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Motivational and emotional influences on memory have been studied extensively; however, despite the link between these constructs, they have been studied in separate lines of research, with very little work examining their effects concurrently. The current study takes a novel approach to manipulate motivational and emotional influences orthogonally, and within the same task, to test their interplay on intentional memory formation. If emotion and reward motivation are tightly linked, they may rely on overlapping cognitive mechanisms, thus we would not expect emotion and reward to interact in memory. Alternatively, they could be distinct constructs and therefore would boost memory when both are included in the same experimental trial, above and beyond additive effects. To test these competing predictions, in Experiment 1, participants (n = 180) completed an old/new recognition memory task with emotional (negative, positive) and neutral words intentionally encoded with high or low reward anticipation cues. In Experiment 2, participants (n = 159) encoded emotional and neutral words with a high or low reward cue, but memory was tested with free recall using study-test blocks. The findings from both experiments converged. There were main effects of emotion and reward in generally hypothesized directions, but no evidence of an interaction between these factors. This is in line with the prediction that emotion and reward motivation are similar constructs. Their combination within a trial does not boost memory above and beyond either of these factors alone perhaps indicating these constructs have similar cognitive mechanisms.
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OBJECTIVES: Older adults show memory benefits for self-relevant and emotional content, but there are individual differences in this effect. It has been debated whether processing of self-relevant and emotional information relies on similar processes to one another. We examined whether variation in frontal lobe (FL) function among older adults related similarly to the processing of self-relevant information as it did to emotional information, or whether these relations diverged. METHODS: While undergoing fMRI, participants (ages 60-88) viewed positive, negative, and neutral objects, and imagined placing those objects in either their home or a stranger's home. Participants completed a surprise memory test outside of the MRI. In a separate session, a cognitive battery was collected and composite scores measuring FL and medial temporal lobe function were computed and related to the behavioral memory performance and the neural engagement during fMRI. RESULTS: Behaviorally, FL function related to memory for self-relevant, but not emotional content. Older adults with higher FL function demonstrated reduced self-bias in memory performance. During the processing of self-relevant stimuli, independent of emotion, levels of activity in the middle frontal gyrus showed positive associations with FL function. This relationship was not driven by compensatory activity or disruptions to nonself-relevant neutral content. DISCUSSION: These findings point to divergence in the cognitive functions relating to memory enhancements for self- and emotional-relevance. The results further suggest self-relevance as a mnemonic device for older adults, especially in those with lower FL function.
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Mapeo Encefálico , Individualidad , Humanos , Anciano , Emociones , Memoria , Lóbulo Frontal/diagnóstico por imagen , Imagen por Resonancia MagnéticaRESUMEN
Remembering and forgetting are both important processes of a healthy memory system, but both processes can show age-related decline. Reward anticipation is effective at improving remembering in both younger and older adults, but little is known about the effects of incentives on forgetting. In four online experiments, we examined whether reward motivation modulates intentional remembering and forgetting in younger and older adults, and systematically varied the presentation of reward cues during encoding to test whether the temporal dynamics of reward anticipation are important for directed forgetting performance. Both age groups showed directed forgetting effects such that participants remembered more items they were instructed to remember than instructed to forget, but across experiments, we found no evidence that reward incentives improved forgetting in either age group. Younger adults consistently exhibited reward-modulated memory across experiments and varying the timing of the reward cue had little impact on performance. Older adults displayed inconsistent effects of reward on memory, only when reward anticipation was elicited closer to the middle of the experimental trial did it enhance memory in this task. Overall, the findings from the current set of experiments indicate that reward anticipation improved memory, but not forgetting, and most consistently for younger adults, compared to older adults. Further, older adults' cognitive performance may be more sensitive to the placement and timing of reward anticipation in the experimental trial perhaps due to the time course of reward anticipation and interactions with the hippocampus that may show age-related change. (PsycInfo Database Record (c) 2023 APA, all rights reserved).
