Negative affectivity and bodily sensations induced by 5.5% CO2enriched air inhalation: Is there a bias to interpret bodily sensations negatively in persons with negative affect?

Categorical interoception: the role of disease context and individual differences in habitual symptom reporting

OBJECTIVE

Symptom reports correspond less to physiological dysfunction in persons with high levels of symptoms in daily life and in patients with functional somatic symptoms, suggesting poor symptom perception. In this study, we investigated whether interoception was impacted by the meaning of the context and by habitual symptom reporting.

METHODS

Eight inspiratory resistances that were equidistant in intensity were administered to healthy women (N = 124) varying in habitual symptom reporting. One group was asked to categorise them as benign sensations vs. as bodily symptoms that could suggest a disease (disease context group). Another group was asked to categorise them as low- vs. high-intensity sensations (neutral context group).

MAIN OUTCOME

Perceived differences in intensity within- vs. between-category and unpleasantness, categorisation threshold, and the reliability of categorising each stimulus were examined in relation to context (disease, neutral) and symptom reporting levels in daily life.

RESULTS

Context (neutral vs. disease) impacted intensity and unpleasantness perception. Processing of respiratory interoceptive stimulation was more detailed, elaborate, and cautious when categorising stimuli as signalling health or disease vs. as low- or high-intensity. Individual differences in habitual symptoms had no effect.

CONCLUSION

The pattern of results suggests that these categorisation effects indicate flexible, context-sensitive interoceptive processing, which may characterise healthy individuals.

Spatiotemporal Dynamics of Stress-Induced Network Reconfigurations Reflect Negative Affectivity

BACKGROUND

Maladaptive stress responses are important risk factors in the etiology of mood and anxiety disorders, but exact pathomechanisms remain to be understood. Mapping individual differences of acute stress-induced neurophysiological changes, especially on the level of neural activation and functional connectivity (FC), could provide important insights in how variation in the individual stress response is linked to disease risk.

METHODS

Using an established psychosocial stress task flanked by two resting states, we measured subjective, physiological, and brain responses to acute stress and recovery in 217 participants with and without mood and anxiety disorders. To estimate blockwise changes in stress-induced activation and FC, we used hierarchical mixed-effects models based on denoised time series within predefined stress-related regions. We predicted inter- and intraindividual differences in stress phases (anticipation vs. stress vs. recovery) and transdiagnostic dimensions of stress reactivity using elastic net and support vector machines.

RESULTS

We identified four subnetworks showing distinct changes in FC over time. FC but not activation trajectories predicted the stress phase (accuracy = 70%, p_perm < .001) and increases in heart rate (R² = 0.075, p_perm < .001). Critically, individual spatiotemporal trajectories of changes across networks also predicted negative affectivity (ΔR² = 0.075, p_perm = .030) but not the presence or absence of a mood and anxiety disorder.

CONCLUSIONS

Spatiotemporal dynamics of brain network reconfiguration induced by stress reflect individual differences in the psychopathology dimension of negative affectivity. These results support the idea that vulnerability for mood and anxiety disorders can be conceptualized best at the level of network dynamics, which may pave the way for improved prediction of individual risk.

An Anti-hyperventilation Instruction Decreases the Drop in End-tidal CO2 and Symptoms of Hyperventilation During Breathing at 0.1 Hz

