|Year : 2021 | Volume
| Issue : 3 | Page : 73-79
Cardiovascular responses to social stress elicited by the cyberball task
Robert Eres1, Isabella Bolton2, Michelle H Lim3, Gavin W Lambert4, Elisabeth A Lambert4
1 Neurodisability and Rehabilitation, Murdoch Children's Research Institute, Royal Children's Hospital; Department of Paediatrics, The University of Melbourne, Parkville, Australia
2 Department of Psychological Sciences, Swinburne University of Technology, Hawthorn, Australia
3 Centre for Mental Health, Swinburne University of Technology; Iverson Health Innovation Research Institute, Swinburne University of Technology, Hawthorn, Australia
4 Iverson Health Innovation Research Institute, Swinburne University of Technology, Hawthorn, Australia
|Date of Submission||27-Apr-2021|
|Date of Acceptance||10-Aug-2021|
|Date of Web Publication||29-Sep-2021|
Dr. Robert Eres
50 Flemington Rd, Parkville, 3052
Source of Support: None, Conflict of Interest: None
Objective: The aim of the current study was to investigate cardiovascular responses to a brief social exclusion stressor, the Cyberball task, and to determine whether individual differences in depression, anxiety, and perceived social isolation moderate physiological stress responses. Methods: Sixty-four participants engaged in the Cyberball task while heart rate, blood pressure, and respiratory rate were continuously measured. Results: Systolic (M = 121.61, SD = 13.34) and diastolic (M = 77.34, SD = 7.56) blood pressure increased significantly during the exclusion condition compared with the rest condition (M = 117.81, SD = 12.71, M = 75.63, SD = 7.39, respectively). Significant correlations were also found between social anxiety (r = −0.25) and depression (r = −0.25) scores with systolic blood pressure from the exclusion condition. Further, participants who reported high depression scores had attenuated cardiovascular responses to social exclusion. Conclusions: Overall, cardiovascular activity were elevated after a brief social stressor, but those with clinically relevant cut off scores on the CES-D had attenuated cardiovascular responses These findings support the growing body of literature surrounding cardiovascular stress reactivity to stress induced from social exclusion.
Keywords: Acute social stress, blood pressure, cardiovascular stress reactivity, cyberball, depression, social exclusion
|How to cite this article:|
Eres R, Bolton I, Lim MH, Lambert GW, Lambert EA. Cardiovascular responses to social stress elicited by the cyberball task. Heart Mind 2021;5:73-9
| Introduction|| |
With the recent COVID-19 pandemic sweeping the globe, there are an increasing number of concerns raised about the psychological stress resulting from social distancing and self-isolating. Research shows that psychological stress is strongly linked with physical disease development and progression, and this appears to be particularly true for cardiovascular disease. Much of the research to date prioritizes cardiovascular responses to acute performance-based stressors, including mental arithmetic tasks and/or the Trier Social Stress Test (TSST), both of which involve performing a task in front of others. Studies that used these stress tasks have shown significant increases in heart rate, and blood pressure, with preferential activation of the cardiac sympathetic outflow.
Another form of social stress comes from relationship victimization. Broadly speaking, relationship victimization can be conceptualized as being the recipient of targeted aggressive acts that disrupt relationships. A common example of this is social exclusion which is theorized to be a deeply threatening social stressor to individuals. Previous investigations on stress responses to social exclusion have typically examined the hypothalamic-pituitary-adrenocortical axis and autonomic reactivity as measures of stress. For example, reduced cortisol and increased alpha amylase are observed in saliva samples when people are socially excluded, compared with included, in the Cyberball task, an ostensible ball throwing game developed to assessed social exclusion.
Although there is substantial evidence that social exclusion can affect the physiological markers associated with stress,,, fewer studies have investigated the cardiovascular responses to social exclusion. In a recent meta-analysis of 120 studies, the Cyberball task was found to produce large effects for eliciting interpersonal and intrapersonal stress, however, there were no studies that investigated cardiovascular outcomes included in the analysis. Since then, two studies have investigated the cardiovascular responses to a brief social stressor, but they have produced mixed findings. For example, Iffland et al. showed increased heart rate and no difference in skin conductance to being socially isolated in the Cyberball task, while in a different study, the same authors showed the inverse effect using the same paradigm. Another study found no difference in cardiovascular reactivity between inclusion and exclusion conditions using the Cyberball task. Therefore, social exclusion needs to be investigated further to determine its influence on cardiovascular responses.