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Envejecimiento , Motivación , Humanos , Anciano , Recuerdo Mental , Señales (Psicología) , RecompensaRESUMEN
Many individuals have experienced a multitude of chronic stressors and diminished psychological functioning during COVID-19. The current study examined whether biases towards positive social media or positive autobiographical memories was related to increases in psychological functioning during COVID-19. Participants were 1071 adults (Mage = 46.31; 58% female; 78% White) recruited from MTurk. Participants reported on their social media consumption and autobiographical recall, positive and negative affect, and dysphoria symptoms. Results indicated that, at the first assessment collected in the spring and summer of 2020, positively biased social media consumption was cross-sectionally related to higher levels of positive affect, and positively biased autobiographical recall was cross-sectionally related to lower levels of negative affect and dysphoria symptoms. Sensitivity analyses examined cross-sectional relations from a second assessment collected in fall 2020, and prospective cross-lagged analyses. The findings point to potential psychological benefits of positive biases during chronic stressors.
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COVID-19 , Trastorno Depresivo Mayor , Adulto , Humanos , Femenino , Masculino , Pandemias , Estudios Transversales , Estudios ProspectivosRESUMEN
OBJECTIVES: Research has demonstrated links between autobiographical memory retrieval and hazardous substance use. However, limited work has examined relations between positive autobiographical memories and hazardous substance use, as well as moderating factors influencing these relations. Thus, we examined the potential moderating roles of negative and positive emotion dysregulation in the relations between count of retrieved positive memories and hazardous substance use (alcohol and drug use separately). METHODS: Participants were 333 trauma-exposed students (Mage = 21.05; 85.9% women) who completed self-report measures assessing positive memory count, hazardous alcohol and drug use, negative emotion dysregulation, and positive emotion dysregulation. RESULTS: Positive emotion dysregulation significantly moderated the association between positive memory count and hazardous alcohol use (b = 0.04, 95% confidence interval [CI] [0.01, 0.06], p = 0.019), as well as the association between positive memory count and hazardous drug use (b = 0.02, 95% CI [0.01, 0.03], p = 0.002). Individuals with more positive emotion dysregulation had stronger associations between increases in positive memory count and increased hazardous substance use. CONCLUSION: Findings indicate that trauma-exposed individuals who retrieve more positive memories and experience difficulties regulating positive emotions report greater hazardous substance use. Positive emotion dysregulation may be an important target for memory-based interventions among trauma-exposed individuals who report hazardous substance use.
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Trastornos Relacionados con Sustancias , Humanos , Femenino , Adulto Joven , Adulto , Masculino , Trastornos Relacionados con Sustancias/epidemiología , Trastornos Relacionados con Sustancias/psicología , Autoinforme , Cognición , Emociones , Sustancias PeligrosasRESUMEN
Posttraumatic growth (PTG) has captivated the attention of clinicians and researchers over the past three decades. However, accumulating evidence suggests that individuals' self-reports of PTG may be cognitively biased. In the current systematic review and meta-analysis, we aimed to investigate the relation between cognitive biases and perceived PTG. In line with existing theory on cognitive biases that may lead to illusory perceived PTG, we examined the following cognitive biases: defensiveness, memory bias, downward comparison bias, social desirability bias, positive attention bias, and growth beliefs. Forty-seven studies met criteria for inclusion in this review and 66 separate effects were coded for meta-analyses. Results indicated that cognitive biases were related to perceived PTG, with variation by type of cognitive bias. Moderator analyses revealed that downward comparison bias, positive attention bias, and growth beliefs exhibited stronger relations with perceived PTG than did defensiveness, memory bias, and social desirability bias. Further, subgroup analyses explored effects by type of cognitive bias and characteristics of cognitive bias measurements. The current study suggests that cognitive biases may have a role in individuals' perceptions of their PTG. This contributes to theory on the origins of illusory perceptions of PTG and provides direction for improvements to the measurement of PTG and clinical approaches to PTG.