Breathing at a frequency of around 0.1 Hz is widely used in basic research and in applied psychophysiology because it strongly increases fluctuations in the cardiovascular system and affects psychological functioning. Volitional control of breathing often leads to hyperventilation among untrained individuals, which may produce aversive symptoms and alter the psychological and physiological effects of the paced breathing. The present study investigated the effectiveness of a brief anti-hyperventilation instruction during paced breathing at a frequency of 0.1 Hz. Forty-six participants were randomly assigned to one of two groups: a group given an anti-hyperventilation instruction and a control group without such an instruction. The instruction asked participants to avoid excessively deep breathing and to breathe shallowly and naturally. Participants performed the breathing task for 10 min. Hyperventilation was measured by partial pressure of end-tidal CO₂ (PetCO₂); furthermore, symptoms of hyperventilation, feeling of air hunger, task difficulty, and affective state were measured by self-report. The results showed that paced breathing without instruction decreased PetCO₂ by 5.21 mmHg and that the use of the anti-hyperventilation instruction reduced the drop in PetCO₂ to 2.7 mmHg. Symptoms of hyperventilation were lower in the group with the anti-hyperventilation instruction. Neither the feeling of air hunger nor task difficulty were affected by the instruction. There were no significant effects of the instruction on affective state. The present study indicates that a brief anti-hyperventilation instruction may be used to decrease drop in PetCO₂ and symptoms of hyperventilation during breathing at 0.1 Hz and that the instruction is well tolerated.

Cyberchondriasis

Abstract. Studies show a rising trend that individuals who worry about their health regularly search the internet. Recently, potentially negative effects of doing so have been highlighted. Illness anxiety and negative affectivity may influence these effects. We tested if searching the internet about a personal symptom leads to increased health concerns and if these traits have an impact. Data from 79 students were collected. Participants were asked to name and evaluate a symptom of personal concern and to research that symptom using the Internet for 5 min. Searching the internet resulted in a significant increase in health concerns and this was significantly moderated by negative affectivity but not by illness anxiety. A replication of these findings, possibly with an older sample scoring higher on illness anxiety will help to better understand the relations described above, and to point consumers and health professionals into the right direction regarding media usage.

Microaggression Research and Application: Clarifications, Corrections, and Common Ground

In this issue, Williams (pp. 3-26) responds to my 2017 critique in this journal of the scientific status of the microaggression research program (MRP). In some cases, she presents helpful data that partially address several of my recommendations for enhancing the MRP's rigor. Nevertheless, because she appears to misconstrue many of my arguments regarding the MRP, many of her rebuttals are not relevant to my criticisms. Furthermore, her assertions notwithstanding, Williams does not effectively address my concerns regarding the (a) excessively fuzzy boundaries of the microaggression construct, (b) psychometric hazards of relying exclusively on subjective reports when detecting microaggressions, and (c) hypothesized causal impact of microaggressions on mental health. In other cases, Williams appears to draw causal inferences from correlational data and conflate within-group with between-group differences. Although several of Williams's recommendations for MRP research are worth considering, I contend that some others are unlikely to be conducive to a scientific approach to microaggressions. The MRP remains a promising but provisional research program that would benefit from greater openness to outside criticism. I conclude with a discussion of areas of potential common ground in microaggression research and application.

Repeated Interoceptive Exposure in Individuals With High and Low Anxiety Sensitivity

Interoceptive exposure is one component in cognitive behavioral therapy of panic disorder. The present investigation addressed changes in defensive mobilization during repeated interoceptive exposure using a standardized hyperventilation procedure. 26 high and 22 low anxiety sensitive persons (ASI, Peterson & Reiss, 1992) went through two guided hyperventilation and normoventilation procedures, spaced one week apart. Breathing parameters, startle response magnitudes and symptom reports were measured. All participants successfully adhered to the guided breathing procedures. Both groups comparably reported more symptoms during hyperventilation than normoventilation in both sessions. Only high-AS participants displayed potentiated startle magnitudes after the first hyperventilation vs. normoventilation. One week later, when the hyperventilation exercise was repeated, this potentiation was no longer present. Thus, high and low-AS groups no longer differed in their defensive mobilization to symptom provocation. Furthermore, the number of reported baseline symptoms also decreased from session one to session two in the high-AS group. While high-AS reported increased baseline anxiety symptoms in session 1, groups did not differ in session 2. Results indicate a reduction of defensive mobilization during repeated interoceptive exposure.

