In this manuscript we study individual variation in the interpretation of conditionals by establishing individual profiles of the participants based on their behavioral responses and reflective attitudes. To investigate the participants’ reflective attitudes we introduce a new experimental paradigm called the Scorekeeping Task, and a Bayesian mixture model tailored to analyze the data. The goal is thereby to identify the participants who follow the Suppositional Theory of conditionals and Inferentialism and to investigate their performance on the uncertain (...) and-to-if inference task. (shrink)

Biologists seems to hold two fundamental beliefs: Organisms are organized into levels and the individuals at these levels differ in their properties. Together these suggest that there will be massive multiple realization, i.e. that many human psychological properties are multiply realized at many neurobiological levels. This paper provides some documentation in support of this suggestion.

Biologists seems to hold two fundamental beliefs: Organisms are organized into levels and the individuals at these levels differ in their properties. Together these suggest that there will be massive multiple realization, i.e. that many human psychological properties are multiply realized at many neurobiological levels. This paper provides some documentation in support of this suggestion.

The target article suggests inter-individual variability is a weakness of microbiota-gut-brain research, but we discuss why it is actually a strength. We comment on how accounting for individual differences can help researchers systematically understand the observed variance in microbiota composition, interpret null findings, and potentially improve the efficacy of therapeutic treatments in future clinical microbiome research.

The paper addresses the capabilities and limitations of extrafoveal processing during a categorical visual search. Previous research has established that a target could be identified from the very first or without any saccade, suggesting that extrafoveal perception is necessarily involved. However, the limits in complexity defining the processed information are still not clear. We performed four experiments with a gradual increase of stimuli complexity to determine the role of extrafoveal processing in searching for the categorically defined geometric shape. The series (...) of experiments demonstrated a significant role of extrafoveal processing while searching for simple two‐dimensional shapes and its gradual decrease in a condition with more complicated three‐dimensional shapes. The factors of objects’ spatial orientation and distractor homogeneity significantly influenced both reaction time and the number of saccades required to identify a categorically defined target. An analysis of the individual p‐value distributions revealed pronounced individual differences in using extrafoveal analysis and allowed examination of the performance of each particular participant. The condition with the forced prohibition of eye movements enabled us to investigate the efficacy of covert attention in the condition with complicated shapes. Our results indicate that both foveal and extrafoveal processing are simultaneously involved during a categorical search, and the specificity of their interaction is determined by the spatial orientation of objects, type of distractors, the prohibition to use overt attention, and individual characteristics of the participants. (shrink)

This study puts the usage-based assumption that our linguistic knowledge is based on usage to the test. To do so, we explore individual variation in speakers’ language use as established based on corpus data – both in terms of frequency of use and productivity of use – and link this variation to the same participants’ responses in an experimental judgment task. The empirical focus is on transfer by native German speakers living in the Netherlands, who oftentimes experience (...) transfer from their second language Dutch to their native language German regarding the placement of prepositional phrases. The analyses show a large amount of variation in both the corpus and experimental data with a strong link across data types: individual speakers’ usage – but not the usage by other speakers – is a significant predictor for the speakers’ judgments. These results strongly suggest that, in line with a usage-based approach, variation between speakers in experimental tasks is linked to their variation in usage. At the same time, such usage-based predictions do not explain all of the variation, suggesting that other individual factors are also at play in such experimental tasks. (shrink)

The concept of animal personality is based on consistent individual differences in behaviour, yet little is known about the factors responsible for such variation. Theory based on sex-specific selection predicts sexual dimorphism in personality-related traits and, in some cases, differences in trait variances between the sexes. In this study, we examined the sources of individual variation for boldness behaviour in guppies (Poecilia reticulata). We first demonstrated heightened boldness expression in males relative to females across feral wild (...) types, artificially selected domestic ‘designer’ guppies, and putative hybrids of the two. Boldness and body size covaried at the strain level but were not associated among individuals within strains. We also found high and repeatable behavioural differences among individuals (0.40 > intraclass r > 0.60) in all sex/strain groups except hybrid strain females. However, there was no evidence for the heightened inter-individual male variance anticipated for personality traits subject to certain forms of directional sex-specific selection. Domestic fish were boldest overall, and indicated the largest sex difference, which is consistent with genetic linkage between boldness and male ornamental colouration. Consistently high intrinsic variation in boldness behaviour, which extends to inbred domesticated fish, may in part underpin the invasive potential of this species. (shrink)