In addition, the presence of mental health symptoms such as social anxiety and depressive symptoms negatively affects an individual's perception of relationships., Loneliness is the subjective negative emotional experience of feeling a discrepancy in our social connections, and has been shown to affect cardiovascular responses to stress. Those who perceive themselves to be socially isolated have different cardiovascular responses to acute stressors compared with people who do not perceive themselves to be isolated. For example, those who perceive themselves to be socially isolated tend to show exaggerated systolic blood pressure and lower heart rate response to acute stressors than those who do not perceive themselves to be socially isolated.
Previous research findings, however, have shown a discrepancy in how perceived social isolation influences cardiovascular reactivity to stress. For example, higher perceived social isolation was associated with high blood pressure responses in an arithmetic stress task but not in a public speaking task. Conversely, perceived social isolation was associated with lower heart rate during a public speaking task but not during a mental arithmetic task. Therefore, the evidence for how perceived social isolation is associated with cardiovascular responses to acute stress is mixed and may be due to the type of stress task employed.
While research into cardiovascular reactivity to stress has primarily focused on mental arithmetic and TSST,, fewer studies have investigated cardiovascular reactivity to relationship victimization stress (e.g. social exclusion). The current study's aim was to determine whether a brief social exclusion task can influence cardiovascular reactivity. If social stress can be elicited using a brief social stressor, we would expect that mood would be negatively impacted after completing the exclusion condition compared with the inclusion. We also expected that cardiovascular stress responses would be elicited for social exclusion conditions but not for social inclusion conditions. Furthermore, because increased depressive symptomatology has been shown to be associated with blunted cardiovascular reactivity to laboratory stressors and exaggerated and blunted physiological reactivity to social exclusion, some participants may be more susceptible to stressful situations depending on their mental health symptoms. Therefore, we also predicted that individual differences, in particular, social anxiety, depression, and perceived social isolation severity would be associated with cardiovascular reactivity.
| Methods|| |
Participants were healthy adults (n = 64, 56% female) aged between 18 and 37 years (Mage = 22.98, SD = 4.52). All participants were fluent in English. Participants were asked to not consume drugs or alcohol 2 days before testing and were required to not be on medication that could alter blood pressure. Participants were also required to not have consumed caffeine for 12 h before the session. Recruitment was via an undergraduate research experience program (42.2%) and convenience sampling of community members. The protocol of this study conformed to the Declaration of Helsinki for human experimentation. All subjects provided written informed consent before participation. The experimental protocol was approved by the university's human ethics committee.
Information on age, gender, living status, working status, relationship status, and ethnicity were collected using a self-report measure. [Table 1] shows details relating to participants.
Perceived social isolation
Perceived social isolation was assessed using the 20-item University of California, Los Angeles Loneliness Scale – Version 3 (UCLA-LS). Participants indicated how often they felt each item on a Likert-type scale ranging from 1 (Never) to 4 (Always). Scores were summed together to create a total score, where higher scores indicated higher levels of perceived social isolation.
The 20-item Centre for Epidemiological Studies–Depression scale was used to assess depression symptomology. Items were measured on a 0 (Rare or none of the time) to 3 (Most or all of the time) Likert-type scale. Scores were summed to create a total score indicative of depression symptomatology, where higher scores indicated the presence of more symptomatology.
The 20-item social interaction anxiety scale was provided to participants, however, only the 17 straightforward items were used for analysis. We used the straightforward items because these items are psychometrically more valid indicators than the reverse items. Items were scored on a Likert-type scale from 0 (Not at all) to 4 (Extremely) and summed to create a total score with higher scores indicating more social anxiety symptomatology.
