The impact of emotions on symptom perception in patients with asthma and healthy controls.

Accurate perception of respiratory symptoms is highly important for course and treatment of asthma. Recent findings suggest that emotions can greatly impact respiratory symptom perception. This study compared the impact of emotions on respiratory symptom perception between patients with asthma and matched healthy controls. Pleasant and unpleasant emotional states were elicited by viewing emotional picture series while symptom reports and respiratory parameters were measured. Greater symptom report was observed for the unpleasant compared to the pleasant emotional state that was not related to respiratory parameters. Notably, this effect was comparable between patients with asthma and healthy controls. The present results suggest that the impact of emotions on respiratory symptom perception is a rather general phenomenon and not dependent upon previous experiences with asthma symptoms.

Looking at allergens increases symptom report in patients with allergic asthma.

OBJECTIVE: Accurate symptom perception is highly important for self-management and clinical treatment of asthma. Recent findings suggest that psychological factors can greatly impact asthma symptom perception. This study examined whether looking at allergens would lead to changes in perceived asthma symptoms. METHODS: Allergic asthma patients and healthy controls viewed picture series containing either allergens or neutral material. Symptom reports and respiratory parameters were measured. RESULTS: The present results demonstrate that looking at pictures with allergens increases subjective symptom reports in patients with allergic asthma in the absence of changes in objective respiratory parameters, but not in healthy controls. CONCLUSIONS: The results are suggestive of preceding learning processes during which patients have learned the association between visual representations of allergens and symptom-inducing effects of real contact with these allergens. This impacts asthma symptom perception without changes in respiratory status and might influence treatment decisions.

Unconditioned and conditioned muscular responses in patients with chronic back pain and chronic tension-type headaches and in healthy controls.

Muscular tension is assigned an important role in the development and maintenance of chronic pain syndromes. It is seen as a psychophysiological correlate of learned fear and avoidance behavior. Basic theoretical models emphasize classical conditioning of muscular responses as a mechanism of pain chronification. However, the empirical basis for this field is very small. Our aim was to investigate muscular factors in relation to unconditioned and conditioned pain stimuli. An experimental study was conducted using a differential classical conditioning paradigm with 18 patients with chronic back pain (BP) and tension-type headache (TTH), and 18 healthy controls (HC). A high-pitched sound served as the CS+, paired with an intracutaneous electric pain stimulus (US), while a neutral sound was used as the CS-. Simultaneously, integrated surface electromyograms (iEMGs) were recorded for seven muscle sites. Our hypothesis was that the pain patients would demonstrate enhanced conditionability. Baseline values between patients (TTH, BP) and HC showed no significant differences. Although the perception and pain thresholds were balanced, both patient groups revealed a higher number of significant muscular responses to the pain stimulus (UR) than the HC. All participants showed significant conditioned muscular responses, however, the patients displayed a higher number than the healthy controls. Furthermore a significant relation was found between muscular responses and the experience of pain 1day after the experiment. Muscular responses can be learned via classical conditioning. TTH and BP patients revealed a higher number of unconditioned and conditioned responses.

Airway response to emotional stimuli in asthma: the role of the cholinergic pathway.

In asthma, airways constrict in response to emotion and stress, but underlying mechanisms, potential extrathoracic contributions, and associations with airway pathophysiology have not been elucidated. We therefore investigated the role of the cholinergic pathway in emotion-induced airway responses in patients with asthma and the association of these responses with airway pathophysiology. Patients with asthma (n=54) and healthy participants (n=25) received either 40 microg ipratropium bromide or a placebo in a double-blind double-dummy cross-over design in two laboratory sessions with experimental emotion induction. Stimuli were preevaluated films and pictures of pleasant, unpleasant, and neutral quality. Respiratory resistance and reactance at 5 and 20 Hz were measured continuously before and during presentations, together with respiration by impedance plethysmography and end-tidal PCO2 by capnometry. In addition, measures of airway inflammation (fraction of exhaled nitric oxide), airway hyperreactivity (methacholine challenge), and reversibility of obstruction were obtained. Respiratory resistance at 5 and 20 Hz increased during unpleasant stimuli in asthma patients. This response was blocked by ipratropium bromide and was not substantially associated with asthma severity, airway inflammation, hyperreactivity and reversibility, or pattern of ventilation and PCO2. Under the placebo condition, changes in resistance during unpleasant films were positively correlated with patients' reports of psychological asthma triggers. In conclusion, airway constriction to unpleasant stimuli in asthma depends on an intact cholinergic pathway, is largely due to the central airways, and is not substantially associated with other indicators of airway pathology. Its link to the perceived psychological triggers in patients' daily lives suggests a physiological basis for emotion-induced asthma.

