Common marmosets (<Emphasis Type="Italic">Callithrix jacchus</Emphasis>) do not utilize social information in three simultaneous social foraging tasks

Social foraging is suggested to increase foraging efficiency, as individuals might benefit from public information acquired by monitoring the foraging activities of other group members. We conducted a series experiments with captive common marmosets (Callithrix jacchus) to investigate to what extent marmosets utilize social information about food location when foraging simultaneously with conspecifics. Subjects were confronted with dominant and subordinate demonstrators in three experiments which differed in the amount of information about food location available to the demonstrators. In all three experiments, the focal subjects’ performance in the social condition was not enhanced in comparison to a non-social control condition. Because we could rule out kleptoparasitism and aggressive displacements as explanations, we argue that the subjects’ tendency for scramble competition by avoiding others and dispersing over the foraging area seems to inhibit or mask the acquisition of social information about the location of rewarded patches.     

Native Amazonian children forego egalitarianism in merit‐based tasks when they learn to count

Cooperation often results in a final material resource that must be shared, but deciding how to distribute that resource is not straightforward. A distribution could count as fair if all members receive an equal reward (egalitarian distributions), or if each member's reward is proportional to their merit (merit‐based distributions). Here, we propose that the acquisition of numerical concepts influences how we reason about fairness. We explore this possibility in the Tsimane’, a farming‐foraging group who live in the Bolivian rainforest. The Tsimane’ learn to count in the same way children from industrialized countries do, but at a delayed and more variable timeline, allowing us to de‐confound number knowledge from age and years in school. We find that Tsimane’ children who can count produce merit‐based distributions, while children who cannot count produce both merit‐based and egalitarian distributions. Our findings establish that the ability to count – a non‐universal, language‐dependent, cultural invention – can influence social cognition.     

Do sheep (<Emphasis Type="Italic">Ovis aries</Emphasis>) categorize plant species according to botanical family?

The ability of grazing herbivores to assign food types to categories by relying on certain relevant criteria could considerably reduce cognitive demand and increase their foraging efficiency when selecting among many different plant items. Grasses and legumes differ functionally in vegetation communities as well as in nutritive value. We aimed to determine whether sheep can generalize an aversion they learnt for a grass or a legume species to another species of the same functional type and consequently whether botanical family is a potential level of categorization. Over four successive weeks, 12 lambs were conditioned against either a freshly cut grass (tall fescue—Festuca arundinacea, N = 6) or legume species (sainfoin—Onobrychis viciifolia, N = 6) using a negative post-ingestive stimulus (lithium chloride) on day 1. Preference of all lambs between another grass (cocksfoot—Dactylis glomerata) and another legume (alfalfa—Medicago sativa) was assessed on day 3 by measuring their relative consumptions. Preference for alfalfa progressively became lower for lambs that were conditioned against sainfoin than against tall fescue, indicating that lambs generalized the aversion between species along some perceptual gradient and classed the considered grasses and legumes in distinct categories. Beyond this original result, the question now is to identify which specific plant characteristics or functional traits the animals rely on in order to form categories.     

Lifespan differences in cortical dynamics of auditory perception

Using electroencephalographic recordings (EEG), we assessed differences in oscillatory cortical activity during auditory‐oddball performance between children aged 9–13 years, younger adults, and older adults. From childhood to old age, phase synchronization increased within and between electrodes, whereas whole power and evoked power decreased. We conclude that the cortical dynamics of perceptual processing undergo substantial reorganization from childhood to old age, and discuss possible reasons for the inverse relation between age trends in phase synchronization and power, such as lifespan differences in neural background activity, or a lifespan shift from rate coding in children to temporal coding in adults.     

Does spatial learning ability of common voles (<Emphasis Type="Italic">Microtus arvalis</Emphasis>) and bank voles (<Emphasis Type="Italic">Myodes glareolus</Emphasis>) constrain foraging efficiency?

