The association between stress, hemispheric specialization, and callosal interactions

This study examines the effects of stress on hemispheric specialization and callosal transfer. Previous research suggests that the two cerebral hemispheres are asymmetric in their regulation of and response to stress. Further, studies have suggested that the activity of the corpus callosum may also be affected by stress. A group of 28 participants completed the Spielberger State-Trait Anxiety Inventory and performed a bilateral Stroop task. The bilateral Stroop task contains separate conditions which measure both hemispheric specialization and callosal transfer. A significant correlation was found between state anxiety and our measure of callosal transfer. Specifically, those individuals with greater state anxiety experience more efficient callosal transfer than did those with lower state anxiety. We conclude that state anxiety enhances callosal transfer without affecting hemispheric specialization.     

The effects of instruction and environmental demand on state anxiety,driving performance and autonomic activity: Are ego-threatening manipulations effective?

A small yet emerging body of research on the relationship between anxiety and driving suggests that higher levels of state anxiety may lead to more dangerous driving behaviours. The aim of the current research was to investigate the effects of increased state anxiety on driving behaviours within a simulated environment using instructional sets to manipulate anxiety levels. In Study One, whilst a set of safety-related instructions were able to increase state anxiety, this did not result in changes to driving behaviours. In Study Two, ego-threatening instructions were not able to successfully increase state anxiety. This has implications regarding instructional sets in research, including their task relevance and the necessity for a motivational incentive. However, when changes in anxiety were considered regardless of instruction group, Study Two found changes in SDLP and skin conductance levels related to state anxiety increases. As these effects were context specific, it is argued that some of these changes may be due to poorer processing efficiency, leading to suggestions about the types of behaviours that may need to be trained in potential therapies for those who show high state anxiety levels whilst driving.     

Perceptual-motor learning benefits from increased stress and anxiety

The purpose of this study was to manipulate psychological stress and anxiety to investigate effects on ensuing perceptual-motor learning. Thirty-six participants attended two experimental sessions separated by 24 h. In the first session, participants were randomized to either a mental arithmetic task known to increase stress and anxiety levels or a control condition and subsequently completed training on a speeded precision pinch task. Learning of the pinch task was assessed at the second session. Those exposed to the high stress-anxiety mental arithmetic task prior to training reported elevated levels of both stress and anxiety and demonstrated shorter movement times and improved retention of movement accuracy and movement variability. Response execution processes appear to benefit from elevated states of stress and anxiety immediately prior to training even when elicited by an unrelated task.     

Trait anxiety,visuospatial processing,and working memory

This experiment assessed the components of Baddeley's working memory system impaired by anxiety during performance of the Corsi Blocks Test. The Corsi task was performed concurrently with different secondary tasks (i.e., articulatory suppression; counting backwards; spatial tapping; simple tapping). Results showed Corsi performance depended mainly on the central executive and visuospatial sketchpad components of working memory. Adverse effects of trait anxiety on the Corsi task were observed on the central executive but not on the phonological loop or the visuospatial sketchpad. These effects were not mediated by state anxiety. The findings indicate for the first time that trait anxiety impairs central executive functioning on a nonverbal task, and that anxiety does not impair functioning of the “slave” systems (i.e., phonological loop; visuospatial sketchpad). Theoretical implications of these findings are discussed.     

Attentional bias to threat: Roles of trait anxiety, stressful events, and awareness

Attentional biases for threat stimuli were assessed in high and low trait anxious subjects (n = 66) using a probe detection task. To examine the effects of trait anxiety and situational stressors, each subject was tested three times: Under no stress, laboratory-induced stress, and examination-induced stress. To evaluate the role of awareness, half the word stimuli were presented very briefly (14 msec) and masked, and the other half were presented for 500 msec without a mask. Results showed that high trait anxious subjects under exam stress showed an attentional bias towards unmasked threat stimuli compared with low trait subjects. This effect was not found under lab-induced stress, suggesting that the attentional bias for unmasked threat in high trait subjects may be a function of a prolonged stressor, rather than a transient increase in state anxiety. The results from the masked exposure condition were not predicted; high trait anxious subjects shifted attention towards the spatial location of threat words despite lack of awareness of their lexical content, but this bias was only apparent in the no-stress condition. The results are discussed in relation to recent cognitive theories of anxiety.     

Effects of stress and anxiety on the processing of threat stimuli

Two experiments extended the work of MacLeod and Mathews (1988) and examined whether a cognitive bias for threat information is a function of state or trait anxiety. Color-naming and attention deployment tasks were used to assess the effects of a stress manipulation procedure on attentional responses in high and low trait anxious subjects. Subjects under high stress selectively allocated processing resources toward threat stimuli, irrespective of their trait anxiety level. There was no consistent evidence of a cognitive bias associated with trait anxiety, and the effect of the stress manipulation did not appear to be mediated by state anxiety. It was suggested that trait factors do not modify attentional biases associated with acute stress, but may influence such biases when stress is prolonged.     

