Self-Continuity.

Self-continuity is the subjective sense of connection between one's past and present selves (past-present self-continuity), between one's present and future selves (present-future self-continuity), or among one's past, present, and future selves (global self-continuity). We consider the motivational character of the three forms of self-continuity, their regulatory properties, and the internal or external factors that consolidate them. We also review their consequences for attitudes and judgments or decisions, motivation, intentions and behavior, and psychological and physical health. We further detail the psychological and behavioral benefits of self-discontinuity (i.e., a sense of disconnect among temporal selves). We next turn to the brain regions that are activated synchronously with self-continuity. We consider developmental perspectives on self-continuity, discuss collective self-continuity (along with its consequences and regulatory properties), and elaborate on cultural differences in self-continuity. This inaugural Annual Reviews chapter demonstrates the breadth, excitement, and sense of synergy among self-continuity researchers and points to promising research directions.

Dispositional forgiveness buffers paranoia following interpersonal transgression.

OBJECTIVE: To test a novel proposition that dispositional forgiveness has the unrecognized benefit of buffering feelings of paranoia following negative interpersonal experiences and interpersonal transgressions. METHODS: In Study 1 (N = 128), we used an experimental paradigm, the Prisoner's Dilemma Game (PDG), to test the premise that an interpersonal transgression increases state paranoia. Study 2 (N = 180) used a longitudinal design to test the central proposition that dispositional forgiveness buffers state paranoia following naturally occurring difficult (vs pleasant) interpersonal events. Study 3 (N = 102) used a novel experimental paradigm to determine the causal effect of manipulating forgiveness on paranoia. RESULTS: In Study 1, interpersonal transgressions in the PDG increased paranoia. In Study 2, paranoia was higher following difficult (rather than pleasant) events, and higher levels of dispositional forgiveness moderated the negative effect of difficult events on paranoia. In Study 3, there was a causal effect of forgiveness on (reduced) paranoia. CONCLUSIONS: This is the first evidence that (1) interpersonal transgressions increase paranoia, (2) high dispositional forgiveness moderates the deleterious effect of interpersonal transgression on paranoia, and (3) dispositional forgiveness is causally related to less paranoia.

Distress prospectively predicts higher nostalgia, and nostalgia prospectively predicts lower distress.

OBJECTIVE: We were concerned with the relation between distress and nostalgia. At the state level, extensive research has established that momentary nostalgia is evoked by (experimentally manipulated) distress. However, at the trait level, the directionality of this relation is unclear. We conducted a longitudinal study to clarify the directional relation between these two constructs. METHOD: We surveyed first-year university students (N = 3167) twice across six months. We assessed nostalgia, psychological distress (depression), and physical distress (somatization) at both timepoints. We also assessed Big Five personality at the first timepoint. RESULTS: Initial distress prospectively predicted increased nostalgia, and initial nostalgia prospectively predicted reduced distress, six months later and independently of the Big Five. CONCLUSIONS: Habitual nostalgia follows rather than precedes naturalistically occurring distress and serves to relieve it.

Food-evoked nostalgia.

In three studies, we examined food as an elicitor of nostalgia. Study 1 participants visualised eating either a nostalgic or regularly consumed food. Study 2 participants visualised consuming 12 foods. Study 3 participants consumed 12 flavour samples. Following their food experiences, all participants responded to questions regarding the profile of food-evoked nostalgia (i.e. autobiographical relevance, arousal, familiarity, positive and negative emotions) and several psychological functions (i.e. positive affect, self-esteem, social connectedness, meaning in life). Study 2 and 3 participants also reported their state nostalgia. Results revealed that food is a powerful elicitor of nostalgia. Food-evoked nostalgia has a similar contextual profile to previously examined elicitors, but is a predominantly positive emotional experience. Food-evoked nostalgia served multiple psychological functions and predicted greater state nostalgia.

Nostalgia enhances route learning in a virtual environment.

