从对立走向统一——生态伦理学发展趋势研究

在生态伦理学研究中,人类中心主义和非人类中心主义围绕自然存在物有无道德地位等问题展开了激烈争论。这种争论的不可调和性及其观点的不可公度性,意味着生态伦理学自身发生了严重的形而上学危机。如何摆脱这一危机,使生态伦理学研究向纵深发展,成为摆在人们面前的一项重要任务。黑格尔关于人的自由意志是一个否定之否定过程的观点为走出这种争论提供了理论依据,马克思关于人与自然界完成本质统一的思想亦为消解这种对立奠定了理论基础。     

The “Brightening” Effect: Reactions to Positive Events in the Daily Lives of Individuals With Major Depressive Disorder and Generalized Anxiety Disorder

Depressed individuals are less reactive than healthy individuals to positive stimuli in the laboratory, but accumulating evidence suggests that they are more emotionally reactive to positive events in their daily lives. The present study probed the boundaries of this curious “mood brightening” effect and investigated its specificity to major depressive disorder (MDD) vis-à-vis generalized anxiety disorder (GAD), its closest boundary condition. We used ecological momentary assessment to measure reactions to positive events over one week in individuals with MDD (n = 38), GAD (n = 36), comorbid MDD-GAD (n = 38), and no psychopathology (n = 33). Depressed individuals responded to positive events with larger changes in affect, cognition, reported withdrawal (but not approach) behavior, and symptoms than healthy controls. More severe depression assessed before the sampling week predicted greater brightening. Altered reactivity to positive events was relatively specific to MDD when compared with GAD, similar to patterns found for other positive emotional processes. The robustness, scope, and relative specificity of the brightening effect highlights the need to resolve conflicting findings across laboratory and non-laboratory studies to advance understanding of altered reactivity in emotional disorders.     

Anxiety Influences the Perceptual-Motor Calibration of Visually Guided Braking to Avoid Collisions

We investigated whether anxiety influences perceptual-motor calibration in a braking to avoid a collision task. Participants performed either a discrete braking task (Experiment 1) or a continuous braking task (Experiment 2), with the goal of stopping before colliding with a stop sign. Half of participants performed the braking task after an anxiety induction. We investigated whether anxiety reduced the frequency of crashing and if it influenced the calibration of perception (visual information) and action (brake pressure) dynamically between-trials in Experiment 1 and within-trials in Experiment 2. In the discrete braking task, anxious participants crashed less often and made larger corrective adjustments trial-to-trial after crashing, suggesting that the influence of anxiety on behavior did not occur uniformly, but rather dynamically with anxiety amplifying the reaction to previous crashes. However, when performing continuous braking, anxious participants crashed more often, and their within-trial adjustments of deceleration were less related to visual information compared to controls. Taken together, these findings suggest that the timescale and nature of the task mediates the influence of anxiety on the performance of goal-directed actions.     

Effects of different attention tasks on concurrent speech in adults who stutter and fluent controls

Purpose: Motor theories indicate that focusing attention on well-practiced movements interferes with skilled performance; however, specific forms of attention (alerting vs. orienting vs. executive control) associated with this effect are not well understood. The present study explored this question in relation to stuttering, and examined whether dual task conditions that engaged sustained attention or working memory (WM) affected speech fluency in different ways. We also considered whether fluency changes were associated with changes in speech rate and language.Methods: Nineteen adults who stutter (AWS) and 20 controls produced spontaneous speech under a baseline condition and two dual task conditions: one involving a sustained attention task, the other involving WM demands.Results: Both groups produced fewer stutter-like disfluencies under dual task relative to baseline conditions and this reduction did not differ between the two dual tasks (attention vs. WM). Speech rate and language variables, which were potentially influenced by attention conditions, were not affected by dual tasks in the same way as disfluencies, and appeared to be unassociated with fluency results.Conclusions: Findings indicate that atypical disfluencies decrease when attention is divided, even when secondary task demands are minimal, as they were in the sustained attention task. For simple secondary tasks, fluency changes do not appear to be a byproduct of slowed rate and are not accompanied by observable changes in language. These results demonstrate that simple manipulations of attention can induce measurable effects on aspects of speech production, and may be a useful tool for facilitating fluency in clinical intervention.     

Repetition of a cognitive task promotes motor learning

Motor learning plays an important role in the acquisition of new motor skills. In this study, we investigated whether repetition of a cognitive task promoted motor learning. Fifty-one young adults were assigned to either the early, late, or control groups. All participants completed a mouse tracking task in which they manipulated a mouse to track a moving target on a screen. The cursor was rotated 165° in the counterclockwise direction from the actual mouse position, requiring participants to learn how to use a new tool. To determine the task performance, we calculated the distance between the cursor and target position. In addition, to assess the effects of a cognitive task on the progress of motor learning, curve fitting of the learning curves was performed for the total distance. Experiments were conducted as per the following schedule: learning day 1 (L1), learning day 2 (L2: the day after learning day 1), retention day 1 (R1: 2 weeks after learning day 1), and retention day 2 (R2: 4 weeks after learning day 1). Participants underwent mouse tracking for 20 min on L1 and L2 and for 3 min on R1 and R2. As a cognitive task, we adopted the N-back task. The early or late group performed the N-back task for 20 min before performing motor tracking task on L1 or L2, respectively. The control group did not perform the N-back task. Based on curve fitting analysis, it was observed that the rate of change for motor learning in the early group was higher than that in the control group. The retention of motor learning did not differ between all groups. Our results indicate that the repetition of a cognitive task enhanced in the early phase of motor learning of the mouse tracking task.     