Positive and negative affect
The 10-item Positive and Negative Affect Scale – State version was used to measure affect before and after the social stress task. Responses were measured on a Likert-type scale from 1 (Not at all) to 5 (Extremely). Higher scores demonstrated higher levels of positive and/or negative affect.
Blood pressure was measured continuously using a calibrated finometer system (Finapress Medical System BV, Enschede, The Netherlands) with values confirmed using a Dinamap monitor (Model 1846SX, Critikon Inc, Tampa, FL, USA). Heart rate was determined using a three-lead echocardiogram and a respiration belt was used to measure respiratory rate. Blood pressure, heart rate, and respiratory rate were digitized with a sampling frequency of 1000 Hz using PowerLab recording system, model ML 785/8SP (ADI Instruments) as previously described.
Social exclusion task
The Cyberball task was used to simulate social inclusion and exclusion scenarios. During the Cyberball task, participants enter an online game which involves passing a ball between themselves and two virtual confederates with whom the participant believes are other players. In the inclusion condition, the ball was passed between three players evenly, where the participant received the ball 33% of the time. In the exclusion condition, participants received the ball only 10% of the time. Each condition was approximately 3 min in duration. The task was generated using Empirisoft Cyberball 5.
Before arrival, participants were told to withhold from consuming stimulants (e.g. caffeine) or depressants (e.g. alcohol) for 2 days before the session. On arrival, participants gave informed consent and had their weight and height recorded. Participants were then questioned about their recent use of stimulants and depressants. No participants reported ingesting stimulants or depressants for 2 days for drugs and alcohol and 12 h for caffeine before the experimental session. Participants also had a brief history taken to determine whether they had any health condition that could impede data interpretation. Participants who had preexisting health conditions were not included in the study (n = 1). Eligible participants then completed an online survey containing the psychological variables. Next, participants were seated comfortably in a chair to ensure an accurate acclimatization period was reached for baseline measurements. Participants were then instrumented with the finometer, respiratory belt, and the three-lead electrocardiogram. Each signal was manually inspected before recording, and the finometer was calibrated before the start of each recording against brachial blood pressure using an Omron sphygmometer. Participants were asked to relax and refrain from moving or speaking for 10 min to ascertain baseline measurement. To ensure comfort and lack of movement, a pillow functioning as an armrest was placed on the participant's lap.
Once the baseline measurements were recorded, participants completed the first 3-min condition of the social stress task, the inclusion condition. This was followed by a 10-min rest period. Following the rest period, participants completed the second 3-min condition of the social stress task, the exclusion condition. We used a fixed presentation sequence to ensure participants felt the effects of social exclusion more intensely, that is, by presenting the inclusion condition first and the exclusion condition second participants are more likely to recognize that they have been excluded. Finally, participants completed a final recovery period of 5 min to ensure that responses returned to normal following the exclusion condition. After each Cyberball condition, participants completed a state affect questionnaire.
All statistical analyses were run using IBM Statistical Package for the Social Sciences version 25 (SPSS), SPSS, Armonk, New York, USA. Preliminary data analyses were checked to ensure that all data adhered to rules of normality. Approximately 20% of the psychophysiology data was missing and was imputed using maximum likelihood estimation within SPSS software including 5000 iterations of the dataset. Cardiovascular reactivity was assessed from the differences in systolic and diastolic blood pressure, heart rate, and respiratory rate during the Cyberball task's exclusion and inclusion conditions compared against their own baseline measurements. Age, gender, and body mass index were added as covariates for all analyses. Paired samples t-tests were conducted to test the effects between the active and rest conditions. Bonferroni corrections were used to adjust for multiple comparisons, and in cases where Levene's test of equal variance is not assumed, Welch's t-test was conducted. Correlation analyses were conducted to determine whether relationships existed between the psychological constructs and the cardiovascular indices.