Salient landmarks enhance route learning. We hypothesised that semantically salient nostalgic landmarks would improve route learning compared to non-nostalgic landmarks. In two experiments, participants learned a route through a computer-generated maze using directional arrows and wall-mounted pictures. On the test trial, the arrows were removed, and participants completed the maze using only the pictures. In the nostalgia condition, pictures were of popular music artists and TV characters from 5 to 10 years ago. In the control condition, they were recent pictures of these same artists and characters. In Experiment 1, in the test trial, participants in the nostalgia condition completed the maze faster than controls. Experiment 2 conceptually replicated these findings and extended them by exploring boundary conditions. Participants had to learn two mazes sequentially. In Maze 1, we placed nostalgic/control landmarks only at non-decision points (whereas we placed them at decision points in Experiment 1). In Maze 2, we placed nostalgic/control landmarks at decision points during acquisition but removed them in the test trial (whereas they were present in the test trial in Experiment 1). In both mazes, participants in the nostalgia (compared to control) condition completed the test trial faster.

Induction of spatial anxiety in a virtual navigation environment.

Spatial anxiety (i.e., feelings of apprehension and fear about navigating everyday environments) can adversely impact people's ability to reach desired locations and explore unfamiliar places. Prior research has either assessed spatial anxiety as an individual-difference variable or measured it as an outcome, but there are currently no experimental inductions to investigate its causal effects. To address this lacuna, we developed a novel protocol for inducing spatial anxiety within a virtual environment. Participants first learnt a route using directional arrows. Next, we removed the directional arrows and randomly assigned participants to navigate either the same route (n = 22; control condition) or a variation of this route in which we surreptitiously introduced unfamiliar paths and landmarks (n = 22; spatial-anxiety condition). The manipulation successfully induced transient (i.e., state-level) spatial anxiety and task stress but did not significantly reduce task enjoyment. Our findings lay the foundation for an experimental paradigm that will facilitate future work on the causal effects of spatial anxiety in navigational contexts. The experimental task is freely available via the Open Science Framework ( https://osf.io/uq4v7/ ).

The Development and Validation of the Threat of Dementia Scale.

Dementia represents a substantial threat to the self. However, to date, there is no reliable way to measure how threatened people feel by dementia. This article reports on two online studies. In Study 1, 248 participants rated statements about dementia according to their threat to well-being. In Study 2, 99 participants (all students at the University of the West of England) completed the emerging scale (the Threat of Dementia Scale or ToDS). We validated this by examining its associations with conceptually related measures, including the revised Fraboni Scale of Ageism and the Fear of Alzheimer's Disease Scale. Study 1 yielded 13 statements that were highly intercorrelated and comprised a single factor. In Study 2, the ToDS demonstrated good construct validity and acceptable test-retest reliability. Higher levels of distancing predicted lower scores on the ToDS. The ToDS is a reliable and valid instrument that is the first statistically validated method of examining the extent to which dementia threatens well-being.

The Content of Nostalgic Memories Among People Living with Dementia.

Although dementia may affect the reliability of autobiographical memories, the psychological properties of nostalgic memories may be preserved. We compared the content of nostalgic (n = 36) and ordinary (n = 31) narratives of 67 participants living with dementia. Narratives were rated according to their self-oriented, social, and existential properties, as well as their affective content. Social properties and affective content were assessed using a linguistic word count procedure. Compared to the ordinary narratives described in the control condition, nostalgic narratives described a typical events, expressed more positive affect, and had more expressions of self-esteem and self-continuity. They were also rated higher on companionship, connectedness and the closeness of relationships, and reflected life as being meaningful. Despite their cognitive impairment, people living with dementia experience nostalgia in similar ways to cognitively healthy adults, with their nostalgic narratives containing self-oriented, social, and existential properties.

Nostalgia, reflection, brooding: Psychological benefits and autobiographical memory functions.

