The traditional achromatic Mach card effect is an example of lightness inconstancy and a demonstration of how shape and lightness perception interact. We present a quantitative study of this phenomenon and explore the conditions under which it occurs. The results demonstrate that observers show lightness constancy only when sufficient information is available about the light-source position, and the perceptual task required of them is surface identification rather than direct colour-appearance matching. An analysis and comparison of these results with the chromatic Mach card effect (Bloj et al 1999 Nature 402 877-879) demonstrate that the luminance effects of mutual illumination do not account for the change in lightness perception in the traditional Mach card. 相似文献
The influence of stress on cardiac electrical stability (CES) and chaotic dynamics of the electrical activity of the heart was studied in acute and chronic experiments in rabbits. Stress was caused by 2-3 h daily immobilization of the animals with electrical stimulation of emotiogenic centers of the hypothalamus through implanted electrodes. CES was estimated by the thresholds for ventricular arrhythmia: paroxysmal ventricular tachycardia, repeated ventricular extrasystoles and ventricular fibrillation (VF). The results showed: (i) CES in stressed rabbits was decreased significantly compared with controls; (ii) the level of chaos at the onset of VF in stressed rabbits was increased significantly compared with controls; (iii) heart rate of stressed rabbits was significantly greater than in controls; (iv) changes in CES parameters depended on whether stress was acute or chronic; (v) acute stress promoted transition of spontaneously reversible VF into spontaneously irreversible VF. Thus, stress increased the degree of disorganization of heart electrical activity and also decreased its electrical stability. The experiments indicate that stress is a destabilizing factor influencing the reversibility of heart rate disorders. The probability of such reversibility depends on whether stress is acute or chronic: acute stress is more likely to lead to irreversible spontaneous VF. 相似文献
We addressed the issue of how display orientation affects the perception of biological motion. In Experiment 1, spontaneous recognition of a point-light walker improved abruptly with image-plane display rotation from inverted to upright orientation. Within a range of orientations from 180 degrees to 90 degrees, it was dramatically impeded. Using ROC analysis, we showed (Experiments 2 and 3) that despite prior familiarization with a point-light figure at all orientations, its detectability within a mask decreased with a change in orientation from upright to a range of 90 degrees-180 degrees. In Experiment 4, a priming effect in biological motion was observed only if a prime corresponded to a range of deviations from upright orientation within which the display was spontaneously recognizable. The findings indicate that display orientation nonmonotonically affects the perception of biological motion. Moreover, top-down influence on the perception of biological motion is limited by display orientation. 相似文献
The map is a small-scaled version of the space it represents. It has been argued that children have difficulty interpreting maps because they do not understand scale relations. Recent research has shown that even preschoolers can solve problems that involve scaling in one dimension. This study examined whether early scaling ability extends to tasks involving two-dimensional maps and referent spaces of different sizes. Results showed that about 60% of the 4-year-olds and 90% of the 5-year-olds tested used distance information presented on a map to locate an object in a two-dimensional spatial layout. Children had more difficulties in solving mapping tasks with a larger referent space. This decrease in accuracy as a function of space size on the mapping task was greater than would have been expected on the basis of performance on a parallel nonmapping task. The results are discussed in terms of their implications for the mechanisms underlying early scaling ability. 相似文献
Our research examines the effect of subjective financial vulnerability on prosocial activity. First, data from the European Survey of Health, Aging and Retirement (SHARE) revealed that higher assessment of one's financial vulnerability might be associated with prosocial motivation for social activities. Next, we manipulated participants' perception of their relative financial position compared to their peers and found that participants randomly assigned to the low financial position condition were more willing to volunteer than participants assigned to the high financial position condition. In Study 3, we manipulated participants' financial advantage. Participants who were disadvantaged in the experimental settings were more willing to volunteer and donate to charity compared to participants with financial advantage. In our final study, we examined willingness to donate to in‐group and out‐group help organizations and found that individuals of lower perceived financial standing may be motivated by the goal of increasing the strength of the social group, rather than by expectations of direct reciprocity. We also found that emotional distress mediates the relationship between perceived financial vulnerability and prosocial behavior. In line with earlier research illustrating that lower financial status promotes prosociality on an interpersonal level, we demonstrate that even momentary perception of relative financial disadvantage and vulnerability promotes prosociality in the broader social context. 相似文献
