PubMed Health⌕ Search

Biomedical subjects

T F Meijman

Publications and source records attributed to T F Meijman.

At least 19 recordsLinked to original sources
PubMed2004

Free recall of pleasant words from recency positions is especially sensitive to acute administration of cortisol.

In a recent study we investigated the acute effects of cortisol administration in healthy male volunteers on free recall of pleasant, unpleasant, and neutral nouns using a between-subjects double-blind placebo-controlled design. The volunteers were administered 10 mg of hydrocortisone or placebo between 9:00 and 10:30. Two hours after administration of cortisol a decline in recall of neutral and pleasant words was found, while recall of unpleasant words did not change. These results are consistent with a possible inhibitory influence of cortisol on a prefrontal dopaminergic mechanism involved in approach and positivity bias. In this paper we first explain why this interpretation would predict recall of pleasant words from recency positions to be especially sensitive to cortisol administration. Comparing primacy and recency recall of pleasant and unpleasant words, there proved to be a selective decline in recall of pleasant recency words. These results did not appear to stem from differences in recall strategies between our groups of volunteers.

Adolescent↗
PubMed2003

Need for recovery from work related fatigue and its role in the development and prediction of subjective health complaints.

AIMS: To present the available empirical evidence for the assumed position of the concept of work related fatigue as: (1) short term effect of the working day; and (2) an intermediate variable between work demands and the development of subjective health complaints and sickness absence. METHODS: Results from six single occupation studies, conducted between 1996 and 2002, are presented. Work demands (working hours, decision latitude, break control/autonomy, and mental, emotional, and physical demands) were assessed through validated scales. Work related fatigue was represented and assessed by means of the need for recovery after working time scale in all studies. Subjective health complaints and duration of sickness absence were quantified with the same instruments in most studies as well. Both cross sectional studies (four) as well as prospective studies (two; up to two years follow up) were performed. Cross sectional data of 3820 workers, in total, were available. Prospective data were accessible for 1200 workers in industry and health care. Models were tested with stepwise multiple regression analyses. RESULTS: Strong associations between work demands and need for recovery were found in different occupations. The variance explained in need for recovery by work demands, age, and (baseline) need for recovery ranged between 14% and 48% in both types of studies. The amount of explained variance by work demands, age, and (baseline) need for recovery in subjective health complaints ranged between 24% and 58% in the different occupations. The prospective data showed the prognostic value of need for recovery in relation to subjective health complaints (in terms of psychosomatic complaints, emotional exhaustion, or sleep problems) and duration of future sickness absence. CONCLUSIONS: The hypothesised role for work related fatigue as a link in the causal string of events, that is assumed to exist between repeated adverse work demands and the development of work related stress reactions, (psychological) overload and, eventually, health problems, was confirmed.

Adult↗
PubMed2001

The relation between work-induced neuroendocrine reactivity and recovery, subjective need for recovery, and health status.

OBJECTIVES: The purpose of this cross-sectional study with repeated measurements was to find out to what extent neuroendocrine reactivity during work and neuroendocrine recovery from work, and work characteristics, are related to subjective need for recovery and perceived health status. METHODS: Neuroendocrine reactivity and recovery were studied in 59 subjects by measuring urinary adrenaline and cortisol repeatedly during five consecutive days. Measures of work characteristics, subjective need for recovery, and health status were obtained by self-reports. Two hierarchical multiple linear regression analyses were performed. RESULTS: The work characteristics alone explained 39% and 28% of the variation in subjective need for recovery and health status, respectively, while these figures rose to 49% and 53% in the full models. Significant neuroendocrine contributors were found for cortisol in reactivity during work and recovery immediately after work and recovery during the day off-work, and for adrenaline in baseline level and recovery during the day off-work. Job characteristics contributed significantly as well. CONCLUSION: Both neuroendocrine measures and work characteristics were predictors for the amount of perceived need for recovery after work as well as for health status. The results are consistent with the cognitive activation theory of stress.

Adult↗
PubMed2001

Vagal cardiac control throughout the day: the relative importance of effort-reward imbalance and within-day measurements of mood, demand and satisfaction.

The effects of variables derived from a work stress theory (the effort-reward imbalance theory) on the power in the high frequency (HF_HRV) band of heart rate (0.14-0.40 Hz) throughout a work day, were determined using multilevel analysis. Explanatory variables were analysed at two levels: at the lowest level (within-day level), the effects of positive mood, negative mood, demand, satisfaction, demand-satisfaction ratio, and time of day were assessed. At the highest level (the subject level), the effects of sleep quality, effort, reward, effort-reward imbalance, need for control, type of work (profession), negative affectivity, gender and smoking on HF_HRV were assessed. Need for control has a negative effect on HF_HRV after controlling for time of day effects, i.e. subjects with a high need for control have a lower vagal control of the heart. In the long run, these subjects may be considered to be at increased health risk, because they have less of the health protective effects of vagal tone. The interaction between effort-reward imbalance and time of day has a positive effect on HF_HRV, i.e. the cardiac vagal control of subjects with a high effort-reward imbalance increases as the day progresses. It is discussed that this probably reflects reduced effort allocation, ensuing from disengagement from the work demands.

