Emotional memory: No source memory without old-new recognition.

Previous research has shown a source memory advantage for faces presented in negative contexts. As yet it remains unclear whether participants remember the specific type of context in which the faces were presented or whether they can only remember that the face was associated with negative valence. In the present study, participants saw faces together with descriptions of two different types of negative behaviour and neutral behaviour. In Experiment 1, we examined whether the participants were able to discriminate between two types of other-relevant negative context information (cheating and disgusting behaviour) in a source memory test. In Experiment 2, we assessed source memory for other-relevant negative (threatening) context information (other-aggressive behaviour) and self-relevant negative context information (self-aggressive behaviour). A multinomial source memory model was used to separately assess partial source memory for the negative valence of the behaviour and specific source memory for the particular type of negative context the face was associated with. In Experiment 1, source memory was specific for the particular type of negative context presented (i.e., cheating or disgusting behaviour). Experiment 2 showed that source memory for other-relevant negative information was more specific than source memory for self-relevant information. Thus, emotional source memory may vary in specificity depending on the degree to which the negative emotional context is perceived as threatening.

Fronto-limbic brain activity during sleep is believed to support the consolidation of emotional memories in healthy adults. Attention deficit-hyperactivity disorder (ADHD) is accompanied by emotional deficits coincidently caused by dysfunctional interplay of fronto-limbic circuits. This study aimed to examine the role of sleep in the consolidation of emotional memory in ADHD in the context of healthy development. 16 children with ADHD, 16 healthy children, and 20 healthy adults participated in this study. Participants completed an emotional picture recognition paradigm in sleep and wake control conditions. Each condition had an immediate (baseline) and delayed (target) retrieval session. The emotional memory bias was baseline–corrected, and groups were compared in terms of sleep-dependent memory consolidation (sleep vs. wake). We observed an increased sleep-dependent emotional memory bias in healthy children compared to children with ADHD and healthy adults. Frontal oscillatory EEG activity (slow oscillations, theta) during sleep correlated negatively with emotional memory performance in children with ADHD. When combining data of healthy children and adults, correlation coefficients were positive and differed from those in children with ADHD. Since children displayed a higher frontal EEG activity than adults these data indicate a decline in sleep-related consolidation of emotional memory in healthy development. In addition, it is suggested that deficits in sleep-related selection between emotional and non-emotional memories in ADHD exacerbate emotional problems during daytime as they are often reported in ADHD.

Individuals in preclinical and clinical stages of Huntington's disease (HD) demonstrate impairments in olfactory functioning. In addition, HD patients are impaired in source memory for verbal stimuli. A task combining both source and odor memory may be particularly sensitive to early changes in HD. The present study examined source and item memory for olfactory and visual stimuli in 10 individuals with HD, 10 asymptomatic HD gene carriers, 8 nongene carriers who had a parent with HD, and 20 normal controls. During the study phase, a male and a female experimenter (sources) presented odors and objects to the participant in an alternating sequence. To assess item memory, a stimulus from the study phase (target) and a novel stimulus (distractor) were presented, and the participant was asked to choose the target. To assess source memory, the experimenter presented a stimulus and asked whether the male or female experimenter had previously presented the stimulus. Results indicate that source memory for both visual and olfactory stimuli was impaired in HD patients compared to normal controls. In asymptomatic gene carriers, however, source memory for olfactory stimuli, but not visual stimuli, was more impaired than in nongene carriers and normal controls. Furthermore, gene carriers and HD patients showed a similar degree of impairment in source memory for olfactory stimuli. The only significant impairment found in item memory was for olfactory stimuli in HD patients. These results suggest that source memory for olfactory stimuli may be particularly sensitive to neuropathological changes in preclinical stages of HD.