A short goal-pursuit intervention to improve physical capacity: a randomized clinical trial in chronic back pain patients.

The present study tested a short intervention using goal-pursuit strategies to increase physical capacity in pain patients. Sixty chronic back pain patients were randomly assigned to intervention or control conditions. Both groups followed a 3-week conventional back pain program at an outpatient back pain center. Instead of routine treatment, the intervention group received a one-hour intervention consisting of a combination of (a) a goal-setting strategy (i.e., mental contrasting, MC) aimed at commitment to improved physical capacity, (b) a short cognitive behavioral therapy-oriented problem-solving approach (CBT) to help patients overcome the obstacles associated with improving physical capacity, and (c) a goal-pursuit strategy, i.e., implementation intentions (II) aimed at performing physical exercise regularly. At two follow-ups (3 weeks after discharge and 3 months after returning home) the MCII-CBT group had increased its physical capacity significantly more than the control group as measured by both behavioral measures (ergometer, lifting) and subjective ratings. Findings are discussed with relation to the use of the intervention as a specific treatment to increase chronic pain patients' motivation to be physically active.

Emotional reactivity of the airways in asthma: consistency across emotion-induction techniques and emotional qualities.

Considerable individual differences exist in asthma patients' airway responses to emotional stimuli, but little is known about the generalization of such responses across situations or states of airways constriction. Fifty-four asthma patients and 25 healthy controls viewed in two separate sessions, films and blocks of pictures from each of three emotional qualities, pleasant, unpleasant, and neutral. At the beginning of each session, patients received a placebo or anti-cholinergic bronchodilator (ipratropium bromide), respectively, in a randomized double-blind design. Respiratory resistance, reactance and impedance were recorded throughout stimulus presentations with impulse oscillometry. Resistance increases showed a moderate degree of generalization across unpleasant films and pictures, unpleasant and pleasant pictures, as well as cholinergic blockade and placebo. Thus, the intensity of airway responses to unpleasant emotional stimuli is a moderately stable characteristic of asthma patients. In addition to the central airway, peripheral and extrathoracic airways may also contribute the consistency of such responses.

The impact of affective states on the perception of dyspnea in patients with chronic obstructive pulmonary disease.

Dyspnea is the cardinal symptom of chronic obstructive pulmonary disease (COPD). Affective states can profoundly impact upon the perception of dyspnea, but little is known about this relationship in patients with COPD. We, therefore, examined the impact of viewing positive versus negative affective picture series on perceived dyspnea during two cycle ergometer exercise tests (CEET) in 30 patients with COPD. Whereas cardiopulmonary measures indicated comparable exercise intensity during both CEETs, parallel viewing of negative affective pictures resulted in increased dyspnea ratings compared to positive affective pictures. Regression analyses showed that only during positive picture viewing increases in the affective unpleasantness of dyspnea, but not in the sensory intensity of dyspnea, during CEETs were predictive of greater dyspnea during everyday activities and reduced health-related quality of life. The results suggest that negative affective states increase perceived dyspnea in patients with COPD and underline the importance of targeting the affect-dyspnea-relationship in this patient group.

A MATLAB toolbox for correcting within-individual effects of respiration rate and tidal volume on respiratory sinus arrhythmia during variable breathing.

Respiratory sinus arrhythmia (RSA) is a common estimator of vagal outflow to the heart, dependent on parasympathetic activity. During variable breathing, both respiration rate and tidal volume contribute substantially to within-individual RSA variance. A respiratory control method allows for within-individual correction of the time-domain index of RSA. rsaToolbox is a set of MATLAB programs for scoring respiration-corrected RSA using measurements of cardiac interbeat intervals, respiratory-cycle times, and tidal volumes, recorded at different paced-breathing frequencies. The within-individual regression of RSA divided by tidal volume upon total respiratory cycle time is then used to estimate the baseline vagal tone for each breath of a given total respiratory-cycle time. During a subsequent analysis, the difference between the observed RSA (divided by the tidal volume at each breath) and the RSA divided by the tidal volume that was predicted by the baseline equation serves as an estimate of changes in vagal tone. rsaToolbox includes a graphical user interface for intuitive handling. Modular implementation of the algorithm also allows for flexible integration within other analytic strategies or for batch processing.