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Sesgo Atencional , Crecimiento Psicológico Postraumático , Trastornos por Estrés Postraumático , Adaptación Psicológica , Sesgo , Cognición , HumanosRESUMEN
As we age, we show increased attention and memory for positive versus negative information, and a key event-related potential (ERP) marker of emotion processing, the late positive potential (LPP), is sensitive to these changes. In young adults the emotion effect on the LPP is also quite sensitive to the self-relevance of stimuli. Here we investigated whether the shift toward positive stimuli with age would be magnified by self-relevance. Participants read 2-sentence scenarios that were either self-relevant or non-self-relevant with a neutral, positive, or negative critical word in the second sentence. The LPP was largest for self-relevant negative information in young adults, with no significant effects of emotion for non-self-relevant scenarios. In contrast, older adults showed a smaller negativity bias, and the effect of emotion was not modulated by self-relevance. The 3-way interaction of age, emotion, and self-relevance suggests that the presence of self-relevant stimuli may reduce or inhibit effects of emotion for non-self-relevant stimuli on the LPP in young adults, but that older adults do not show this effect to the same extent.
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Envejecimiento/psicología , Emociones/fisiología , Potenciales Evocados/fisiología , Autoestimulación/fisiología , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Atención , Femenino , Humanos , Masculino , Memoria , Persona de Mediana Edad , Adulto JovenRESUMEN
An important feature of the memory system is the ability to forget, but aging is associated with declines in the ability to intentionally forget potentially due to declines in cognitive control. Despite cognitive deficits, older adults are sensitive to affective manipulations, such as reward motivation, and reward anticipation can improve older adults' memory performance. The goal of the current studies was to examine the effect of reward motivation on directed remembering and forgetting. Participants were healthy CloudResearch/Turk Prime workers aged 18-35 and 60-85. In Experiment 1, we conducted a typical item-method directed forgetting task using neutral words presented one at a time followed by a to-be-remembered (TBR) or to-be-forgotten (TBF) cue. A recognition memory test followed that included all words from the encoding task, as well as new words. We replicated prior findings of better memory for TBR compared to TBF items, but not typical age-related differences in recognition of TBF items. In Experiments 2-4, we repeated this paradigm except that in the second block of trials, each word was presented with a high ($0.75) or low ($0.01) reward cue indicating the value that could be earned if the item was successfully Remembered or Forgotten (depending on cue). During recognition, correct responses to target items (both TBR and TBF) resulted in the associated reward, but incorrect "old" responses resulted in a loss of $0.50. In three experiments, high rewards led to better memory for younger and older adults compared to low rewards, regardless of the directed cue to remember or forget the word. In Experiments 3 and 4, older adults showed typical deficits in directed forgetting, but this was across reward conditions. For older adults, there was no evidence that including reward motivation improved cognitive control abilities as high value reward anticipation did not improve directed forgetting. Instead, in line with hypotheses, high compared to low value reward anticipation leads to engagement of processes that result in better memory regardless of the TBR or TBF cue, and reward anticipation bolsters memory in a relatively automatic, rather than strategic, fashion that overrides one's ability to cognitively control encoding processes.
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Reward-motivated memory has been studied extensively in psychology and neuroscience. Many recognition studies follow the same type of paradigm: stimuli are cued at encoding with high or low reward values which indicate the amount the stimulus is worth if successfully recognized on a subsequent memory test. Each incorrect endorsement of a lure at retrieval is penalized with an arbitrary value between the high and low reward value, resulting in a single false alarm rate. Studies employing this type of paradigm have reported higher hit rates for high value items compared to low value items, but generally hit rate is the only measure of memory that is reported as a function of reward value. It is currently not clear what aspects of the experimental design lead to these memory effects, and other measures, like discriminability and response bias, cannot be properly calculated when there is only a single false alarm rate, but we hypothesize that these are also susceptible to motivational manipulations. To test how reward anticipation might influence memory and response bias in this type of task, we created a novel paradigm that allowed us to calculate both by associating rewards with categories (indoor vs. outdoor scenes), thus calculating separate false alarm rate as well as hit rate at each level of reward. We report results of three experiments that varied rewards and penalties for correct and error responses for the category items. In two experiments, we replicated prior findings of higher hit rates for high compared to low reward items, but consistently across three experiments, when d' was calculated, we found no difference in memory discriminability as a function of reward. Further, Experiment 1 we found that response bias was more conservative for low reward items: participants were more likely to endorse a 'new' response to low compared to high reward items. This effect was significantly reduced in Experiment 2 and eliminated in Experiment 3 when the reward-penalty structure was manipulated to reduce bias. Our findings reveal that reward motivation can influence decisional biases thought to be independent of memory processes. The amount of the reward value for correct responses and the amount of the penalty for incorrect responses should be considered when designing experimental paradigms to study motivation-cognition interactions.
