Prediction and control as determinants of behavioural uncertainty: effects on task performance and heart rate reactivity.

Control or control-belief is often viewed as being directly instrumental in facilitating coping mechanisms in aversive situations, and yet the empirical evidence for the beneficial effects of control is inconclusive. In this study we investigated the role of predictability in determining the effects of perceived control during an aversive reaction time task. Fifty-six subjects were allocated to one of four groups; predictable-control, predictable-no control, unpredictable-control, unpredictable-no control. In the predictable conditions, subjects could temporally predict the occurrence of an aversive noise. In the perceived control conditions, duration of the aversive tone was contingent on subject's performance. All subjects were matched in terms of the nature of the task and in the number and time of receipt of both the warning signal and noise. Heart rate reactivity and two performance parameters were measured, reaction time and performance increase. Both predictability and control-belief led to a reduction in heart rate reactivity, although they appeared to function independently and at different points in the sequence of events. That is, predictability or perceived control was sufficient to mitigate the effects of an aversive situation. Neither perception of control or predictability led to better task performance. These results are discussed in terms of behavioural uncertainty explanations.     

Perceived control in continuous loud noise

The effects of two types of perceived control were assessed for performance during and following exposure to continuous loud noise at 90 dBC. Subjects performed a tracking task during exposure and the Stroop test in the period following exposure. Control could be effected either (1) by attenuating the intensity of the noise or (2) by reducing the difficulty of the tracking task. In both cases subjects were encouraged not to exercise control. Performance in treatments involving loud (90 dBC) and soft (55 dBC) noise served as baseline conditions. Perceived control of task difficulty accentuated the tendency for root-mean-square error to rise during the tracking task. There were no significant effects of noise intensi ty on tracking performance. Loud noise reduced the incidence of errors in the Stroop test but perceived control failed to influence this effect. The results are discussed in terms of the generality of perceived control phenomena.     

Duration of failure,causal attributions for failure,and subsequent reactions

Subjects were given a preliminary problem solving task of either short or long duration, and were told that they could shorten the duration of aversive noise bursts by correctly solving the problems. They were then given false feedback that they had done either well or poorly on the problems. Two groups of failing subjects were given information designed to lead them to attribute failure to either lack of ability or a difficult task. Two additional groups received “success” or “failure” feedback without any attributional cues. Failure-induced stress was reported to be greater under short duration conditions than under long duration conditions, and increased to the extent that subjects were led to believe they were personally responsible for failure. Following the preliminary failure period, task performance in the same situation and task performance and persistence in a different situation were assessed. In each case, performance and persistence decreased (a) following short-duration failure when subjects were led to attribute failure to a difficult task, and (b) following long-duration failure when subjects were led to attribute failure to lack of ability. These results are discussed within a framework that emphasizes the role of casual attributions in mediating the effects of failure.     

Locus of control and the effects of success and failure in young and community-residing aged women1

A study was conducted to examine reactions to success and failure in young and elderly subjects. Young and aged women, previously classified as internals or externals according to scores on a version of Rotter's (1966) Locus of Control Scale, were asked to work on cognitive problems while listening to bursts of noise. Two experimental conditions were created. One group (perceived success) was led to believe they were successfully avoiding bursts of noise by correctly solving the problems. A second group (perceived failure) believed they were unsuccessful at the problems and not avoiding noises. To test the generality of the effects of the treatments, subsequent performance was assessed on first, a similar task administered by the original experimenter, and secondly, on a dissimilar task given by a different experimenter in another setting. Results on a similar task indicated that subjects showed poor performance following failure regardless of age or locus of control classification. However, internals performed better than externals after both success and failure treatments. Testing the generality of these effects with a dissimilar task, results indicated that externals tended to perform somewhat more poorly after failure and internals somewhat better after failure. However, these I-E differences in reactions to success and failure were largely due to the elderly group, and old-externals showed the poorest performance after failure. The results were interpreted in terms of the particular importance of locus of control as a determinant of adaptability to stress in the elderly.     

The effect of control and predictability in learned helplessness

The present 2 x 2 study deals with the influence of controllability and predictability of an aversive noise stimulus on a subsequent learning task. Eighty-four subjects participated in two experiments. In correspondence with the concept of learned helplessness, controllability was shown to be the dominant factor in the first experiment. In the second experiment, a modified test task was used in which both factors were shown to act in specific ways: The main influence of controllability is upon response measures (latency, omission), whereas unpredictability retardates learning of new predictive connections. The results are discussed in terms of contingency learning.     

