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Biomedical subjects

G Schreinicke

Publications and source records attributed to G Schreinicke.

At least 19 recordsLinked to original sources

Stability of cardiovascular responses across subjects and situations: a systematic approach.

This study describes the reproducibility of behaviorally elicited cardiovascular response patterns, 111 subjects were studied over a 1-year interval. Physiological variables recorded were heart rate, systolic and diastolic blood pressure, and respiratory rate. Test-retest stability coefficients were calculated and compared with the results of a study with a 3-day interval between test sessions. The physiological data are depicted in a four-dimensional data box (subjects, situations, replications, variables), and the variance components of the factors and their interactions are estimated. Some of the interaction components are associated with specificity principles and with temporal stability. To comprehensively describe special aspects of stability, measures for stability were generated (concerning subjects, situations, or both), adopting basic ideas from the covariance partitioning approach. The stability measures were compared with simple test-retest reliability coefficients and with generalizability coefficients, and systematic relationships between the stability measures are discussed.

Adolescent↗

Stress-related changes of saliva cortisol in VDU operators.

In the field of work physiology, catecholamines and cortisol are used as strain indicators, because their production is increased in stressing work situations. Short-term stress cannot be ascertained by measuring catecholamines in urine. We studied the excretion of cortisol in saliva during short-term stress. We examined 77 healthy subjects who worked at a video display unit (VDU) for 30 min. They had to carry out a task with high speed and accuracy demands. Saliva specimens were taken before and after VDU work. Saliva cortisol levels were determined by means of a sensitive enzyme immunoassay (EIA). Additionally physiological parameters (heart rate, blood pressure, respiratory rate) and task performance were measured, and the subjects were asked about their feelings of stress and psychovegetative disorders. Saliva cortisol concentrations were significantly increased after 30 min of VDU work. Heart rate, blood pressure and respiratory rate were also increased during the task. In persons with high heart rate and blood pressure levels saliva cortisol increased significantly stronger during VDU work than in persons with lower heart rate and blood pressure levels. The results indicate that saliva cortisol is a useful strain indicator in short-term stress situations.

Adult↗

[Task specificity and reproducibility of the psychophysiologic reaction pattern].

This paper presents results from investigations of physiological activation processes concerning two subjects. Firstly: Different tasks cause different reactions of the activation variables. In our experiment the heart rate raised stronger in the mental arithmetic task than in the trakking task. Conversely, blood pressure and respiratory frequency showed higher values in the tracking task. Secondly: By analyzing the stabilities for repeated investigations we obtained the following results: a) The reliability of the physiological strain variables is higher than that of the difference values. b) Habitual values are predicted best by the second investigation. c) If the experiment is often repeated, one can determine intraindividual correlations between activation variables for every single person.

Adult↗

[Psychophysiologic particularities in patients with functional syndromes].

Patients with gastroenterological or cardiovascular functional syndromes (n = 109) were examined by means of an extensive psychological standardized diagnostic programme and psychological strain analysis was carried out under psychogenic stress in laboratory. The results were compared with healthy probands (n = 51) likewise examined. Patients with functional syndromes significantly discriminated of healthy probands by more psychosocial risk constellation under strain caused by more distress and in parameters of performance and in psychophysiological field in some strain variables (heart rate, blood pressure, acral vasomotricity) and their dynamics.

Adult↗

[Evaluation of activities in computer-supported work places from the viewpoint of occupational physiology].

Evaluation of strain resulting from mental load in computer workplaces requires a psychophysiological approach. A complex valuation of various factors (well-being, physiological parameters, parameters of performance) is essential. Vegetative parameters correlate in a non-specific way with mental strain. On the other hand, the electrical brain activity reveals specific reactions to information processing. Actual trends of psychophysiological evaluation of mental strain are discussed as well as some conclusions for practical questions.

Brain↗

[Parameters of acral vasomotor activity--sensory arousal variables in psychological stress].

By means of complex methods in 65 test persons from a large number of parameters the photopulse amplitude and the rheographic quotient at the finger apart from the heart rate and the blood pressure were established as very sensitive demand variables under psychic stress. The temporary and formal criteria of the volume pulse curves are less well suitable for this purpose. In the different reaction patterns the inclusion of sensitive biosignals of the acral vasomotricity is an information gain for the demand diagnostics under psychic stress.

Adult↗

[Comparative studies in young hypertensive patients at rest and after standardized physical and sensomotoric exertion].

The acknowledged role of central-nervous mechanisms in the etiopathogenesis of the essential arterial hypertension led to the use of a psycho-physiologic test method with the aim of the early recognition of stress-induced permanent changes of physiologic functions. We succeed in proving the chosen sensumotoric stress in a group of patients with essential arterial hypertension which at first appears uniform in clinical respect allows a further differentiation. On the basis of the behaviour of defined physiologic and biochemical parameters after physical and sensumotoric stress it is referred to the necessity of a differentiated therapy of the early form of the essential arterial hypertension.

Adult↗

[Individual differences in heart and respiration rate of subjects exposed to various sensomotor loads].

Three groups were established according to the reactivity of the heart and respiration rates in sensomotor tasks: Group 1: especially reacting by changes in heart rate during performance of the tasks; group 2: especially reacting by changes of the respiration rate during the tasks; group 3: subjects without differences in the changes of the heart and respiration rates. The group 1 (heart-rate-type) shows a significantly higher level of the heart rate already during the "rest" in comparison with the other groups and presents a larger increase during the sensomotor tasks, too. The respiration rate corresponds to group 3. In contrast to group 1, group 2 (respiration-rate-type) shows no differences in the level of the respiration rate during "rest", however, the increase in respiration rate is significantly greater than in the other groups during sensomotor tasks. In this group the heart rate corresponds to group 3. No significant differences between the groups were noted in the heart rate variability, in the results of the sensomotor tasks and the filling in of the INR- and VELA-questionnaires.

Adult↗

[Behavior of physiological parameters and performance in a compensatory tracking task from the standpoint of aptitude judgements (author's transl)].

Activation behavior and performance were examined in twenty five subjects participated in a compensatory tracking task. The employed physiological parameters were useful for demonstration of interindividual differences in the activation behavior, personality characteristics are considered. Groups were formed according to the level of heart rate, arrhythmia, respiratory rate and level of performance. It was shown that exists a relation between activation level and performance. With regard to the relation between activation and performance may be derived psychophysiological aptitude judgements.

Adult↗