Place learning abilities represent adaptations that contribute also to foraging efficiency under given spatio-temporal conditions. We investigated if this ability in turn constrains decision making in two sympatric vole species: while the herbivorous common vole (Microtus arvalis) feeds on spatio-temporally predictable food resources (e.g. roots, tubers and shoots of plant tubers), the omnivorous bank vole (Myodes glareolus) additionally subsists on temporally unpredictable food resources (e.g. insects and seeds). Here, we compare the spatial reference memory and working memory of the two species. In an automated operant home cage with eight water places, female voles either had to learn the fixed position of non-depletable places (reference memory task) or learn and avoid previously visited water places depleted in a single visit (win-shift task). In the reference memory task, Microtus females required significantly more choices to find all water places, initially performed slightly worse than Myodes females, and displayed slightly lower asymptotic performance. Both species were highly similar in new learning of the same task. In the more complex win-shift task, asymptotic performance was significantly lower in Microtus (72% correct) than in Myodes (79%). Our results suggest that both vole species resemble each other in their efficiency to exploit habitats with low spatio-temporal complexity but may differ in their efficiency at exploiting habitats with temporally changing spatial food distributions. The results imply that spatial ability adjusted to specific food distributions may impair flexible use of habitats that differ in their food distribution and therefore, decrease a species’ chances of survival in highly dynamic environments.     

Executive function on the Psychology Experiment Building Language tests

The measurement of executive function has a long history in clinical and experimental neuropsychology. The goal of the present report was to determine the profile of behavior across the lifespan on four computerized measures of executive function contained in the recently developed Psychology Experiment Building Language (PEBL) test battery and evaluate whether this pattern is comparable to data previously obtained with the non-PEBL versions of these tests. Participants (N = 1,223; ages, 5–89 years) completed the PEBL Trail Making Test (pTMT), the Wisconsin Card Sort Test (pWCST; Berg, Journal of General Psychology, 39, 15–22, 1948; Grant & Berg, Journal of Experimental Psychology, 38, 404–411, 1948), the Tower of London (pToL), or a time estimation task (Time-Wall). Age-related effects were found over all four tests, especially as age increased from young childhood through adulthood. For several tests and measures (including pToL and pTMT), age-related slowing was found as age increased in adulthood. Together, these findings indicate that the PEBL tests provide valid and versatile new research tools for measuring executive functions.     

Prospective memory across the lifespan: Investigating the contribution of retrospective and prospective processes

Prospective memory performance follows an inverted U-shaped function across the lifespan. Findings on the relative contribution of purely prospective memory and retrospective memory processes within prospective memory to this trajectory are scarce and inconclusive. We analyzed age-related differences in prospective memory performance across the lifespan in a cross-sectional design including six age groups (N = 99, 7–83 years) and investigated possible mechanisms by experimentally disentangling the relative contributions of retrospective memory and purely prospective memory processes. Results confirmed the inverted U-shaped function of prospective memory performance across the lifespan. A significant interaction between process type and age group was observed indicating differential relative contributions of retrospective memory and purely prospective memory processes on the development of prospective memory performance. Our results showed that mainly the pure prospective memory processes within prospective memory lead to lower prospective memory performance in young children and old adults. Moreover, the relative contributions of the retrospective memory and purely prospective memory processes are not uniform at both ends of the lifespan, i.e., in later adulthood the purely prospective memory processes seem to determine performance to an even greater extent than in childhood. Nevertheless, age effects were also observed in the retrospective component which thus contributed to the prospective memory performance differences between the age groups.     

Differences in the use of autobiographical memory across the adult lifespan

Current research distinguishes between self, directive and social function of autobiographical memories (AMs). To date, only few studies have investigated these functions across adulthood. The comparison of different age groups requires that the functions of AM are measured in the same way across groups (measurement invariance, MI). Additionally to the average use of AM, the factor variances and factor covariances among the three functions were examined across adulthood. In the present study, 1290 adults (aged between 17 and 93 years) completed the Thinking about Life Experiences Questionnaire (TALE), which measures the overall use of AMs for self, directive and social purposes. The sample was divided into five age groups and partial strong MI was established using multigroup confirmatory factor analysis. The results showed an increase in the factor associations as well as a decrease in the factor mean levels of all three functions across age groups. Both findings could be adequately described by linear functions of age. The factor variances were on most parts equal across age groups. These results strengthen the assumption that—from a lifespan developmental perspective—the use of AM may be aligned with relatively normative developmental tasks in a given society.     