To investigate the possible influence of perceived social isolation, social anxiety and depression on cardiovascular reactivity, we conducted a post-hoc analysis where we separated the group into “responders” and “non-responder”. Responders and nonresponders were defined a priori by scoring above or below the median difference in systolic blood pressure from exclusion to the rest period immediately preceding the Cyberball condition. We decided on systolic blood pressure for this analysis because of its consistent implication in cardiovascular stress responses.
| Results|| |
Positive affect scores significantly reduced between the inclusion (M = 10.60, SD = 4.09) and exclusion conditions (M = 9.65, SD = 3.82), t (62) =2.25, P < 0.028, Cohen's d = 0.27. Negative affect scores did not change between the inclusion (M = 6.19, SD = 1.94) and exclusion conditions (M = 6.02, SD = 1.69), t (62) =0.74, P = 0.464, Cohen's d = 0.10. The reduction in positive affect suggests the task was effective at inducing psychosocial stress.
Paired samples t-tests revealed participants' heart rate significantly increased during the inclusion and exclusion conditions [Table 2] and [Figure 1]. This was similarly the case for respiratory rate where there were significant increases in respiratory rate for the inclusion and exclusion conditions. There was no significant heart rate difference between the exclusion and inclusion conditions but there was for respiratory rate. Participants' systolic and diastolic blood pressure remained unchanged during the inclusion condition but significantly increased during the exclusion condition for systolic blood pressure.
|Figure 1: Psychophysiological responses across different experimental phase. (a) Represents heart rate, (b) represents systolic blood pressure, (c) represents diastolic blood pressure, and (d) represents respiratory rate. *P < 0.05, **P < 0.01, ***P < 0.001|
Click here to view
|Table 2: Means, standard deviations, and inferential statistics for each comparison for each physiological measure|
Click here to view
Responders and nonresponders
As seen in [Table 3], a significant difference was observed between responders (M = 18.31, SD = 12.82) and nonresponders (M = 12.75, SD = 7.44) on the depression scale, t (49.78) =2.12, P < 0.039, Cohen's d = 0.53. There were no significant differences between responders and nonresponders for perceived social isolation and social anxiety.
|Table 3: Means and standard deviations for responders and nonresponders across three psychological variables of interest|
Click here to view
We found evidence for blunted cardiovascular responses related to social anxiety and depression symptomatology. There was a significant relationship between social anxiety and systolic blood pressure for the social exclusion condition, such that higher scores on the social anxiety measure were associated with lower systolic blood pressure during the social stress condition. Social anxiety was also significantly and positively associated with heart rate during social exclusion, such that higher social anxiety scores were associated with higher heart rate in the exclusion condition. The same result was found for depression whereby higher depression scores were significantly correlated with lower systolic blood pressure scores in the social stress condition. For the remainder of the significant effects, see [Table 4].
| Discussion|| |
The aim of the study was to determine whether brief social stress through social exclusion would be associated with alterations in cardiovascular reactivity. To test this, we used an ostensible ball-throwing game, the Cyberball game, to induce feelings of social exclusion while participants had their heart rate, blood pressure, and respiratory rate continuously measured. We found psychological and physiological evidence that a brief social stressor can influence cardiovascular reactivity in a similar way to other known laboratory stressors such as mental arithmetic tasks and the TSST.
To determine whether the Cyberball task was effective at inducing feelings of social exclusion in our sample, we expected that all participants would experience more negative affect and less positive affect after the exclusion condition compared with inclusion. While participants did report less positive affect following social exclusion, they reported no change in negative affect post exclusion. Although some studies have shown increases in negative affect,, it is not uncommon to see reductions in positive affect in the absence of changes to negative affect. Furthermore, heart rate and respiratory rate both increased during the active stages of the experiment (i.e. the inclusion and exclusion phases) compared with their corresponding rest periods. Methodologically, the duration of the ostracism task and the number of ball throws is appropriate for eliciting social exclusion. A recent meta-analysis revealed large effect-sizes for the Cyberball task eliciting feelings of social exclusion, and that this is similarly the case when inducing social exclusion in brief (<5 min) or standard (5–10 min) induction periods. We interpret these findings collectively as the task proving effective at inducing social stress through exclusion and that participants were engaged with the task, providing confidence that active conditions of the game had the potential to influence psychophysiology in general.