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Motivación , Recompensa , Señales (Psicología) , Humanos , Memoria , Reconocimiento en PsicologíaRESUMEN
Emotion and self-referential information can both enhance memory, but whether they do so via common mechanisms across the adult lifespan remains underexplored. To address this gap, the current study directly compared, within the same fMRI paradigm, the encoding of emotionally salient and self-referential information in older adults and younger adults. Behavioral results replicated the typical patterns of better memory for emotional than neutral information and for self-referential than non-self-referential materials; these memory enhancements were present for younger and older adults. In neural activity, young and older adults showed similar modulation by emotion, but there were substantial age differences in the way self-referential processing affected neural recruitment. Contrary to our hypothesis, we found little evidence for overlap in the neural mechanisms engaged for emotional and self-referential processing. These results reveal that-just as in cognitive domains-older adults can show similar performance to younger adults in socioemotional domains even though the two age groups engage distinct neural mechanisms. These findings demonstrate the need for future research delving into the neural mechanisms supporting older adults' memory benefits for socioemotional material.
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Cognición/fisiología , Emociones/fisiología , Memoria/fisiología , Anciano , Envejecimiento/fisiología , Femenino , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Adulto JovenRESUMEN
Both younger and older adults prioritize reward-associated stimuli in memory, but there has been little research on possible age differences in the neural mechanisms mediating this effect. In the present study, we examine neural activation and functional connectivity in healthy younger and older adults to test the hypothesis that older adults would engage prefrontal regions to a greater extent in the service of reward-enhanced memory. While undergoing MRI, target stimuli were presented after high- or low-reward cues. The cues indicated the reward value for successfully recognizing the stimulus on a memory test 24 hours later. We replicated prior findings that both older and younger adults had better memory for high- compared to low-reward stimuli. Critically, in older but not younger adults, this enhanced subsequent memory for high-reward items was supported by greater connectivity between the caudate and bilateral inferior frontal gyrus. The findings add to the growing literature on motivation-cognition interactions in healthy aging and provide novel findings of the neural underpinnings of reward-motivated encoding.
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Envejecimiento/psicología , Núcleo Caudado/fisiología , Función Ejecutiva/fisiología , Memoria/fisiología , Vías Nerviosas/fisiología , Corteza Prefrontal/fisiología , Recompensa , Adulto , Anciano , Cognición/fisiología , Señales (Psicología) , Femenino , Humanos , Masculino , Motivación , Adulto JovenRESUMEN
Memory retrieval is thought to involve the reactivation of encoding processes. Previous fMRI work has indicated that reactivation processes are modulated by the residual effects of the prior emotional encoding context; different spatial patterns emerge during retrieval of memories previously associated with negative compared with positive or neutral context. Other research suggests that event-related potential (ERP) indicators of memory retrieval processes, like the left parietal old/new effect, can also be modulated by emotional context, but the spatial distribution and temporal dynamics of these effects are unclear. In the current study, we examined "when" emotion affects recognition memory and whether that timing reflects processes that come before and may guide successful retrieval or postrecollection recovery of emotional episodic detail. While recording EEG, participants (n = 25) viewed neutral words paired with negative, positive, or neutral pictures during encoding, followed by a recognition test for the words. Analyses focused on ERPs during the recognition test. In line with prior ERP studies, we found an early positive-going parietally distributed effect starting around 200 msec after retrieval-cue onset. This effect emerged for words that had been encoded in an emotional compared with neutral context (no valence differences), before the general old/new effect. This emotion-dependent effect occurred in an early time window, suggesting that emotion-related reactivation is a precursor to successful recognition.