We sought to clarify the psychological profile of experimentally induced nostalgia, compared to two other modes of thinking about one's past-reflection and brooding-also experimentally induced. We tested both British and Chinese participants. Our main hypothesis was that nostalgia's profile is more positive in terms of six psychological benefits and seven autobiographical memory functions. The results were consistent with the hypothesis. In regard to psychological benefits, nostalgia (vs. reflection and brooding) increased positive affect, self-esteem, self-continuity, social connectedness, and meaning in life. Furthermore, nostalgia increased optimism relative to brooding (but not reflection). In regard to autobiographical memory functions, nostalgia (vs. reflection and brooding) led to higher boredom reduction, conversation, intimacy maintenance, and death preparation, as well as lower bitterness revival. Nostalgia also elevated teach/inform relative to brooding (but not reflection). The findings were similar for British and Chinese participants.

Nostalgia strengthens global self-continuity through holistic thinking.

Nostalgia, a sentimental longing for one's meaningful past, promotes global self-continuity (GSC), a sense of connection among one's past, present, and future selves. We identified a cognitive mechanism for this effect: holistic thinking, and in particular interactional causality (presupposing multiple causes that interact to influence an object's behaviour). In three studies, using measurement-of-mediation and experimental-causal-chain designs, nostalgia was related to, and caused, higher GSC through interactional causality. In cross-sectional Study 1, trait nostalgia was associated with GSC via interactional causality. In Study 2, induced nostalgia led to higher interactional causality and ensuing GSC. In Study 3, manipulated interactional causal thinking increased GSC.

Mental transportation mediates nostalgia's psychological benefits.

Nostalgizing confers social, existential, and self-oriented psychological benefits or functions. But how does the experience of nostalgia conduce to these functions? We propose that it does so, in part, through mental transportation, which involves mentally leaving one's current space and transporting oneself into a past event. We addressed the role of mental transportation in one daily diary study and two experiments (N = 514). By assessing daily experiences of nostalgia in Study 1, we found that, on days in which participants felt more nostalgic, they were more likely to experience mental transportation. Following a narrative induction of nostalgia, we assessed mental transportation (Studies 2 and 3) and the three putative nostalgia functions: social, existential, self-oriented (Study 3). Nostalgic (vs. control) participants reported greater mental transportation (Studies 2 and 3), which in turn was associated with stronger functions (Study 3). The findings portray mental transportation as a key mechanism underlying the psychological benefits of nostalgia.

The past as a resource for the bereaved: nostalgia predicts declines in distress.

Nostalgia, a sentimental longing for one's past, can serve as a resource for individuals coping with discomforting experiences. The experience of bereavement poses psychological and physical risks. In a longitudinal study, we examined whether dispositional nostalgia predicted reductions in distress associated with the death of a loved one. Undergraduate students (N = 133) provided information regarding their loss (time elapsed since loss, expectedness) and levels of initial grief, nostalgia, and distress (hyperarousal, intrusion, avoidance) at three time points over a one-month period (Times 2 and 3 occurred one week and one month after the initial session, respectively). Individuals experiencing higher nostalgia reported a decrease in intrusive thoughts across time, whereas those experiencing lower nostalgia reported no change in intrusive thoughts across time. Hyperarousal (physical symptoms, negative feelings) decreased across time among individuals with higher initial grief who experienced greater nostalgia, but increased across time among those with higher initial grief who experienced lesser nostalgia. No changes occurred in avoidance. Nostalgia can palliate bereavement.

Nostalgia proneness and empathy: Generality, underlying mechanism, and implications for prosocial behavior.

OBJECTIVE: Nostalgia is a sentimental longing for one's past. We examined the hypotheses (rooted in attachment theory and research) that nostalgia prone individuals, by virtue of their greater attachment security, are more empathic and enact more prosocial behavior. METHOD: In five studies, testing 1,923 participants (Nrange  = 132-823, 52.42% women, Agerange  = 8-90 years), we measured nostalgia proneness and affective empathy. Additionally, we measured cognitive empathy in Study 3, attachment security in Studies 4-5, and prosocial behavior in Study 5. RESULTS: Nostalgia proneness was positively related to affective empathy among younger and older adults (Studies 1, 3-5) and among children (Study 2). This association was stronger for affective empathy than cognitive empathy (Study 3). Also, attachment security mediated the relation between nostalgia proneness and affective empathy (Studies 4-5). Finally, nostalgia prone individuals were more likely to engage in prosocial behavior, and this relation was serially mediated by attachment security and affective empathy (Study 5). CONCLUSION: The findings establish the empathic and prosocial character of nostalgia prone individuals, and clarify their personality profile.

