41 research outputs found

    Gaussian multiplicative chaos through the lens of the 2D Gaussian free field

    Full text link
    The aim of this review-style paper is to provide a concise, self-contained and unified presentation of the construction and main properties of Gaussian multiplicative chaos (GMC) measures for log-correlated fields in 2D in the subcritical regime. By considering the case of the 2D Gaussian free field, we review convergence, uniqueness and characterisations of the measures; revisit Kahane's convexity inequalities and existence and scaling of moments; discuss the measurability of the underlying field with respect to the GMC measure and present a KPZ relation for scaling exponents.Comment: 28p, less typos in the 3rd, published version, still no figures, I remain thankful for comment

    A matter of design: priming context and person perception

    Full text link
    A matter of considerable debate is whether people spontaneously use categorical knowledge (i.e., stereotypes) to guide their interactions with others. Despite initial evidence for the unconditional automaticity of category activation, recent research has identified a range of factors that moderate this process. Extending this line of inquiry, the current investigation explored the extent to which contextual influences - specifically the order in which priming stimuli are presented to participants - may modulate person categorization. Using a standard semantic-priming paradigm to index category and stereotype activation, participants were presented with priming stimuli that were either intermixed or blocked by sex. The results revealed that: (i) category and stereotype activation are moderated by the order in which priming stimuli are presented; and (ii) priming effects decrease monotonically as a function of category repetition. The theoretical implications of these findings are considered

    Investigating the Early Stages of Person Perception: The Asymmetry of Social Categorization by Sex vs. Age

    Get PDF
    The wealth of information provided by facial cues presents challenges to our understanding of these early stages of person perception. The current study aimed to uncover the dynamics of processing multiply categorizable faces, notably as a function of their gender and age. Using a modified four-choice version of a mouse-tracking paradigm (which assesses the relative dominance of two categorical dimensions), the relative influence that sex and age have on each other during categorization of infant, younger adult, and older adult faces was investigated. Results of these experiments demonstrate that when sex and age dimensions are simultaneously categorized, only for infant faces does age influence sex categorization. In contrast, the sex of both young and older adults was shown to influence age categorization. The functional implications of these findings are discussed in light of previous person perception research

    Investigating the Early Stages of Person Perception: The Asymmetry of Social Categorization by Sex vs. Age

    Get PDF
    The wealth of information provided by facial cues presents challenges to our understanding of these early stages of person perception. The current study aimed to uncover the dynamics of processing multiply categorizable faces, notably as a function of their gender and age. Using a modified four-choice version of a mouse-tracking paradigm (which assesses the relative dominance of two categorical dimensions), the relative influence that sex and age have on each other during categorization of infant, younger adult, and older adult faces was investigated. Results of these experiments demonstrate that when sex and age dimensions are simultaneously categorized, only for infant faces does age influence sex categorization. In contrast, the sex of both young and older adults was shown to influence age categorization. The functional implications of these findings are discussed in light of previous person perception research

    Dissociable Neural Substrates for Agentic versus Conceptual Representations of Self

    Get PDF
    Although humans generally experience a coherent sense of selfhood, we can nevertheless articulate different aspects of self. Recent research has demonstrated that one such aspect of self—conceptual knowledge of one's own personality traits—is subserved by ventromedial prefrontal cortex (vMPFC). Here, we examined whether an alternative aspect of “self”—being an agent who acts to achieve one's own goals—relies on cognitive processes that overlap with or diverge from conceptual operationalizations of selfhood. While undergoing fMRI, participants completed tasks of both conceptual self-reference, in which they judged their own or another person's personality traits, and agentic self-reference, in which they freely chose an object or watched passively as one was chosen. The agentic task failed to modulate vMPFC, despite producing the same memory enhancement frequently observed during conceptual self-referential processing (the “self-reference” effect). Instead, agentic self-reference was associated with activation of the intraparietal sulcus (IPS), a region previously implicated in planning and executing actions. Experiment 2 further demonstrated that IPS activity correlated with later memory performance for the agentic, but not conceptual, task. These results support views of the “self” as a collection of distinct mental operations distributed throughout the brain, rather than a unitary cognitive system

    Effect of angiotensin-converting enzyme inhibitor and angiotensin receptor blocker initiation on organ support-free days in patients hospitalized with COVID-19

    Get PDF
    IMPORTANCE Overactivation of the renin-angiotensin system (RAS) may contribute to poor clinical outcomes in patients with COVID-19. Objective To determine whether angiotensin-converting enzyme (ACE) inhibitor or angiotensin receptor blocker (ARB) initiation improves outcomes in patients hospitalized for COVID-19. DESIGN, SETTING, AND PARTICIPANTS In an ongoing, adaptive platform randomized clinical trial, 721 critically ill and 58 non–critically ill hospitalized adults were randomized to receive an RAS inhibitor or control between March 16, 2021, and February 25, 2022, at 69 sites in 7 countries (final follow-up on June 1, 2022). INTERVENTIONS Patients were randomized to receive open-label initiation of an ACE inhibitor (n = 257), ARB (n = 248), ARB in combination with DMX-200 (a chemokine receptor-2 inhibitor; n = 10), or no RAS inhibitor (control; n = 264) for up to 10 days. MAIN OUTCOMES AND MEASURES The primary outcome was organ support–free days, a composite of hospital survival and days alive without cardiovascular or respiratory organ support through 21 days. The primary analysis was a bayesian cumulative logistic model. Odds ratios (ORs) greater than 1 represent improved outcomes. RESULTS On February 25, 2022, enrollment was discontinued due to safety concerns. Among 679 critically ill patients with available primary outcome data, the median age was 56 years and 239 participants (35.2%) were women. Median (IQR) organ support–free days among critically ill patients was 10 (–1 to 16) in the ACE inhibitor group (n = 231), 8 (–1 to 17) in the ARB group (n = 217), and 12 (0 to 17) in the control group (n = 231) (median adjusted odds ratios of 0.77 [95% bayesian credible interval, 0.58-1.06] for improvement for ACE inhibitor and 0.76 [95% credible interval, 0.56-1.05] for ARB compared with control). The posterior probabilities that ACE inhibitors and ARBs worsened organ support–free days compared with control were 94.9% and 95.4%, respectively. Hospital survival occurred in 166 of 231 critically ill participants (71.9%) in the ACE inhibitor group, 152 of 217 (70.0%) in the ARB group, and 182 of 231 (78.8%) in the control group (posterior probabilities that ACE inhibitor and ARB worsened hospital survival compared with control were 95.3% and 98.1%, respectively). CONCLUSIONS AND RELEVANCE In this trial, among critically ill adults with COVID-19, initiation of an ACE inhibitor or ARB did not improve, and likely worsened, clinical outcomes. TRIAL REGISTRATION ClinicalTrials.gov Identifier: NCT0273570