Adult↗
PubMed2000

Cortisol secretion throughout the day, perceptions of the work environment, and negative affect.

The effects of explanatory variables derived from a work stress model (the effort-reward imbalance model) on salivary cortisol were assessed. A multilevel analysis was used to distinguish the effects of single occasion and multiple occasion measurements of work stress and effect on cortisol. The single (or cross-sectional) factors include Effort-Reward Imbalance (ERI), need for control, negative affect, and other enduring factors (type of occupation, gender, and smoking). The multiple occasion measurements include momentary negative mood, Momentary Demand-Satisfaction Ratio (MD-SR), sleep quality, work load (workday versus day off), at work (versus not being at the workplace), and lunch. The effect of time of day on cortisol was controlled for before the effects of these variables were determined. Momentary negative mood but not trait negative affect was positively associated with ambulatory measured cortisol. The variables from the work stress model--effort, reward, need for control, and the multiple occasion measurements of demand and satisfaction--did not affect cortisol. As could be expected, time of day had an effect on cortisol, but a hypothesised interaction with momentary negative mood was not found. Additionally, the results show that the time course of cortisol differs between individuals and that the effect of sleep quality on cortisol can vary from person to person. This points to the necessity of continued efforts to single out sources of individual variability. The finding that variables derived from the effort-reward imbalance model are not related with cortisol does not support the hypothesis that ERI leads to short-term changes in cortisol, indicating no relation with hypothalamic-pituitary-adrenal (HPA) axis activity. On the other hand, the present results invite further qualification of negative affect as a potential determinant of HPA activity, at least, as far as can be deduced from cortisol measurements.

Adult↗
PubMed2000

Immediate and delayed after-effects of long lasting mentally demanding work.

This study investigates the hypothesis that long lasting mental work demands are reflected in after-effects on attention demanding post-test probe tasks. Sixteen subjects were engaged in 2 simulated workdays consisting of mentally demanding tasks. On the difficult day the afternoon consisted of highly demanding information processing tasks; on the easy day the demands during the afternoon were low. The mornings of both days were equally demanding. At the start (pre-test) and the end (post-test) of both days, after 5 min (immediate post-test) as well as after approximately 2 h of recuperation (delayed post-test), a probe task was carried out. A memory-search task (varied mapping) is used as probe task. After-effects were expected in terms of a shift in the ratio between performance and effort on the post-test probe tasks compared with the pre-test probe task. Performance measures were reaction time and errors; effort was indicated by heart rate variability in the 0.07-0. 14 Hz band, referred to as 0.1 Hz component. Dayload manipulation appeared to be effective because of the load-related differences between the urinary excretion rates of adrenaline during both afternoons. Compared with the pre-test, only the number of errors was significantly increased in the post-test, carried out immediately at the end of the difficult afternoon. However, compared with the easy day, in the delayed post-test probe task after the difficult day, subjects tended to shorten reaction times, made significantly more errors, and invested significantly less effort. Moreover, at that time they felt more fatigued and deactivated as indicated by the results of the 'Scale of Experienced Load' (SEB) (fatigue) and 'Groninger Adjective Checklist' (GACL) (mood) questionnaires. The observed shift towards low-effort, more 'risky' task strategies in the post-tests fits well with Hockey's (1993) fatigue after-effects degradation pattern expected after periods of high workload. The repeated measurement of the relation of performance, effort and feelings reveals the dynamics of the pattern of fatigue after-effects over the (recovery) time.

Adult↗
PubMed2000

Reactivity and recovery from different types of work measured by catecholamines and cortisol: a systematic literature overview.

OBJECTIVES: To review occupational health, laboratory, and sports literature on neuroendocrine reactivity and recovery from mental, combined mental and physical, or physical tasks. METHODS: A systematic literature search was performed in eight databases. Studies with catecholamines or cortisol as effect variables measured in blood, urine, or saliva were included. RESULTS: After application of inclusion and exclusion criteria, 77 studies from the initial 559 identified were taken into account. In occupational settings it was found that relatively few studies were conclusive about recovery, which formed a contrast with sports research. For reactivity and recovery up to 1 hour after performing the task, half of the studies considered physical tasks and more than two thirds showed incomplete recovery compared with baseline excretion of catecholamines and cortisol. Recovery extending to 3 days after the task was performed was often incomplete for cortisol after combined mentally and physically demanding tasks, and less often after solely mental or physical tasks. This type of recovery was more often incomplete for adrenaline (epinephrine) than for noradrenaline (norepinephrine), which was the case after mental as well as combined mental and physical tasks. CONCLUSIONS: The results from laboratory and sports research may be transferable to some occupations, but more research is needed on the course of recovery relative to health effects in occupational settings.

