Oral self-administration of pentobarbital by rhesus monkeys: maintenance of behavior by different concurrently available volumes of drug solution.

For 4 rhesus monkeys, mouth-contact responses with either of two brass spouts were reinforced according to fixed-ratio schedules by 0.65-mL liquid deliveries during daily 3-hr sessions. Three experiments were conducted. In each experiment, independent fixed-ratio schedules were concurrently in effect at the two spouts. Following completion of each fixed ratio on a spout, a specified number of liquid deliveries were available from that spout under a continuous-reinforcement schedule. The number of such deliveries available at each spout was manipulated independently. In Experiment 1, a 1-mg/mL pentobarbital solution was simultaneously available with water (the drug vehicle) under concurrent fixed-ratio schedules of 32 responses for 3 subjects and 64 responses for the remaining subject. The number (N) of liquid deliveries that were available after completion of each fixed ratio was varied in the following order: 8, 4, 2, 1, and 8 (retest). For each subject at each condition, drug maintained more responding than water. The number of drug deliveries obtained per session was directly related to the amount of drug available per fixed ratio (i.e., to N), whereas the number of fixed ratios completed per session generally was inversely related to the value of N. In Experiment 2, fixed-ratio size was the same for each subject as in Experiment 1, but deliveries of a 1-mg/mL pentobarbital solution were available at both spouts. The number of drug deliveries available under one fixed-ratio schedule (Ns, the "standard" reinforcer amount) was held at eight, and the number of drug deliveries available under the second schedule (Nc, the "comparison" reinforcer amount) was changed across blocks of six sessions of stable responding in the following order: 1, 2, 4, 8, 4, 2, and 1. The identical series of comparison reinforcer amounts (Nc) was then tested twice more, but with the standard reinforcer (Ns) held first at four and then at two deliveries. Across the three choice series, reinforcing effects were directly related to reinforcer magnitude. In Experiment 3, deliveries of a 1-mg/mL pentobarbital solution again were available at both spouts. However, the two reinforcer amounts were held constant at N = 8 deliveries under one schedule and N = 4 deliveries under the second schedule, and fixed-ratio size was systematically varied. Across the range of fixed-ratio sizes from low to high, the degree to which behavior was better maintained by the larger of the two drug quantities was an inverted U-shaped function of fixed-ratio size.(ABSTRACT TRUNCATED AT 400 WORDS)     

Effect of observing response requirements to sample and comparison stimuli on the establishment of reject control (sample/S- relations)

The establishment of sample/S- relations (or reject control) during conditional discrimination training (AB, BC) affects transitivity (AC), equivalence (CA) and reflexivity (AA, BB, CC) test outcomes. The present study parametrically evaluated the effects of different observing patterns to comparison stimuli on the establishment of reject control during baseline conditional relation training. A matching-to-sample with observing requirements (MTS-OR) procedure was implemented during AB and BC conditional discrimination training. During training, the participants were required to observe the sample and incorrect comparison on every trial before responding. In addition, the participants were divided into three groups that differed regarding the percentage of training trials on which they were prevented from observing the correct comparison stimuli: 25%, 50%, and 75%. Once the mastery criteria were achieved during training, transitivity (AC), symmetry (BA, CB), equivalence (CA), and reflexivity (AA, BB, CC) tests were conducted with all comparison stimuli visible from the beginning. The results suggest that the number of errors during transitivity, equivalence, and reflexivity tests progressively increased as participants were prevented from observing the correct comparison on a greater number of trials during training. Symmetry test results, however, were not affected by the experimental manipulation. Moreover, the number of participants showing reject-control patterns during tests slightly increased and the number of participants showing select-control patterns decreased as a function of the number of trials on which the participants were prevented from observing the correct comparison. Thus, we suggest that observing patterns during training is a relevant variable that affects equivalence test outcomes.     

Anxiety after remembering stressful academic versus brush with death events: The moderating roles of future time perspective and personal intimacy

This study examines: (i) whether recalling stressful autobiographical events results in anxiety, (ii) the relation of memory qualities to anxiety, and (iii) the relation of future time perspective and personal intimacy to experiencing anxiety. Participants (N = 120) completed Future Time Perspective, Personal Intimacy and State Anxiety scales. They were randomly assigned to recall a brush with death, a stressful academic deadline, or a no-stress control. Memory qualities (vividness and significance) were assessed. As expected, recalling stressful events resulted in anxiety with more personally significant events related to higher anxiety. Having a more open-ended future time perspective related to lower anxiety after recalling a stressful academic deadline, whereas greater personal intimacy predicted lower anxiety after recalling a brush with death. Findings are discussed in terms of factors that may serve to moderate the link between stressful memories and the experience of anxiety.     

Social Facilitation as a Function of the Mere Presence of Others

Abstract

According to R. B. Zajonc's (1965) drive theory of social facilitation, the mere presence of others increases arousal and, thereby, the frequency of dominant responses (i.e., responses with the greatest habit strength). In the present experiment, U.S. undergraduates performed a stimulus discrimination task under 1 of 2 conditions: in the presence of another individual (audience) or alone. The mere presence condition was designed to make it difficult for the participants to attend directly to the audience. The task was designed to minimize the likelihood that the specific response (numerical preference) would be attributable to a desire to respond appropriately to the audience. There was a significant difference in the mean number of dominant responses between the participants in the audience condition and those in the alone condition. The results provide support for Zajonc's mere presence drive theory of social facilitation.     