Introduction Remembering relationships between items (information) and the contexts (sources) in which they are framed is crucial for everyday functioning. Total sleep deprivation (TSD) impairs this ability, with evidence suggesting that TSD affects source memory even when items are remembered. Source memory deficits imply problems with associative memory, which relies on hippocampal functioning, known to be altered by TSD. Serotonin is highly expressed in the hippocampus, is influenced by TSD, and may be part of a mechanism by which TSD degrades source memory. We investigated the association between 5-HTTLPR, a functional length polymorphism of the human serotonin transporter gene (SLC6A4), and item and source memory during TSD. Methods N=34 healthy adults (ages 27.3±4.9y; 18 female) participated in a 4-day/3-night laboratory TSD study. Participants underwent 38h TSD, preceded and followed by 10h sleep opportunities. At baseline and 24h later during TSD, they completed an item/source memory task. Participants listened to a list of 60 words each presented by a male or female speaker (study phase). They were then tested for recognition of the words (items) out of 60 old and 60 new words presented visually, and were asked to identify the corresponding speakers (sources, male or female). Results The genotype distribution was in Hardy-Weinberg equilibrium (P=0.34), with 35.3% long/long, 41.2% long/short, 23.5% short/short. Mixed-effects ANOVA showed a significant adverse effect of TSD for both item recognition (P< 0.001) and source recognition (P< 0.001), where TSD degraded source memory even when item recognition was accurate. There were no 5-HTTLPR genotype effects on item memory. However, there was a significant main effect for genotype on source memory (P=0.019), and a genotype by TSD interaction (P=0.018). For accurately recognized items, source memory was largely preserved for the short/short genotype but impaired for carriers of the long allele, and especially the long/long genotype. Conclusion 5-HTTLPR genotype predicted source memory deficits from TSD, distinct from item memory deficits unaffected by genotype, which confirms that item and source memory deficits due to TSD are dissociable. Furthermore, TSD’s impact on binding of items and sources in memory may be mediated by hippocampal serotonin. Support (if any) NIH R21CA167691, WSU Anthony Marchionne and Foundry10 Bridge fellowships

Abstract. The investigation of source monitoring (SM) as a special faculty of episodic memory has gained much attention in recent years. However, several measures of source memory have been used in research practice that show empirical and theoretical shortcomings: First, they often confound various cognitive processes like source memory, item memory and response bias, and second, they do not do justice to the multitude of processes involved in SM according to the framework of Johnson, Hashtroudi, and Lindsay (1993) . We therefore review model-based measurement approaches, focusing on multinomial models, and we distinguish between theorizing about source memory and the pragmatics of source memory measurement as two partly separate goals of research. Whereas signal detection models seem to be more adequate theories of the underlying source monitoring process, multinomial models have some pragmatic advantages that nevertheless recommend them as viable measurement tools.

The existence of a functional-anatomic dissociation for retrieving item versus contextual information within subregions of the medial temporal lobe (MTL) is currently under debate. We used a spatial source memory paradigm during event-related functional magnetic resonance imaging to investigate this issue. At study, abstract shapes were presented to the left or right of fixation. During test, old and new shapes were presented at fixation. Participants responded whether each shape had been previously presented on the “left,” the “right,” or was “new.” Activity associated with contextual memory (i.e., source memory) was isolated by contrasting accurate versus inaccurate memory for spatial location. Item-memory-related activity was isolated by contrasting accurate item recognition without contextual memory with forgotten items. Source memory was associated with activity in the hippocampus and parahippocampal cortex. Although item memory was not associated with unique MTL activity at our original threshold, a region-of-interest (ROI) analysis revealed item-memory-related activity in the perirhinal cortex. Furthermore, a functional-anatomic dissociation within the parietal cortex for retrieving item and contextual information was not found in any of three ROIs. These results support the hypothesis that specific subregions in the MTL are associated with item memory and memory for context.

The present study examined the role of enactment in source memory in a cognitively impaired population. As seen in healthy older adults, it was predicted that source memory in people with mild cognitive impairment due to Alzheimer's disease (MCI-AD) would benefit from the self-reference aspect of enactment. Seventeen participants with MCI-AD and 18 controls worked in small groups to pack a picnic basket and suitcase and were later tested for their source memory for each item. For item memory, self-referencing improved corrected recognition scores for both MCI-AD and control participants. The MCI-AD group did not demonstrate the same benefit as controls in correct source memory for self-related items. However, those with MCI-AD were relatively less likely to misattribute new items to the self and more likely to misattribute new items to others when committing errors, compared with controls. The enactment effect and self-referencing did not enhance accurate source memory more than other referencing for patients with MCI-AD. However, people with MCI-AD benefited in item memory and source memory, being less likely to falsely claim new items as their own, indicating some self-reference benefit occurs for people with MCI-AD.