Symptom onset and the socially sanctioned pathway: the example of diet

Theories of symptom perception do not explain symptom onset, nor why symptoms vary according to culture and time. This article attempts to explain cultural, temporal and individual variation in symptoms, and presents a new three-stage model of symptom onset. First, it is argued that tensions relating to issues of conflict and control arise as an individual interfaces with their social world and that this requires communication. Second, it is suggested that symptoms are embedded with culturally specific meanings which offer up a socially sanctioned pathway as a forum for communication. Third, if this pathway is appraised as personally relevant, the symptoms offered by the pathway will be adopted as the forum for communication. The resulting symptoms are therefore both culturally and personally meaningful. This model is derived from an analysis of the literature on diet, but is also offered as a means to understand the onset of other common symptoms.

Short report: Functional somatic symptoms are associated with perfectionism in adolescents

OBJECTIVE

The aim of this study is to investigate the influence of perfectionism on functional somatic symptoms (FSSs) in adolescents. It was hypothesized that perfectionism predicts higher levels of FSSs cross-sectionally and longitudinally, and that anxiety and depression mediate this relationship.

DESIGN

This prospective population-based study was part of the Dutch Tracking Adolescents' Individual Lives Survey (N=2230; 50.8% girls). Data from 1878 participants attending the third (T3) or fourth (T4) assessment wave were used (mean age T3: 16.2 (SD:0.7); mean age T4: 19.0 (SD:0.6)). Multiple regression and mediation analyses were performed in Mplus.

MAIN OUTCOME MEASURES

FSSs, perfectionism (i.e. the feeling one has to be perfect), anxiety and depression were assessed with the Youth Self-Report at the third and fourth wave.

RESULTS

Perfectionism was associated with a higher level of FSSs in adolescents, both cross-sectionally (B=0.11, 95%-CI: 0.08-0.14) and longitudinally (B=0.05, 95%-CI: 0.02-0.08). There was a small indirect effect of perfectionism on FSSs trough anxiety and depression (B=0.02, 95%-CI: 0.003-0.03, k(2)=0.02).

CONCLUSION

The results suggest that perfectionism predicts the course of FSSs with a small indirect effect of perfectionism on FSSs trough anxiety and depression. Further research is needed to clarify which aspects of perfectionism are particularly responsible for this effect.

Dyspnea related to reversibly-binding P2Y12 inhibitors: A review of the pathophysiology, clinical presentation and diagnostics

Dyspnea is a common symptom physiologically associated with strenuous exercise and pathologically reflecting well-known diseases and conditions that are predominantly pulmonary, cardiovascular, and weight-related in origin. Dyspnea improves with appropriate measures that enhance physical performance and treatment of the underlying diseases. Dyspnea is less commonly triggered by other causes such as the environment (e.g., ozone), drugs, and others, some of which do not seem to affect bronchopulmonary function as evidenced by normal results of comprehensive pulmonary function testing. In cardiovascular medicine, dyspnea has recently attracted attention because it has been reported that this symptom occurs more frequently with the administration of the new oral reversibly-binding platelet P2Y12 receptor inhibitors ticagrelor [1-6], cangrelor [7-10], and elinogrel [11]. This paper succinctly addresses the current understanding of the pathophysiology, clinical presentation, and diagnostics of dyspnea, associated either with bronchopulmonary function impairment, as triggered mainly by pulmonary and cardiovascular diseases, or without bronchopulmonary function impairment, as induced by endogenous or external compounds such as drugs in order to provide a context for understanding, recognizing and managing P2Y12 inhibitor-induced dyspnea.

Anxiety and depression are risk factors rather than consequences of functional somatic symptoms in a general population of adolescents: the TRAILS study

BACKGROUND

It is well known that functional somatic symptoms (FSS) are associated with anxiety and depression. However, evidence is lacking about how they are related to FSS. The aim of this study was to clarify these relationships and examine whether anxiety and depression are distinctly related to FSS. We hypothesized that anxiety contributes to the development of FSS and that depression is a consequence of FSS.