Attributions of causality and reactions to uncontrollable outcomes

The experiment tested the hypothesis that the stress experienced by a person who is unable to control aversive stimulation is not a function of lack of control per se, but of the attribution of causality that (s)he makes for failure to exert control. Subjects were given a problem-solving task, and were told that they could prevent aversive noise bursts by correctly solving the problems. Subjects then received false feedback that they had done either well or poorly on the problems. In addition, failing subjects received information that led them to attribute their performance either to their own lack of ability or to situational factors (task difficulty). Subjects who attributed their failure to their own incompetence felt considerably more stress than subjects who made situational attributions. In fact, the latter subjects experienced no more stress than subjects who were successful in controlling the stimulation. Surprisingly, subjects whose attributions for performance led them to feel personally incompetent performed better than the remaining subjects both on problems administered in the same situation, and on problems administered in a new and different situation. The implications of the results for future helplessness studies and for the learned helplessness model were discussed.     

Presence of human friends and pet dogs as moderators of autonomic responses to stress in women

Autonomic responses were measured while 45 adult women performed a standard experimental stress task in the laboratory with only the experimenter present and 2 weeks later at home in the presence of a female friend, pet dog, or neither. Results demonstrated that autonomic reactivity was moderated by the presence of a companion, the nature of whom was critical to the size and direction of the effect. Ss in the friend condition exhibited higher physiological reactivity and poorer performance than subjects in the control and pet conditions. Ss in the pet condition showed less physiological reactivity during stressful tasks than Ss in the other conditions. The results are interpreted in terms of the degree to which friends and pets are perceived as evaluative during stressful task performance. Physiological reactivity was consistent across the laboratory and field settings.     

Effects of personal causation and perceived control on responses to an aversive environment: The more control,the better

A laboratory experiment was conducted to investigate the effects on reactions to aversive noise of three types of personal control: control over the initiation of noise, control over its termination, and combined control over both initiation and termination. On an attention-to-detail measure which occurred concurrently with noise stimulation, subjects' error rates decreased linearly as degree of control increased. Likewise, on a post-noise measure of task persistence, subjects' performance rates increased linearly across the three conditions as degree of control increased. Results were discussed in terms of Seligman's theory of learned helplessness and deCharms' theory of personal causation, and the motivational effects of personal control were emphasized.     

Environmental determinants of altruism: The effects of stimulus overload and perceived control on helping

In an experiment designed to measure the effects of stimulus overload on altruism, 60 female subjects were randomly assigned to three stimulus conditions of 20 subjects each: (1) overload, (2) overload with perceived control, and (3) no overload. Subjects performed simultaneous proofreading and number attention tasks while at the same time listening to distracting or nondistracting background sound, and one group believed they could have the sound turned off if they desired. Following task performance, all subjects received a request for a favor from an ostensibly unrelated confederate. Although all subjects performed the tasks about equally well regardless of stimulus condition, altruism increased significantly across the three conditions. Results were discussed in terms of stimulus overload associated with the urban environment.     

准备时间和预先信息对任务切换的影响

两个实验采用任务线索范式,考察了准备时间和预先信息对任务切换的影响。实验1的准备时间为可预测,实验2的为不可预测,以考察准备时间的可预测性对任务切换的影响。以被试执行重复任务、切到任务和切离任务的正确反应时为主要指标,结果：（1）在准备时间可预测和不可预测两种条件下,准备时间和预先信息之间存在显著交互作用。在可预测条件中,重复和切到任务的反应时随着准备时间的增加而减少,但切到代价无显著变化,切离任务的反应时不受准备时间的影响,切离代价表现出反准备效应;不可预测条件下,三种任务的反应时都随着准备时间的增加而减少,但是切到和切离代价表现出反准备效应;（2）切离任务的反应时和代价显著高于切到任务的反应时和代价;（3）在这两种条件下,都没有出现切换代价的准备效应     

The effect of debriefing on laboratory induced helplessness: An attributional analysis1

Debriefing was assessed as means of reversing helplessness deficits through reattribution. Fifty-five subjects listened to escapable or inescapable tones. One inescapable group, prior to anagrams, was debriefed regarding noise uncontrollability. A second inescapable group was administered anagrams by a different experimenter. While exposure to inescapable noise led to performance deficits, switching experimenters obviated these deficits. Debriefing actually facilitated anagram performance. All inescapable subjects—debriefed or not—attributed their lack of control on the noise task to experimenter interference, casting some doubt on reattribution as an explanation of debriefing's effects. Results were discussed in terms of the reformulated learned helplessness model and the ethical implications of debriefing in learned helplessness research.     

