Judgments about objects in the world are often based on probabilistic information (or cues). A frugal judgment strategy that utilizes memory (i.e., the ability to discriminate between known and ...unknown objects) as a cue for inference is the recognition heuristic (RH). The usefulness of the RH depends on the structure of the environment, particularly the predictive power (validity) of recognition. Little is known about developmental differences in use of the RH. In this study, the authors examined (a) to what extent children and adolescents recruit the RH when making judgments, and (b) around what age adaptive use of the RH emerges. Primary schoolchildren (M = 9 years), younger adolescents (M = 12 years), and older adolescents (M = 17 years) made comparative judgments in task environments with either high or low recognition validity. Reliance on the RH was measured with a hierarchical multinomial model. Results indicated that primary schoolchildren already made systematic use of the RH. However, only older adolescents adaptively adjusted their strategy use between environments and were better able to discriminate between situations in which the RH led to correct versus incorrect inferences. These findings suggest that the use of simple heuristics does not progress unidirectionally across development but strongly depends on the task environment, in line with the perspective of ecological rationality. Moreover, adaptive heuristic inference seems to require experience and a developed base of domain knowledge.
Value‐based decisions often involve comparisons between benefits and costs that must be retrieved from memory. To investigate the development of value‐based decisions, 9‐ to 10‐year olds (N = 30), ...11‐ to 12‐year olds (N = 30), and young adults (N = 30) first learned to associate gain and loss magnitudes with symbols. In a subsequent decision task, participants rapidly evaluated objects that consisted of combinations of these symbols. All age groups achieved high decision performance and were sensitive to gain–loss magnitudes, suggesting that required core cognitive abilities are developed early. A cognitive‐modeling analysis of performance revealed that children were less efficient in object evaluation (drift rate) and had longer nondecision times than adults. Developmental differences, which emerged particularly for objects of high positive net value, were linked to mnemonic and numerical abilities.
Abstract
Objectives
Changes in motivational orientation across adulthood affect cognitive processes. The purpose of this research was to investigate if and how motivational incentives (gains or ...losses) affect prospective memory for intended actions in younger, middle-aged, and older adults.
Methods
The consequences of memory hits and misses and the framing of the memory tasks were experimentally manipulated between participants: In a gain-framing condition, participants accumulated rewards, dependent on the proportion of target events to which they responded accurately. In a loss-framing condition, participants received an initial endowment from which losses were deducted, dependent on the proportion of targets they missed. We measured memory accuracy, perceived task importance, and ongoing-task performance.
Results
Gains and losses had different effects on memory across age groups: Age × Motivational Valence interactions emerged across two studies. Older adults showed relatively better memory performance to avoid losses than to achieve gains. Moreover, higher age was associated with lower memory performance (Study 1) and slower but more accurate decisions in an ongoing activity (Study 2).
Discussion
The findings reveal that motivational incentives and the framing of consequences as gains or losses moderate the relation between age and memory performance. Older adults’ memory performance may benefit when messages encourage the avoidance of losses. This may also help to design age-tailored interventions in applied settings (e.g., health-related behavior).
This research addresses how younger and older adults' decisions and evaluations of gains and losses are affected by the way in which monetary incentives are provided. We compared 2 common incentive ...schemes in decision making: pay one (only a single decision is incentivized) and pay all (incentives across all decisions are accumulated).
Younger adults (18-36 years; n = 147) and older adults (60-89 years; n = 139) participated in either a pay-one or pay-all condition and made binary choices between two-outcome monetary lotteries in gain, loss, and mixed domains. We analyzed participants' decision quality, risk taking, and psychometric test scores. Computational modeling of cumulative prospect theory served to measure sensitivity to outcomes and probabilities, loss aversion, and choice sensitivity.
Decision quality and risk aversion were higher in the gain than mixed or loss domain, but unaffected by age. Loss aversion was higher, and choice sensitivity was lower in older than younger adults. In the pay-one condition, the value functions were more strongly curved, and choice sensitivity was higher than in the pay-all condition.
An opportunity of accumulating incentives has similar portfolio effects on younger and older adults' decisions. In general, people appear to decide less cautiously in pay-all than pay-one scenarios. The impact of different incentive schemes should be carefully considered in aging and decision research.
Increased nitrogen (N) depositions expected in the future endanger the diversity and stability of ecosystems primarily limited by N, but also often co‐limited by other nutrients like phosphorus (P). ...In this context a nutrient manipulation experiment (NUMEX) was set up in a tropical montane rainforest in southern Ecuador, an area identified as biodiversity hotspot. We examined impacts of elevated N and P availability on arbuscular mycorrhizal fungi (AMF), a group of obligate biotrophic plant symbionts with an important role in soil nutrient cycles. We tested the hypothesis that increased nutrient availability will reduce AMF abundance, reduce species richness and shift the AMF community toward lineages previously shown to be favored by fertilized conditions. NUMEX was designed as a full factorial randomized block design. Soil cores were taken after 2 years of nutrient additions in plots located at 2000 m above sea level. Roots were extracted and intraradical AMF abundance determined microscopically; the AMF community was analyzed by 454‐pyrosequencing targeting the large subunit rDNA. We identified 74 operational taxonomic units (OTUs) with a large proportion of Diversisporales. N additions provoked a significant decrease in intraradical abundance, whereas AMF richness was reduced significantly by N and P additions, with the strongest effect in the combined treatment (39% fewer OTUs), mainly influencing rare species. We identified a differential effect on phylogenetic groups, with Diversisporales richness mainly reduced by N additions in contrast to Glomerales highly significantly affected solely by P. Regarding AMF community structure, we observed a compositional shift when analyzing presence/absence data following P additions. In conclusion, N and P additions in this ecosystem affect AMF abundance, but especially AMF species richness; these changes might influence plant community composition and productivity and by that various ecosystem processes.