People consistently act in ways that harm the environment, even when believing their actions are environmentally friendly. A case in point is a biased judgment termed the negative footprint illusion, which arises when people believe that the addition of “eco-friendly” items to conventional items, reduces the total carbon footprint of the whole item-set, whereas the carbon footprint is, in fact, increased because eco-friendly items still contribute to the overall carbon footprint. Previous research suggests this illusion is the manifestation of an (...) “averaging-bias.” We present two studies that explore whether people’s susceptibility to the negative footprint illusion is associated with individual differences in: environment-specific reasoning dispositions measured in terms of compensatory green beliefs and environmental concerns; or general analytic reasoning dispositions measured in terms of actively open-minded thinking, avoidance of impulsivity and reflective reasoning. A negative footprint illusion was demonstrated when participants rated the carbon footprint of conventional buildings combined with eco-friendly buildings and conventional cars combined with eco-friendly cars. However, the illusion was not identified in participants’ ratings of the carbon footprint of apples. In Studies 1 and 2, environment-specific dispositions were found to be unrelated to the negative footprint illusion. Regarding reflective thinking dispositions, reduced susceptibility to the negative footprint illusion was only associated with actively open-minded thinking measured on a 7-item scale and 17-item scale. Our findings provide partial support for the existence of a negative footprint illusion and reveal a role of individual variation in reflective reasoning dispositions in accounting for a limited element of differential susceptibility to this illusion. (shrink)

A growth in consumer and media ethical consciousness has resulted in the need for organizations to ensure that members understand, share and project an approved and unified set of ethics. Thus understanding which variables are related to sharing and variation of ethical reasoning and moral intent, and the relative strength of these variables is critical. While past research has examined individual (attitudes, values, etc.), social (peers, significant others, etc.) and organizational (codes of conduct, senior management, etc.) variables, it (...) has focused on their influence on the individual – and not on their role in relation to patterns of group sharing and variation in an organization. Introduced as a new methodology to study ethics, microcultural analysis stipulates that to explain patterns of sharing and variation, one must understand how individual, social and organizational variables influence sharing and variation. Key hypotheses predict that managers who share in individual, social or organizational determinants will be more likely to share in ethical reasoning and moral intent. Qualitative and quantitative research supports the key hypotheses, finding social ties, personal moral intensity, Machiavellianism, locus of control and codes of ethics as significant determinants. Individuals who share in these determinants are more likely to share in ethical reasoning and moral intent. Additionally, regression analysis reveals social ties and personal moral intensity to be the strongest determinants. Based on these results, managerial recommendations focus on a holistic approach, manipulating these three determinants to cultivate a unified code of ethics within an organization. (shrink)

Stanovich & West (S&W) appear to overlook the adaptivity of variation. Behavioral variability, both between and within individuals, is an absolute necessity for phylogenetic and ontological adaptation. As with all heritable characteristics, inter-individual behavioral variation is the foundation for natural selection. Similarly, intra-individual variation allows a broad exploration of potential solutions. Variation increases the likelihood that more optimal behaviors are available for selection. Four examples of the adaptivity of variation are discussed: (a) Genetic (...) variation as it pertains to behavior and natural selection; (b) behavioral and cognitive aspects of mate selection which may facilitate genetic diversity; (c) variation as a strategy for optimizing learning through greater exploration; and (d) behavioral variation coupled with communication as a means to propagate individually discovered behavioral success. (shrink)

This study investigates the extent to which there is individuality in how structural variation is conditioned over time. Earlier research already classified the diachronically unstable gerund variation as involving a high fraction of mixed-usage speakers throughout the change, whereby the proportion of the conservative variant versus the progressive variant as observable in the linguistic output of individual language users superficially resembles the mean proportion as observable at the population level. However, this study sets out to show that (...) there can still be heterogeneity within such a centralized population in terms of how each individual conditions the observed variation. A random forest and conditional inference tree analysis of over 14,000 gerunds uttered by nineteen seventeenth-century authors is presented to show that, while the most important language-internal factors conditioning the gerund variation are adopted by (and shared between) all authors, we can still attest inter-individual variation (i) at lower levels of variable importance, and (ii) in the breadth of the range of contexts individual authors employ to condition the attested variation. (shrink)

Several suggestions are made for revision of Strategic Pluralism Theory (SPT). One revision requires recognition of the impact of individual differences in cognitive and behavioral competence on optimal mating strategy. In addition, SPT may need to incorporate certain self-regulatory processes such as the impact of widespread valuation of mates with one trait on their availability.