The effects of an appraisal manipulation: Affect,intrusive cognitions,and performance for two cognitive tasks

We examined the relationship between trait measures of general appraisal and test anxiety, state measures of stress appraisals, affect, and intrusive cognition, and performance measures on two cognitive tests (mental math and Raven matrices). Participants were randomly assigned to threat, challenge, or control conditions that were created by manipulating both primary and secondary appraisals. We predicted that the threat condition would lead to more negative affect, stress appraisals, intrusive cognitions, and more errors. While our manipulated conditions led to inconsistent effects, path analyses tended to confirm predictions that negative task appraisals and trait test anxiety lead to negative affect and to intrusive cognitions, and that for mental math test performance a path from intrusive cognitions to test errors was established. The importance of understanding dispositionaland situational variables and their interactions during stress encounters are discussed, as is future research involving the general appraisal dimension. The authors wish to thank the many students who acted as experimenters and helped with data entry. Thanks go to James Johnson, Ann Schuller, and Brandon Vancura for all their hard work. Special thanks go to Roger Lott for his expert performance as the main investigator in the threat and challenge conditions. An enormous debt of gratitude also goes to my wife Kathy for all her patience and support, and for her help with the audio tapes used in this study. This study was completed as partial fulfillment of the requirements for a Master’s Degree for the first author. Portions of this work will be presented at the annual meeting of the Midwestern Psychological Association, 1997.     

Go no-go performance under psychosocial stress: beneficial effects of implementation intentions

Acute stress has been found to have negative and implementation intentions (IIs) to have positive effects on cognitive performance. This study was the first to examine the effects of IIs on executive action control under acute psychosocial stress. Forty-two male subjects aged 21-39 years were randomly assigned to the Trier Social Stress Test (TSST) versus a rest condition. In addition, the instruction to the executive task (a go no-go task) was manipulated (IIs versus standard instruction). After the stress test, a dual-task procedure including a go no-go task was conducted. The TSST resulted in increases in cortisol response, heart rate and state anxiety compared to the rest condition. Acute stress significantly impaired go no-go performance, but only in the group without IIs. We conclude that under acute stress conditions executive functioning is reduced, but the use of IIs can be an effective strategy to overcome this negative effect.     

Moderating factors explaining stress reactions: comparing chronic-without-acute-stress and chronic-with-acute-stress situations

The author compared patterns of moderating factors explaining stress reactions during 2 states: chronic-without-acute-stress and chronic-with-acute-stress. She hypothesized that personal dispositions would contribute more to understanding stress reactions during a prolonged stress state than during an acute state. The participants were Israeli Jewish adolescents living in West Bank settlements during the prolonged (chronic-without-acute-stress) state of the intifada (the Palestinian uprising against Israeli occupation) and during the chronic-with-acute-stress state, immediately after the assassination of Prime Minister Rabin. The author examined 5 variables as moderating factors--trait anxiety, sense of coherence, cognitive appraisal of the political situation, family sense of coherence, and sense of community--and measured 2 stress reactions--state anxiety and psychological distress. Data were collected from 266 8th-grade students during the chronic-without-acute-stress state and 448 students at the same grade level at the chronic-with-acute-stress state. The overall magnitude of variance explanation was different at each state: The author found a relatively high explained variance of state anxiety and psychological distress in the chronic-without-acute-stress situation but not in the chronic-with-acute stress state. These data support the value of developing a model that would recognize the different types of stress situations for moderating the effects of stress.     

STRESS AND PERFORMANCE: EFFECTS OF SUBJECTIVE WORK LOAD AND TIME URGENCY1

Subjective work load, time urgency, and other stress/motivation variables were measured for management personnel taking a demanding problem-solving exam at the end of a two-week training course. Comparing measures of precourse ability and final exam performance, the primary findings were that the corrected performance scores had strong negative linear (not inverted-U) relations with both subjective work load and time urgency. General state anxiety and task involvement did not substantially relate to performance. The results are discussed in terms of the nature of this particular task and the predictions of various stress/performance theories. In problem solving or other tasks requiring novel responses, these data suggest that increases in psychological stresses like subjectively high work load and time urgency uniformly impair performance across the whole range of these variables.     

