Perceived plausibility modulates hippocampal activity in episodic counterfactual thinking.

Episodic counterfactual thinking (ECT) consists of imagining alternative outcomes to past personal events. Previous research has shown that ECT shares common neural substrates with episodic future thinking (EFT): our ability to imagine possible future events. Both ECT and EFT have been shown to critically depend on the hippocampus, and past research has explored hippocampal engagement as a function of the perceived plausibility of an imagined future event. However, the extent to which the hippocampus is modulated by perceived plausibility during ECT is unknown. In this study, we combine two functional magnetic resonance imaging datasets to investigate whether perceived plausibility modulates hippocampal activity during ECT. Our results indicate that plausibility parametrically modulates hippocampal activity during ECT, and that such modulation is confined to the left anterior portion of the hippocampus. Moreover, our results indicate that this modulation is positive, such that increased activity in the left anterior hippocampus is associated with higher ratings of ECT plausibility. We suggest that neither effort nor difficulty alone can account for these results, and instead suggest possible alternatives to explain the role of the hippocampus during the construction of plausible and implausible ECT.

Not Every Thing Must Go.

In The Entangled Brain, Pessoa criticizes standard approaches in cognitive neuroscience in which the brain is seen as a functionally decomposable, modular system with causal operations built up hierarchically. Instead, he advocates for an emergentist perspective whereby dynamic brain networks are associated, not with traditional psychological categories, but with behavioral functions characterized in evolutionary terms. Here, we raise a number of concerns with such a radical approach. We ultimately believe that although much revision to cognitive neuroscience is welcome and needed, Pessoa's more radical proposals may be counterproductive.

Age differences in the functional architecture of the human brain.

The intrinsic functional organization of the brain changes into older adulthood. Age differences are observed at multiple spatial scales, from global reductions in modularity and segregation of distributed brain systems, to network-specific patterns of dedifferentiation. Whether dedifferentiation reflects an inevitable, global shift in brain function with age, circumscribed, experience-dependent changes, or both, is uncertain. We employed a multimethod strategy to interrogate dedifferentiation at multiple spatial scales. Multi-echo (ME) resting-state fMRI was collected in younger (n = 181) and older (n = 120) healthy adults. Cortical parcellation sensitive to individual variation was implemented for precision functional mapping of each participant while preserving group-level parcel and network labels. ME-fMRI processing and gradient mapping identified global and macroscale network differences. Multivariate functional connectivity methods tested for microscale, edge-level differences. Older adults had lower BOLD signal dimensionality, consistent with global network dedifferentiation. Gradients were largely age-invariant. Edge-level analyses revealed discrete, network-specific dedifferentiation patterns in older adults. Visual and somatosensory regions were more integrated within the functional connectome; default and frontoparietal control network regions showed greater connectivity; and the dorsal attention network was more integrated with heteromodal regions. These findings highlight the importance of multiscale, multimethod approaches to characterize the architecture of functional brain aging.

On the frequency and nature of the cues that elicit déjà vu and involuntary autobiographical memories.

Barzykowski and Moulin suggest that déjà vu and involuntary autobiographical memories recruit similar retrieval processes. Here, we invite the authors to clarify three issues: (1) What mechanism prevents déjà vu to happen more frequently? (2) What is the role of semantic cues in involuntary autobiographical retrieval? and (3) How déjà vu relates to non-believed memories?

Effects of mental simulation of future waterpipe tobacco smoking on attitudes, perceived harms and intended use among young adults.

The desire to engage in waterpipe tobacco smoking (WTS) may occur when smokers and nonsmokers conjure positive mental simulations of WTS. However, effects of these simulations on desire to smoke waterpipe tobacco and potential mediators are unexplored. This research addressed these effects among young adult waterpipe tobacco smokers and nonsmokers. Two online studies were conducted with adults ages 18-30. In Study 1, 200 smokers, 190 susceptible nonsmokers, and 182 nonsusceptible nonsmokers were randomized to mentally simulate or not WTS in the future. In Study 2, 234 smokers and 241 susceptible nonsmokers were randomized to four arms: no simulation or simulations that varied valence of experience (positive, negative or no valence provided). Main outcomes were immediate desire to smoke waterpipe tobacco, cognitive and affective attitudes, and perceived harms. In Study 1, mental simulations increased the desire to smoke waterpipe tobacco among smokers. In Study 2, asking participants to simulate WTS positively or with no valence instruction increased desire to smoke relative to negative valence instruction or no simulation. Negative simulations reduced perceived probability of smoking within a month compared to positive simulations. Effects on desire to engage in WTS were mediated by cognitive and affective attitudes among susceptible nonsmokers and by cognitive attitudes among smokers. These findings suggest that exploring when and how often mental simulations about WTS are evoked and their potency for promoting prevention and cessation of WTS merit further attention.

