Electromyographic and affective responses of episodic tension-type headache patients and headache-free controls during stressful task performance

Does Tension Headache Have a Central or Peripheral Origin? Current State of Affairs

PURPOSE OF REVIEW

The aim of this narrative review is to analyze the evidence about a peripheral or central origin of a tension headache attack in order to provide a further clarification for an appropriate approach.

RECENT FINDINGS

Tension headache is a complex and multifactorial pathology, in which both peripheral and central factors could play an important role in the initiation of an attack. Although the exact origin of a tension headache attack has not been conclusively established, correlations have been identified between certain structural parameters of the craniomandibular region and craniocervical muscle activity. Future research should focus on improving our understanding of the pathology with the ultimate goal of improving diagnosis. The pathogenesis of tension-type headache involves both central and peripheral mechanisms, being the perpetuation over time of the headache attacks what would favor the evolution of an episodic tension-type headache to a chronic tension-type headache. The unresolved question is what factors would be involved in the initial activation in a tension headache attack. The evidence that favors a peripheral origin of the tension headache attacks, that is, the initial events occur outside the brain barrier, which suggests the action of vascular and musculoskeletal factors at the beginning of a tension headache attack, factors that would favor the sensitization of the peripheral nervous system as a result of sustained sensory input.

Tension-type headache

Tension-type headache (TTH) is the most prevalent neurological disorder worldwide and is characterized by recurrent headaches of mild to moderate intensity, bilateral location, pressing or tightening quality, and no aggravation by routine physical activity. Diagnosis is based on headache history and the exclusion of alternative diagnoses, with clinical criteria provided by the International Classification of Headache Disorders, third edition. Although the biological underpinnings remain unresolved, it seems likely that peripheral mechanisms are responsible for the genesis of pain in TTH, whereas central sensitization may be involved in transformation from episodic to chronic TTH. Pharmacological therapy is the mainstay of clinical management and can be divided into acute and preventive treatments. Simple analgesics have evidence-based effectiveness and are widely regarded as first-line medications for the acute treatment of TTH. Preventive treatment should be considered in individuals with frequent episodic and chronic TTH, and if simple analgesics are ineffective, poorly tolerated or contraindicated. Recommended preventive treatments include amitriptyline, venlafaxine and mirtazapine, as well as some selected non-pharmacological therapies. Despite the widespread prevalence and associated disability of TTH, little progress has been made since the early 2000s owing to a lack of attention and resource allocation by scientists, funding bodies and the pharmaceutical industry.

Acute Tension-Type Headaches Are Associated with Impaired Cognitive Function and More Negative Mood

BACKGROUND/AIMS

Research has shown that migraine is often associated with memory problems. There have, however, been few studies of tension-type headache (TTH) and cognition. People who report frequent headaches often report high levels of negative affect. However, less is known about the acute effects of TTH on mood. To address these gaps in our knowledge, two studies examined the effects of acute TTH on -cognitive performance and mood.

METHODS

Both studies involved one group of participants completing a battery of tasks when they had a TTH and when they had no headache. Another group (the control) was headache free on both occasions. Duration of the headache was >30 min and <4 h. In the "no headache" condition, the participants were headache free for at least 24 h. In the first study, 12 participants (6 with TTH and 6 controls) completed a computerized battery measuring mood and aspects of cognition. In the second study, 22 participants (7 TTH, 5 after TTH, and 10 controls) completed paper and pencil mood and cognitive tasks.

RESULTS

In the first study, having a headache was associated with an increase in negative affect both before and after the tasks. Three performance tasks showed impairments when the participants had headaches: logical reasoning was slower and less accurate; retrieval from semantic memory was slower; and reaction times in the categorical search task were slower. Results from the second study confirmed the global increase in negative affect when the person has a TTH. The results confirmed the impairments in the logical reasoning and semantic processing tasks, and also showed that those with a TTH had greater psychomotor slowing and were more easily distracted. Effects did not continue after the headache had gone.