Sex differences in facial emotion perception ability across the lifespan

Perception of emotion in the face is a key component of human social cognition and is considered vital for many domains of life; however, little is known about how this ability differs across the lifespan for men and women. We addressed this question with a large community sample (N?=?100,257) of persons ranging from younger than 15 to older than 60 years of age. Participants were viewers of the television show “Tout le Monde Joue”, and the task was presented on television, with participants responding via their mobile devices. Applying latent variable modeling, and establishing measurement invariance between males and females and across age, we found that, for both males and females, emotion perception abilities peak between the ages of 15 and 30, with poorer performance by younger adults and declining performance after the age of 30. In addition, we show a consistent advantage by females across the lifespan, which decreases in magnitude with increasing age. This large scale study with a wide range of people and testing environments suggests these effects are largely robust. Implications are discussed.     

A Big Five approach to self-regulation: personality traits and health trajectories in the Hawaii longitudinal study of personality and health

Self-regulatory processes influencing health outcomes may have their origins in childhood personality traits. The Big Five approach to personality was used here to investigate the associations between childhood traits, trait-related regulatory processes and changes in health across middle age. Participants (N = 1176) were members of the Hawaii longitudinal study of personality and health. Teacher assessments of the participants’ traits when they were in elementary school were related to trajectories of self-rated health measured on 6 occasions over 14 years in middle age. Five trajectories of self-rated health were identified by latent class growth analysis: Stable Excellent, Stable Very Good, Good, Decreasing and Poor. Childhood Conscientiousness was the only childhood trait to predict membership in the Decreasing class vs. the combined healthy classes (Stable Excellent, Stable Very Good and Good), even after controlling for adult Conscientiousness and the other adult Big Five traits. The Decreasing class had poorer objectively assessed clinical health measured on one occasion in middle age, was less well-educated, and had a history of more lifespan health-damaging behaviors compared to the combined healthy classes. These findings suggest that higher levels of childhood Conscientiousness (i.e. greater self-discipline and goal-directedness) may prevent subsequent health decline decades later through self-regulatory processes involving the acquisition of lifelong healthful behavior patterns and higher educational attainment.     

The Center for Lifespan Psychology at the Max Planck Institute for Human Development: Overview of conceptual agenda and illustration of research activities

Founded in 1981 by the late Paul B. Baltes, the Center for Lifespan Psychology at the Max Planck Institute for Human Development has helped to establish lifespan psychology as a distinct conceptual approach within developmental psychology. Recently, the Center has extended its research programme into developmental behavioural neuroscience. Here, we provide an overview of the Center's conceptual agenda, and present two of its seven research projects in greater detail. Work at the Center is guided by three propositions: (1) to study lifespan changes in behaviour as interactions among maturation, learning, and senescence; (2) to develop theories and methods that integrate empirical evidence across domains of functioning, timescales, as well as behavioural and neuronal levels of analysis; (3) to identify mechanisms of development by exploring age-graded differences in plasticity. The Intra-Person Dynamics Project studies the organization of cognitive abilities within individuals of different ages, and investigates lifespan age differences in the plasticity and components of episodic memory performance. The Sensorimotor–Cognitive Couplings Project examines lifespan differences in dynamic dependencies between sensorimotor and cognitive performance. Both projects combine behavioural assessments with methods from developmental neuroscience to delineate age-graded changes in brain–behaviour mappings. Current research in other projects includes: (1) behavioural development in very old age, as assessed in the Berlin Aging Study; (2) the interplay of motivation, affect, and cognition in developmental regulation; (3) behavioural and electrophysiological mechanisms of social interaction from infancy to adulthood; and (4) formal and statistical issues in structural equation modelling, with an emphasis on latent growth curve modelling. Graduate education and research at the Center profit greatly from cooperation with other institutions in Berlin and Potsdam as well as from national and international collaboration.     

