Friends are a vital source of social relations throughout the lifespan and across developmental stages. Our knowledge of how friendships develop over time, especially from childhood through adulthood, is limited. Furthermore, it is now recognized that this specific type of relationship influences health across the life course in unique ways. Using…

Humans appear to intuitively grasp definitions foundational to formal geometry, like definitions that describe points as infinitely small and lines as infinitely long. Nevertheless, previous studies exploring human's intuitive natural geometry have consistently focused on geometric principles in planar Euclidean contexts and thus may not…

The study investigated age-related trends in moral identity goal characteristics, as proposed in previous research (Krettenauer, 2022a), by modifying the Self-Importance of Moral Identity Questionnaire (Aquino & Reed, 2002). Internally and externally motivated moral identity was assessed on varying levels of abstractness for promotion…

Gender and age are salient social categories from early in development. However, whether children's beliefs about gender and age intersect, such that gender stereotypes might be expressed differently when asked about children (compared to adults) has not been investigated. Here, in a preregistered study (N = 297), we examined if young children…

Existing research focused on social role destabilization (historical increases in role instability) and destandardization (historical increases in variability of role instability) has primarily focused on discrete social roles during discrete periods of development. Building on this work, we applied a macro approach to elucidate the extent to…

In pursuing goals, people seek favorable odds. We investigated whether young children use this fact to infer goals from people's actions across two experiments on Canadian 3- to 7-year-old children (N = 316; 167 girls, 149 boys). Participants' demographic information was not formally collected, but the region is predominantly middle-class and…

This study examined age-related patterns in exposure and affective reactivity to daily stressors across a 20-year time span among adults who were between 22 and 77 years old at their baseline interview. Longitudinal data from the National Study of Daily Experiences (NSDE) consisted of three bursts of eight consecutive nightly interviews of stress…

Adults have a vertical attention bias (VAB) that directs their focus toward object tops and scene bottoms. This is consistent with focusing attention on the informative aspects and affordances of the environment, and generally favoring a downward gaze. The smaller size of children, combined with their relatively limited interactions with objects…

This study investigated how adults over the lifespan flexibly adapt their use of prosocial speech acts when conveying bad news to communicative partners. Experiment 1a (N = 100 Scottish adults aged 18-72 years) assessed whether participants' use of prosocial speech acts varied according to audience design considerations (i.e., whether or not the…

Concurrent learning of adjacent and nonadjacent dependencies has been shown in adults only. This study extended this line of research by examining dependency-specific learning for both adjacent and nonadjacent dependencies concurrently in both adults and children. Seventy adults aged 18 to 64 (40 women, 30 men; Experiment 1) and 64 children aged…

We extend decades of research on infants' visual processing by examining their eye gaze during viewing of natural scenes. We examined the eye movements of a racially diverse group of 4- to 12-month-old infants (N = 54; 27 boys; 24 infants were White and not Hispanic, 30 infants were African American, Asian American, mixed race and/or Hispanic) as…

Little research has examined changes in personal identity over different periods of adult development. The aim of the present cross-sectional study was to target these changes through the characterization of the main dimensions in self-defining memories (SDMs; thematic content, specificity, integrative meaning, tension, contamination/redemption,…

Previous research shows that children evaluate the competence of others based on how effectively someone accomplished a goal, that is, based on the observed outcome of an action (e.g., number of attempts needed). Here, we investigate whether 5- to 10-year-old children and adults infer competence from how efficiently someone solves a task by…

Past research has demonstrated that both consequentialist motives (such as deterrence) and deontological motives (such as "just deserts") underlie children's and adults' punitive behavior. But what motives do we ascribe to others who pursue punishment? The present work explores this question by assessing which punitive motives children…

The current longitudinal study examined the predictive associations between the development of future perceptions in adolescence and depressive symptoms in adolescence and early and middle adulthood. Participants (N = 1,527; 48.3% female; broadly representative of Western Germany with respect to race/ethnicity and socioeconomic status) were…