Frontal brain oscillations and social anxiety: A cross-frequency spectral analysis during baseline and speech anticipation

Increasing evidence suggests that cross-frequency spectral coupling between slow (SW) and fast (FW) wave activity in the EEG supports information exchange between separate and functionally distinct neural systems. Further, evidence suggests that states of uncertainty, anticipation and anxious apprehension involve a high degree of SW-FW coupling. We examined whether adults pre-selected for high and low social anxiety showed distinct patterns of frontal brain oscillatory coupling during resting baseline and the anticipation of a self-presentation task. As predicted, the high socially anxious group showed significantly greater SW-FW coupling than the low socially anxious group, in the right, but not left, frontal electrode sites while anticipating a public speaking task. Additionally, the low socially anxious group showed a decrease in delta power from baseline to speech anticipation, suggesting that they found the same task potentially rewarding. Exploratory analyses indicated no effects of delta-gamma coupling. However, EEG gamma band power increased during the speech anticipation condition, in the parietal electrode sites. Our results are discussed in the context of previous studies on cross-frequency EEG coupling in relation to individual differences in motivation and emotion and future directions for studying the neural correlates of anxiety.     

Preparatory ERPs in visual,auditory, and somatosensory discriminative motor tasks

Previous event-related potential (ERP) studies mainly from the present research group showed a novel component, that is, the prefrontal negativity (pN), recorded in visual-motor discriminative tasks during the pre-stimulus phase. This component is concomitant to activity related to motor preparation, that is, the Bereitschaftspotential (BP). The pN component has been reported in experiments based on the visual modality only; for other modalities (acoustic and/or somatosensory) the presence of the pN warrants further investigation. This study represents a first step toward this direction; indeed, we aimed at describing the pN and the BP components in discriminative response tasks (DRTs) for three sensory modalities. In experiment 1 ERPs were recorded in 29 adults in visual and auditory DRT; an additional group of 15 adults participated to a somatosensory DRT (experiment 2). In line with previous results both the pN and the BP were clearly detectable in the visual modality. In the auditory modality the prefrontal pN was not detectable directly; however, the pN could be derived by subtraction of separate EEG traces recorded in a “passive” version of the same auditory task, in which motor responses were not required. In the somatosensory modality both the pN and the BP were detectable, although with lower amplitudes with respect to other two sensory modalities. Overall, regardless of the sensory modality, anticipatory task-related pN and BP components could be detected (or derived by subtraction) over both the prefrontal and motor cortices. These results support the view that anticipatory processes share common components among sensory modalities.     

大学生焦虑人群情绪冲突反应的脑功能网络研究

利用基于图论的复杂网络分析方法,对脑网络的拓扑结构和属性进行分析, 探讨大学生焦虑人群情绪冲突反应的脑功能网络特点。选取焦虑组和正常对照组各16名志愿者,进行情绪词-面孔stroop冲突任务,同步记录 64导脑电(EEG)数据。分别对beta(14～30 Hz)和高gamma(50～80 Hz)节律的EEG数据进行同步似然分析,选择合适阈值构建脑网络拓扑结构,并计算网络的节点度和聚类系数。结果显示,在 beta 和高gamma 节律中,焦虑组额叶、颞叶及顶叶等脑区存在异常连接,额叶和顶叶的节点度均小于正常组的数值(P <0.05),而颞叶的节点度均高于正常组的数值(P <0.05)(如在beta节律,焦虑组额叶FP1、顶叶CP1和颞叶T7电极处的节点度分别是5.21±0.62、6.25±0.53、7.91±0.71,而正常组的节点度分别为10.42±1.53、7.94±0.55、3.55±0.36),表明焦虑人群额顶叶功能减弱而颞叶功能异常增强;焦虑组脑网络的聚类系数低于正常组的值(P <0.05)(焦虑组 beta 和高gamma 节律的聚类系数分别是0.523 8±0.039 2、0.586 4±0.055 8,而正常组分别为0.603 2±0.071 1、0.664 7±0.060 1),表明焦虑人群的脑网络内部集团化程度、网络的信息传输能力下降。通过研究,为探索焦虑症、抑郁症等心理、精神类疾病的神经机制提供新的视角。     

Social anxiety and self-evaluation of social performance in a nonclinical sample of children.