Gratitude across the life span: Age differences and links to subjective well-being

Abstract

Gratitude has been described as an adaptive evolutionary mechanism that is relevant to healthy psychological and interpersonal outcomes. Questions remain as to whether the presence and benefits of gratitude are consistent from young adulthood to old age; prior research has yielded mixed evidence. We examined the magnitude and direction of age differences in gratitude in three samples (combined N = 31,206). We also examined whether gratitude was associated with greater/lesser well-being at different periods in the life course. We found that the experience of gratitude was greatest in older adults and least in middle aged and younger adults. Further, we found that the associations between gratitude and subjective well-being remained relatively constant across the lifespan. Findings are discussed from a developmental perspective.     

How Do Children Restrict Their Linguistic Generalizations? An (Un‐)Grammaticality Judgment Study

A paradox at the heart of language acquisition research is that, to achieve adult‐like competence, children must acquire the ability to generalize verbs into non‐attested structures, while avoiding utterances that are deemed ungrammatical by native speakers. For example, children must learn that, to denote the reversal of an action, un‐ can be added to many verbs, but not all (e.g., roll/unroll; close/*unclose). This study compared theoretical accounts of how this is done. Children aged 5–6 (N = 18), 9–10 (N = 18), and adults (N = 18) rated the acceptability of un‐ prefixed forms of 48 verbs (and, as a control, bare forms). Across verbs, a negative correlation was observed between the acceptability of ungrammatical un‐ prefixed forms (e.g., *unclose) and the frequency of (a) the bare form and (b) alternative forms (e.g., open), supporting the entrenchment and pre‐emption hypotheses, respectively. Independent ratings of the extent to which verbs instantiate the semantic properties characteristic of a hypothesized semantic cryptotype for un‐ prefixation were a significant positive predictor of acceptability, for all age groups. The relative importance of each factor differed for attested and unattested un‐ forms and also varied with age. The findings are interpreted in the context of a new hybrid account designed to incorporate the three factors of entrenchment, pre‐emption, and verb semantics.     

Spontaneous performance of wild baboons on three novel food-access puzzles

Although the technical problem-solving expertise of nonhuman primates has been investigated extensively in captivity, few species have been tested in their natural habitats. Here I examine the physical cognition of wild savanna baboons (Papio anubis), a species that occupies an omnivorous foraging niche in which a variety of embedded food items are extracted and processed. Baboons were tested on three puzzles, each involving high-quality food that required removal from a novel obstruction: (1) a string-pulling puzzle in which food was hung from tree branches, (2) a twig-dipping puzzle in which food was embedded in a vertical tube, and (3) a stick-pushing puzzle in which food was contained in a horizontal conduit. The baboons failed to solve the second and third puzzles even when tools had been appropriately positioned in advance. And although they solved the first puzzle, their actions (running while holding food that was still attached to the string), suggested they did not fully comprehend the string’s connective property. The baboons’ performance might reflect the time constraints of life in the wild, which relative to captivity may provide fewer opportunities for the development of understanding about the physical properties of objects and their potential uses as tools. Further experiments on the physical cognition of baboons and many other primate species in their natural habitats would help test this ontogenetic hypothesis. Such field experiments would be especially fruitful if they continued to target extractive foragers like baboons: these experiments could simultaneously provide a test of phylogenetic hypotheses that invoke extractive foraging as the key stimulus for brain expansion in savanna-dwelling hominids. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Personality assessment in the Great Apes: Comparing ecologically valid behavior measures, behavior ratings, and adjective ratings

Three methods of personality assessment (behavior measures, behavior ratings, adjective ratings) were compared in 20 zoo-housed Great Apes: bonobos (Pan paniscus), chimpanzees (Pan troglodytes verus), gorillas (Gorilla gorilla gorilla), and orangutans (Pongo pygmaeus abelii). To test a new bottom-up approach, the studied trait constructs were systematically generated from the species’ behavioral repertoires. The assessments were reliable, temporally stable, and showed substantial cross-method coherence. In most traits, behavior ratings mediated the relations between adjective ratings and behavior measures. Results suggest that high predictability of manifest behavior is best achieved by behavior ratings, not by adjectives. Empirical evidence for trait constructs beyond current personality models points to the necessity of broad and systematic approaches for valid inferences on a species’ personality structure.     