Anticipated nostalgia: Looking forward to looking back.

Anticipated nostalgia is a new construct that has received limited empirical attention. It concerns the anticipation of having nostalgic feelings for one's present and future experiences. In three studies, we assessed its prevalence, content, emotional profile, and implications for self-regulation and psychological functioning. Study 1 revealed that anticipated nostalgia most typically concerns interpersonal relationships, and also concerns goals, plans, current life, and culture. Further, it is affectively laden with happiness, sadness, bittersweetness, and sociality. Studies 2 and 3 assessed the implications of anticipated nostalgia for self-regulation and psychological functioning. In both studies, positive evaluation of a personal experience was linked to stronger anticipated nostalgia, and anticipated nostalgia was linked to savouring of the experience. In Study 3, anticipated nostalgia measured prior to an important life transition predicted nostalgia a few months after the transition, and post-transition nostalgia predicted heightened self-esteem, social connectedness, and meaning in life.

Hungering for the past: Nostalgic food labels increase purchase intentions and actual consumption.

We proposed that nostalgic labels strengthen the appeal of food items when the items are intrinsically nostalgic (e.g., related to one's childhood). Nostalgic labels do so by fostering a sense of food comfort (i.e., safety and security) among potential consumers. Experiment 1, testing a Chinese sample, confirmed that nostalgic (vs. descriptive) labels strengthen purchase intentions of food items when such items are intrinsically nostalgic. Experiment 2 showed that nostalgic (vs. descriptive) food labels strengthen purchase intentions of intrinsically nostalgic items, and do so by virtue of their capacity to elevate food comfort. This experiment tested a U.S. sample, thus broadening the cross-cultural generalizability of the findings. Experiment 3, testing a Chinese sample, replicated the Experiment 2 findings using nostalgic versus descriptive labels of a food item, and ruled out the influence of an alternative mediator, perceived food healthiness. Finally, Experiment 4, testing also a Chinese sample, revealed that restaurant dishes are more likely to be consumed when advertised with a nostalgic (than descriptive) label. The current work makes theoretical contributions to literature on food consumption and emotions, and has practical implications for harnessing nostalgia for dietary purposes.

A prologue to nostalgia: savouring creates nostalgic memories that foster optimism.

How are nostalgic memories created? We considered savouring as one process involved in the genesis of nostalgia. Whereas nostalgia refers to an emotional reflection upon past experiences, savouring is a process in which individuals deeply attend to and consciously capture a present experience for subsequent reflection. Thus, having savoured an experience may increase the likelihood that it will later be reflected upon nostalgically. Additionally, to examine how cognitive and emotional processes are linked across time, we tested whether nostalgia for a previously savoured experience predicts optimism for the future. Retrospective reports of having savoured a positive event were associated with greater nostalgia for the event (Study 1). Retrospective reports of savouring a time period (college) were associated with greater nostalgia for that time period when participants were in a setting (alumni reunion event) that prompted thoughts of the time period (Study 2). Savouring an experience predicted nostalgia for the experience 4-9 months later (Study 3). Additionally, nostalgia was associated with greater optimism (Studies 2-3). Thus, savouring provides a foundation for nostalgic memories and an ensuing optimism.

Coping with noise in social dilemmas: Group representatives fare worse than individuals because they lack trust in others' benign intentions.