Dissociative effects of normative feedback on motor automaticity and motor accuracy in learning an arm movement sequence

Within a pre-post-design, we scrutinized the effects of normative augmented feedback with positive and negative valence on learning motor accuracy, consistency as well as automaticity by means of a dual-task paradigm. Forty-two healthy physical education students were instructed to produce an arm-movement sequence as precisely as possible with regard to three spatial reversal points within a time limit of 1200 ms. Twenty-eight practiced an elbow-extension-flexion-sequence (690 trials) and 14 participants were tested as a control group without feedback practice. Valence of normative feedback was systematically manipulated by means of reference lines in a visual feedback display. The reference lines indicated performance of a putative peer-group either to be superior (negative valence, Normative-Negative-Group) or inferior (positive valence, Normative-Positive-Group) to participants’ actual performance.As a result, dual-task costs (n-back error) significantly decreased solely in the Normative-Positive-Group, p = .003, η²_p = .51, but in no other group. Surprisingly, the mean absolute error for the motor task significantly decreased (i.e., precision increased) only in the Normative-Negative-Group with a large effect size, but in none of the other groups. Motor consistency was not significantly affected by the valence of normative feedback. According to the hypotheses of error-provoked attentional control, positive feedback-valence appears to enhance skill automatization, while – unexpectedly – only negative feedback-valence seems to enhance movement precision, which may be explained by effects of feedback valence on the learners aspiration level.     

Too good to be true? Psychological responses to uncommon options in risk–reward environments

Risks and rewards, or payoffs and probabilities, are inversely related in many choice environments. We investigated people's psychological responses to uncommon combinations of risk and reward that deviate from learned regularities (e.g., options that offer a high payoff with an unusually high probability) as they evaluated risky options. In two experiments (N = 183), participants first priced monetary gambles drawn from environments in which risks and rewards were negatively correlated, positively correlated, or uncorrelated. In later trials, they evaluated gambles with uncommon combinations of risk and reward—that is, options that deviated from the respective environment's risk–reward structure. Pricing, response times, and (in Experiment 2) pupil dilation were recorded. In both experiments, participants took more time when responding to uncommon compared to foreseeable options or when the same options were presented in an uncorrelated risk–reward environment. This result was most pronounced when the uncommon gambles offered higher expected values compared to the other gambles in the set. Moreover, these uncommon, high‐value options were associated with an increase in pupil size. These results suggest that people's evaluations of risky options are based not only on the options' payoffs and probabilities but also on the extent to which they fit the risk–reward structure of the environment.     

Concordance of teacher-rated and performance-based measures of executive functioning in preschoolers

The most common method used to evaluate child behavior and functioning is rating scales completed by parents and/or teachers. Given that executive functioning (EF) plays a fundamental role in the developing child’s cognitive, behavioral, and social-emotional development, it would be ideal if ratings of EF and performance-based EF measures assess the same construct. However, most studies report a small to negligible association between performance-based measures and ratings of EF. There are few studies investigating this association for preschoolers, and most only include parent ratings. Teachers may be more reliable reporters of EF behaviors due to the higher demand for EF skills in the preschool setting than at home and because teachers may have a better sense of what behaviors are normative. In this study, we reviewed the associations between three EF rating scales completed by teachers on 243 preschool children. Results showed small to moderate correlations with EF measures of inhibition and cognitive flexibility/switching for all three scales, with the strongest associations observed between Child Behavior Rating Scale (CBRS) Behavioral Regulation subscale and child EF measures. Exploratory multivariate path analyses showed that, after controlling for age, sex, and socioeconomic status (SES), Behavioral Regulation significantly predicted performance-based measures of EF and accounted for incrementally more variance in the models. We conclude that in ideal situations, it is best to measure EF using both rating scales and performance-based measures of EF. The CBRS seems to be a sensitive measure of EF in preschoolers and may be a helpful brief screening tool for use with teachers.     

Action co-representation and the sense of agency during a joint Simon task: Comparing human and machine co-agents

Recent studies have suggested that individuals are not able to develop a sense of joint agency during joint actions with artificial systems. We sought to examine whether this lack of joint agency is linked to individuals’ inability to co-represent the machine-generated actions. Fifteen participants observed or performed a Simon response time task either individually, or jointly with another human or a computer. Participants reported the time interval between their response (or the co-actor response) and a subsequent auditory stimulus, which served as an implicit measure of participants’ sense of agency. Participants’ reaction times showed a classical Simon effect when they were partnered with another human, but not when they collaborated with a computer. Furthermore, participants showed a vicarious sense of agency when co-acting with another human agent but not with a computer. This absence of vicarious sense of agency during human-computer interactions and the relation with action co-representation are discussed.