METHODS

FSS, anxiety, and depression were measured in adolescents (N = 2230, 51% women) by subscales of the Youth Self-Report during three assessment waves (adolescents successively aged: 10-12, 12-14, and 14-17) and by corresponding subscales of the Child Behavior Checklist. Using structural equation models, we combined trait and state models of FSS with those of anxiety and depression, respectively. We identified which relationships (contemporaneous and two-year lagged) significantly connected the states of FSS with the states of anxiety and depression.

RESULTS

Trait variables were all highly interrelated (r = .54-.63). Contrary to our hypothesis, both state anxiety (beta = .35) and state depression (beta = .45) had a strong contemporaneous effect on state FSS. In turn, state FSS had a weak two-year lagged effect on state anxiety (beta = .11) and an even weaker effect on state depression (beta = .06).

CONCLUSIONS

While the effect of anxiety and depression on FSS is strong and immediate, FSS exert a weaker and delayed influence on anxiety and depression. Further research should be done to detect the exact ways in which anxiety and depression lead to FSS, and FSS lead to anxiety and depression.

Inaccurate perception of asthma symptoms: a cognitive-affective framework and implications for asthma treatment

Inaccurate perception of respiratory symptoms is often found in asthma patients. Typically, patients who inaccurately perceive asthma symptoms are divided into underperceivers and overperceivers. In this paper we point out that this division is problematic. We argue that little evidence exists for a trait-like stability of under- and overperception and that accuracy of respiratory symptom perception is highly variable within persons and strongly influenced by contextual information. Particularly, expectancy and affective cues appear to have a powerful influence on symptom accuracy. Based on these findings and incorporating recent work on associative learning, attention and mental representations in anxiety and symptom perception, we propose a cognitive-affective model of symptom perception in asthma. The model can act as a framework to understand both normal perception as well as under- and overperception of asthma symptoms and can guide the development of affect-related interventions to improve perceptual accuracy, asthma control and quality of life in asthma patients.

Negative affect and chemical intolerance as risk factors for building-related symptoms: a controlled exposure study

OBJECTIVE

To assess whether differences in negative affect (NA) and chemical intolerance (CI) affect responses to chemical mixtures and stress in a controlled experimental model.

METHODS

Participants were 130 nonsmoking, healthy women, recruited from a university community. Participants completed the Positive and Negative Affect Scale and the Chemical Odor Intolerance Index. In separate sessions 1 week apart, they were exposed to volatile organic compounds (VOCs), VOCs with ozone (VOCs+O3), and ambient or filtered air with a 1-minute spike of VOCs (masked clean air). During each session, half of the participants performed a videotaped speech stressor and half performed simple arithmetic. Before, during, and after each session, salivary cortisol samples were collected, and subjects completed neurobehavioral tests and used a ratio scale to rate physical, cognitive, and anxiety symptoms.

RESULTS

Relative to low NA or low CI, neither the high NA nor the high CI groups reported significantly more symptoms in response to any exposure condition. High NA subjects reported more anxiety symptoms in response to the speech stressor but did not have higher cortisol than low NA subjects. High NA subjects, however, were more distressed by the experimental conditions than were low NA subjects. Low NA subjects reported more severe anxiety in the VOCs+O3 with psychological stress condition.

CONCLUSIONS

Subjects high in NA were more anxious after a stressor but were not more physically symptomatic in response to increasing chemical exposures. A disposition toward high or low CI did not result in a differential symptomatic response to controlled chemical exposures.

Emotional reactivity and the overreport of somatic symptoms: somatic sensitivity or negative reporting style?

OBJECTIVE

The purpose of this study is to examine the role of emotional reactivity (ER) in symptom reporting and conceptualize somatizing processes as a signal detection task. Emotional reactivity has been theorized to influence symptom reporting through somatic sensitivity as well as via a negative reporting style. We assess the degree to which these two competing theories about the role of ER are accurate within the signal detection framework.

METHODS

We used a multimethod approach that included using both static and prospective self-reports as well as a signal detection task.

RESULTS

Results suggest that ER exerts its influence on somatization tendencies via a negatively biased reporting style and is not mediated by somatic sensitivity as suggested by the somatosensory amplification and the symptom perception hypothesis.

