Search results for "adaptive strategies"
showing 10 items of 11 documents
The Associations of Activity Fragmentation with Physical and Mental Fatigability among Community-Dwelling 75-, 80- and 85-Year-Old People
2020
Abstract Background Fatigue related to task standardized by duration and intensity, termed fatigability, could manifest as shortening of activity bouts throughout the day causing daily activity to accumulate in a more fragmented pattern. Our purpose was to study the association of activity fragmentation with physical and mental dimensions of fatigability. Methods A cross-sectional study of 485 community-dwelling 75-, 80-, and 85-year-old people using a thigh-worn accelerometer for 3–7 days. Activity fragmentation was studied as Active-to-Sedentary Transition Probability for 2 operational definitions of physical activity: accelerations equivalent to at least light physical activity and for u…
Individual differences in adaptive choice strategies
2003
Abstract Individual differences in compensatory and non-compensatory choice processes remain an unresolved issue for decision process researchers. This study investigates the stability and nature of individual differences in choice processes when individuals adapt to changes in the structure of the choice environment, namely the correlation among the choice attributes. By means of process tracing techniques, between-subjects differences in choice processing (option-based or attribute based) were found to be stable across different tasks. Individuals with higher openness to experience and ability to solve reasoning tasks were found to be more adaptive, that is to switch more promptly their c…
New behavioural trait adopted or rejected by observing heterospecific tutor fitness
2010
Animals can acquire behaviours from others, including heterospecifics, but should be discriminating in when and whom to copy. Successful individuals should be preferred as tutors, while adopting traits of poorly performing individuals should be actively avoided. Thus far it is unknown if such adaptive strategies are involved when individuals copy other species. Furthermore, rejection of traits based on tutor characteristics (negative bias) has not been shown in any non-human animal. Here we test whether a choice between two new, neutral behavioural alternatives—breeding-sites with alternative geometric symbols—is affected by observing the choice and fitness of a heterospecific tutor. A fiel…
Active and inactive quarantine in epidemic spreading on adaptive activity-driven networks
2020
We consider an epidemic process on adaptive activity-driven temporal networks, with adaptive behaviour modelled as a change in activity and attractiveness due to infection. By using a mean-field approach, we derive an analytical estimate of the epidemic threshold for SIS and SIR epidemic models for a general adaptive strategy, which strongly depends on the correlations between activity and attractiveness in the susceptible and infected states. We focus on strong social distancing, implementing two types of quarantine inspired by recent real case studies: an active quarantine, in which the population compensates the loss of links rewiring the ineffective connections towards non-quarantining …
Implicit Learning in Children Is Not Related to Age: Evidence from Drawing Behavior
2000
Three experiments are reported on implicit learning in 432 children between the ages of 4 and 10 years, using a new paradigm ("the neutral parameter procedure") based on drawing behavior. The first two experiments demonstrated that children modified their drawing behavior following specially devised practice in such a way that these modifications could not be viewed as the result of deliberate adaptive strategies. The third experiment showed that these behavioral modifications lasted for at least 1 hr after the training phase. No age-related differences appeared in the experiments. A comparison of children's data with similar adults' data also failed to reveal any age differences. These res…
Adaptive strategies of territory formation
2003
How do territorial animals gain ownership of an area? Early modelling has considered the evolution of fighting when the winner can claim the right to the resource. Recently, alternative hypotheses have been offered where repeated interactions lead to division of space through 'nagging' instead of one decisive fight. However, these models assume that animals avoid areas in which they have taken part in aggressive interactions, but do not consider whether avoidance itself is adaptive. We aim to bridge this gap between mechanistic and adaptive explanations, by presenting a game-theory model where individuals choose whether to return to an area after a fight with a specific outcome (win, loss, …
Serotoninergic Modulation of Phototactic Variability Underpins a Bet-Hedging Strategy in Drosophila melanogaster
2021
When organisms’ environmental conditions vary unpredictably in time, it can be advantageous for individuals to hedge their phenotypic bets. It has been shown that a bet-hedging strategy possibly underlies the high inter-individual diversity of phototactic choice in Drosophila melanogaster. This study shows that fruit flies from a population living in a boreal and relatively unpredictable climate have more variable variable phototactic biases than fruit flies from a more stable tropical climate, consistent with bet-hedging theory. We experimentally show that phototactic variability of D. melanogaster is regulated by the neurotransmitter serotonin (5-HT), which acts as a suppressor of the var…
Birds facing climate change: a qualitative model for the adaptive potential of migratory behaviour
2015
Recent climate change is altering the migratory behaviour of many bird species. An advancement in the timing of spring events and a shift in the geographical distribution have been detected for birds around the world. In particular, intra-Palearctic migratory birds have advanced arrivals in spring and shortened migratory distances by shifting northward their wintering grounds. These changes in migratory patterns are considered adaptive responses facilitating the adjustment of the life cycle to the phenological changes found in their breeding areas. However, in some cases, populations exposed to the same selective pressures do not show any appreciable adaptive change in their behaviour. Basi…
Examining five pathways on how self-control is associated with emotion regulation and affective well-being in daily life.
2020
OBJECTIVE Self-control is positively connected to well-being, but less is known about what, on the mechanistic level, explains this association. We hypothesized five pathways how this connection could be explained by emotion regulation, that is, by facilitating (a) strategy effectiveness, (b), adaptive strategy selection, (c) situation selection, (d) strategy variability, or (e) social sharing. METHOD To explore these pathways, we integrated two ambulatory assessment data sets (N = 250 participants, N = 22,796 observations) that included assessments of participants' emotions and their emotion regulation efforts. RESULTS We found that self-control was positively associated with affective wel…
An efficient adaptive strategy for searching in peer-to-peer networks
2005
One of the main technical challenges in Peer-to-Peer (P2P) networks is how to efficiently locate desired resources. Although structured systems, based on distributed hash tables, can achieve fair effectiveness, they are not suitable for widely deployed Internet applications. In fact, this kind of systems shows many severe limitations, such as ignoring the autonomous nature of peers, and supporting only weakly semantic functions. Unstructured P2P networks are more attractive for real applications, since they can avoid both the limitations of centralized systems, and the drawbacks of structured approaches. However, their search algorithms are usually based on inefficient flooding schemes, tha…