Dual-tasking alleviated sleep deprivation disruption in visuomotor tracking: an fMRI study

Effects of dual-responding on tracking performance after 49-h of sleep deprivation (SD) were evaluated behaviorally and with functional magnetic resonance imaging (fMRI). Continuous visuomotor tracking was performed simultaneously with an intermittent color-matching visual detection task in which a pair of color-matched stimuli constituted a target and non-matches were non-targets. Tracking error means were binned time-locked to stimulus onset of the detection task in order to observe changes associated with dual-responding by comparing the error during targets and non-targets. Similar comparison was made with fMRI data. Our result showed that despite a significant increase in the overall tracking error post SD, from 20 pixels pre SD to 45 pixels post SD, error decreased to a minimum of about 25 pixels 0-6s after dual-response. Despite an overall reduced activation post SD, greater activation difference between targets and non-targets was found post SD in task-related regions, such as the left cerebellum, the left somatosensory cortex, the left extrastriate cortex, bilateral precuneus, the left middle frontal gyrus, and the left motor cortex. Our results suggest that dual-response helps to alleviate performance impairment usually associated with SD. The duration of the alleviation effect was on the order of seconds after dual-responding.     

Stressful Events and Temperament Change during Early and Middle Adolescence: The TRAILS Study

This project investigates how stressful events are related to deviations from normative temperament development during adolescence. Temperament traits were assessed at ages 11 and 16 years. Life‐event data was captured using an interview (total n = 1197). Normative changes were found in all traits. A linear trend was found between the experience of stressful events and temperament development. Adolescents exposed to stressful events showed smaller decreases in fear and shyness, stronger decreases in effortful control and affiliation and smaller increases in high intensity pleasure. Exposure to stressful events was related to increases in frustration instead of decreases. Our results show that whereas normative development is mostly in the direction of maturation, adolescents who experienced stressful events showed less maturation of their temperament. Copyright © 2011 John Wiley & Sons, Ltd.     

The influence of sexual harassment frequency and perceptions of organizational justice on victim responses to sexual harassment

Organizational justice theory was used to understand the conditions that influence how women respond when sexually harassed. Specifically, this study examined whether sexual harassment frequency interacts with perceptions of four types of organizational justice (procedural, distributive, interpersonal, and informational) to predict two types of victim responses (confrontation and reporting). With data collected from 257 female employees, it was found that the interaction between sexual harassment frequency and perceptions of distributive justice and the interaction between sexual harassment frequency and perceptions of procedural justice predicted reporting, whereas the interaction between sexual frequency and perceptions of distributive justice predicted confrontation. The interaction between sexual harassment frequency and perceptions of informational justice predicted both confrontation and reporting. Implications for organizations are discussed.     

Effects of saccades and response type on the Simon effect: If you look at the stimulus,the Simon effect may be gone

The Simon effect has most often been investigated with key-press responses and eye fixation. In the present study, we asked how the type of eye movement and the type of manual response affect response selection in a Simon task. We investigated three eye movement instructions (spontaneous, saccade, and fixation) while participants performed goal-directed (i.e., reaching) or symbolic (i.e., finger-lift) responses. Initially, no oculomotor constraints were imposed, and a Simon effect was present for both response types. Next, eye movements were constrained. Participants had to either make a saccade toward the stimulus or maintain gaze fixed in the screen centre. While a congruency effect was always observed in reaching responses, it disappeared in finger-lift responses. We suggest that the redirection of saccades from the stimulus to the correct response location in noncorresponding trials contributes to the Simon effect. Because of eye–hand coupling, this occurred in a mandatory manner with reaching responses but not with finger-lift responses. Thus, the Simon effect with key-presses disappears when participants do what they typically do—look at the stimulus.     

Polarization or bridging? Responses of Muslim and non-Muslim organizations to criticism of Islam in the Netherlands

Since the beginning of the twenty-first century, Islam has been a target of harsh criticism in the Netherlands, as in many other European countries. This article examines and analyses the way leaders of 10 Muslim and 11 non-Muslim organizations responded to criticism of Islam in the Netherlands in the period 2004–10. The focus is on the response to five episodes: the film Submission (2004), the Danish Cartoon Affair (2005–2006), the film Fitna (2008), the Internet film An interview with Mohammed (2008) and the Swiss ban on the building of minarets (2009). Several specific patterns of response are noted. The responses of Muslim organizations vary from resignation to defensive to offensive, and those of non-Muslim organizations from supportive to critical. These patterns are strongly linked to the organizations' leaders' framing of the situation, including the incidents themselves and other organizations, and their own mission and strategy, as well as, in the case of Fitna, to the policy of the Dutch government. All the organizations researched reject extreme forms of polarization and the mainstream Christian, Islamic and Jewish organizations in particular have strengthened their mutual ties in response to expressions of criticism of Islam.     

感恩对青少年学业成就的影响：有调节的中介效应

本研究提出一个有调节的中介模型,揭示了感恩“怎样”影响学业成就及这种影响“何时”更强或更弱。采用感恩问卷、日常性学业复原力问卷、压力性生活事件量表和学业成就问卷对1361名青少年进行调查。结果显示:(1)日常性学业复原力对感恩与学业成就的关系具有部分中介效应,感恩既对学业成就产生直接影响,也通过日常性学业复原力对学业成就产生间接影响;(2)压力性生活事件对日常性学业复原力的中介作用具有调节效应,压力性生活事件调节了中介过程的后半路径,具体而言,日常性学业复原力对学业成就的影响,随压力性生活事件的增加而降低。因此,感恩对青少年学业成就的影响是有调节的中介效应。研究结论对提高青少年的学业成就具有重要的理论价值和参考价值。