In an investigation of socially anxious children's social behavior and self-evaluation, 28 high socially anxious and 28 low socially anxious children, ages 11 to 13 years, appraised their performance before and after participating in a role-play task. Half of the children were given video feedback prior to giving their posttask self-evaluations. High socially anxious children anticipated poorer performance on the role-play task, and some group differences in observed social performance were evident. Self-evaluations from video feedback only improved for the high socially anxious children who displayed more eye contact, gave longer verbal responses, and used more constructive verbal strategies in the role-play scenarios.     

The influence of anxiety on electrodermal responses to distractors.

Contrary to classical expectation, anxiety has been repeatedly observed to be associated with reduced electrodermal activity. This could be the result of successful coping. In line with this interpretation, high-trait anxious individuals performing moderately arousing tasks were expected to manifest a reduced responding to distractors, since this is an adaptive outcome. High- and low-trait anxious participants had to perform a visual search task in a low-stress context. Unrelated neutral and emotional auditory words served as distractors. As a control, neutral and emotional words were also delivered in a no task condition. Skin conductance responses (SCRs) were greater during the task than during the control phase, but in the high anxious group, this increase in SCRs was smaller following emotional distractors than following neutral ones. Moreover, SCRs to both types of words habituated, but the results suggested that only the low-trait anxious participants presented the classical slowing of SCRs habituation when performing the task. All these data are interpreted as an illustration of a resource-based electrodermal inhibition in the high-trait anxious participants. It sustains the idea that mild to moderate anxiety may increase the mastery of situations.     

A brief positive psychological intervention prior to a potentially stressful task facilitates more challenge‐like cardiovascular reactivity in high trait anxious individuals

When confronted with stress, anxious individuals tend to evaluate the demands of an upcoming encounter as higher than the available resources, thus, indicating threat evaluations. Conversely, evaluating available resources as higher than the demands signals challenge. Both types of evaluations have been related to specific cardiovascular response patterns with higher cardiac output relative to peripheral resistance indicating challenge and higher peripheral resistance relative to cardiac output signaling threat. The aim of this research was to evaluate whether a brief positive psychological exercise (best possible selves intervention) prior to a potentially stress‐evoking task shifted the cardiovascular profile in trait anxious individuals from a threat to a challenge type. We randomly assigned 74 participants to either a best possible selves or a control exercise prior to performing a sing a song stress task and assessed their level of trait anxiety. Cardiac output (CO) and total peripheral resistance (TPR) were continuously recorded through baseline, preparation, stress task, and recovery, respectively, as well as self‐reported affect. Trait anxiety was related to higher CO in the best possible selves group and lower CO in the control group. While high trait anxious individuals in the control group showed increasing TPR reactivity, they exhibited a nonsignificant change in the best possible selves group. Moreover, in the latter group a stress‐related decrease in positive affect in high trait anxious participants was prevented. Findings suggest that concentrating on strengths and positive assets prior to a potentially stressful encounter could trigger a more adaptive coping in trait anxious individuals.     

False Heart Rate Feedback and the Perception of Heart Symptoms in Patients with Congenital Heart Disease and Anxiety

Background  Little is known about the mechanisms explaining an increased perception of heart symptoms in congenital heart disease (ConHD). In the present study, it was suggested that a combination of high trait anxiety and disease history increases the perception of heart symptoms. Purpose  It was tested whether false heart cues will result in an increased perception of heart symptoms in patients with ConHD and anxiety. Method  Thirty-six patients with ConHD and 44 healthy controls performed two exercise tasks. During one of the exercise tasks, participants were exposed to a false heart cue consisting of false heart rate feedback (regular or irregular). Perceived heart symptoms were assessed and heart rate, arterial partial pressure of CO₂, and respirator rate were monitored continuously. Results  In line with the predictions, false heart rate feedback resulted in an increased perception of heart symptoms in high trait anxious patients with ConHD that could not be explained by acute heart dysfunction. However, unexpectedly, this effect was not observed immediately after the false heart rate feedback task but after a second exercise task without false feedback. Conclusion  The results suggest that not the sole presence of ConHD but ConHD in combination with high trait anxiety results in a vulnerability to overperceive heart symptoms.     

Specificity of regional brain activity in anxiety types during emotion processing

The present study tested the hypothesis that anxious apprehension involves more left- than right-hemisphere activity and that anxious arousal is associated with the opposite pattern. Behavioral and fMRI responses to threat stimuli in an emotional Stroop task were examined in nonpatient groups reporting anxious apprehension, anxious arousal, or neither. Reaction times were longer for negative than for neutral words. As predicted, brain activation distinguished anxious groups in a left inferior frontal region associated with speech production and in a right-hemisphere inferior temporal area. Addressing a second hypothesis about left-frontal involvement in emotion, distinct left frontal regions were associated with anxious apprehension versus processing of positive information. Results support the proposed distinction between the two types of anxiety and resolve an inconsistency about the role of left-frontal activation in emotion and psychopathology.     