Emotional Lability (EL) is a source of impairment in multiple mental disorders of children, including attention-deficit/hyperactivity disorder (ADHD). It has been proposed that the overlap between EL and ADHD symptoms is the result of common neuropsychological deficits. The aim of the present study was to test this hypothesis by using a multi-method approach. In a mixed sample of 61 children (49 community sample and 12 children with an ADHD diagnosis) aged between 8 and 12 years, we examined the relationship between parental reports of ADHD and EL, real-time children’s emotional expressions in an experimental context, children’s performance on neuropsychological tasks and parental ratings of neuropsychological functioning. Parental EL ratings were significantly predicted by task-based reaction time variability and by questionnaire measures of Self-Direction & Organization and Arousal Regulation. Parental EL ratings were also significantly related to both ADHD symptom dimensions. After controlling for shared neuropsychological factors, ADHD symptoms no longer predicted parental EL ratings. Neuropsychological task performance was not significantly related to real time emotional expressions. However, positive emotional expressions were significantly predicted by higher parental ratings of Cognition and negative emotional expressions by parental ratings of low Effort engagement – accounting for some of the correlation with ADHD symptoms. The current results highlight the plausible role of cognitive energetic processes in explaining the EL and ADHD symptom association.
Social Psychology of Education - The aim of the study was to enhance understanding of how seventh graders vary in emotional engagement and experienced well-being at school in terms of anxiety and... 相似文献
Animal Cognition - Distress calls are an acoustically variable group of vocalizations ubiquitous in mammals and other animals. Their presumed function is to recruit help, but there has been much... 相似文献
Background: Previous studies suggested that affective state could enhance stimulus salience and modulate attention allocation for mood-congruent information, but contrasting data have been reported on the effects of mood induction on attentional biases for threat (ABTs) in non-clinical individuals.
Objective: We aimed to assess whether laboratory-induced negative mood can increase individuals’ tendency to allocate attention on threatening stimuli, thus determining a difficulty in attentional disengagement from threat. We also aimed at assessing whether level of trait anxiety could modulate the effect of mood induction on attentional biases.
Methods: We used an autobiographical episode recall procedure for mood induction (fear, happiness and neutral episode recall), and an exogenous cueing task with threatening and non-threatening images to assess attentional biases in 120 undergraduate students.
Results: Participants showed a significant difficulty in disengaging attention from threat after recalling fear-related episodes, independently from their trait anxiety level.
Conclusions: These findings clarify that the ABTs are not exclusive to anxiety disorders or high trait anxiety individuals, and could also arise in non-clinical individuals in a fearful context. 相似文献
Youth involved in the juvenile justice system are at risk for emotional and behavioral problems. However, research with court-involved adolescents has neglected to examine the mental health of their parents, who may also have significant personal and parenting stress. This sample consisted of 144 parent–adolescent dyads. Adolescents (aged 11–17 years) identified by court officials were referred to the study to receive mental health treatment. Parents and adolescents completed surveys about their mental health diagnoses, treatment, and family relationships. Using the clinical cut-off for the global severity index of the Symptom Checklist-90-Revised, bivariate and multiple logistic regression analyses were performed to examine group differences between parents with and without significant mental health symptoms. Results indicated that 35% of parents endorsed clinically significant mental health symptoms. Parents with clinically significant symptoms, compared to those without, reported significantly greater parenting stress (p?<?.05), and were more likely to have received prior mental health treatment (54 vs. 25%; p?<?.05) and a psychiatric diagnosis (52 vs. 19%; p?<?.05). Our findings revealed that more than one in three parents of court-involved adolescents are currently experiencing significant mental health symptoms. Improved mental health screening and intervention that incorporates the unique needs of families is recommended, including the possible use of family-based approaches as well as individualized treatment for the parents of court-involved youth. 相似文献