Repetition priming of words and pseudowords in divided attention and in amnesia

Repetition priming of novel stimuli (pseudowords) and stimuli with preexisting representations (words) was compared in two experiments. In one, 19 normal male subjects performed a lexical decision task with either focused or divided attention. In another, lexical decision performance was compared between 8 male Korsakoff patients and 8 alcoholic control subjects. In control conditions, repetition speeded responses to both stimulus types. Experimental conditions that minimized the contribution of episodic memory to task performance eliminated reaction time priming for pseudowords but not for words. However, in these same conditions, repetition increased the likelihood that pseudowords would be incorrectly classified. These results indicate that preserved repetition priming effects in amnesia do not solely reflect activation of representations in semantic memory.     

Learned helplessness and the detection of contingency: A direct test

Two studies tested a basic hypothesis of the learned helplessness model: That performance deficits associated with exposure to uncontrollable outcomes are directly mediated by an individual's perception of response-outcome independence. In the first experiment 48 subjects were exposed to noise bursts. For one experimental group, the termination of the noise was response-contingent. For five other groups, noise-burst termination was independent of subjects' responses. These five groups varied in the number of trials on which they received positive feedback: As predicted, subjects overestimated the amount of control they had over noise termination as a positive linear function of the amount of noncontingent positive feedback they received. Although subjects exposed to either noncontingent positive or negative feedback showed subsequent performance deficits on an anagrams task, the expected relation between perceived control and subsequent performance failed to emerge. These findings were replicated in a second experiment. In addition, subjects' locus, stability, and globality attributions failed to predict subsequent performance. These results call into question the central premises of helplessness theory: That perceived uncontrollability and causal attributions mediate learned helplessness.     

The debilitating effect of exposure to noncontingent escape: A test of the learned helplessness model

Two studies were conducted to test the hypothesis that exposure to non-contingent escape leads to performance deficits similar to those observed when subjects are exposed to noncontingent aversive outcomes from which there is no escape, and that causal attributions mediate these deficits. Previous attempts to produce “appetitive helplessness” (deficits resulting from exposure to noncontingent positive events) have been plagued by subjects' tendency to believe that they are responsible for positive events. In Experiment 1, 40 subjects were exposed to contingent or noncontingent noise escape trials. As predicted by the learned helplessness model, subjects who received inescapable noise performed less well on a subsequent anagram task than subjects exposed to escapable noise. Similarly, subjects who escaped from the noise owing to the benevolence of a powerful other rather than because of their own efforts, showed performance deficits paralleling those of the inescapable noise subjects. In Experiment 2, subjects who escaped an aversive tone through no effort of their own showed subsequent performance deficits, but globality of their self-reported attributions did not predict subsequent anagram performance. The results of these studies provide support for the hypothesis that uncontrollability, independent of the valence of a particular outcome, is responsible for helplessness deficits, but do not support the mediational role of attributions, at least in the laboratory.     

Control motivation and attributions for performance

Two experiments examined the relationship between the desire for effective control over performance outcomes and attributions of causality for those outcomes. In Experiment 1, subjects were led to believe that they had either succeeded at or failed a test that was either unimportant or important. As predicted, failure of the important test was attributed more to lack of effort (a controllable cause) and less to lack of ability (an uncontrollable cause) than was failure of the unimportant test. In Experiment 2, all subjects were led to believe that they had failed a test. Once again, subjects were informed that the test was either important or unimportant. In addition, half the subjects were told that they would be undergoing more tests in a later testing session, while half were not informed of any future testing. As in Experiment 1, subjects failing the important test attributed their failure less to lack of ability than did subjects failing the unimportant test. The anticipation of future testing interacted with test importance in its effects on attributions to ability. Subjects performing the unimportant task attributed their failure more to lack of ability when anticipating future performance than when not. Attributions of subjects performing an important task were not affected by the anticipation of future performance. Results were discussed in terms of the need for control over performance outcomes.     

