This research will examine everyday conceptions of nostalgia. Nostalgia serves important psychological functions: it elevates positive affect, boosts self-regard, provides a sense of meaning, fosters self-continuity, and strengthens social connectedness. Yet in relevant studies participants are left to their own devices to conceptualise nostalgia. Also, disagreement exists on whether nostalgia's definitional weight should lie on "missing" aspects of the past or engaging in "sentimental thinking" about aspects of the past. Finally, the proposal findings will be generative, as they will enable investigators to experimentally induce and study nostalgia using an empirically-informed definition. An initial study will attempt to characterise which features or exemplars people perceive as more prototypical (ie central) versus less prototypical (ie peripheral) of nostalgia. This will be accomplished by using an established index of prototypicality, namely the frequency with which participants generate exemplars. The following wave of three studies will implement various techniques in an effort to discriminate in a valid way between central and peripheral nostalgia exemplar categories. Next, the research will seek to confirm in a further wave of three studies that these clusters are more versus less prototypical. These exemplar categories will be used as stimulus materials for the induction of nostalgia.

Study 1: Survey: Lay participants recruited from students, staff, and graduates of a British university and current students of a Midwestern US university listed features that described 'nostalgia.' Dataset: 1752 exemplars provided by 232 participants, coded into categories by 2 codersStudy 2: Survey: Lay participants rated how closely the 35 features from Study 1 related to nostalgia (higher rated features designated as central, lower rated features as peripheral). Dataset: 102 cases x 38 variablesStudy 3: College students and their parents recruited at university open days viewed stimuli on computer. Following a distractor task, participants were asked to (a) freely recall and (b) recognize from a list the stimuli they had seen. Dataset: 99 cases x 80 variablesStudy 4: Undergraduates viewed 140 words on computer screen and judged as quickly and accurately as possible whether each was a nostalgia feature (response and time in milliseconds recorded). Dataset: 53 cases x 429 variablesStudy 5: Undergraduates read vignettes in which a character's autobiographical event was described using central, peripheral, or no nostalgia features. Dataset: 252 cases (42 participants, 6 rows each) x 11 variablesStudy 6: Undergraduates brought to mind either a nostalgic or ordinary personal event and rated how well each of the nostalgia features described the event. Dataset: 56 cases x 47 variablesStudy 7: Students, community members, and members of an older adults volunteer database brought to mind a personal event that was either (a) nostalgic, (b) ordinary, (c) defined by central features, or (d) defined by peripheral features. They described the event and rated how well it fulfilled nostalgia functions (e.g., self-worth, self-continuity). Dataset: 193 cases x 51 variablesStudy 8: Students from 13 countries rated how closely the 35 features from Study 1 related to nostalgia. Dataset: 1267 cases x 62 variables