Normal physiological emotions but differences in expression of conscious feelings in children with high-functioning autism.

To provide insight into what aspects of the emotional circuit might be affected in high-functioning autism, we measured indices of physiological emotions and of the expression of conscious feelings in 10 children with high-functioning autism or Asperger syndrome and 10 comparison participants. Pleasant, unpleasant, and neutral pictures were presented while skin conductance responses were measured. Self-report ratings of pleasantness and interestingness were taken between pictures. Skin conductance responses did not differ between the groups. Self report ratings were different, with the children with autism giving more similar answers to the two questions than the comparison children. Impairments in socio-emotional expression in autism may be related to deficits in perception and/or expression of conscious feelings; physiological emotions may be relatively preserved.

Does muscle tension reflect arousal? Relationship between electromyographic and electroencephalographic recordings.

Increased muscle tension and heightened arousal are the most consistent finding in patients with anxiety disorders. This study examined the relationship between frontalis and gastrocnemius electromyographic (EMG) and electroencephalographic activity on 14 female generalized anxiety disorder patients and 14 female control subjects. In GAD patients, gastrocnemius but not frontalis EMG was correlated with right but not left hemisphere activity. For the non-anxious subjects, there was a pattern for both beta 1 and beta 2 waves to be positively associated with both frontalis and gastrocnemius muscle tension levels. The results, while preliminary, suggest that EMG activity may reflect central nervous system arousal.

Cardiovascular reactivity to a naturally occurring stressor: development and psychometric evaluation of a psychophysiological assessment procedure.

Three studies were conducted to examine the feasibility, reactive effects of assessment, stability, sampling parameters, and sensitivity of an assessment procedure designed to measure cardiovascular responses to a discrete, naturally occurring, and replicatable stressor--university course examinations. Undergraduate students monitored their blood pressure and heart rate several times during one or two classroom examinations and for several class sessions preceding each examination. Classroom examinations were generally associated with significant increases in subjective measures of distress and cardiovascular measures. Reactive effects of assessment and other sources of error were minimized and responses were reasonably stable over time. These results support the potential utility, validity, and cost-efficiency of this methodology for assessing cardiovascular reactivity to naturally occurring stressors.

Development of an inventory for dizziness and related factors.

Dizziness is an extremely common complaint of patients, yet often goes unexplained after medical evaluation, which can lead to inappropriate treatment. There is a lack of psychometrically sound self-report instruments that measure dizziness and related factors. This study describes the application of factor analytic procedures with 184 dizzy patients' responses to develop the Dizzy Factor Inventory (DFI), a 44-item inventory divided into three sections and modeled after the Multidimensional Pain Inventory. The first section consists of symptom factors, the second concerns responses of significant others to the dizzy patient, and the third section assesses activity level. This inventory groups symptoms into empirically distinct factors that could be related in clinical and research applications to physiological and psychological processes, and could be useful for treatment planning and measuring treatment progress. Factors derived with dizzy patients are compared to factors found with chronic pain patients.

Muscle tension in generalized anxiety disorder: elevated muscle tonus or agitated movement?

The purpose of this study was to investigate the amplitude characteristics of frontalis and gastrocnemius electromyographic (EMG) activity in clinically anxious and nonanxious populations. Eighteen women with generalized anxiety disorder (GAD) and 19 nonanxious women were compared during baseline, laboratory stressor, and recovery conditions. EMG mean levels were greater for the GAD group, but there were no group differences in EMG skewness. During the stressor the GAD group had a significant reduction in frontalis EMG variability. Gastrocnemius muscle activity for both groups during the stressor condition increased in mean levels and variability while decreasing in skewness. These results indicate that clinically anxious individuals have elevated muscular tonus and have reduced variability in frontalis activity during stressful tasks. Also, the gastrocnemius muscle exhibited a stressor reactivity, whereas the frontalis did not. This study presents an approach to EMG analysis that could be useful in distinguishing unique features of anxiety as well as other emotional disorders.

Generalized anxiety disorder with early and late onset of anxiety symptoms.

Some generalized anxiety disorder (GAD) patients experience subclinical or clinical levels of anxiety before adulthood, whereas others have a later onset. To determine whether patients who experienced subclinical or clinical anxiety in the first two decades of life differed from those with a later onset, we reviewed the history, ratings on various scales, and psychophysiological recordings obtained from 103 GAD patients. Early-onset patients were younger and more likely to develop GAD without a precipitating stressful event. With the exception of depression in the early-onset group, present-state measures did not differentiate the two groups. During childhood, patients in the early-onset group were exposed to more domestic disturbances, experienced more childhood fears, and were more inhibited and socially maladjusted. As adults, they scored higher on trait anxiety and neuroticism, tended to have obsessional traits, were more sensitive in interpersonal relationships, and experienced more marital difficulties. These findings may be explained by (1) constitutional traits that make early-onset GAD patients more vulnerable to stressors; (2) a more disturbed environment during childhood that adversely affects personality development; or (3) a more severe disorder with an early subclinical onset that also affects personality development.

Fibromyalgia: a time-series analysis of the stressor-physical symptom association.

The purpose of this study was to investigate the association among daily stressors, cognitive rumination, and fibromyalgia symptoms using time-series methodology and to determine whether autocorrelation was present in the self-report data. Twelve female fibromyalgia subjects monitored their daily level of stressors, cognitive rumination, and fibromyalgia symptoms for 30-35 days. Time-series regression analyses indicated that there was a positive association between previous-day stressors and fibromyalgia symptoms for one subject and between previous-day cognitive rumination and fibromyalgia symptoms for four subjects. For 7 out of 12 subjects autocorrelation was present, and generalized least-squares methods were used with these subjects. These results indicate that ordinary least-squares methods may often not be appropriate for within-subject designs with self-report data. These results also question the often reported stressor-physical symptom association. This study illustrates a useful methodology and analysis to investigate psychosocial-physical symptom associations.