Given that the manipulation was successful, we expected that participants would experience an increase in blood pressure, heart rate, and respiratory rate when being socially excluded compared with included. In line with previous studies, systolic and diastolic blood pressure increased significantly after being exposed to social exclusion. This shows that even seemingly small amounts of social stress may negatively impact physiology. Currently, it is unclear how repeated increased blood pressure responses to social stress can chronically affect cardiovascular health, however, it is important to note that studies with a follow-up of >5 years tend to show a positive association between blood pressure hyperactivity to stress and future hypertension. Flaa et al. also noted that blood pressure, heart rate, and sympathetic nervous system reactivity during stress were better predictors of future blood pressure than resting levels.
We also expected that those who are more vulnerable to perceiving social environments as threatening (i.e. those who perceive themselves as socially isolated, socially anxious, or depressed) would have increased resting and reactive psychophysiology. We failed to show such an effect for depression, social anxiety, and perceived social isolation. Perceived social isolation has been associated with blood pressure responses across different populations, but other studies have failed to find any relationship. The differences observed between these studies may be due, in part, to the different types of stressors implemented. Alternatively, this may be because we primarily recruited healthy young people and the effects may be too nuanced, making it difficult to conclude perceived social isolation and cardiovascular reactivity. Regardless, we failed to find an effect of perceived social isolation on resting and reactive cardiovascular activity in the current study, suggesting social exclusion may not lead to loneliness momentarily.
There were no significant effects for resting physiology, but we did find that higher social anxiety and depression scores were associated with lower systolic blood pressure responses when the participant was socially rejected. Further, participants who were classified as responders reported lower depression scores than the non-responders, suggesting that more problematic levels of depression may have blunted physiological responses to social exclusion. Previous investigations have shown blunted stress responses in people with higher levels of social anxiety and depression. Indeed, people with higher depression symptomatology or major depressive disorder typically demonstrate flattened blood pressure responses to the exposure of performance-based (e.g. mental arithmetic tasks) and social-based (e.g. TSST) stressors., Thus, social stressors may attenuate blood pressure responses, particularly in the short period following social exclusion.
This study supports the utility of social exclusion as a brief social stressor, but there are some study limitations that need to be considered. First, while we did find that positive affect reduced after being excluded, we did not measure whether participants reported the Cyberball task to be socially relevant or stressful, nor did we measure whether participants explicitly felt included or excluded during the task. Therefore, we cannot fully determine whether the task invoked social stress. Extensions of this research should measure whether the participants reported feeling included and excluded to ensure participants felt stressed through social exclusion. Second, the study employed a single experimental laboratory design. This is problematic because we cannot draw conclusions about the continuation of this effect over time. For example, over time, does this effect become cumulative or do people habituate to relational victimization stress? Future investigations should determine the longevity of these effects and whether cardiovascular responses habituate to social stressors over time. Finally, we were unable to directly compare the effects observed here with that from the TSST, so our findings are limited in comparability. Future indications should directly compare social stress from the Cyberball task with social stress from the TSST.
| Conclusion|| |
In the current study, we presented findings showing that a short, 3-min, social stressor can increase cardiovascular reactivity. These findings provide additional insight into the social determinants of health. Lacking a secure social environment, or being excluded from a social environment, can impact largely on cardiovascular health, therefore it is pivotal to determine psychophysiological pathways that may underlie even the briefest disruptions to our social environment. While there is ample evidence for cardiovascular reactivity to mental arithmetic and the TSST, findings from the current study support the limited research on cardiovascular stress responses to being socially excluded.
Declaration of ethical approval and patient consent
The protocol of this study conformed to the Declaration of Helsinki for human experimentation. All participants provided written informed consent prior to participation. The experimental protocol was approved by the Swinburne University Human Ethics Committee (SUHREC # 2017/328) on 12th of February 2018.
Financial support and sponsorship
MHL, GWL and EAL were supported by Swinburne Research, Swinburne University of Technology. The study was supported in part by the State Government of Victoria's Operational Infrastructure Support Program, as well as an Early Career Research Support Fund allocated to RE.