Rethinking the distinction between episodic and semantic memory: Insights from the past, present, and future.

On the 50th anniversary of Tulving's introduction of the celebrated distinction between episodic and semantic memory, it seems more than fitting to revisit his proposal in light of recent conceptual and methodological advances in the field. This Special Issue of Memory & Cognition brings together researchers doing cutting-edge work at the intersection between episodic and semantic memory to showcase studies directly probing this psychological distinction, as well as articles that seek to provide conceptual and theoretical accounts to understand their interaction. The 14 articles presented here highlight the need to critically examine the way in which we conceptualize not only the relationship between episodic and semantic memory, but also the interplay between declarative and non-declarative memory, and the myriad implications of such conceptual changes. In many ways, we suggest this Special Issue might serve as a call to action for our field, inspiring future work to challenge pre-existing conceptions and stimulate new directions in this fast-moving field.

Effects of category learning strategies on recognition memory.

Extant research has shown that previously acquired categorical knowledge affects recognition memory, and that differences in category learning strategies impact classification accuracy. However, it is unknown whether different learning strategies also have downstream effects on subsequent recognition memory. The present study investigates the effect of two unidimensional rule-based category learning strategies - learning (a) with or without explicit instruction, and (b) with or without supervision - on subsequent recognition memory. Our findings suggest that acquiring categorical knowledge increased both hits (Experiments 1 and 2) and false-alarms (Experiment 1) for category-congruent items regardless of the particular strategy employed in initially learning these categories. There were, however, small processing speed advantages during recognition memory for both explicit instruction and supervised practice relative to neither (Experiment 2). We discuss these findings in the context of how prior knowledge influences recognition memory, and in relation to similar findings showing schematic effects on episodic memory.

The moderating effects of nostalgia on mood and optimism during the COVID-19 pandemic.

The initial waves of the coronavirus pandemic amplified feelings of depression, psychological fatigue and pessimism for the future. Past research suggests that nostalgia helps to repair negative moods by boosting current and future-oriented positive affect, thereby strengthening psychological resilience. Accordingly, the present study investigated whether nostalgia moderated the relationship between pandemic experience and individual differences in mood and optimism. Across two studies we assessed psychosocial self-report data from a total of 293 online participants (22-72 years old; mean age 38; 109 females, 184 males) during the first two waves of the pandemic. Participants completed comprehensive questionnaires that probed state and trait characteristics related to mood and memory, such as the Profile of Mood States, Nostalgia Inventory and State Optimism Measure. Our findings indicate that during the initial wave of coronavirus cases, higher levels of nostalgia buffered against deteriorating mood states associated with concern over the pandemic. Nostalgia also boosted optimism for participants experiencing negative mood, and optimism predicted subjective mood improvement one week later. This shielding effect of nostalgia on optimism was replicated during the second wave of coronavirus cases. The present findings support the role of nostalgia in promoting emotional homeostasis and resilience during periods of psychological distress.

Differential contribution of anterior and posterior midline regions during mental simulation of counterfactual and perspective shifts in autobiographical memories.

Retrieving autobiographical memories induces a natural tendency to mentally simulate alternate versions of past events, either by reconstructing the perceptual details of the originally experienced perspective or the conceptual information of what actually occurred. Here we examined whether the episodic system recruited during imaginative experiences functionally dissociates depending on the nature of this reconstruction. Using fMRI, we evaluated differential patterns of neural activity and hippocampal connectivity when twenty-nine participants naturally recalled past negative events, shifted visual perspective, or imagined better or worse outcomes than what actually occurred. We found that counterfactual thoughts were distinguished by neural recruitment in dorsomedial prefrontal cortex, whereas shifts in visual perspective were uniquely supported by the precuneus. Additionally, connectivity with the anterior hippocampus changed depending upon the mental simulation that was performed - with enhanced hippocampal connectivity with medial prefrontal cortex for counterfactual simulations and precuneus for shifted visual perspectives. Together, our findings provide a novel assessment of differences between these common methods of mental simulation and a more detailed account for the neural network underlying episodic retrieval and reconstruction.

The phenomenology of remembering our moral transgressions.

People tend to believe that they truly are morally good, and yet they commit moral transgressions with surprising frequency in their everyday lives. To explain this phenomenon, some theorists have suggested that people remember their moral transgressions with fewer details, lower vivacity, and less clarity, relative to their morally good deeds and other kinds of past events. These phenomenological differences are thought to help alleviate psychological discomfort and to help people maintain a morally good self-concept. Given these motivations to alleviate discomfort and to maintain a morally good self-concept, we might expect our more egregious moral transgressions, relative to our more minor transgressions, to be remembered less frequently, with fewer details, with lower vivacity, and with a reduced sense of reliving. More severe moral transgressions might also be less central to constructions of personal identity. In contrast to these expectations, our results suggest that participants' more severe moral transgressions are actually remembered more frequently, more vividly, and with more detail. More severe moral transgressions also tend to be more central to personal identity. We discuss the implications of these results for the motivation to maintain a morally good self-concept and for the functions of autobiographical memory.