    Intraparietal Sulcus Activity During Explicit Self-Referential Social Status Judgments about Others

    No full text
    Previous research has suggested that the intraparietal sulcus (IPS) supports judgments of social distance, with greater activity observed in response to targets judged to be closer to each other (Yamakawa, Kanai, Matsumura, & Naito, 2009). Amongst other stimuli, activity in the IPS appears to be responsive to targets varying in social status (Chiao et al., 2009; Cloutier, Ambady, Meagher, & Gabrieli, 2012). The current project examined brain responses during explicit self-referential social status judgments of targets varying in either financial or moral status. Using an event-related fMRI design, participants viewed photographs of male faces paired with distinct levels of financial or moral status. During the task, participants were asked to explicitly identify each target’s status in relation to their own. Focusing on IPS activity, results from whole-brain and region of interest analyses revealed an interaction between social status types and levels. The implications of these results are discussed with respect to our current understanding of the impact of social status on the neural substrates of person perception.Investigación previa ha sugerido que el surco intraparietal (IPS) respalda juicios de distancia social, con mayor actividad observada en respuesta a objetivos juzgados para estar más cerca de otros (Yamakawa, Kanai, Matsumura, & Naito, 2009). Entre otros estímulos, la actividad en el surco intraparietal parece ser receptiva a objetivos variando en estatus sociales (Chiao et al., 2009; Cloutier, Ambady, Meagher, & Gabrieli, 2012). El presente proyecto examinó las respuestas cerebrales durante juicios de estatus sociales auto-referenciales de objetivos variando tanto en estatus morales como financieros. Usando un diseño de resonancia magnética asociada a evento, los participantes observaron fotografías de rostros masculinos emparejadas con distintos niveles de estatus financieros o morales. Durante la tarea, se les pidió a los participantes identificar explícitamente el estatus de cada objetivo en relación al de ellos. Enfocándose en la actividad del surco intraparietal, los resultados de los análisis del cerebro entero y de regiones de interés revelaron una interacción entre los tipos y niveles de estatus sociales. Las implicaciones de estos resultados son discutidas con respecto a nuestro entendimiento actual del impacto del estatus social en los substratos neuronales de la percepción de las personas

    Actividad del Surco Intraparietal Durante Juicios de Estatus Sociales Auto-Referenciales De Otros

    No full text
    Previous research has suggested that the intraparietal sulcus (IPS) supports judgments of social distance, with greater activity observed in response to targets judged to be closer to each other (Yamakawa, Kanai, Matsumura, & Naito, 2009). Amongst other stimuli, activity in the IPS appears to be responsive to targets varying in social status (Chiao et al., 2009; Cloutier, Ambady, Meagher, & Gabrieli, 2012). The current project examined brain responses during explicit self-referential social status judgments of targets varying in either financial or moral status. Using an event-related fMRI design, participants viewed photographs of male faces paired with distinct levels of financial or moral status. During the task, participants were asked to explicitly identify each target’s status in relation to their own. Focusing on IPS activity, results from whole-brain and region of interest analyses revealed an interaction between social status types and levels. The implications of these results are discussed with respect to our current understanding of the impact of social status on the neural substrates of person perception.Investigación previa ha sugerido que el surco intraparietal (IPS) respalda juicios de distancia social, con mayor actividad observada en respuesta a objetivos juzgados para estar más cerca de otros (Yamakawa, Kanai, Matsumura, & Naito, 2009). Entre otros estímulos, la actividad en el surco intraparietal parece ser receptiva a objetivos variando en estatus sociales (Chiao et al., 2009; Cloutier, Ambady, Meagher, & Gabrieli, 2012). El presente proyecto examinó las respuestas cerebrales durante juicios de estatus sociales auto-referenciales de objetivos variando tanto en estatus morales como financieros. Usando un diseño de resonancia magnética asociada a evento, los participantes observaron fotografías de rostros masculinos emparejadas con distintos niveles de estatus financieros o morales. Durante la tarea, se les pidió a los participantes identificar explícitamente el estatus de cada objetivo en relación al de ellos. Enfocándose en la actividad del surco intraparietal, los resultados de los análisis del cerebro entero y de regiones de interés revelaron una interacción entre los tipos y niveles de estatus sociales. Las implicaciones de estos resultados son discutidas con respecto a nuestro entendimiento actual del impacto del estatus social en los substratos neuronales de la percepción de las personas
    corecore