Conflicts of interest
There are no conflicts of interest.
| References|| |
Hughes BM, Lü W, Howard S. Cardiovascular stress-response adaptation: Conceptual basis, empirical findings, and implications for disease processes. Int J Psychophysiol 2018;131:4-12.
Everson-Rose SA, Lewis TT. Psychosocial factors and cardiovascular diseases. Ann Rev Public Health 2005;26:469-500.
Specchia G, de Servi S, Falcone C, Gavazzi A, Angoli L, Bramucci E, et al
. Mental arithmetic stress testing in patients with coronary artery disease. Am Heart J 1984;108:56-63.
Hellhammer J, Schubert M. The physiological response to trier social stress test relates to subjective measures of stress during but not before or after the test. Psychoneuroendocrinology 2012;37:119-24.
Childs E, Vicini LM, De Wit H. Responses to the Trier Social Stress Test (TSST) in single versus grouped participants. Psychophysiology 2006;43:366-71.
Mestanik M, Mestanikova A, Visnovcova Z, Calkovska A, Tonhajzerova I. Cardiovascular sympathetic arousal in response to different mental stressors. Physiol Res 2015;64 Suppl 5:S585-94.
Rodríguez-Medina DA, Leija-Alva G, Domínguez-Trejo B, Hernández-Pozo MD, Cruz-Albarrán IA, Morales-Hernández LA, et al
. Effects of the trier social stress test on the distributions of IL-6 and MAP levels. Heliyon 2019;5:e01580.
Vella EJ, Friedman BH. Hostility and anger in: Cardiovascular reactivity and recovery to mental arithmetic stress. Int J Psychophysiol 2009;72:253-9.
Esler M, Jennings G, Lambert G. Measurement of overall and cardiac norepinephrine release into plasma during cognitive challenge. Psychoneuroendocrinology 1989;14:477-81.
Holterman LA, Murray-Close DK, Breslend NL. Relational victimization and depressive symptoms: The role of autonomic nervous system reactivity in emerging adults. Int J Psychophysiol 2016;110:119-27.
Baumeister RF, Tice DM. Point-counterpoints: Anxiety and social exclusion. J Soc Clin Psychol 1990;9:165-95.
Zwolinski J. Psychological and neuroendocrine reactivity to ostracism. Aggress Behav 2012;38:108-25.
Bass EC, Stednitz SJ, Simonson K, Shen T, Gahtan E. Physiological stress reactivity and empathy following social exclusion: A test of the defensive emotional analgesia hypothesis. Soc Neurosci 2014;9:504-13.
Williams KD, Cheung CK, Choi W. Cyberostracism: Effects of being ignored over the Internet. J Pers Soc Psychol 2000;79:748-62.
Hartgerink CH, van Beest I, Wicherts JM, Williams KD. The ordinal effects of ostracism: A meta-analysis of 120 Cyberball studies. PLoS One 2015;10:e0127002.
Iffland B, Sansen LM, Catani C, Neuner F. Rapid heartbeat, but dry palms: Reactions of heart rate and skin conductance levels to social rejection. Front Psychol 2014;5:956.
Iffland B, Sansen LM, Catani C, Neuner F. The trauma of peer abuse: Effects of relational peer victimization and social anxiety disorder on physiological and affective reactions to social exclusion. Front Psychiatry 2014;5:26.
Williamson TJ, Thomas KS, Eisenberger NI, Stanton AL. Effects of social exclusion on cardiovascular and affective reactivity to a socially evaluative stressor. Int J Behav Med 2018;25:410-20.
Nezlek JB, Imbrie M, Shean GD. Depression and everyday social interaction. J Pers Soc Psychol 1994;67:1101-11.
Torgrud LJ, Walker JR, Murray L, Cox BJ, Chartier M, Kjernisted KD. Deficits in perceived social support associated with generalized social phobia. Cogn Behav Ther 2004;33:87-96.
Perlman D, Peplau LA. Toward a social psychology of loneliness. Pers Relationsh 1981;3:31-56.