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Señales (Psicología) , Emociones/fisiología , Potenciales Evocados/fisiología , Memoria Episódica , Recuerdo Mental/fisiología , Lóbulo Parietal/fisiología , Reconocimiento en Psicología/fisiología , Adulto , Asociación , Electroencefalografía , Femenino , Humanos , Lenguaje , Masculino , Reconocimiento Visual de Modelos/fisiología , Factores de Tiempo , Adulto JovenRESUMEN
IgE is secreted by plasma cells (PCs) and is central to allergic disease. Using an ex vivo tonsil B cell culture system, which mimics the Th2 responses in vivo, we have recently characterized the development pathway of human IgE-expressing PCs. In this system, as in mice, we reported the predisposition of IgE-expressing B cells to differentiate into PCs. To gain a comprehensive understanding of the molecular events involved in the differentiation of human IgE+ B cells into PCs we have used the Illumina HumanHT-12 v4 Expression BeadChip array to analyse the gene expression profile of ex vivo generated human IgE+ B cells at various stages of their differentiation into PCs. We also compared the transcription profiles of IgE+ and IgG1+ cells to discover isotype-specific patterns. Comparisons of IgE+ and IgG1+ cell transcriptional profiles revealed molecular signatures specific for IgE+ cells, which diverge from their IgG1+ cell counterparts upon differentiation into PCs. At the germinal center (GC) stage of development, unlike in some mouse studies of IgE biology, we observed similar rates of apoptosis and no significant differences in the expression of apoptosis-associated genes between the IgE+ and IgG1+ B cells. We identified a gene interaction network associated with early growth response 1 (EGR1) that, together with the up-regulated IRF4, may account for the predisposition of IgE+ B cells to differentiate into PCs. However, despite their swifter rates of PC differentiation, the transcription profile of IgE+ PCs is more closely related to IgE+ and IgG1+ plasmablasts (PBs) than to IgG1+ PCs, suggesting that the terminal differentiation of IgE+ cells is impeded. We also show that IgE+ PCs have increased levels of apoptosis suggesting that the IgE+ PCs generated in our in vitro tonsil B cell cultures, as in mice, are short-lived. We identified gene regulatory networks as well as cell cycle and apoptosis signatures that may explain the diverging PC differentiation programme of these cells. Overall, our study provides a detailed analysis of the transcriptional pathways underlying the differentiation of human IgE-expressing B cells and points to molecular signatures that regulate IgE+ PC differentiation and function.
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Diferenciación Celular/genética , Inmunoglobulina E/metabolismo , Células Plasmáticas/metabolismo , Transcriptoma/genética , Apoptosis/genética , Células Cultivadas , Proteína 1 de la Respuesta de Crecimiento Precoz/genética , Regulación de la Expresión Génica , Redes Reguladoras de Genes , Centro Germinal/inmunología , Humanos , Hipersensibilidad/metabolismo , Inmunoglobulina G/metabolismo , Factores Reguladores del Interferón/genética , Tonsila Palatina/patología , FenotipoRESUMEN
Affective processing is one domain that remains relatively intact in healthy aging. Investigations into the neural responses associated with reward anticipation have revealed that older and younger adults recruit the same midbrain reward regions, but other evidence suggests this recruitment may differ depending on the valence (gain, loss) of the incentive cue. The goal of the current study was to examine functional covariance during gain and loss feedback in younger and healthy older adults. A group of 15 older adults (mean age = 68.5) and 16 younger adults (mean age = 25.4) completed a revised Monetary Incentive Delay task (rMID; Knutson, Westdorp, Kaiser, & Hommer, 2000) while in the fMRI scanner. The rMID is a reaction time task where successful performance, either gaining a reward or avoiding a loss, is defined by hitting a button during the brief presentation of a visual target. Participants receive gain and loss anticipation cues before each trial and feedback after each trial with four possible outcomes: +$5.00, +0.00, -$5.00, and -$0.00. Using seed-voxel partial least squares analyses, with seed voxels in the caudate and ventromedial prefrontal cortex, whole-brain functional covariance revealed that younger and older adults engage the same network of regions to support general feedback processing. However, older adults engaged two additional networks to support processing of negative feedback, gain_miss (+0), loss_miss (-$5), and loss_hit (-0), specifically. These findings are in line with theories of a positivity effect in aging and may have implications for reward-stimulus learning and decision making following performance-contingent negative feedback.
