Consistency in physiological stress responses and electromyographic activity during induced stress exposure in women and men

Physiological responses serve the role as objective indicators of stress as well as a link between psychosocial stress and various health outcomes. The aim of the present exposure session was to compare different physiological stress responses (systolic and diastolic blood pressure, heart rate, urinary epinephrine and norepinephrine, salivary cortisol) as well as trapezius muscle activity, measured by surface electromyography, during mental and physical stress in 11 women and ten men. The results show significantly increased activity in all measures but cortisol and significant associations between sympathetic arousal and EMG activity. The association between sympathetic arousal and muscle activity is of importance for understanding the high prevalence of musculoskeletal disorders in mentally stressful but physically light work tasks. Men had higher blood pressure and a more pronounced increase in epinephrine output than women, whereas women had higher heart rate. It was concluded that sympathetic activity is more sensitive to moderately intense stress exposure than pituitary adrenocortical (cortisol) activity and that men respond to performance stress with more epinephrine output than women. Although the correlations between the different indicators of sympathetic arousal were high, together they could still only explain 30–70% of the inter-individual variance. Thus, several parameters are needed in order to obtain a reliable measure of sympathetic activity.     

Consistency in Physiological Stress Responses and Electromyographic Activity during Induced Stress Exposure in Women and Men

Physiological responses serve the role as objective indicators of stress as well as a link between psychosocial stress and various health outcomes. The aim of the present exposure session was to compare different physiological stress responses (systolic and diastolic blood pressure, heart rate, urinary epinephrine and norepinephrine, salivary cortisol) as well as trapezius muscle activity, measured by surface electromyography, during mental and physical stress in 11 women and ten men. The results show significantly increased activity in all measures but cortisol and significant associations between sympathetic arousal and EMG activity. The association between sympathetic arousal and muscle activity is of importance for understanding the high prevalence of musculoskeletal disorders in mentally stressful but physically light work tasks. Men had higher blood pressure and a more pronounced increase in epinephrine output than women, whereas women had higher heart rate. It was concluded that sympathetic activity is more sensitive to moderately intense stress exposure than pituitary adrenocortical (cortisol) activity and that men respond to performance stress with more epinephrine output than women. Although the correlations between the different indicators of sympathetic arousal were high, together they could still only explain 30-70% of the inter-individual variance. Thus, several parameters are needed in order to obtain a reliable measure of sympathetic activity.     

Parents' description of conduct problems in their children - a test of the Eyberg Child Behavior Inventory (ECBI) in a Swedish sample aged 3-10

The Eyberg Child Behavior Inventory (ECBI) is a widely used 36-item uni-dimensional parent rating scale constructed to measure disruptive behavior problems in children. However, in an American sample a 22-item version, including three subscales, has been suggested in order to increase the usefulness of the ECBI. Two studies were conducted to test the ECBI in a Swedish sample (N = 841). The aims of Study I were (a) examine the psychometric properties of the ECBI (b) to investigate the correspondence between mothers' and fathers' ratings, and (c) to obtain Swedish norms. The aim of Study II was to test the suggested three-factor solution in the Swedish sample using a confirmatory factor analysis (CFA). The ECBI showed good psychometric properties also in the present study, and Swedish normative data is presented. The best-fitting CFA-model was identical to the previously suggested three-factor model, which thus might be a useful alternative to the 36-item version.     

Working memory deficit in children with mathematical difficulties: a general or specific deficit?

This study examined whether children with mathematical difficulties (MDs) or comorbid mathematical and reading difficulties have a working memory deficit and whether the hypothesized working memory deficit includes the whole working memory system or only specific components. In the study, 31 10-year-olds with MDs and 37 10-year-olds with both mathematical and reading difficulties were compared with 47 age-matched and 50 younger controls (9-year-olds) on a number of working memory tasks. Compared with the age-matched controls, both groups of children with MDs performed worse on tasks tapping the central executive (e.g., visual matrix span) and the phonological loop (e.g., word span). More important, the MD group performed worse than the younger controls on the counting span task, whereas the group with comorbid mathematical and reading difficulties performed worse on the counting span task and the visual matrix span task. These findings provide support for the assumption that children with MDs have a working memory deficit. More specifically, children with MDs have a central executive deficit connected to concurrent processing and storage of numerical and visual information.     

Social fear and expressive reactions to social stimuli

This study explored whether subjects high as compared to low in social fear react with a more negative emotional response, measured as facial electromyographic (EMG) activity, when exposed to social stimuli (pictures of angry and happy facial expressions). It was found that subjects who rated themselves as relatively high in public speaking fear gave larger negative facial EMG responses (Corrugator supercilii muscle activity) to angry faces than did the low fear subjects. Low fear subjects, on the other hand, gave larger positive facial EMG responses (Zygomatic major muscle activity) to happy faces than did the high fear subjects. It was further found that happy stimuli were rated as more hostile and less friendly and happy by the high fear group. Consistent with earlier findings, it was concluded that the facial EMG technique is sensitive to detecting different reactions among subjects relatively high and low in social fear.     

GEOGRAPHICAL DATA AS PSYCHOPHYSICAL STIMULI

L undberg U. & E kman G. Geographical data as psychophysical stimuli. Scand. J. Psychol . 1972, 13 , 81–88.—Thirty-three students reported their subjective estimates of the area, the number of people, and the average population density of 44 different countries. Subjective scales were constructed for each variable and it was found that these scales could be roughly described by simple power functions of the corresponding physical scales. The subjective scales were positively related to each other, and the correlations they showed exceeded the corresponding correlations between the physical variables. Empirical estimates of population density may be described by a simple power function of the expected subjective population density with the exponent of o.63.     

TRANSITION FROM ROD TO CONE VISION: II. Successive contrast

S tabell , B. & S tabell , U. Transition from rod to cone vision. II. Successive contrast. Scad J. Psychol., 1969, 10 137–139—Transition from chromatic rod to chromatic cone activity during dark adaptation is interpreted as a kind of color mixing.     

COLOR THRESHOLD MEASUREMENTS IN SCOTOPIC VISION: Simultaneous color contrast

S tabell , U. & S tabell , B. Color threshold measurements in scotopic vision. III. Simultaneous color contrast. Scand J. Psychol ., 1968, 9, 133–137.—Color may be observed well below the break-point level of the dark adaptation curve, suggesting that the impulse pattern initiated in the rods may trigger a color-related response. Color is induced when the intensity of the inducing field reaches a certain level above the specific threshold, provided the stimulation of the test field is observable.     

A SERIAL AFTERIMAGE EXPERIMENT IN CLINICAL DIAGNOSTICS

Successive change in the size of negative afterimages repeatedly projected upon a screen was measured in a group of 87 psychiatric patients and a control group of 27. Primitive-hysteroid subjects were characterized by fluctuating serials, compulsives by small size changes of short duration, anxiety cases by progressively growing, dark, achromatic images, and psychotics by sudden contractions to size-constant or concrete images. A tentative finding for depressives was also presented and discussed.     

Perceptual Priming by Invisible Motion

When observers see motion that is not really there, they can nonetheless show evidence of motion priming. And when observers do not see motion that is really there, they also show evidence for motion priming. Evidently, the process responsible for establishing motion correspondence is sensitive to contextual information, and this sensitivity is modulated at preconscious levels of visual analysis.