The ArgumentEugenics, in whatever form it may be articulated, is based on the idea that phenotypic characteristics of particular individuals can be predicted in advance. This paper argues that biology's capacity to predict many of the characteristics exhibited by an individual, especially behavioral or cognitive attributes, will always be very limited. This stems from intrinsic limitations to the methodology for relating genotypes to phenotypes, and from the nature of developmental processes which intervene between genotypes and phenotypes. While genetic studies (...) may generate valid population predictions for conditions which impact human health, neither genetics nor developmental biology are likely to generate useful individual predictions about variation in non-disease-related human behavioral and cognitive phenotypes in the foreseeable future. (shrink)

S’interroger sur les variations intra-individuelles des comportements culturels, et notamment chercher à saisir les variations du degré de légitimité culturelle des goûts et des pratiques, selon le domaine ou le type de pratique considéré, permet de respecter un peu plus que d’ordinaire la complexité des patrimoines de dispositions et de compétences culturelles individuels. Mais la construction de profils culturels individuels rend nécessaire un retour réflexif sur les présupposés des habitudes intellectuelles qui consistent : 1) à agréger des individus dans des (...) groupes ou des catégories sur la base de propriétés communes ; 2) à lister les traits les plus fréquemment attachés statistiquement à ces groupes ou à ces catégories et 3) à brosser un portrait idéaltypique du groupe et de sa culture.Examining intra-individual variations of cultural behaviours, and in particular the varying degrees of cultural legitimacy of tastes and practices according to the sphere or type of practice considered, is a way of showing more than the usual respect for the complexity of individual inheritances of cultural dispositions and competences. But the construction of individual cultural profiles makes it necessary to look closer at the underlying assumptions of some intellectual habits. These consist of : 1) aggregating individuals in categories or groups on the basis of common properties ; 2) listing the features most frequently associated statistically with these categories or groups and 3) painting an idealtypical portrait of the group and its culture. (shrink)

Because they involve individual-level cognitive processes, psychological explanations of linguistic phenomena are in principle testable against individual behaviour. The present study draws on patterns of individual variation in corpus data to test explanations of productivity. Linguistic patterns are predicted to become more productive with higher type frequencies and lower token frequencies. This is because the formation of abstract mental representations is encouraged by varied types but counteracted by automation of high-frequency types. The predictions are tested for (...) English -ly and -ness-derivation, as used by 698 individual journalists in the New York Times Annotated Corpus and 171 members of Parliament in the Hansard Corpus. Linear regression is used to model individual variation in productivity, in relation to type and token frequency, as well as several other predictor variables. While the expected effects are observed, there is also robust evidence of an interaction effect between type and token frequency, indicating that productivity is highest for patterns with many types and not-too-infrequent tokens. This fits best with a view of entrenchment as both a conservative and creative force in language. Further, some variation remains irreducibly individual and is not explained by currently known predictors of productivity. (shrink)

This issue assesses how human spatial navigation differs: within individuals across short‐term variations in mood or stress, and between individuals across variations in age, gender, education, culture, and physical environment.

This study in Bangladesh found that inter-cluster variation in the use of modern reversible methods of contraception was significantly attributable to the educational levels of the female family planning workers working in the clusters. Women belonging to clusters served by educated workers had a higher probability of being contraceptive users than those whose workers had only completed primary education. At the household level, important determinants of use were socioeconomic status and religion. At the individual level, the woman being (...) the wife of the household head and having some education were positively related to her being a user. The model also found that inter-household variation was significantly greater than inter-cluster variation. Finally, the study concludes that after controlling for various covariates at all three levels, the clusters do not have significantly different levels of use of modern reversible methods of contraception. There are, however, some special areas where contraceptive use is dramatically low, and these contribute significantly to the observed inter-cluster variation. (shrink)

