susceptible to the factor of stimulus emotionality. To address these issues, adopting the event-related potential (ERP) technique, this study applied words of three types of emotional valences (positive, neutral, vs. negative) in the self-focus vs. external-focus encoding tasks. In the course of the test, four ERP old/new effects were identified: (a) the familiarity- and recollection-reflected mid-frontal effect (FN400) and late positive component (LPC) were both independent of source-SRE and stimulus emotionality; (b) the reconstruction-driven late posterior negativity (LPN) exhibited an adverse pattern of source-SRE and was susceptible to the emotional valence by encoding focus; and (c) the right frontal old/new effect (RFE), reflecting post-retrieval process, exhibited a source-SRE in emotional words. These effects provide compelling evidence for the influences of both stimulus valence and encoding focus on SRE in source memory, especially during the late processes. Further directions considering more perspectives are put forward.

Development of self-referential effect on memory recollection

Information learned in relation to oneself is typically better remembered, termed the self-reference effect (SRE). This study aimed to elucidate the developmental trajectory of the SRE in recollection and source memory from mid-childhood to young adulthood. In 2018-2019 in Baltimore, Maryland, 136 seven- to thirty-year-olds (77 female; approximately 80% White, 15% Asian American, 5% Black) viewed objects on one of two backgrounds and answered a self-referential or semantic question for each. A recognition test probed memory for objects and source details (inherent: question type; peripheral: background image). SRE increased with age for detailed recollection (r = .189), but not familiarity, and extended to inherent source memory. This suggests that self-referencing promotes richer memory in children and develops into young adulthood.

Multiple producible cues do not aid face-name memory: A reverse production effect

Are there effective mechanisms that can be used to remember someone's name? The production effect is a phenomenon that exemplifies memory's robust benefit for studied words or phrases that have been spoken out loud, as opposed to only hearing or seeing them. However, this robust effect has not yet been identified for face-name pairings. The present study seeks to examine the boundary conditions of the production effect in face-name pairings by incorporating the additional cue of valenced adjectives. Participants were presented with facial images and a sentence stating the name and a description of the individual. Sentences were learned in one of four ways: saying the sentence out loud, reading it silently, reading it while hearing it, or only listening to the sentence presented while viewing the face. Memory for the face, name, and adjective combinations were tested using various types of cues: face only (Experiment 1a), or face and name or adjective (Experiment 1b & Experiment 2). Results replicate the lack of a production effect for face-name memory, and instead support a reverse effect for such stimuli. These findings indicate the unique processing of faces and highlight boundary conditions of the production effect.

Memory for emotional images across sleep versus wake in school-aged children

Sleep is important for emotional well-being, memory, and development in children. Regarding memory, sleep has been shown to advantage accuracy for declarative tasks but not procedural tasks. There is some evidence to suggest that sleep provides a relatively greater benefit for memory of negative emotional versus neutral images. However, the extent to which sleep benefits emotionally positive memories in children is not clear. This study assessed memory after nocturnal sleep versus daytime wake in a within-person design involving a sample of 40 children aged 7 to 14 years (M = 10.6 ± 1.9 years; 18 boys and 22 girls) for images of negative, neutral, and positive valences. Results show that after accounting for response time, memory accuracy overall was greater after sleep compared with equivalent time of wake and memory accuracy was greatest for positive images compared with both negative and neutral images. However, there was no difference between memory for negative images and that for neutral images in children, and there was no condition by valence interaction. Sleep characteristics as recorded using actigraphy, diary, and parent report were not predictive of memory performance after sleep when correcting for multiple comparisons. Overall, the results suggest that sleep may benefit memory in otherwise healthy children but that despite a bias toward memory for positive items over both negative and neutral items, there is not a relatively greater benefit for emotional versus neutral memory consolidation across sleep periods compared with wake periods.

When non-salient information becomes salient in conversational memory: Collaboration shapes the effects of emotion and self-production

People's memory of what was said and who said what during dialogue plays a central role in mutual comprehension and subsequent adaptation. This article outlines that well-established effects in conversational memory such as the self-production and the emotional effects actually depend on the nature of the interaction. We specifically focus on the impact of the collaborative nature of the interaction, comparing participants' conversational memory in non-collaborative and collaborative interactive settings involving interactions between two people (i.e., dialogue). The findings reveal that the amplitude of these conversational memory effects depends on the collaborative vs. non-collaborative nature of the interaction. The effects are attenuated when people have the opportunity to collaborate because information that remained non-salient in the non-collaborative condition (neutral and partner-produced words) became salient in the collaborative condition to a level similar to otherwise salient information (emotional and self-produced words). We highlight the importance of these findings in the study of dialogue and conversational memory.