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Encéfalo/fisiología , Retroalimentación , Adulto , Factores de Edad , Anciano , Anticipación Psicológica/fisiología , Encéfalo/diagnóstico por imagen , Femenino , Neuroimagen Funcional , Humanos , Imagen por Resonancia Magnética , Masculino , Persona de Mediana Edad , Tiempo de Reacción/fisiología , Recompensa , Adulto JovenRESUMEN
Antibodies classically bind antigens via their complementarity-determining regions, but an alternative mode of interaction involving V-domain framework regions has been observed for some B cell "superantigens." We report the crystal structure of an antibody employing both modes of interaction simultaneously and binding two antigen molecules. This human antibody from an allergic individual binds to the grass pollen allergen Phl p 7. Not only are two allergen molecules bound to each antibody fragment (Fab) but also each allergen molecule is bound by two Fabs: One epitope is recognized classically, the other in a superantigen-like manner. A single allergen molecule thus cross-links two identical Fabs, contrary to the one-antibody-one-epitope dogma, which dictates that a dimeric allergen at least is required for this to occur. Allergens trigger immediate hypersensitivity reactions by cross-linking receptor-bound IgE molecules on effector cells. We found that monomeric Phl p 7 induced degranulation of basophils sensitized solely with this monoclonal antibody expressed as an IgE, demonstrating that the dual specificity has functional consequences. The monomeric state of Phl p 7 and two structurally related allergens was confirmed by size-exclusion chromatography and multiangle laser light scattering, and the results were supported by degranulation studies with the related allergens, a second patient-derived allergen-specific antibody lacking the nonclassical binding site, and mutagenesis of the nonclassically recognized allergen epitope. The antibody dual reactivity and cross-linking mechanism not only have implications for understanding allergenicity and allergen potency but, importantly, also have broader relevance to antigen recognition by membrane Ig and cross-linking of the B cell receptor.
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Anticuerpos Monoclonales/inmunología , Antígenos de Plantas/inmunología , Proteínas de Unión al Calcio/inmunología , Epítopos/inmunología , Superantígenos/inmunología , Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/metabolismo , Especificidad de Anticuerpos/inmunología , Antígenos de Plantas/química , Antígenos de Plantas/metabolismo , Basófilos/inmunología , Basófilos/fisiología , Proteínas de Unión al Calcio/química , Proteínas de Unión al Calcio/metabolismo , Degranulación de la Célula/inmunología , Reacciones Cruzadas/inmunología , Cristalografía por Rayos X , Epítopos/química , Epítopos/metabolismo , Humanos , Inmunoglobulina E/química , Inmunoglobulina E/inmunología , Inmunoglobulina E/metabolismo , Modelos Moleculares , Unión Proteica , Conformación Proteica , Superantígenos/química , Superantígenos/metabolismoRESUMEN
A hallmark feature of episodic memory is that of "mental time travel," whereby an individual feels they have returned to a prior moment in time. Cognitive and behavioral neuroscience methods have revealed a neurobiological counterpart: Successful retrieval often is associated with reactivation of a prior brain state. We review the emerging literature on memory reactivation and recapitulation, and we describe evidence for the effects of emotion on these processes. Based on this review, we propose a new model: Negative Emotional Valence Enhances Recapitulation (NEVER). This model diverges from existing models of emotional memory in three key ways. First, it underscores the effects of emotion during retrieval. Second, it stresses the importance of sensory processing to emotional memory. Third, it emphasizes how emotional valence - whether an event is negative or positive - affects the way that information is remembered. The model specifically proposes that, as compared to positive events, negative events both trigger increased encoding of sensory detail and elicit a closer resemblance between the sensory encoding signature and the sensory retrieval signature. The model also proposes that negative valence enhances the reactivation and storage of sensory details over offline periods, leading to a greater divergence between the sensory recapitulation of negative and positive memories over time. Importantly, the model proposes that these valence-based differences occur even when events are equated for arousal, thus rendering an exclusively arousal-based theory of emotional memory insufficient. We conclude by discussing implications of the model and suggesting directions for future research to test the tenets of the model.