Studies show that there are widespread intrasubjective and intersubjective color variations among normal perceivers. These variations have serious ramifications in the debate about the nature and ontology of color. It is typical to think of the debate about color as a dispute between objectivists and subjectivists. Objectivists hold that colors are perceiver-independent physical properties of objects while subjectivists hold that they are either projections onto external objects or dispositions objects have to look colored. I argue that individual color variations (...) present difficulties, albeit not the same kind, for both objectivism and subjectivism. Lastly, I propose an alternative account that handles such variations nicely. (shrink)

Longitudinal qualitative research in nursing is rare but becoming more common. Data collection and analysis over time provide some intriguing possibilities to better understand processes, development, and change in illness experience, healthcare organizations, and self‐management. This paper aims to present a process for analyzing qualitative longitudinal data material, namely the Pattern‐Oriented Longitudinal Analysis approach (POLA). We developed this approach after synthesizing experiences from two longitudinal qualitative projects and comparing our procedures and reflections with the relevant literature. Using the POLA approach, (...) researchers can describe complexity and variation in changes over time. During the analysis process, emphasis is put on visualizing and identifying change at both an individual and a group level. Ontological and epistemological assumptions for the approach are also described. The benefit of this approach is the possibility to describe complexity and diversity in processes over time, which is important for the development of nursing knowledge. The analysis approach can be further used and developed by researchers seeking to understand variance or contextual features in processes and changes over time. (shrink)

There is a growing appreciation of the extent of transcriptome variation across individual cells of the same cell type. While expression variation may be a byproduct of, for example, dynamic or homeostatic processes, here we consider whether single‐cell molecular variation per se might be crucial for population‐level function. Under this hypothesis, molecular variation indicates a diversity of hidden functional capacities within an ensemble of “identical” cells, and this functional diversity facilitates collective behavior that would be (...) inaccessible to a homogenous population. In reviewing this topic, we explore possible functions that might be carried by a heterogeneous ensemble of cells; however, this question has proven difficult to test, both because methods to manipulate molecular variation are limited and because it is complicated to define, and measure, population‐level function. We consider several possible methods to further pursue the hypothesis that “variation is function” through the use of comparative analysis and novel experimental techniques. (shrink)

The paper examines definitions of ‘cause’ in the epidemiological literature. Those definitions all describe causes as factors that make a difference to the distribution of disease or to individual health status. In the philosophical jargon, causes in epidemiology are difference-makers. Two claims are defended. First, it is argued that those definitions underpin an epistemology and a methodology that hinge upon the notion of variation, contra the dominant Humean paradigm according to which we infer causality from regularity. Second, despite (...) the fact that causes be defined in terms of ‘difference-making’, this cannot fixes the causal metaphysics. Causality in epidemiology ought to be interpreted according to the epistemic theory. In this approach relations are deemed causal depending on the evidence and on the available methods. Indeed, evidence to establish causal claims requires difference-making considerations; furthermore, those definitions of cause reflect the ‘variational’ epistemology and methodology of epidemiology. (shrink)

Most psychological research aims to uncover generalizations about the mind that hold across subjects. Philosophical discussions of scientific explanation have focused on such generalizations, but in doing so, have often overlooked an important phenomenon: variation. Variation is ubiquitous in psychology and many other domains, and an important target of explanation in its own right. Here I characterize explananda that concern individual differences and formulate an account of what it takes to explain them. I argue that the notion (...) of actual difference making, the only causal concept in the literature that explicitly addresses variation, cannot be used to ground such an account. Instead, I propose a view on which explaining individual differences involves identifying causes that could be intervened on to reduce the variability in the population. This account provides criteria of success for explaining variation and deepens our understanding of causal explanation. (shrink)

Animal personality refers to the consistency of variation in behavior among individuals which may be the driving force behind variations in complex behaviors as well. Individual personality could predict how well an organism would perform in behavior and cognition related tasks, as well as survive and thrive in its environment. Therefore, we would expect inter-individual variations in many behaviors, which would persist even if habituation to the experimental setup occurs, which generally results in convergence of behavior. Our (...) study used wild-caught zebrafish from three natural habitats with differing ecological regimes, to understand how consistency and repeatability in specific traits such as boldness, exploration, and spatial ability varies across and within populations even when habituation causes change in behavior. We found that the extent of individual variation differs between populations, with dynamic habitats showing similar repeatability. This indicates that habitat conditions are important drivers of individual variation in addition to other factors, such as sex or size of individuals within populations. Although we found that sex and size played an important role within some populations for some behaviors, in others, the variation was likely caused by other factors, for which we have not accounted. This study underlines the importance of studying inter-individual differences as the phenomenon that underpins multiple behavioral traits and explains the possible role of environmental and inherent factors that drive these differences. (shrink)