Efficacy of self-instructional training for reducing children''s anxiety in an evaluative situation

Fifty-six fourth-grade children were categorized as either high or low in trait anxiety and then assigned to a self-instruction treatment, minimal-treatment, or no-treatment control condition. At both pretest and posttest, the subjects recited a memorized poem while being videotaped with the expectation that they would be judged on their performance. State anxiety measures, a behavior rating of anxiety, a measure of performance accuracy and the time involved in reciting a poem were obtained at both pretest and posttest. Contrary to expectation, the self-instructional training resulted in subjects' exhibiting greater signs of behavioral anxiety, subjects' hurrying through the task (taking less time to recite the poem) and high trait-anxiety subjects' reporting more state anxiety while anticipating reciting the poem. Correlational analyses indicated that trait anxiety was significantly related to the measures of state anxiety and the behavior rating of anxiety but not to performance accuracy.     

状态焦虑与转换功能：注意控制理论在运动员群体中适用性的检验

通过3个平行实验探讨了状态焦虑对转换功能的影响,检验了注意控制理论在运动领域的适用性。3个实验采用不同范式的More-Odd shifting任务测量转换功能,其结果呈现一致的趋势：在大学生群体中,高状态焦虑降低了加工效能,而对正确率影响不大;而在运动员群体中,高状态焦虑对加工效能和正确率都影响不大。本研究得出结论：注意控制理论关于状态焦虑影响转换功能的假设可能在不同群体中有不同的适用性,适用于大学生,但不适用于运动员。     

The effects of stress on state and trait anxiety in emotionally disturbed,normal, and delinquent children

The effects of stress on trait and state anxiety of emotionally disturbed, normal, and delinquent children were assessed using the State-Trait Anxiety Inventory for Children (STAIC). This scale measures both transitory feelings of apprehension and tension that vary over time as a function of situational stress (A-State) and individual differences in the disposition to experience such anxiety states (A-Trait). Results indicated that A-State increased as a function of stress, whereas A-Trait was relatively stable and impervious to the temporary effects of stress. Use of the STAIC with normal and deviant populations was supported.     

急性应激损害对威胁刺激的注意解除

急性应激会增强个体对威胁刺激的注意偏向, 但急性应激是增强了对威胁刺激的注意定向还是损害了对威胁刺激的注意解除还不清楚。本研究采用社会评估冷压任务和点探测任务, 结合事件相关电位技术, 考察急性应激对威胁刺激注意偏向影响的认知机制。在进行社会评估冷压任务后, 应激组个体的状态焦虑和皮质醇浓度显著升高。在注意偏向中, 应激组对威胁刺激的注意解除比控制组更慢, 应激组和控制组在对威胁刺激的注意定向上无显著差异。ERP结果上, 威胁刺激诱发应激组比控制组产生了更负的SPCN, 在N2pc上没有显著差异。应激组和控制组皮质醇增量的差异和N2pc、SPCN的组间差异均有显著正相关。这些结果说明, 急性应激增强对威胁刺激的注意偏向是因为其损害个体对威胁刺激的注意解除, 这可能是因为急性应激损害了与注意解除相关的额-顶网络的功能所致。     

Effects of dogmatism on state anxiety during the analysis and synthesis of new beliefs.

Investigated the concept of dogmatism as a defense mechanism and the role of threat in the synthesis of new beliefs by examining the effects of dogmatism on changes in state anxiety (A-State) during the analysis and synthesis of new beliefs. Sixty female college students were selected on the basis of extreme scores on the Dogmatism Scale and the trait anxiety (A-Trait) scale of the State-Trait Anxiety Inventory to work on a task requiring the analysis and synthesis of new beliefs. In support of Rokeach's theory, high dogmatics displayed no change in A-State from the analysis to the synthesis period of the task, while low dogmatics exhibited a significant decline in A-State between the two periods. The clinical implications of these findings were discussed in terms of the role of dogmatism in the processing of personality interpretations and test feedback.     

An integrative approach to leadership and social support

This study examined the effects of instrumental and socio-emotional behaviors of friends on stress reactions and task performance. A 2 (presence or absence of instrumental behavior) * 2 (presence or absence of socio-emotional behavior) * 2 (high or low legitimacy of influence) factorial design was used. Ninety-one college-age females as subjects and their close same-sex friends as confederates participated together in the experiment. Dependent variables were mean blood pressure (MBP) as a physiological stress reaction, state anxiety as a psychological stress reaction, and the level of performance in a simple arithmetic task. Instrumental behavior had a facilitating effect on task performance in the high legitimacy condition. Socio-emotional behavior showed a buffering effect on physiological stress reaction when the friend did not engage in instrumental behavior in the low legitimacy condition. These findings suggest that legitimacy of influence may be able to explain the differences between leadership and social support processes.