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Emociones/fisiología , Memoria Episódica , Recuerdo Mental/fisiología , Modelos Psicológicos , HumanosRESUMEN
Degranulation of mast cells and basophils, with release of agents of the allergic response, ensues when multivalent antigens bind to and cross-link the cells' receptor-bound IgE antibodies. A widely used commercial monoclonal IgE antibody, SPE-7 IgE from Sigma, was found to possess the radically anomalous property, termed "cytokinergic", of inducing basophil degranulation without the intervention of an antigen. We show here that the IgE monomer, freed of protein contaminants, is devoid of this activity, and that the source of the anomaly is a trace impurity, identified as a dissociation-resistant IgE trimer. Possible models for the formation of IgE trimers and the manner in which they cross-link cell surface receptors are suggested herein.
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Anticuerpos Monoclonales/química , Anticuerpos Monoclonales/inmunología , Basófilos/inmunología , Degranulación de la Célula/inmunología , Inmunoglobulina E/química , Inmunoglobulina E/inmunología , Multimerización de Proteína , Animales , Anticuerpos Monoclonales/aislamiento & purificación , Anticuerpos Monoclonales/metabolismo , Basófilos/metabolismo , Línea Celular , Humanos , Inmunoglobulina E/aislamiento & purificación , Inmunoglobulina E/metabolismo , Ratones , Unión Proteica , Receptores de IgE/metabolismoRESUMEN
Memory retrieval involves the reactivation of processes that were engaged at encoding. Using a Generalized Linear Model to test for effects of valence, our prior study suggests that memory for information previously encoded in a negative context reengages sensory processing regions at retrieval to a greater extent than positive. Here, we used partial least squares analyses of the same dataset to determine whether this valence-specific processing was one of the dominant patterns in the retrieval data. Trials previously paired with a face revealed a strong pattern of emotion that did not vary by valence, but for trials previously paired with a scene, an extensive network of regions was active during recollection of trials paired with negative content. These same regions were negatively correlated with recollection of trials paired with positive content. These results confirm that, despite no emotional content present during the time of retrieval, strong patterns of emotional study context are present in the data. Moreover, at least for trials paired with scenes at encoding, valence-specific networks are linked to episodic memory recollection, providing further support for recapitulation of sensory processing during recollection of negative emotional information.
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Encéfalo/fisiología , Emociones/fisiología , Memoria/fisiología , Vías Nerviosas/fisiología , Percepción Visual/fisiología , Adulto , Encéfalo/diagnóstico por imagen , Mapeo Encefálico , Femenino , Humanos , Procesamiento de Imagen Asistido por Computador , Imagen por Resonancia Magnética , Masculino , Vías Nerviosas/diagnóstico por imagen , Oxígeno/sangre , Estimulación Luminosa , Adulto JovenRESUMEN
Recapitulation involves the reactivation of cognitive and neural encoding processes at retrieval. In the current study, we investigated the effects of emotional valence on recapitulation processes. Participants encoded neutral words presented on a background face or scene that was negative, positive or neutral. During retrieval, studied and novel neutral words were presented alone (i.e., without the scene or face) and participants were asked to make a remember, know or new judgment. Both the encoding and retrieval tasks were completed in the fMRI scanner. Conjunction analyses were used to reveal the overlap between encoding and retrieval processing. These results revealed that, compared to positive or neutral contexts, words that were recollected and previously encoded in a negative context showed greater encoding-to-retrieval overlap, including in the ventral visual stream and amygdala. Interestingly, the visual stream recapitulation was not enhanced within regions that specifically process faces or scenes but rather extended broadly throughout visual cortices. These findings elucidate how memories for negative events can feel more vivid or detailed than positive or neutral memories.