Investigation of neural and cognitive processes underlying individual variation in moral preferences is underway, with notable similarities emerging between moral- and risk-based decision-making. Here we specifically assessed moral distributive justice preferences and non-moral financial gambling preferences in the same individuals, and report an association between these seemingly disparate forms of decision-making. Moreover, we find this association between distributive justice and risky decision-making exists primarily when the latter is assessed with the Iowa Gambling Task. These findings are consistent with (...) neuroimaging studies of brain function during moral and risky decision-making. This research also constitutes the first replication of a novel experimental measure of distributive justice decision-making, for which individual variation in performance was found. Further examination of decision-making processes across different contexts may lead to an improved understanding of the factors affecting moral behaviour. (shrink)

The impressive variation amongst biological individuals generates many complexities in addressing the simple-sounding question what is a biological individual? A distinction between evolutionary and physiological individuals is useful in thinking about biological individuals, as is attention to the kinds of groups, such as superorganisms and species, that have sometimes been thought of as biological individuals. More fully understanding the conceptual space that biological individuals occupy also involves considering a range of other concepts, such as life, reproduction, and agency. (...) There has been a focus in some recent discussions by both philosophers and biologists on how evolutionary individuals are created and regulated, as well as continuing work on the evolution of individuality. (shrink)

Background: Research has shown important between-individual variations in physical activity during the COVID-19 lockdown.Objectives: The objectives of this is study are to examine the individual, sociodemographic, and environmental factors related to PA during the spring 2020 COVID-19 lockdown in France and to explore the mediating and moderating role of intention and self-efficacy toward PA in the relationships between sociodemographic/environmental variables and PA.Design: In this cross-sectional study, participants living in France completed an online survey between March 30 and April (...) 10, 2020.Method: Minutes per week of moderate-to-vigorous PA during the lockdown; usual physical activity before the lockdown; and psychological, sociodemographic, and environmental factors were measured in the survey. Multiple linear regressions were used to investigate the role of these predictors on PA. Intention and self-efficacy were also examined as moderators and mediators of the association between sociodemographic/environmental factors and PA.Results: Usual physical activity before the COVID-19 lockdown, intention toward PA, habitat surface area, and controlled motivation significantly predicted PA during the lockdown. No mediating effects of intention or self-efficacy were found. Intention significantly moderated the association between gender and PA and the association between part-time work and PA.Conclusions: PA during the COVID-19 lockdown was mainly predicted by individual factors and notably usual PA. These results highlight the important role of habits in a highly changing context. (shrink)

When the side effect of an action involves moral considerations (e.g. when a chairman’s pursuit of profits harms the environment) it tends to influence theory-of-mind judgments. On average, bad side effects are judged intentional whereas good side effects are judged unintentional. In a series of two experiments, we examined the largely uninvestigated roles of individual differences in this judgment asymmetry. Experiment 1 indicated that extraversion accounted for variations in intentionality judgments, controlling for a range of other general individual (...) differences (e.g. working memory, self-control). Experiment 2 indicated that extraversion’s influence was partially mediated by more specific variations in intentional action concepts. A priming manipulation also provided causal evidence of judgment instability and bias. Results suggest that the intentional action judgment asymmetry is multiply determined, reflecting the interplay of individual differences and judgment biases. Implications and the roles of individual differences in judgment and decision-making research are discussed. (shrink)