Younger children’s free recall from episodic memory is typically less organized than recall by older children. To investigate if and how repeated learning opportunities help children use ...organizational strategies that improve recall, the authors analyzed category clustering across four study‐test cycles. Seven‐year‐olds, 10‐year‐olds, and young adults (N = 150) studied categorically related words for a free‐recall task. The cognitive processes underlying recall and clustering were measured with a multinomial model. The modeling revealed that developmental differences emerged particularly in the rate of learning to encode words as categorical clusters. The learning curves showed a common pattern across age groups, indicating developmental invariance. Memory for individual items also contributed to developmental differences and was the only factor driving 7‐year‐olds’ moderate improvements in recall.
Arbuscular mycorrhizal fungi (AMF) are crucial to plants and vice versa, but little is known about the factors linking the community structure of the two groups. We investigated the association ...between AMF and the plant community structure in the nearest neighborhood of Festuca brevipila in a semiarid grassland with steep environmental gradients, using high-throughput sequencing of the Glomeromycotina (former Glomeromycota). We focused on the Passenger, Driver and Habitat hypotheses: (i) plant communities drive AMF (passenger); (ii) AMF communities drive the plants (driver); (iii) the environment shapes both communities causing covariation. The null hypothesis is that the two assemblages are independent and this study offers a spatially explicit novel test of it in the field at multiple, small scales. The AMF community consisted of 71 operational taxonomic units, the plant community of 47 species. Spatial distance and spatial variation in the environment were the main determinants of the AMF community. The structure of the plant community around the focal plant was a poor predictor of AMF communities, also in terms of phylogenetic community structure. Some evidence supports the passenger hypothesis, but the relative roles of the factors structuring the two groups clearly differed, leading to an apparent decoupling of the two assemblages at the relatively small scale of this study. Community phylogenetic structure in AMF suggests an important role of within-assemblage interactions.
Motivational and emotional changes across adulthood have a profound impact on cognition. In this registered report, we conducted an experimental investigation of motivational influence on remembering ...intentions after a delay (prospective memory; PM) in younger, middle-aged, and older adults, using gain- and loss-framing manipulations. The present study examined for the first time whether motivational framing in a PM task has different effects on younger and older adults' PM performance (N = 180; age range: 18-85 years) in a controlled laboratory setting. Based on lifespan theories of motivation, we assumed that the prevention of losses becomes more relevant with increasing age: We expected that older adults show relatively higher PM performance in a task with loss-related consequences following PM failure than in a task in which successful PM leads to gains. The opposite pattern of performance was expected for younger adults. The findings suggest that the relevance of reward and positive gain-related consequences for successful remembering appears to decrease with age. As hypothesised, a motivational framing × age interaction indicated that age differences in memory performance were smaller with loss-related than gain-related consequences, supporting a loss-prevention view on motivated cognition.
Celotno besedilo
Dostopno za:
BFBNIB, DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, UILJ, UKNU, UL, UM, UPUK
Time-based prospective memory (TBPM) involves remembering to perform actions at specific times in the future. Several studies suggest that monetary consequences improve prospective remembering; ...however, the effect of monetary consequences on strategic time monitoring (i.e., clock-checking behaviour) in TBPM is still unknown. The present study investigated how the monetary costs on clock-checking affected TBPM accuracy and strategic time monitoring. Participants performed an ongoing lexical decision task while carrying out a TBPM task every two minutes. Motivational incentives were manipulated across three experimental conditions: a single-cost condition in which missed TBPM responses led to monetary deductions, a double-cost condition in which both missed responses and time monitoring led to monetary deductions, and a control condition with no monetary deductions. Overall, the findings indicated that monetary costs on clock-checking prompted more parsimonious strategic time monitoring behaviour, which negatively impacted TBPM accuracy. These results emphasize the importance of weighing the motivational aspects involved in strategic monitoring, shedding light on the complex relationship between clock-checking behaviour, its consequences, and TBPM performance.
Understanding how people of different ages decide in competition is a question of theoretical and practical importance. Using an experimental laboratory approach, this research investigates the ...ability of younger and older adults to think and act strategically with equal or unequal resources. In zero-sum games of resource allocation, younger adults (19-35 years) and older adults (65-81 years) made strategic decisions in competition against opponents of a similar age (Study 1; N = 120) or different age (Study 2; N = 120). The findings highlight people's ability to make good interpersonal decisions in complex scenarios: Both younger and older adults were aware of their relative strength (in terms of material resources) and allocated their resources adaptively. When competing against opponents of a similar age, people's gains were in line with game-theoretic predictions. However, younger adults made superior strategic allocations and won more frequently when competing against older adults. Measures of fluid cognitive and numerical abilities correlated with strategic behavior in interpersonal competition.
PDF