The centrality of remembered moral and immoral actions in constructing personal identity.

There is a widespread belief that morally good traits and qualities are particularly central to psychological constructions of personal identity. People have a strong tendency to believe that they truly are morally good. We suggest that autobiographical memories of past events involving moral actions may inform how we come to believe that we are morally good. In two studies, we investigated the role of remembered past events involving moral and immoral actions in constructing perceived personal identity. For morally right actions only, we found that remembered actions judged to be more morally right relative to less morally right were more central to personal identity (Study 1). We then found that remembered morally right actions were more central to personal identity than remembered morally wrong actions (Study 2). We discuss these findings in relation to recent research on morality and personal identity.

Phenomenology of counterfactual thinking is dampened in anxious individuals.

Counterfactual thinking (CFT), or simulating alternative versions of occurred events, is a common psychological strategy people use to process events in their lives. However, CFT is also a core component of ruminative thinking that contributes to psychopathology. Though prior studies have tried to distinguish adaptive from maladaptive CFT, our study provides a novel demonstration that identifies phenomenological differences across CFT in participants with varying levels of trait anxiety. Participants (N = 96) identified negative, regretful memories from the past 5 years and created a better counterfactual alternative (upward CFT), a worse counterfactual alternative (downward CFT), or simply recalled each memory. Participants with high levels of trait anxiety used more negative language when describing their mental simulations, reported lower ratings of composition during upward CFT, and reported more difficulty in imagining the emotion they would have felt had negative events turned out to be better. Additionally, participants with high anxiety thought that upward CFT was less likely to occur relative to individuals with low anxiety. These results help to clarify how mental simulations of aversive life events are altered in anxiety and serve as a stepping stone to future research uncovering the mechanisms of ruminative thought patterns.

Remembering moral and immoral actions in constructing the self.

Having positive moral traits is central to one's sense of self, and people generally are motivated to maintain a positive view of the self in the present. But it remains unclear how people foster a positive, morally good view of the self in the present. We suggest that recollecting and reflecting on moral and immoral actions from the personal past jointly help to construct a morally good view of the current self in complementary ways. More specifically, across four studies we investigated the extent to which people believe they have changed over time after recollecting their own moral or immoral behaviors from the personal past. Our results indicate that recollecting past immoral actions is associated with stronger impressions of dissimilarity and change in the sense of self over time than recollecting past moral actions. These effects held for diverse domains of morality (i.e., honesty/dishonesty, helping/harming, fairness/unfairness, and loyalty/disloyalty), and they remained even after accounting for objective, calendar time. Further supporting a motivational explanation, these effects held when people recollected their own past actions but not when they recollected the actions of other people.

How thinking about what could have been affects how we feel about what was.

Episodic counterfactual thoughts (CFT) and autobiographical memories (AM) involve the reactivation and recombination of episodic memory components into mental simulations. Upon reactivation, memories become labile and prone to modification. Thus, reactivating AM in the context of mentally generating CFT may provide an opportunity for editing processes to modify the content of the original memory. To examine this idea, this paper reports the results of two studies that investigated the effect of reactivating negative and positive AM in the context of either imagining a better (i.e. upward CFT) or a worse (i.e. downward CFT) alternative to an experienced event, as opposed to attentively retrieving the memory without mental modification (i.e. remembering) or no reactivation. Our results suggest that attentive remembering was the best strategy to both reduce the negative affect associated with negative AM, and to prevent the decay of positive affect associated with positive AM. In addition, reactivating positive, but not negative, AM with or without CFT modification reduces the perceived arousal of the original memory over time. Finally, reactivating negative AM in a downward CFT or an attentive remembering condition increases the perceived detail of the original memory over time.

Two challenges for a dual system approach to temporal cognition.

Hoerl & McCormack (H&M) propose a two-system account of temporal cognition. We suggest that, following other classic proposals where cognitive systems are putatively independent, H&M's two-system hypothesis should, at a minimum, involve (1) a difference in the nature of the representations upon which each system operates, and (2) a difference in the computations they carry out. In this comment we offer two challenges aimed at showing that H&M's proposal does not meet the minimal requirements (1) and (2).

What if? Neural activity underlying semantic and episodic counterfactual thinking.