CONCLUSION

Emotional reactivity has yet to be associated with objective measures of somatic sensitivity. Until such an association is found, it is likely that ER influences symptom reports via negatively biased reporting.

Can subjective asthma symptoms be learned?

OBJECTIVE

We investigated whether perception of subjective asthma symptoms can be brought under control of biomedically irrelevant cues in the environment, i.e., whether subjective asthma symptoms can be learned in response to harmless stimuli.

METHODS

Twenty patients with asthma and 20 healthy participants were presented with two placebo-inhalers presented as new chemicals for diagnosing asthma. One inhaler was coupled three times with rebreathing 5% CO2 in oxygen, the other inhaler was coupled three times with rebreathing oxygen. In the subsequent test phase, both inhalers were coupled once with oxygen. We assessed airway resistance and subjective symptoms throughout the study.

RESULTS

Both groups expected and reported more symptoms with the inhaler that was previously associated with the CO2 trials compared with trials with the inhaler that was used on trials without CO2 without concomitant effects on respiratory resistance. The learning effects were most pronounced in a subgroup of patients reporting symptoms of hyperventilation during asthma exacerbations in daily life.

CONCLUSIONS

Subjective respiratory symptoms can be learned in response to harmless stimuli and a substantial proportion of patients with asthma might be especially vulnerable to this phenomenon. Because asthma patients rely mainly on perceived symptoms for their medication use, it is likely that they will take reliever medication based on expected symptoms instead of real exacerbations of respiratory dysfunction.

Negative affectivity and the influence of suggestion on asthma symptoms

OBJECTIVE

To investigate the effect of suggestion on subjective and objective asthma symptoms as a function of negative affectivity of the patients.

METHODS

Asthmatics (n=32) took puffs from three separate placebo inhalers, being described as an inert (practice) substance, a bronchoconstrictor, and a bronchodilator. Negative affectivity, social desirability, probability of medication-intake, intensity of asthma symptoms and total respiratory resistance were measured at onset. The latter three measures were repeated after each trial. Heart rate, end tidal PCO(2), and breathing behaviour were measured during each trial.

RESULTS

Asthmatics with high negative affectivity had overall more intense asthma symptoms. They also reported more airway obstruction after suggested bronchoconstriction and less after suggested bronchodilation, whereas persons with low negative affectivity did not show such variation. These effects were unrelated to social desirability. Respiratory symptoms correlated with the odds of medication intake. Neither negative affectivity nor suggestion influenced lung function and only breathing parameters under voluntary control changed as a function of suggestion.

CONCLUSION

Self-reported symptoms of asthmatics with high negative affectivity are more influenced by suggestion than those of patients with low negative affectivity.

Resting end-tidal CO2 and negative affectivity

OBJECTIVE

Dhokalia, Parsons, and Anderson (Psychosom Med 1998;60:33-37) found a positive correlation between a trait measure of negative affectivity (NA; neuroticism) and resting end-tidal fractional concentration of CO2 (FetCO2) (fractional-concentration of end-tidal carbon dioxide) in a nonclinical sample. This contrasts sharply with studies reporting a negative association of FetCO2 with state measures of NA and with studies reporting no or a negative relationship between FetCO2 and trait NA. In two studies we aimed to clarify this paradox.

MATERIALS AND METHODS

In the first study, 110 participants (83 women) completed the PANAS and a Checklist for Psychosomatic Symptoms in daily life. FetCO2 was measured noninvasively during 5 minutes via a nose cannula connected to a capnograph. In the second study, FetCO2 of high (N= 20, 10 men) and low (N= 20, 10 men) NA participants was sampled once with a nasal cannula and once while breathing through a mouthpiece for 6 minutes each during rest, completion of the NEO-PI-R questionnaire, and completion of a verbal knowledge test.

RESULTS

The first study found no association between trait NA and resting FetCO2 after partialling out the effects of gender, menstrual phase, and use of oral contraceptives. The second study showed that FetCO2 increased significantly in the high NA group only when the particpants filled out the questionnaires, regardless of its type.