CONCLUSION

Two small-scale studies have shown that TTH is associated with negative affect and impaired cognitive function. It is now of interest to determine whether OTC treatment can remove these effects.

Stress and tension-type headache mechanisms

Stress is widely demonstrated as a contributing factor in tension-type headache (TTH). The mechanisms underlying this remain unclear at present. Recent research indicates the importance of central pain processes in tension-type headache (TTH) pathophysiology. Concurrently, research with animals and healthy humans has begun to elucidate the relationship between stress and pain processing in the central nervous system, including central pain processes putatively dysfunctional in TTH. Combined, these two fields of research present new insights and hypotheses into possible mechanisms by which stress may contribute to TTH. To date, however, there has been no comprehensive review of this literature. The present paper provides such a review, which may be valuable in facilitating a broader understanding of the central mechanisms by which stress may contribute to TTH.

Implicit associations in tension-type headaches: a cognitive analysis based on stress reactivity processes

OBJECTIVE

To determine whether tension-type headache (TTH) patients display stronger associations between negative events and headache-related information than headache-free controls.

BACKGROUND

Generally, stress/diathesis models are common in clinical research and in the context of TTHs specifically. Data involving stress reactivity processes are compatible with such models. However, it would be of interest to tap the associative cognitive processes that likely mediate such relations.

METHODS

In the present study, we selectively recruited individuals who do (n = 19) and do not (n = 19) suffer from episodic TTHs. We examined implicit associations between negative evaluations and headache-related information through the use of an implicit association test.

RESULTS

As hypothesized, TTH patients displayed associations between negative evaluations and headache-related information, whereas the control group did not.

CONCLUSIONS

These data provide initial support for a plausible cognitive model for the occurrence of TTHs among predisposed individuals.

An exploratory study of subgrouping of patients with functional somatic syndrome based on the psychophysiological stress response: its relationship with moods and subjective variables

OBJECTIVE

To study the characteristics and subjective estimations of subgroups of patients with functional somatic syndrome (FSS). A characteristic in patients with FSS was reportedly hyporeactivity in the psychophysiological stress response (PSR).

METHODS

The PSR was measured in 59 FSS patients and 41 healthy controls. Autonomic lability scores (ALSs) of six psychophysiological measurements on PSR were calculated. Cluster analysis using the ALSs was performed in the FSS group. A discriminant analysis was also performed to identify the criterion of the subgrouping. Factor analysis scores of the six ALSs, and moods and subjective variables were compared between the subgroups.

RESULTS

Cluster analysis divided the FSS patients into two clusters. Three groups (low-lability, high-lability, and control groups) were compared. All factor scores of autonomic lability significantly differed between the low- and high-lability groups, and between the low-lability and control groups. The mood scores were higher in the high-lability group than in the low-lability group. The duration of suffering was significantly longer in the high-lability group than in the low-lability group. The distributions of symptoms and diagnosis did not significantly differ between the subgroups.

CONCLUSIONS

We have tentatively verified that there are two subgroups based on the autonomic lability among FSS patients, which were independent of the type of symptoms and diagnostic category. Autonomic lability is an important axis in the multiaxial diagnosis of FSS.

Tension-type headache and psychiatric comorbidity

Much of the contemporary literature on headache disorders focuses on migraine headaches, despite the fact that tension-type headache (TTH) is highly prevalent and can be as debilitating as migraines. This article reviews the current literature on prevalence rates of psychiatric disorders in TTH populations, psychologic factors associated with TTH, and psychiatric disorders and their relationships with treatment outcomes in TTH. Key conclusions of this review include 1) prevalence rates of TTH vary across clinical and population-based samples; 2) greater TTH chronicity is associated with increased affective distress; 3) Axis II personality disorders may play an important role in TTH prevalence rates and psychologic functioning but have been understudied to date; and 4) maladaptive coping is common in persons with TTH.