Working memory--the ability to keep important information in mind while comprehending, thinking, and acting--varies considerably from person to person and changes dramatically during each person's life. Understanding such individual and developmental differences is crucial because working memory is a major contributor to general intellectual functioning. This volume offers a state-of-the-art, integrative, and comprehensive approach to understanding variation in working memory by presenting explicit, detailed comparisons of the leading theories. It incorporates views from the different research groups that operate (...) on each side of the Atlantic, and covers working-memory research on a wide variety of populations, including healthy adults, children with and without learning difficulties, older adults, and adults and children with neurological disorders. A particular strength of this volume is that each research group explicitly addresses the same set of theoretical questions, from the perspective of both their own theoretical and experimental work and from the perspective of relevant alternative approaches. Through these questions, each research group considers their overarching theory of working memory, specifies the critical sources of working memory variation according to their theory, reflects on the compatibility of their approach with other approaches, and assesses their contribution to general working memory theory. This shared focus across chapters unifies the volume and highlights the similarities and differences among the various theories. Each chapter includes both a summary of research positions and a detailed discussion of each position. Variation in Working Memory achieves coherence across its chapters, while presenting the entire range of current theoretical and experimental approaches to variation in working memory. (shrink)

We do not all make choices, reason, interpret our experience, or respond to our environment in the same way. A recent surge of scientific interest has thrust these individual differences into the spotlight: researchers in cognitive psychology and neuroscience are now devoting increasing attention to cognitive variation. The philosophical dimensions of this research, however, have yet to be systematically explored. Here I make an initial foray by considering how cognitive variation is characterized. I present a central dilemma (...) facing descriptions of individual differences, discuss several distinctions used to categorize variation, and show that these distinctions require further elaboration. Finally, by canvassing several philosophical topics for which the characterization of cognitive variation may have significant implications, I argue that philosophers should take note of how and why our minds differ. (shrink)

Malaria is a Plasmodium parasitic disease transmitted by infected female Anopheles mosquitoes. Climatic factors, such as temperature, humidity, rainfall, and wind, have significant effects on the incidence of most vector-borne diseases, including malaria. The mosquito behavior, life cycle, and overall fitness are affected by these climatic factors. This paper presents the results obtained from investigating the optimal control strategies for malaria in the presence of temperature variation using a temperature-dependent malaria model. The study further identified the temperature ranges in (...) four different geographical regions of sub-Saharan Africa, suitable for mosquitoes. The optimal control strategies in the temperature suitable ranges suggest, on average, a high usage of both larvicides and adulticides followed by a moderate usage of personal protection such as bednet. The average optimal bednet usage mimics the solution profile of the mosquitoes as the mosquitoes respond to changes in temperature. Following the results from the optimal control, this study also investigates using a temperature-dependent model with insecticide-sensitive and insecticide-resistant mosquitoes the impact of insecticide-resistant mosquitoes on disease burden when temperature varies. The results obtained indicate that optimal bednet usage on average is higher when insecticide-resistant mosquitoes are present. Besides, the average bednet usage increases as temperature increases to the optimal temperature suitable for mosquitoes, and it decreases after that, a pattern similar to earlier results involving insecticide-sensitive mosquitoes. Thus, personal protection, particularly the use of bednets, should be encouraged not only at low temperatures but particularly at high temperatures when individuals avoid the use of bednets. Furthermore, control and reduction of malaria may be possible even when mosquitoes develop resistance to insecticides. (shrink)

Background Intestinal transplant in infants with severe short bowel syndrome (SBS) is an emerging therapy, yet without sufficient long-term data or established guidelines, resulting in possible variation in practice. Objectives To assess current attitudes and counselling practices among physicians regarding intestinal transplant in infants with SBS, and to determine whether counselling and management vary between subspecialists or centres. Methods A national sample of practicing paediatric surgeons and neonatologists was surveyed via the American Academy of Paediatrics listserves. Results were analysed (...) by physician subspecialty and again by presence or absence of intestinal transplant at respondent's centre. Results The survey was completed by 433 respondents, consisting of 363 neonatologists and 70 paediatric surgeons. Fifty-seven respondents (13.2%) practiced at a centre that performed intestinal transplants in children. The vast majority of respondents (91% for preterm, 95% for term neonates) felt that maintaining a neonate with SBS on total parenteral nutrition for intestinal transplant was ethically optional (neither impermissible nor obligatory), and that parents should be given an informed choice whether to pursue that option. However, only 33% indicated they often/always offer intestinal transplant as a treatment option to families in this situation. Conclusions There is a marked disparity between individual physicians’ beliefs regarding the acceptability of intestinal transplant for severe SBS and their reported practice. Wide variability exists among physicians with respect to their knowledge, beliefs and practice regarding severe SBS, raising concerns about transparency and justice. Survival data prior to transplant, currently unavailable, are essential to rational decision making and informed parental permission. (shrink)