Is there a self-positivity bias for destination memory? Behavioral and ERP evidence

Despite extensive existing research concerning source memory (i.e., memory for what has been said, given, or done to us by whom) during social interaction, destination memory (i.e., memory for what we have said, given, or done to whom) remains to be explored. Furthermore, although destination memory is believed to involve a self-reference process, it remains unclear whether such a process is sufficient to trigger a self-positivity bias. To address these issues, we combined the destination memory paradigm with the social dilemma game to compare destination memory for cooperation and cheating. Both behavioral performance and the neural index of successful encoding, the Dm (difference due to memory) effect, were concerned. Behaviorally, destination memory for cooperative, cheating, and neutral behaviors decreased successively. For neural activities, the pre-400 ms Dm effects during 200-400 ms were non-significant under any condition. In the latency windows of 400-800 ms and 800-1000 ms, the post-400 ms Dm effects were reliably observed for both cooperative and cheating behaviors and were statistically comparable between the two behavior types, but the effect was not obtained for neutral behaviors. These data suggest a self-positivity bias in the behavioral performance but not in the encoding-related Dm effects of destination memory.

Interactions of Emotion and Self-reference in Source Memory: An ERP Study

The way emotional information is encoded (e.g., deciding whether it is self-related or not) has been found to affect source memory. However, few studies have addressed how the emotional quality and self-referential properties of a stimulus interactively modulate brain responses during stimulus encoding and source memory recognition. In the current study, 22 participants completed five study-test cycles with negative, neutral, and positive words encoded in self-referential versus non-self-referential conditions, while event-related potentials of the electroencephalogram were recorded. An advantage of self-referential processing in source memory performance, reflected in increased recognition accuracy, was shown for neutral and positive words. At the electrophysiological level, self-referential words elicited increased amplitudes in later processing stages during encoding (700-1,200 ms) and were associated with the emergence of old/new effects in the 300-500 ms latency window linked to familiarity effects. In the 500-800 ms latency window, old/new effects emerged for all valence conditions except for negative words studied in the non-self-referential condition. Negative self-referential words also elicited a greater mobilization of post-retrieval monitoring processes, reflected in an enhanced mean amplitude in the 800-1,200 ms latency window. Together, the current findings suggest that valence and self-reference interactively modulate source memory. Specifically, negative self-related information is more likely to interfere with the recollection of source memory features.

Pure-list production improves item recognition and sometimes also improves source memory

Relative to reading silently, reading words aloud (a type of "production") typically enhances item recognition, even when production is manipulated between groups using pure lists. We investigated whether pure-list production also enhances memory for various item details (i.e., source memory). Screen side (Experiment 1), font size (Experiment 2), or reading versus generating from anagrams (Experiments 3-4) were the sources varied within-subject, and aloud versus silent reading was varied across groups. Thus, the manipulation of source was apparent to participants, whereas the manipulation of production was not. Traditional measures and multinomial modeling established that the aloud groups generally showed improved item recognition-and showed improved source memory when steps were taken to enhance the salience of the source manipulation (Experiment 4). In summary, reading an entire list of items improves item recognition and can also improve memory for some types of source details.

Is internal source memory recognition modulated by emotional encoding contexts?

The influence of emotion on memory has been mainly examined by manipulating the emotional valence and/or arousal of critical items. Few studies probed how emotional information presented during the encoding of critical neutral items modulates memory recognition, particularly when considering source memory features. In this study, we specified the role of emotional encoding contexts in internal source memory performance (discrimination between encoding tasks) using a mixed (Experiment 1) and a blocked design (Experiment 2). During the study phase, participants were required to evaluate a set of neutral words, using either a self-referential or a semantic (common judgment) encoding strategy. Prior and concomitantly with each word, negative, neutral or positive pictures were presented in the background. The beneficial effect of self-referential encoding was observed for both item and internal source memory in both experiments. Remarkably, item and internal source memory recognition was not modulated by emotion, even though a secondary analysis indicated that the consistent exposure to negative (vs. positive) information led to worse source memory performance. These findings suggest that internal source memory of neutral items is not always affected by changing or repetitive emotional encoding contexts.