The Regulation of Blood Pressure Reactions to Taxing Conditions using Pulse Transit Time Feedback and Relaxation

Two experiments are described in which 40 normotensive subjects were trained to reduce blood pressure (BP) both in undistracting conditions and while performing taxing tasks. Biofeedback was compared with relaxation in each case, and BP was continously monitored by the pulse wave velocity method. In Study 1, feedback and relaxation groups produced similar BP reductions when control was attempted in isolation. However, the relaxation group was significantly disturbed during performance of an auditory choice reaction time (RT) task. In contrast, feedback subjects showed identical BP modifications in the two conditions. In Study 2, the differences during the RT task proved to be short lived. However, the feedback group overcame pressor reactions to a mental arithmetic test more rapidly than could relaxation subjects, and the difference between groups persisted during no-feedback trials. In both studies, modifications were more specific in the feedback condition, since alterations in heart rate, respiration and general activity were less prominent. It is suggested that it may be fruitful to use feedback for training people to overcome BP reactions to taxing conditions, rather than trying to modify tonic level alone.     

Effects of social anxiety and evaluative threat on cardiovascular responses to active performance situations

This study investigated the joint influence of trait social anxiety and evaluative threat on psychological and cardiovascular responses to active coping situations. Fifty-two normotensive female students characterized as either high or low in trait social anxiety performed a mental arithmetic task and a speech task requiring persuasive behavior in a context of high or low evaluative threat. Trait social anxiety exerted a substantial influence on cardiovascular reactivity. High socially anxious individuals overall exhibited greater heart rate reactivity. For systolic and diastolic blood pressure enhanced reactivity of socially anxious individuals was confined to low evaluative threat. At high levels of evaluative threat no group differences were observed due to somewhat attenuated reactivity in high compared to low socially anxious individuals. Cognitive appraisals and affective arousal were not found to mediate the effects of social anxiety on cardiovascular reactivity. Results were attributed to differences in effort expenditure rather than experienced anxiety.     

Differences in mental task performance and slow potential shifts in subjects differing in cortisol level.

Hormones of the pituitary-adrenocortical axis (e.g., cortisol) are involved in the regulation of brain function. This study was aimed to clarify whether individual differences in baselines of cortisol are related to differences in heart rate (HR), slow brain potential shifts (SPS), performance data and personality. 17 males were instructed to solve 120 arithmetical tasks under time stress conditions. They could obtain monetary bonuses according to the accuracy of their task performance. This test condition was compared to a control condition. To determine the plasma level of cortisol by radioimmunoassays four blood samples were collected during the session. Baselines were estimated twice. A clustering procedure with respect to all cortisol levels resulted in a group of high responders (HC, n = 9) and a group of low responders (LC, n = 8). The HR was significantly higher in the HC group. The SPS of the LC group were characterized by a larger P300 elicited by the task followed by a steep negative slow wave (NSW) as compared to the HC group. LC subjects also showed a higher NSW before feedback presentation. The LC group solved the tasks faster and obtained more than twice the reward than the other group. They scored higher in achievement motivation and also reported increased 'Social Acceptance' and decreased 'Tiredness'. In sum, the results suggest a more efficient regulation of the arousal level of the LC group in contrast to the HC group as far as reflected in the parameters analysed.     

Social anxiety in adolescents: the effect of video feedback on anxiety and the self‐evaluation of performance

Background: A negative self‐generated image is thought to play a role in the development and maintenance of social anxiety. Video feedback (VF) is an effective therapeutic technique for correcting this distorted image with adults during stressful social tasks. This study investigated the effectiveness of VF with adolescents. Method: Thirty‐six highly socially anxious adolescents (13 to 17‐year‐olds) were randomly assigned to one of two groups: VF or no VF. Both groups gave two brief speeches to a video camera. Self‐rated measures of anticipatory anxiety, predicted performance and actual performance during the speeches were completed at several time points. The speeches were also rated by two independent observers. Results: Adolescents who received VF, in comparison with control participants, developed more positive appraisals of their performance during the first speech. Predictions of their performance on the second speech also improved, and a reduction in state anxiety was observed. Furthermore, a more positive appraisal of performance was generalized to the second speech. The independent observers could not distinguish between the participants who received VF and those who did not. Conclusions: When used with socially anxious adolescents, VF may be a beneficial therapeutic technique in correcting a distorted self‐perception of performance, reducing anxiety prior to entering a stressful social task and enhancing predictions of performance for future tasks. Copyright © 2009 John Wiley & Sons, Ltd.     