The attention-elaboration hypothesis of memory for schematically unexpected information predicts better source memory for unexpected than expected sources. In three source-monitoring experiments, the authors tested the occurrence of an inconsistency effect in source memory. Participants were presented with items that were schematically either very expected or very unexpected for their source. Multinomial processing tree models were used to separate source memory, item memory, and guessing bias. Results show an inconsistency effect in source memory accompanied by a compensatory schema-consistent guessing bias when expectancy strength is high, that is, when items are very expected or very unexpected for their source.

Modulatory effects of stress on reactivated emotional memories

Effect of the congruity of emotional contexts at encoding on source memory: Evidence from ERPs

There are many discussions about whether emotions affect general learning abilities, especially the memory part.There are several pieces of research have successfully proved that emotional memories contain more accurate details than nonemotional memories do, especially negative emotions.This paper focuses more on whether positive emotion can successfully increase people's memory accuracy on verbal memories.This paper responds to this question by proposing a method of manipulating emotion and testing people's memory accuracy under certain emotions.This paper gives evidence suggesting that positive emotion wouldn't increase people's memory accuracy as we thought.There is only a slight difference in memory accuracy between positively emotionally stimulated people and neutrally emotionally stimulated people, and we can't prove that emotional cues help to increase memory retrieving accuracy.

A functional gradient has been proposed across the medial temporal lobes (MTL) such that the anterior MTL is thought to support processing of individual items (e.g., item memory and complex object perception), whereas the posterior MTL is thought to support item-context retrieval (e.g., source memory). Whereas functional imaging studies have provided evidence supporting this anatomical organization, results from structural analyses remain inconclusive. The current study examined the relationship between volume of MTL regions of interest (ROIs), and performance on a source memory task and a fine-grain complex object perception task, in healthy young adults (mean age = 21.5, range = 18-29). Using a semiautomated procedure, we segmented the parahippocampal and perirhinal cortices (PHC, PRC), posteromedial and anterolateral entorhinal cortices (pmERC, alERC), and posterior and anterior hippocampus (postHC, antHC) on high-resolution T2-weighted MRIs. Regional volumes were computed as proportions of intracranial volume, and as posterior-anterior volumetric ratios (PHC:PRC, pmERC:alERC, postHC:antHC). Partial-least squares regressions were applied to predict source and item memory, and perceptual discrimination accuracy, based on ROI and ratio volumes. In our ROI regressions, we found that postHC volume was positively correlated with a latent factor predicting source memory, and PRC and antHC volumes were negatively correlated to this latent factor. In our ratio regressions, we observed an effect relating the posterior-anterior distribution of gray matter across the MTL with source memory. Our results demonstrate differential associations between anterior and posterior MTL and source memory performance. Findings from this study highlight the importance of considering patterns of structure-behavior associations in the neurobiology of episodic memory.

Negative emotion elicited in high school students enhances consolidation of item memory, but not source memory.

Females’ superiority in item memory, but not source memory for neutral and emotional Chinese words

Affective states are closely linked to attention to internal aspects of the self (i.e., self-focused attention). We investigated how self-focused attention induced by emotional experiences affects memory for subsequently presented information. Prior to incidental encoding of affectively neutral target words, participants were induced to feel shame or anger through autobiographical recall (vs. no emotion-induction control condition). Memory for words (item memory) and their associated contextual features (source memory) were subsequently assessed. Self-focused attention, measured by the private self-consciousness scale, was highest in the shame condition, followed by the anger and then control conditions. Item memory was significantly impaired in the shame condition compared to both the anger and control conditions, and self-focused attention negatively mediated the effect of emotion condition on memory performance. Source memory did not significantly differ across the emotion conditions, and we discuss possible factors contributing to this null finding. Our findings suggest that emotion-induced self-focused attention may reduce attentional resources available for encoding task-relevant external information.