Résumé : Le stage d’enseignement est fréquemment considéré comme une période particulièrement propice au développement de la pratique réflexive. Souhaitant contribuer à cette réflexion, l’objectif de cet article vise à mieux comprendre la variation de la pratique réflexive des enseignants-stagiaires suivant les contextes académique et pratique. Pour ce faire, nous présentons une recherche qualitative, dont l’analyse thématique d’entrevues nous a permis de relever des variations contextuelles de la pratique réflexive à trois niveaux distincts : la motivation et la finalité (...) ; les acteurs soutenant la pratique réflexive ; enfin, les modalités d’interaction entre les acteurs. Abstract : Teaching practicum is usually considered as pivotal in the development of reflective practice. This article seeks to contribute to this reflexion in aiming to better understand how reflective practice varies between academic and practical contexts. In order to reach this objective, we proceeded to individual and group interviews with three groups of preservice teachers during their practicum. The content analysis that emerged shows that reflective practice varies at three different levels between academic and practical contexts: motivation and purpose; actors supporting reflective practice during practicum; interaction between actors. (shrink)

BackgroundConventionally, transcranial direct current stimulation (tDCS) aims to focalize the current reaching the target region-of-interest (ROI). The focality can be quantified by the dose-target-determination-index (DTDI). Despite having a uniform tDCS setup, some individuals receive focal stimulation (high DTDI) while others show reduced focality (“non-focal”). The volume of cerebrospinal fluid (CSF), gray matter (GM), and white matter (WM) underlying each ROI govern the tDCS current distribution inside the brain, thereby regulating focality.AimTo determine the regional volume parameters that differentiate the focal and (...) non-focal groups.MethodsT1-weighted images of the brain from 300 age-sex matched adults were divided into three equal groups- (a) Young (20 ≤ × < 40 years), (b) Middle (40 ≤ × < 60 years), and (c) Older (60 ≤ × < 80 years). For each group, inter and intra-hemispheric montages with electrodes at (1) F3 and right supraorbital region (F3-RSO), and (2) CP5 and Cz (CP5-Cz) were simulated, targeting the left- Dorsolateral Prefrontal Cortex (DLPFC) and -Inferior Parietal Lobule (IPL), respectively. Both montages were simulated for two current doses (1 and 2 mA). For each individual head simulated for a tDCS configuration (montage and dose), the current density at each region-of-interest (ROI) and their DTDI were calculated. The individuals were categorized into two groups- (1) Focal (DTDI ≥ 0.75), and (2) Non-focal (DTDI < 0.75). The regional volume of CSF, GM, and WM of all the ROIs was determined. For each tDCS configuration and ROI, three 3-way analysis of variance was performed considering- (i) GM, (ii) WM, and (iii) CSF as the dependent variable (DV). The age group, sex, and focality group were the between-subject factors. For a given ROI, if any of the 3 DV’s showed a significant main effect or interaction involving the focality group, then that ROI was classified as a “focal ROI.”ResultsRegional CSF was the principal determinant of focality. For interhemispheric F3-RSO montage, interaction effect (p < 0.05) of age and focality was observed at Left Caudate Nucleus, with the focal group exhibiting higher CSF volume. The CSF volume of focal ROI correlated positively (r ∼ 0.16, p < 0.05) with the current density at the target ROI (DLPFC). For intrahemispheric CP5-Cz montage, a significant (p < 0.05) main effect was observed at the left pre- and post-central gyrus, with the focal group showing lower CSF volume. The CSF volume correlated negatively (r ∼ –0.16, p < 0.05) with current density at left IPL. The results were consistent for both current doses.ConclusionThe CSF channels the flow of tDCS current between electrodes with focal ROIs acting like reservoirs of current. The position of focal ROI in the channel determines the stimulation intensity at the target ROI. For focal stimulation in interhemispheric F3-RSO, the proximity of focal ROI reserves the current density at the target ROI (DLPFC). In contrast, for intrahemispheric montage (CP5-Cz), the far-end location of focal ROI reduces the current density at the target (IPL). (shrink)