Toward an understanding of the determinants of anger

Research bearing on several popular conceptions of the major determinants of anger arousal indicates that the particular appraisals often identified as causes of anger frequently only serve to affect the intensity of the anger that is generated. Research into effects of physical pain or other physically unpleasant conditions or involving social stresses suggests that decidedly aversive conditions are a major spur to anger. Experiments are also reviewed showing that anger-related muscular movements can also lead to anger-related feelings, memories, cognitions, and autonomic responses. Alternative explanations for the findings are discussed. The authors urge emotion theorists to widen their methodology and analyses so that they give careful, detailed attention to the many different factors that can influence anger.

Development of a multi-channel exploratory battery for psychophysiological assessment: the Stress Profile

OBJECTIVE

As the expanding field of psychophysiology is currently demanding applied methodologies to be used in the clinic, this study aimed to develop a practical multi-channel exploratory battery for psychophysiological evaluation of stress (the Psychophysiological Stress Profile; PSP). The PSP records 6 psychophysiological variables and it is designed to be mainly used in the daily clinic. Moreover, the PSP was intended to be 'the method' to obtain normative and individual psychophysiological patterns, providing relevant information for the therapeutic process.

METHODS

Two hundred and three subjects were evaluated with the PSP in two different contexts: the natural environment and the laboratory. Factorial analysis was applied to obtain psychophysiological profiles. These profiles are based on the covariation among different system responses. The Burt and Tucker Congruence Coefficient was used to compare factorial structures.

RESULTS

A 3-factor structure was obtained in both contexts, Congruence Coefficient indicates that these factorial structures are very similar, indicating the existence of a unique and consistent psychophysiological pattern that characterizes the sample.

CONCLUSIONS

The identified factorial structure shows relevant activation patterns, offering a comprehensive view of the subject's functioning. The structure is consistent through samples and can be considered as normative data for the studied population. PSP has turned out to be a quick and easy-to-use psychophysiological battery that has shown adequate internal consistency for all the recorded variables. In this way, the PSP methodology shows its practical value and usefulness in the assessment process.

Tension-type headache and stressful events: the role of selective memory in the reporting of stressors

This study examined evidence for the role of selective memory for stressful events in women with headache. Previous studies have reported that on retrospective measures of stress, those with tension-type headache report more stressful events and rate the events as more stressful than did headache-free controls. However, when ratings are made concurrently, participants with headache and controls did not differ in their ratings of equivalent stressors presented in the laboratory. One theory for why differences are found in stress ratings made retrospectively, but not concurrently, is that selective memory biases recollection of past events in patients with headache. This study compared self-report ratings of stressful events and their perceived impact made either concurrently or retrospectively to determine if selective memory might explain the discrepancies found in earlier studies. Participants included 20 patients with tension-type headache and 22 headache-free controls. Participants were compared on hourly, daily, and weekly measures of stressors and their perceived impact via hourly and nightly visual analog scale ratings, the Daily Stress Inventory, and the Weekly Stress Inventory. If support was to be offered to the hypothesis that selective memory biases the retrospective memory of patients with headache, then an interaction between group assignment (ie, headache versus control group) and time of rating would be expected. No such interaction occurred. Results from the study suggest that all participants have a tendency to overestimate stress on retrospective measures, but that patients with headache do not do so at a significantly different rate than do headache-free controls. The alternative hypothesis that patients with headache tend to appraise everyday events as more stressful is supported.

Anger, depression, and coping interactions in headache activity and adjustment: a controlled study

OBJECTIVE

To determine if individuals in the general community with chronic headache or migraine differ in terms of anger, depression, and coping strategies and from headache-free individuals in terms of anger and depression.

METHOD

A community sample comprising 16 chronic tension-type headache (CTH), 28 migraine headache (MH), and 38 headache-free control subjects (CNT) were compared on measures of anger, depression, and use of various coping strategies. Affective and coping measures, recorded during a headache-free period, were regressed on headache activity measured in a daily diary over the following 2 weeks. Relationships between anger, depression, and coping were also examined in each of the headache groups.