The effects of paced breathing on respiratory resistance are minimal in healthy individuals.

Paced breathing has been criticized for its presumed influences on autonomic and respiratory regulation, among that on respiratory resistance. It has been speculated that excessive pulmonary stretch receptor activation through high tidal volume (V(T)) would be the mechanism underlying such influences. However, the idea of airway dilation by paced breathing has remained untested. We analyzed inspiratory and expiratory resistance measured by forced oscillations in 26 healthy participants during baseline and two paced breathing conditions, regular pacing with instructions to alter rate only and pacing with additional instructions to alter volume randomly throughout the task. In each condition, four 3-min paced breathing trials at 8, 10.5, 13, and 18 breaths/min were administered. Despite pronounced changes in respiration rates and V(T) across pacing trials, neither inspiratory nor expiratory resistance were changed significantly under the regular paced breathing condition. A small reduction in resistance was only observed under conditions of variable volume at 18 breaths/min. Thus, regular paced breathing at different speeds across a range of naturally occurring breathing frequencies has only minimal effects on resistance of the airway passages.

Dyspnea and pain share emotion-related brain network.

The early detection of stimuli signalling threat to an organism is a crucial evolutionary advantage. For example, the perception of aversive bodily sensations such as dyspnea and pain strongly motivates fast adaptive behaviour to ensure survival. Their similarly threatening and motivating characters led to the speculation that both sensations are mediated by common brain areas, which has also been suggested by neuroimaging studies on either dyspnea or pain. By using functional magnetic resonance imaging (fMRI), we formally tested this hypothesis and compared the cortical processing of perceived heat pain and resistive load induced dyspnea in the same group of participants. Here we show that the perception of both aversive sensations is processed in similar brain areas including the insula, dorsal anterior cingulate cortex, amygdala and medial thalamus. These areas have a documented role in the processing of emotions such as fear and anxiety. Thus, the current study highlights the role of a common emotion-related human brain network which underlies the perception of aversive bodily sensations such as dyspnea and pain. This network seems crucial for translating the threatening character of different bodily signals into behavioural consequences that promote survival.

Down-regulation of insular cortex responses to dyspnea and pain in asthma.

RATIONALE: Dyspnea is the impairing cardinal symptom of asthma but its accurate perception is also crucial for timely initiation of treatment. However, the underlying brain mechanisms of perceived dyspnea in patients with asthma are unknown. OBJECTIVES: To study brain mechanisms of dyspnea in asthma. METHODS: By using functional magnetic resonance imaging we compared the neuronal responses to experimentally induced dyspnea in patients with asthma and healthy controls. These brain activations were compared with neuronal responses evoked by pain to study neuronal generalization processes to another, similarly unpleasant, physiological sensation. MEASUREMENTS AND MAIN RESULTS: While lying in the scanner, fourteen patients with mild-to-moderate asthma and fourteen matched healthy controls repeatedly underwent conditions of mild dyspnea, severe dyspnea, mild pain and severe pain. Dyspnea was induced by resistive loaded breathing. Heat pain of similar intensity was induced by a contact thermode. Whereas the sensory intensity of both sensations was rated similar by patients and controls, ratings of the affective unpleasantness of dyspnea and pain were reduced in patients. This perceptual difference was mirrored by reduced insular cortex activity, but increased activity in the periaqueductal gray (PAG) in patients during both increased dyspnea and pain. Connectivity analyses showed that asthma-specific down-regulation of the insular cortex during dyspnea and pain was moderated by increased PAG activity. CONCLUSIONS: The results suggest a down-regulation of affect-related insular cortex activity by the PAG during perceived dyspnea and pain in patients with asthma. This might represent a neuronal habituation mechanism reducing the affective unpleasantness of dyspnea in asthma, which generalizes to other unpleasant physiological sensations such as pain.

The evaluation of supervision: construction of brief questionnaires for the supervisor and the supervisee.

This study evaluated the psychometric properties of two parallel questionnaires (for the supervisor and supervisee, respectively). Ninety supervisees and 37 supervisors from different parts of Germany took part in the study. The three dimensions of clarifying, problem solving, and relationship were confirmed, but for both supervisor and supervisee versions of the scale medium intercorrelations also allowed a combined scale to be formed. In exploratory regression analysis, the relationship dimension related to both perspectives (i.e., supervisor and supervisee) served as the best predictor for overall supervision satisfaction. Despite the fact that general session satisfaction correlated in the medium range between supervisor and supervisee, there was no correlation between the perspectives as measured by the questionnaires. Possible reasons for this unexpected correlational pattern are discussed.