The neural correlates of cognitive effort in anxiety: effects on processing efficiency

We investigated the neural correlates of cognitive effort/pre-target preparation (Contingent Negative Variation activity; CNV) in anxiety using a mixed antisaccade task that manipulated the interval between offset of instructional cue and onset of target (CTI). According to attentional control theory (Eysenck et al., 2007) we predicted that anxiety should result in increased levels of compensatory effort, as indicated by greater frontal CNV, to maintain comparable levels of performance under competing task demands. Our results showed that anxiety resulted in faster antisaccade latencies during medium compared with short and long CTIs. Accordingly, high-anxious individuals compared with low-anxious individuals showed greater levels of CNV activity at frontal sites during medium CTI suggesting that they exerted greater cognitive effort and invested more attentional resources in preparation for the task goal. Our results are the first to demonstrate the neural correlates of processing efficiency and compensatory effort in anxiety and are discussed within the framework of attentional control theory.     

Differential responses to mental stress in high and low anxious normal humans assessed by frontal midline theta activity.

The distinct EEG theta rhythm from the frontal midline area observed during performance of mental tasks has been called Fm theta. In the present study, plasma catecholamine responses to mental stress were investigated using male students with (n = 12) and without (n = 12) Fm theta. The subjects were requested to complete the trait anxiety scale of STAI, and control blood samples were obtained. 65 min later, their EEGs were recorded during performance of an arithmetic addition task for 5 min. The state anxiety scores of STAI were obtained twice before and after the EEG recording. Blood samples were drawn three times during the state anxiety test and the EEG recording. The Fm theta appearance group showed low trait anxiety and a decrease of state anxiety after the mental task; however, the Fm theta non-appearance group exhibited high trait anxiety and no changes of state anxiety before and after the mental task. The concentrations of DA, HVA, NA and MHPG in the Fm theta appearance group showed lower levels at all times compared to those in the non-appearance group. In the Fm theta appearance group, an increase of DA turnover was observed by the addition of mental task. On the other hand, the Fm theta non-appearance group showed an increase of NA turnover.     

Biased perception and interpretation of bodily anxiety symptoms in childhood social anxiety

Cognitive models of social phobia (SP) and empirical evidence in adults suggest that affected individuals overestimate arousal symptoms such as heart rate (HR) during social stress and worry about their visibility in public. To date, little is known about these aspects in childhood social anxiety, an important precursor of the disorder. We assessed perception of--and worry about--HR visibility, actual HR, and subjective anxiety during public speaking in high socially anxious (HSA; n = 20) and low socially anxious (LSA; n = 20) Caucasian children, aged 10 to 12 years. Symptom visibility was manipulated by making a nonveridical HR feedback tone audible only to the participant (private condition, HR sounds via headphone) or to participant and observers (public condition, HR sounds via speakers). Further, we assessed interoceptive accuracy in a heartbeat counting task. As expected, HSA children perceived their HR as higher than LSA children in both private and public conditions despite similar actual HR and comparable interoceptive accuracy. Public feedback led to more worry about HR visibility only in HSA but not in LSA children. Biased perception and interpretation of bodily anxiety symptoms during social stress manifests early in social anxiety and might therefore play a crucial role in the aggravation of social anxiety and the development of SP. We discuss implications for current theory, clinical practice, and prevention.     

Frontal electrocortical and cardiovascular reactivity during happiness and anger

The present study investigated electrocortical and cardiovascular reactivity during positive and negative emotion, and examined the relation of asymmetric frontal lobe activation to cardiovascular responses. Participants were 30 healthy, right-handed university students (mean age, 23.9; 60% female; 76% Caucasian). Electroencephalographic (EEG), blood pressure (BP), and heart rate (HR) responses were assessed while subjects engaged in laboratory tasks (personally-relevant recall tasks and film clips) designed to elicit happiness or anger. Happiness-inducing tasks evoked more prominent left than right frontal EEG activation, and greater left frontal EEG activation than anger-inducing tasks. However, anger-inducing tasks were, on average, associated with comparable left and right frontal EEG activation. Irrespective of emotional valence, cardiovascular activation was more pronounced during personally-relevant recall tasks than during the viewing of film clips. During anger recall, both greater left frontal EEG response (r=-0.46, P<0.02) and greater right frontal EEG response (r=-0.45, P<0.02) were correlated significantly with increased HR reactivity during the task. In addition, a right lateralized frontal EEG response during anger-inducing tasks was associated with greater concomitant systolic BP (P<0.03) and diastolic BP (P<0.008) reactivity. Exploratory analyses also indicated that men who displayed a left lateralized frontal EEG response during happiness-inducing tasks showed the greatest concomitant systolic BP and HR reactivity (P's<0.03). These findings suggest that asymmetric frontal EEG responses to emotional arousal may elicit different patterns of cardiovascular reactivity in healthy adults.     