CONCLUSIONS

Overall, no association between dispositional NA and cross-situational FetCO2 was observed. Apparently inconsistent findings may be caused by lack of control for hormonal status and mental load during testing.

Effects of distraction on treadmill running time in severely obese children and adolescents

OBJECTIVE

(1) To examine the effects of attentional distraction on running time in an incremental treadmill test in obese youngsters; (2) to investigate whether distraction works at the same extent at the beginning and at the end of residential treatment; and (3) to explore the underlying mechanisms of the possible distraction effects.

METHODS

Thirty severely obese youngsters (10 boys, 20 girls, age range 9-17) who were following a 10 month residential treatment, performed a treadmill test until exhaustion in four different sessions using a within subjects design. The two sessions at the beginning of the treatment and the two sessions at the end the treatment were counterbalanced, one with attentional distraction (music) and one without distraction.

RESULTS

Obese youngsters ran significantly longer during distraction. This distraction effect seemed to be larger at the beginning compared to at the end of obesity treatment. The absence of differences between the condition with music and the condition without music on perceived bodily symptoms is in line with the idea that it took longer to perceive sufficient bodily sensations to decide to stop the treadmill test in the distraction condition. This interpretation is further corroborated by the physiological data indicating a superior peak performance in the condition with distraction.

CONCLUSIONS

Attentional distraction has a positive effect on perseverance in obese youngsters. Further research has to show the usefulness of attentional distraction as a technique to increase exercise adoption and adherence in obesity treatment.

Learning subjective health complaints

Symptom episodes often show a spatio-temporal structure, that is, they occur in a specific context for a certain duration. Repeated experiences may therefore be construed as associative learning trials, in which context elements are turned into predictive cues, triggering anticipatory processes conducive to subjective health complaints. A series of experiments, using inhalations of air enriched with CO2 and external (odors) or internal (mental images) stimuli as cues, is discussed to show that subjective health complaints may occur upon presenting the cue alone. Learned symptoms may be unrelated to bodily responses and easily generalize to new related cues. Better learning occurs to cues with a negative affective valence and in participants scoring high for negative affectivity. Our findings are relevant to the understanding of medically unexplained ("functional") syndromes and the poor relationship between objective and subjective health indicators in general.

Generalization of acquired somatic symptoms in response to odors: a pavlovian perspective on multiple chemical sensitivity

OBJECTIVE

Somatic symptoms that occur in response to odors can be acquired in a pavlovian conditioning paradigm. The present study investigated 1) whether learned symptoms can generalize to new odors, 2) whether the generalization gradient is linked to the affective or irritant quality of the new odors, and 3) whether the delay between acquisition and testing modulates generalization.

METHODS

Conditional odor stimuli (CS) were (diluted) ammonia and niaouli. One odor was mixed with 7.4% CO2-enriched air (unconditional stimulus) during 2-minute breathing trials (CS+ trial), and the other odor was presented with air (CS- trial). Three CS+ and three CS- trials were conducted in a semirandomized order (acquisition phase). The test phase involved one CS+-only (CS+ without CO2) and one CS- test trial, followed by three trials using new odors (butyric acid, acetic acid, and citric aroma). Half of the subjects (N = 28) were tested immediately, and the other half were tested after 1 week. Ventilatory responses were measured during and somatic symptoms were measured after each trial.

RESULTS

Participants had more symptoms in response to CS+-only exposures, but only when ammonia was used as the CS+. Also, generalization occurred: More symptoms were reported in response to butyric and acetic acid than to citric aroma and only in participants who had been conditioned. Both the selective conditioning and the generalization effect were mediated by negative affectivity of the participants. The delay between the acquisition and test phases had no effect.

CONCLUSIONS

Symptoms that occur in response to odorous substances can be learned and generalize to new substances, especially in persons with high negative affectivity. The findings further support the plausibility of a pavlovian perspective of multiple chemical sensitivity.