Facilitation by Variation: Right-to-Left Learning of English Yes/No Questions

This study advances the hypothesis that optional structural variation in language facilitates syntactic learning (facilitation‐by‐variation). Support for this is provided by a right‐to‐left‐elaboration acquisition model for English yes/no questions (YNQs). Previous studies have focused on the acquisition of ‘‘inverted’’ YNQs, a cornerstone of nativist theories of language development. Data from five American children (1;3 to 5;1) and their parents show that children hear a range of adult questions (Coming?You coming?Are you coming?), not all inverted. These variants are ordered from structurally least complex noncanonical forms to complex canonical inverted forms. I use state‐of‐the‐art econometric techniques to estimate breakpoints in YNQ time series and show that noncanonical questions emerge early in children’s speech and facilitate acquisition of canonical ones. This incremental structure‐building process relies on an adjunction strategy that augments noncanonical questions with initial auxiliaries and subjects. Development proceeds incrementally from right to left to derive auxiliary‐initial structures.     

A Closer Look at Life Goals Across Adulthood: Applying a Developmental Perspective to Content,Dynamics, and Outcomes of Goal Importance and Goal Attainability

It is well established that goals energize and direct behaviour across the lifespan. To better understand how goals are embedded in people's lives across adulthood, the present research examined life goals' content (health, personal growth, prosocial engagement, social relations, status, work), dynamics (interplay between goal importance and goal attainability), and outcomes (subjective well‐being) from a developmental perspective. We argue that people rate those goals as important and attainable that enable them to master developmental tasks, that they adapt their goals to personal capacities, and that goals predict subjective well‐being after 2 and 4 years. The sample included 973 individuals (18–92 years old, M = 43.00 years) of whom 637 participated 2 years later and 573 participated 4 years later. Goal importance and well‐being were assessed at all occasions and goal attainability at the first two occasions. Results indicated that age was negatively associated with importance and attainability of personal‐growth, status, and work goals but positively associated with importance and attainability of prosocial‐engagement goals. The association between goal importance and attainability was largely bidirectional over time; and goal attainability, rather than goal importance, was positively linked to later well‐being. Implications of these findings are discussed in light of adult lifespan development. © 2019 European Association of Personality Psychology     

Psychological contract breach and job attitudes: A meta-analysis of age as a moderator

The aim of this study was to examine the influence of age in the relation between psychological contract breach and the development of job attitudes. Based on affective events, social exchange, and lifespan theory, we hypothesized that (1) psychological contract breach would be related negatively to job attitudes, and (2) that age would moderate these relations. The hypotheses were tested by means of a meta-analysis of k = 60 studies, using Weighted Least Squares estimation. Our results supported both hypotheses for the outcomes trust and organizational commitment. However, for job satisfaction the moderating influence of age was in the unexpected direction. The relations between contract breach and trust and organizational commitment were indeed stronger for younger workers, whereas the relation between contract breach and job satisfaction was stronger for older workers. The implications are discussed, and a research agenda is presented.     

Microworlds for experimental research: Having your (control and collection) cake, and realism too

Microworlds (MWs) are dynamic computer-generated environments that subjects interact with in the laboratory and that simulate conditions encountered in the field. Precise levels of experimental control and improved accuracy and efficiency of data collection procedures are characteristic of MWs. It is proposed that these benefits are achieved with concomitant gains in internal validity (afforded by high levels of experimental realism) and external validity (afforded by the replication of the temporal-interactive nature of most field phenomena). To illustrate these ideas, three sets of MW studies are described that investigated rumor and behavior in the stock market (Broker), escalation behavior (Inve$tment Choice$), and the application of foraging theory to internet shopping (Cybershopper).