Effects of attack and uncontrollable noise on aggression

After being either attacked or treated in a more neutral manner by an experimental confederate, male subjects shocked the confederate while being stimulated by loud noise. Among previously attacked subjects, possession of control over offset of the noise led to the delivery of shocks significantly shorter in duration than those given by subjects who did not have control. Mere predictability of noise offset did not have the same effect. Subjects who could control the noise did not differ from those who heard no noise with respect to the duration of shocks given. Noise had no effect on shock duration among nonattacked subjects. In a follow-up study subjects who were given bogus information that they were aroused by noise were less punitive toward an attacking confederate than subjects given no such information. The overall conclusion is that noise facilitates aggression in subjects who have been instigated to aggress to the degree that noise-produced arousal is misattributed to the instigating stimulus.     

The effects of reward and punishment on reaction times and autonomic activity in hyperactive and normal children

The performance of hyperactive and control children was compared on a delayed reaction time task under three reinforcement conditions: reward, punishment, and reward plus punishment. Hyperactives had slower and more variable reaction times, suggesting an attentional deficit. Although each of the three reinforcement conditons was successful in improving reaction times for both subject groups, reward led to a significant increase in impulsive responses in the hyperactive children. Autonomic data revealed that reward also increased arousal to a greater extent than punishment or reward plus punishment. Although resting skin conductance was not different in the two groups of subjects, hyperactives produced fewer specific autonomic responses to signal stimuli.     

Task predictability and remembered duration

The effects of structural predictability on remembered duration judgments were examined within the context of the performance of a series of highly familiar tasks. Across a set of three experiments, task predictability was manipulated by the presence or absence of advance expectancies of what tasks were to be performed (Experiment 1), an (in)variant ordering of task performance (Experiment 2), and the placement of interruptions at between- versus within-task locations (Experiment 3). In each case, a higher degree of predictability led to more accurate and reliable duration estimates that were relatively free of bias, while uncertainty decreased accuracy through an overestimation bias. These results not only render insight into the mediational mechanisms responsible for temporal judgments, but also sug-gest some practical applications for everyday behavior.     

Effects of jet engine noise and performance feedback on perceived workload in a monitoring task

This study examined the effects of exposure to intermittent jet aircraft noise (70 dBA or 95 dBA maximum intensity) and knowledge of results concerning signal detections (hit-KR) on performance efficiency and perceived workload in a 40-min visual vigilance task. The noise featured a Doppler-like quality in which planes seemed to approach from the monitor's left and recede to the right. Perceptual sensitivity (d') was poorer in the context of noise than in quiet but only in the presence of hit-KR. The lack of noise-related performance differences in the absence of hit-KR most likely reflected a "floor effect" rather than some special relation between noise and feedback. When compared to subjects performing in quiet, those who operated in noise were less able to profit from hit-KR, a result that may reflect the effects of noise on information processing. In addition to its negative effects on signal detectability, noise elevated the perceived workload, as measured by the NASA-TLX. This effect was robust; it was independent of the presence of hit-KR, even though hit-KR generally lowered the overall level of perceived workload. The results provide the initial experimental demonstration that perceived workload is a sensitive measure of the effects of aircraft noise in monitoring tasks.     

Discrete and contextual cue alterations eliminate the instrumental appetitive-to-aversive transfer impairment in phenytoin-treated rats

We have shown previously that the antiepileptic phenytoin impairs transfer in an instrumental learning task (Banks et al., 1999). The present study examined the effects of contextual alterations on appetitive-to-aversive transfer performance of rats treated with either phenytoin or tang. Adult rats were tested in tone-signaled appetitive and aversive instrumental tasks, where the animal bar-pressed to obtain a food reward (sugar pellet) or to avoid shock. Rats were trained on the appetitive task for 31 days. Beginning on the twenty-first day, rats were gavaged with either phenytoin or tang twice daily. Animals were then transferred to aversive training, with the phenytoin or tang treatment continuing throughout the 25 testing days. For some animals, contextual changes were introduced as they shifted from appetitive to aversive training, while for other animals these changes were not made. Phenytoin-treated rats that were presented with changes in context as they transferred from the appetitive to the aversive task learned the avoidance response to levels substantially higher than drug-treated rats not presented with the contextual changes. These results indicate that phenytoin impairs avoidance learning following transfer from the appetitive task, and that this impairment can be eliminated by introducing changes in context at the point of transfer. In the tang-treated control subjects, on the other hand, there was no improvement in transfer learning performance associated with the changes in contextual cues. This pattern of results suggests that contextual encoding processes in rats being trained in an instrumental appetitive-to-aversive paradigm are dramatically affected by phenytoin.