Counterfactual thinking (CFT) is the process of mentally simulating alternative versions of known facts. In the past decade, cognitive neuroscientists have begun to uncover the neural underpinnings of CFT, particularly episodic CFT (eCFT), which activates regions in the default network (DN) also activated by episodic memory (eM) recall. However, the engagement of DN regions is different for distinct kinds of eCFT. More plausible counterfactuals and counterfactuals about oneself show stronger activity in DN regions compared to implausible and other- or object-focused counterfactuals. The current study sought to identify a source for this difference in DN activity. Specifically, self-focused counterfactuals may also be more plausible, suggesting that DN core regions are sensitive to the plausibility of a simulation. On the other hand, plausible and self-focused counterfactuals may involve more episodic information than implausible and other-focused counterfactuals, which would imply DN sensitivity to episodic information. In the current study, we compared episodic and semantic counterfactuals generated to be plausible or implausible against episodic and semantic memory reactivation using fMRI. Taking multivariate and univariate approaches, we found that the DN is engaged more during episodic simulations, including eM and all eCFT, than during semantic simulations. Semantic simulations engaged more inferior temporal and lateral occipital regions. The only region that showed strong plausibility effects was the hippocampus, which was significantly engaged for implausible CFT but not for plausible CFT, suggestive of binding more disparate information. Consequences of these findings for the cognitive neuroscience of mental simulation are discussed.

No evidence for unethical amnesia for imagined actions: A failed replication and extension.

In a recent study, Kouchaki and Gino (2016) suggest that memory for unethical actions is impaired, regardless of whether such actions are real or imagined. However, as we argue in the current study, their claim that people develop "unethical amnesia" confuses two distinct and dissociable memory deficits: one affecting the phenomenology of remembering and another affecting memory accuracy. To further investigate whether unethical amnesia affects memory accuracy, we conducted three studies exploring unethical amnesia for imagined ethical violations. The first study (N = 228) attempts to directly replicate the only study from Kouchaki and Gino (2016) that includes a measure of memory accuracy. The second study (N = 232) attempts again to replicate these accuracy effects from Kouchaki and Gino (2016), while including several additional variables meant to potentially help in finding the effect. The third study (N = 228) is an attempted conceptual replication using the same paradigm as Kouchaki and Gino (2016), but with a new vignette describing a different moral violation. We did not find an unethical amnesia effect involving memory accuracy in any of our three studies. These results cast doubt upon the claim that memory accuracy is impaired for imagined unethical actions. Suggestions for further ways to study memory for moral and immoral actions are discussed.

Why episodic memory may not be for communication.

Three serious challenges to Mahr & Csibra's (M&C's) proposal are presented. First, we argue that the epistemic attitude that they claim is unique to remembering also applies to some forms of imaginative simulations that aren't memories. Second, we argue that their account cannot accommodate critical neuropsychological evidence. Finally, we argue that their proposal looks unconvincing when compared to more parsimonious evolutionary accounts.

Exploring the experience of episodic past, future, and counterfactual thinking in younger and older adults: A study of a Colombian sample.

Although extant evidence suggests that many neural and cognitive mechanisms underlying episodic past, future, and counterfactual thinking overlap, recent results have uncovered differences among these three processes. However, the extent to which there may be age-related differences in the phenomenological characteristics associated with episodic past, future and counterfactual thinking remains unclear. This study used adapted versions of the Memory Characteristics Questionnaire and the Autobiographical Interview in younger and older adults to investigate the subjective experience of episodic past, future and counterfactual thinking. The results suggest that, across all conditions, younger adults generated more internal details than older adults. However, older adults generated more external details for episodic future and counterfactual thinking than younger adults. Additionally, younger and older adults generated more internal details, and gave higher sensory and contextual ratings, for memories rather than future and counterfactual thoughts. Methodological and theoretical consequences for extant theories of mental simulation are discussed.

Emotional intensity in episodic autobiographical memory and counterfactual thinking.

Episodic counterfactual thoughts-imagined alternative ways in which personal past events might have occurred-are frequently accompanied by intense emotions. Here, participants recollected positive and negative autobiographical memories and then generated better and worse episodic counterfactual events from those memories. Our results suggest that the projected emotional intensity during the simulated remembered/imagined event is significantly higher than but typically positively related to the emotional intensity while remembering/imagining the event. Furthermore, repeatedly simulating counterfactual events heightened the emotional intensity felt while simulating the counterfactual event. Finally, for both the emotional intensity accompanying the experience of remembering/imagining and the projected emotional intensity during the simulated remembered/imagined event, the emotional intensity of negative memories was greater than the emotional intensity of upward counterfactuals generated from them but lower than the emotional intensity of downward counterfactuals generated from them. These findings are discussed in relation to clinical work and functional theories of counterfactual thinking.