Autonomic recovery and habituation in social anxiety

Growing evidence suggests that, contrary to expectation, high trait socially anxious (HTSA) and low trait socially anxious (LTSA) individuals show comparable autonomic reactivity during stressful speech tasks. To test the hypothesis that autonomic differences between groups might emerge during recovery or habituation, 35 HTSA and LTSA participants gave two impromptu speeches. Measures of anxiety experience as well as cardiovascular, electrodermal, respiratory, and vagal activation were obtained. Despite greater reports of anxiety experience in the HTSA versus the LTSA participants, autonomic measures showed comparable reactivity, habituation, and recovery in the two anxiety groups. These results suggest minimal autonomic differences between HTSA and LTSA individuals, thus supporting theories of social anxiety that emphasize cognitive factors.     

The temporal course of the influence of anxiety on fairness considerations

This study investigated the potential causes of anxious people's social avoidance. The classic ultimatum game was utilized in concert with electroencephalogram recording. Participants were divided into two groups according to levels of trait anxiety as identified by a self‐report scale. The behavioral results indicate that high‐anxious participants were more prone to reject human‐proposed than computer‐proposed unequal offers compared to their low‐anxious counterparts. The event‐related potential results indicate that the high‐anxious group showed a larger feedback‐related negativity when receiving unequal monetary offers than equal ones, and a larger P3 when receiving human‐proposed offers than computer‐proposed ones, but these effects were absent in the low‐anxious group. We suggest anxious people's social avoidance results from hypersensitivity to unequal distributions during interpersonal interactions.     

Anxious gambling: Anxiety is associated with higher frontal midline theta predicting less risky decisions

In this study, we address the effect of anxiety measured with the State‐Trait Anxiety Inventory (STAI) on EEG and risk decisions. We selected 20 high and 20 low anxious participants based on their STAI trait scores in the upper or lower quartile of the norm distribution and implemented a risk game developed in our laboratory. We investigate if high anxious individuals exert more cognitive control, reflected in higher frontal midline theta (FMT) power when they make a risky decision, and if they act less risky compared to low anxious individuals. Participants played a risk game while we recorded their brain responses via EEG. High anxious participants played less risky compared to low anxious participants. Further, high anxious participants showed higher FMT power immediately before they chose one of two risk options, suggesting higher cognitive control during the decision time compared to low anxious participants. Via a mediation analysis, we show that the effect of anxiety on risk behavior is fully mediated by FMT power. Further, questionnaire responses revealed that high anxious participants rated risk situations as riskier compared to low anxious participants. We conclude that anxious individuals perceive risky situations as riskier and thus exert more cognitive control during their risk choices, reflected in higher FMT power, which leads to less risky decisions.     

Biased attentional behavior in childhood anxiety. A review of theory and current empirical investigation

This review examines the state of current theory and research regarding a relatively new area of study in childhood anxiety: the examination of attentional biases associated with the processing of threatening environmental stimuli. In particular, this paper focuses upon current attempts to extend an information processing framework traditionally associated with childhood psychopathology (i.e., Crick & Dodge [Psychol Bull 115 (1994) 74]) and anxiety-related attentional bias research previously conducted only with adults, to populations of anxious children. First, a thorough discussion of Crick and Dodge's model and its applicability to current theories of anxiety is presented. Although each stage of Crick and Dodge's model is shown to possess correlates with current conceptualizations of anxiety, the research investigations reviewed here focus upon the multiple approaches that have been undertaken to better comprehend anxious children's attentional biases in encoding and subsequent task performance decrements. Specifically, recent investigations of anxious children's attentional performance utilizing Stroop tasks, probe detection tasks, and the relatively new probe localization task are reviewed. A discussion of the disparate findings associated with recent studies of each of these tasks is given, with an eye toward the need to specify the developmental, theoretical, demographic, and clinically relevant characteristics associated with the biased attentional behavior observed among highly anxious children.