RESULTS

The MH subjects were found to use less effective coping strategies than controls and CTH, while the CTH group had higher levels on depression and various anger scales compared to controls and MH. Direct positive relationships were observed between suppressed anger and depression in the MH group, and between trait anger and depression in the CTH group. Anger and coping were predictive of headache activity in the following 2 weeks for both MH and CTH groups, while depression and coping, compared to coping only, were predictive of lifestyle interference from head pain in MH and CTH, respectively.

CONCLUSION

The results support a relationship between affective and coping factors in headache activity and adjustment.

The comparison of individuals with recurrent tension-type headache and headache-free controls in physiological response, appraisal, and coping with stressors: a review of the literature

It is widely accepted that stress plays an important role in the experience of tension-type headache. This article reviews the literature in which individuals with recurrent tension-type headache are compared to headache-free controls in the experience and appraisal of stress, psychophysiological response to stress, and coping with stress. A modified and extended version of the transactional model of stress as it might apply to tension-type headache is used to organize the relevant literature. In summary, there is evidence to suggest that individuals with recurrent tension-type headache experience more stressful events and are more sensitive and have a lower threshold to pain. There are some suggestions that headache sufferers may use different coping strategies for stress and pain. There is little evidence of differences in physiological responses to stressful events. The shortcomings of this body of literature are addressed and directions for future research are identified.

[Classification of patients with tension headache: irrationality, self-communication, stress reactions and pain.]

INTRODUCTION

A review of the literature suggests that patients with tension headache do not differ from normals as much as from each other in psychological traits. The aim of the present study was to identify psychological subtypes of tension headache patients.

METHOD

The subjects were 130 inpatients with a diagnosis of recurrent tension headache who were treated in a pain clinic. Six factors measured the constructs irrationality, positive and negative self-communication, emotionality, affective pain and situational pain.

RESULTS

Hierarchical agglomerative cluster analysis allowed the identification of five subtypes of patients. The reclassification rate was 95%. All patients endorsed, to a high degree, pain adjectives that expressed obstinate-refractory pain qualities. Most, i.e. 81%, indicated that they suffered from affective pain: 51.5% reported high situation-dependent and affective pain. They were comprised by two clusters, 30% showing high irrationality/negative self-communication and low positive self-talk communication and 21.5%, the opposite profile. A further 30% of the patients suffered from affective pain but reported no stimulus dependence. They were divided into two groups: 17% reported high, whereas 13% reported low positive self-communication. In 18.5% of cases the patients reported no psychological causation and demonstrated a state of inner placidity and low irrationality.

DISCUSSION

The results are discussed with reference to the literature and to indications for psychological treatment interventions.

The application of generalizability theory to surface electromyographic measurements during psychophysiological stress testing: how many measurements are needed?

Generalizability theory is an extension of classical reliability theory that allows multiple sources of measurement error in an experimental design to be investigated simultaneously. In the present study, generalizability theory was used to evaluate measurement error in psychophysiological test procedures used to differentiate tension headache patients from normal controls based upon measures of electromyographic (EMG) responding. Thirty-three subjects who met diagnostic criteria for tension-type headache and 40 normal control subjects who rarely or never experienced headache participated in two laboratory sessions. EMG activity of head and neck muscles was recorded while subjects performed baseline, relaxation, choice reaction time, psychomotor tracking, and cold pressor tasks. Variance components were computed for an experimental design having subjects nested within experimenters and crossed with sessions and replications. Generalizability coefficients were computed for combinations of various numbers of sessions and replications. The generalizability of EMG measures was highly variable, depending on the experimental conditions in force. The largest sources of measurement error were attributed to the unique responsiveness of individual subjects under a particular set of treatment conditions. For some stress tests currently in use, data from several testing sessions may need to be averaged in order to achieve acceptable levels of generalizability. Generalizability greater than 0.80 can be expected only rarely when data are collected during a single session. In the research setting, low generalizability may account for the failure of EMG-based stress tests to differentiate tension headache patients from controls during stressful task performance. In the clinical setting, the generalizability of information derived from "stress profiling" or muscle "scanning" techniques, which depend on results obtained during a single testing session, is doubtful.