Associations between the perception of dyspnea, pain, and negative affect.

The perception of dyspnea shares many characteristics with the perception of pain, and both sensations might be linked to affective states. Therefore, the present study investigated the associations between perceived dyspnea, pain, and negative affect during resistive load breathing, the cold-pressor test, and affective picture viewing in healthy volunteers. Physiological and psychological measures confirmed successful experimental manipulation. There was a positive correlation between perceived dyspnea and pain in the unpleasantness dimension, but not in the intensity dimension, and this was further related to negative affect. These associations might be explained by similarities in the cortical processing of dyspnea, pain, and negative affect. The present findings extend the knowledge on similarities between dyspnea and pain and provide support for theories focusing on the perception of physiologic sensations in the development of affective states.

Reduced perception of dyspnea and pain after right insular cortex lesions.

RATIONALE: The perception of dyspnea and pain show many similarities. Initial imaging studies suggested an important role of the insular cortex for the perception of both sensations. However, little is known about the cortical processing of dyspnea. OBJECTIVES: This study investigated the influence of lesions of the insular cortex on the perception of dyspnea and pain. METHODS: Dyspnea was induced by resistive loaded breathing in four patients with right-hemispheric insular cortex lesions, as assessed with computer tomography or magnetic resonance imaging, and four matched healthy control subjects. Pain was induced by a cold-pressor test. Perceived intensity and unpleasantness of both sensations were rated on visual analog scales. MEASUREMENTS AND MAIN RESULTS: In contrast to healthy control subjects, patients with lesions demonstrated reduced perceptual sensitivity for dyspnea, in particular for the unpleasantness of dyspnea (P < 0.05). This was paralleled by reduced sensitivity for pain in patients with lesions, as reflected by smaller ratings of intensity and unpleasantness, higher sensory pain-thresholds, and, in particular, higher affect-related pain tolerance times (P < 0.05). CONCLUSIONS: The results suggest that lesions of the right insular cortex are associated with reduced sensitivity for the perception of dyspnea and pain, in particular for their perceived unpleasantness. This underlines the importance of the insular cortex for the perception of both sensations.

Psychological triggers and hyperventilation symptoms in asthma.

BACKGROUND: Anecdotal accounts have identified hyperventilation as one route through which psychological factors can trigger bronchoconstriction. However, little is known about the empirical association between psychological and other trigger factors and hyperventilation in asthma exacerbations. OBJECTIVE: To study the cross-sectional association between perceived triggers and hyperventilation symptoms in 1 British and 1 German sample of patients with asthma who were recruited from the community and from primary care clinics. METHOD: Patients completed relevant language versions of the Asthma Trigger Inventory and the Asthma Symptom Checklist. RESULTS: After controlling for demographics and asthma severity, perceived asthma triggers measured by subscales of the Asthma Trigger Inventory explained 12.5% to 37.3% of the variance in Asthma Symptom Checklist hyperventilation-hypocapnia symptoms. Psychological triggers accounted for 10.6% to 26.7% of the variance alone and 4.3% to 11.0% of the variance over and above other trigger factors. In contrast, perceived animal and pollen allergen triggers did not contribute unique variance to the hyperventilation symptom report. Psychological triggers did not explain variance in classic airway obstruction symptoms, thus arguing against a general bias toward inflated symptom reports in patients with psychologically induced asthma. CONCLUSION: Differences in perceived asthma triggers are substantially associated with hyperventilation symptoms, and patients with more frequent psychological triggers also tend to report that they experience more hyperventilation symptoms during their asthma symptom episodes.

Stress effects on lung function in asthma are mediated by changes in airway inflammation.

OBJECTIVE: To examine the association of changes in current negative mood and long-term daily hassles with changes in lung function and airway inflammation in patients suffering from asthma and in healthy controls. Associations between psychological factors and asthma symptoms have been documented, but the relationship between airway inflammation and psychological factors has been largely unexplored. METHOD: Data were analyzed from 46 asthma patients and 25 controls who completed questionnaires on current mood and daily hassles at two assessments 3 months apart. Lung function was measured by spirometry (forced expiratory volume in the first second (FEV(1))) and airway inflammation by the fraction of nitric oxide in exhaled air (FeNO). Regression analyses controlling for allergen load and air pollution (ozone) were calculated to study the association between changes in psychological factors and changes in lung function and airway inflammation, and to examine the mediational role of airway inflammation in the stress-lung function association. RESULTS: In patients with asthma, increases in negative affect were associated with decreases in FEV(1) and increases in FeNO. For daily hassles, a reverse pattern of associations was found, with decreases in daily hassles linked to decreases in FEV(1) and increases in FeNO. Mediation analyses showed that FeNO was a significant mediator of the association of both negative affect and daily hassles with lung function changes. No significant associations were found for healthy controls. CONCLUSION: Psychological variables are consistently associated with spirometric lung function and airway inflammation in asthma patients. For asthma patients, effects of acute negative affect must be distinguished from more chronic distress due to daily hassles.