Research on interindividual-intergroup discontinuity has illuminated distinct patterns of cognition, motivation, and behavior in interindividual versus intergroup contexts. However, it has examined these processes in laboratory environments with perfect transparency, whereas real-life interactions are often characterized by noise (i.e., misperceptions and unintended errors). This research compared interindividual and intergroup interactions in the presence or absence of noise. In a laboratory experiment, participants played 35 rounds of a dyadic give-some dilemma, in which they acted as individuals or group representatives. Noise was manipulated, such that players' intentions either were perfectly translated into behavior or could deviate from their intentions in certain rounds (resulting in less cooperative behavior). Noise was more detrimental to cooperation in intergroup contexts than in interindividual contexts, because (a) participants who formed benign impressions of the other player coped better with noise, and (b) participants were less likely to form such benign impressions in intergroup than interindividual interactions.

Selective forgetting of self-threatening statements: Mnemic neglect for dementia information in people with mild dementia.

OBJECTIVE: We tested whether people with dementia manifest selective forgetting for self-threatening information, the mnemic neglect effect (MNE). This selective forgetting is observed among healthy adults in the recall, but not the recognition, of self-threatening feedback. METHODS: Sixty-four statements about dementia were rated for their level of negativity by 280 staff and students at University of the West of England. The 12 statements rated as most negative and the 12 statements rated as least negative were then read to 62 people with dementia. Participants were randomized to 1 of 2 conditions with the statements referring either to self or to another person. High-negativity and self-referent statements had strong threat potential. Participants recalled the statements and then completed a recognition task, which consisted of the 24 previously read statements and 24 new statements. RESULTS: Participants manifested the MNE: They recalled fewer high-negativity (compared with low-negativity) statements, but only when these referred to the self rather than another person. This pattern occurred independently of levels of depression or anxiety. Participants also made more self-protective intrusion errors when the statements referred to the self than another person. Participants did not differ in their recognition of statements. CONCLUSION: The MNE occurs among people with dementia. The selective forgetting of highly negative, self-referent statements serves to protect the self against the threat that dementia represents. Given the similarities between the MNE and the clinical phenomenon of repression, the findings may mark psychological processes that are implicated in the acceptance (or lack thereof) of a dementia diagnosis.

Autobiographical memory functions of nostalgia in comparison to rumination and counterfactual thinking: similarity and uniqueness.

We compared and contrasted nostalgia with rumination and counterfactual thinking in terms of their autobiographical memory functions. Specifically, we assessed individual differences in nostalgia, rumination, and counterfactual thinking, which we then linked to self-reported functions or uses of autobiographical memory (Self-Regard, Boredom Reduction, Death Preparation, Intimacy Maintenance, Conversation, Teach/Inform, and Bitterness Revival). We tested which memory functions are shared and which are uniquely linked to nostalgia. The commonality among nostalgia, rumination, and counterfactual thinking resides in their shared positive associations with all memory functions: individuals who evinced a stronger propensity towards past-oriented thought (as manifested in nostalgia, rumination, and counterfactual thinking) reported greater overall recruitment of memories in the service of present functioning. The uniqueness of nostalgia resides in its comparatively strong positive associations with Intimacy Maintenance, Teach/Inform, and Self-Regard and weak association with Bitterness Revival. In all, nostalgia possesses a more positive functional signature than do rumination and counterfactual thinking.

Sociality and intergenerational transfer of older adults' nostalgia.

Interest in nostalgia has blossomed, yet its nature in older adulthood and potential for intergenerational transfer to younger adults has remained neglected. In Experiment 1, we focused on the content of older adults' nostalgic (vs. ordinary) recollections and asked whether older adults' nostalgia could be transferred to younger adults. We showed that nostalgia expressed in older adults' narratives was positively associated with nostalgia reported by young-adult readers. In Experiment 2, undergraduates read a nostalgic or ordinary narrative written by an older adult. Then they rated their own nostalgia as well as their perceived social connectedness, self-continuity, and meaning in life. Exposure to older adults' nostalgic (vs. ordinary) narratives promoted concurrent nostalgia among young adults, along with associated psychological benefits (social connectedness, self-continuity, meaning). The findings illustrate the potential for intergenerational transfer of nostalgia through written narratives, and attest to the universality of nostalgic themes across younger and older adults.