Lim MH, Eres R, Vasan S. Understanding loneliness in the twenty-first century: An update on correlates, risk factors, and potential solutions. Soc Psychiatry Psychiatr Epidemiol 2020;55:793-810.
Cacioppo JT, Ernst JM, Burleson MH, McClintock MK, Malarkey WB, Hawkley LC, et al
. Lonely traits and concomitant physiological processes: The MacArthur social neuroscience studies. Int J Psychophysiol 2000;35:143-54.
Ong AD, Rothstein JD, Uchino BN. Loneliness accentuates age differences in cardiovascular responses to social evaluative threat. Psychol Aging 2012;27:190-8.
Cacioppo JT, Hawkley LC, Crawford LE, Ernst JM, Burleson MH, Kowalewski RB, et al
. Loneliness and health: potential mechanisms. Psychosom Med 2002;64:407-17.
Nausheen B, Gidron Y, Gregg A, Tissarchondou HS, Peveler R. Loneliness, social support and cardiovascular reactivity to laboratory stress. Stress 2007;10:37-44.
Brown EG, Gallagher S, Creaven AM. Loneliness and acute stress reactivity: A systematic review of psychophysiological studies. Psychophysiology 2018;55:e13031.
Brindle RC, Ginty AT, Conklin SM. Is the association between depression and blunted cardiovascular stress reactions mediated by perceptions of stress? Int J Psychophysiol 2013;90:66-72.
Russell DW. UCLA loneliness scale (Version 3): Reliability, validity, and factor structure. J Pers Assess 1996;66:20-40.
Radloff LS. The CES-D scale: A self-report depression scale for research in the general population. Appl Psychol Meas 1977;1:385-401.
Mattick RP, Clarke JC. Development and validation of measures of social phobia scrutiny fear and social interaction anxiety. Behav Res Ther 1998;36:455-70.
Rodebaugh TL, Heimberg RG, Brown PJ, Fernandez KC, Blanco C, Schneier FR, et al
. More reasons to be straightforward: Findings and norms for two scales relevant to social anxiety. J Anxiety Disord 2011;25:623-30.
Watson D, Clark LA, Tellegen A. Development and validation of brief measures of positive and negative affect: The PANAS scales. J Pers Soc Psychol 1988;54:1063-70.
Lambert E, Phillips S, Tursunalieva A, Eikelis N, Sari C, Dixon J, et al
. Inverse association between sympathetic nervous system activity and bone mass in middle aged overweight individuals. Bone 2018;111:123-8.
Sleegers WW, Proulx T, van Beest I. The social pain of Cyberball: Decreased pupillary reactivity to exclusion cues. J Exp Soc Psychol 2017;69:187-200.
Helpman L, Penso J, Zagoory-Sharon O, Feldman R, Gilboa-Schechtman E. Endocrine and emotional response to exclusion among women and men; cortisol, salivary alpha amylase, and mood. Anxiety Stress Coping 2017;30:253-63.
Zhang Q, Li X, Wang K, Zhou X, Dong Y, Zhang L, et al
. Dull to social acceptance rather than sensitivity to social ostracism in interpersonal interaction for depression: Behavioral and electrophysiological evidence from cyberball tasks. Front Hum Neurosci 2017;11:162.
Schwerdtfeger A, Rosenkaimer AK. Depressive symptoms and attenuated physiological reactivity to laboratory stressors. Biol Psychol 2011;87:430-8.
Carroll D, Smith GD, Shipley MJ, Steptoe A, Brunner EJ, Marmot MG. Blood pressure reactions to acute psychological stress and future blood pressure status: A 10-year follow-up of men in the Whitehall II study. Psychosom Med 2001;63:737-43.
Flaa A, Eide IK, Kjeldsen SE, Rostrup M. Sympathoadrenal stress reactivity is a predictor of future blood pressure. Hypertension 2008;52:336-41.
Gramer M, Saria K. Effects of social anxiety and evaluative threat on cardiovascular responses to active performance situations. Biol Psychol 2007;74:67-74.
[Table 1], [Table 2], [Table 3], [Table 4]