Effects of 3-week outpatient pulmonary rehabilitation on exercise capacity, dyspnea, and quality of life in COPD.

The effects of intensive 3-week outpatient pulmonary rehabilitation (PR) on exercise capacity, dyspnea, and health-related quality of life (HRQL) were investigated in patients with COPD. Two hundred ten patients with COPD (mean FEV(1) = 54%pred) underwent PR consisting of exercise training, patient and psychosocial education, breathing and relaxation therapy, nutrition counseling, and smoking cessation support. Before and after PR, exercise capacity was assessed with 6-min walking tests (6MWT) and constant cycle ergometer exercise (CEE). Dyspnea was measured after 6MWTs with a Borg scale and after PR with the Transition Dyspnoea Index (TDI). HRQL was examined with the Medical Outcomes Study Short Form 36 (SF-36). Results showed improvements in the 6MWT (+39 m, p < 0.001) and CEE (+241 W x min, p < 0.001) after PR, paralleled by decreased dyspnea during the 6MWT (-0.5, p < 0.001) and during activities (TDI score = 3.6). Increases in all SF-36 subscales reflected improved HRQL after PR (p < 0.001). No gender differences were found. Patients with milder versus more severe COPD improved similarly in most outcomes. Regression analyses revealed that TDI scores were the most important predictor of improvements in HRQL. The results suggest that intensive 3-week outpatient PR is associated with improvements in exercise capacity, dyspnea, and HRQL in male and female patients with COPD irrespective of COPD severity. Reduced dyspnea during activities contributed the most to improvements in HRQL.

Effects of the premenstrual syndrome on facial expressions of sadness.

UNLABELLED: This study examined the relationship between PMS and emotion-related electromyographic facial activity at different phases of the menstrual cycle. Twenty-four women of reproductive age (12 with PMS, 12 controls) participated in two EMG sessions (T1 and T2) in which they were shown photographic images that can elicit various emotions (IAPS stimuli). T1 took place in the follicular phase, T2 in the luteal phase. The activity of the musculus depressor anguli oris ("depressor", expression of sadness) was measured. Depressor activity was compared to activity of musculus orbicularis oculi ("orbicularis"; expression of joy). ANOVA yielded a significant increase of the activity of the depressor at T2 in the PMS group. The PMS group showed more frequent depressor activity during the luteal than the follicular phase. Orbicularis activity did not change from T1 to T2. CONCLUSIONS: The PMS group experienced various visual stimuli in a more depressed way during the luteal phase.

The unpleasantness of perceived dyspnea is processed in the anterior insula and amygdala.

RATIONALE: The subjective perception of dyspnea, which is an impairing symptom in various cardiopulmonary diseases, consists of sensory (intensity) and affective aspects (unpleasantness). However, little is known about the cortical processing of the perception of dyspnea. OBJECTIVES: To investigate the cortical areas associated with the processing of the affective unpleasantness of perceived dyspnea. METHODS: Brain imaging study using functional magnetic resonance imaging in 14 healthy volunteers. MEASUREMENTS AND MAIN RESULTS: Dyspnea was induced by inspiratory resistive loaded breathing with concomitant positive and negative emotional stimulation by viewing standardized emotional picture series. The blood oxygen level-dependent contrast was measured as an index of local neuronal activity while respiration was continuously monitored. Negative emotional stimulation during loaded breathing was associated with higher unpleasantness of perceived dyspnea when compared with loaded breathing with concomitant positive emotional stimulation (P < 0.05). The levels of intensity of perceived dyspnea, respiratory responses, and load magnitude were similar between both conditions. Higher unpleasantness of dyspnea was associated with neuronal activations in the limbic system-that is, in the right anterior insula and in the right amygdala (respective Z values = 3.93 and 3.15; P < 0.05). CONCLUSIONS: The results of the present brain imaging study suggest that the unpleasantness of subjectively perceived dyspnea is processed in the right human anterior insula and amygdala.