Biomarkers↗
PubMed2000

Neuroendocrine reactivity and recovery from work with different physical and mental demands.

OBJECTIVES: The purpose of this study was to examine the extent to which the type or nature (physical, mental or mixed mental and physical) of work and work characteristics is related to the course of neuroendocrine reactivity and recovery from work. METHODS: Neuroendocrine reactivity and recovery were studied by measuring the urinary excretion of adrenaline, noradrenaline, and cortisol during and after 3 workdays, 1 consecutive day off, and a baseline day. The assessment was made in 3 groups of Dutch male workers (N=60) who differed in the nature (mental, physical, and combined mental and physical demands) of their work. Multilevel analyses were performed to fit linear mixed-effects models for each hormone. RESULTS: Main or interaction effects with time of day were found between the workers in combined mental and physical work and the 2 other groups of workers for cortisol, adrenaline, and noradrenaline excretion. In addition, the baseline levels of the 3 hormones were higher in the workers with combined mental and physical work when compared with the other 2 groups. The excretion rates during the workdays were higher than those on the day off, but a trend towards mobilizing less activity was found from the 1st to the 3rd workday. Job demands were negatively related to cortisol excretion. Job control and social demands at work did not affect the excretion rates of the hormones. CONCLUSIONS: Unfavorable effects on cortisol and adrenaline reactivity or recovery was found for workers with combined mental and physical demands when compared with workers doing mainly mental or mainly physical work. The results of the present study are in accordance with the cognitive activation theory and the allostatic load model.

Adult↗
PubMed2000

Mental fatigue and task control: planning and preparation.

The effects of mental fatigue on planning and preparation for future actions were examined, using a task switching paradigm. Fatigue was induced by "time on task," with subjects performing a switch task continuously for 2 hr. Subjects had to alternate between tasks on every second trial, so that a new task set was required on every second trial. Manipulations of response-stimulus intervals (RSIs) were used to examine whether subjects prepared themselves for the task change. Behavioral measurements, event-related potentials (ERPs), and mood questionnaires were used to assess the effects of mental fatigue. Reaction times (RTs) were faster on trials in which no change in task set was required in comparison with switch trials, requiring a new task set. Long RSIs were used efficiently to prepare for the processing of subsequent stimuli. With increasing mental fatigue, preparation processes seemed to become less adequate and the number of errors increased. A clear poststimulus parietal negativity was observed on repetition trials, which reduced with time on task. This attention-related component was less pronounced in switch trials; instead, ERPs elicited in switch trials showed a clear frontal negativity. This negativity was also diminished by time on task. ERP differences between repetition and switch trials became smaller with increasing time on task.

Adolescent↗
PubMed1999

The effect of depressive symptomatology on plasma cortisol responses to acute bicycle exercise among post-menopausal women.

The present study was designed to elucidate the effect of depressive symptomatology on the cortisol response to strenuous exercise. Thirteen healthy, post-menopausal women participated in this study. The results show that acute bicycle exercise activates the hypothalamic-pituitary-adrenal (HPA) axis resulting in rapid increases in plasma cortisol. Concerning the effect of depressive symptomatology on cortisol release during physical performance, we found a trend toward a negative relation between the level of depression and the change in cortisol measured after termination of the exercise, but it failed to reach statistical significance, probably due to the small sample size. Interestingly, we found a significant negative correlation between basal cortisol levels and cortisol release to the exercise protocol. Although this finding is preliminary, it seems to suggest that a sustained activation of the HPA axis may coincide with an adrenal insufficiency in response to physical performance of post-menopausal women.

Bicycling↗
PubMed1998

Bussy business: how urban bus drivers cope with time pressure, passengers, and traffic safety.

Adhering to the schedule, providing service to passengers, and driving safely are among the most important psychosocial demands of the bus driver's job. The ways bus drivers cope with these varying and conflicting demands are addressed in this article, which uses data from 4 interrelated studies. In a large-scale questionnaire study (Study 1), behavioral styles in coping with these psychosocial demands were identified. Next, in Studies 2 and 3, the relations of these styles with well-being and health status were examined. Study 4 addressed the coping process during work itself by examining the relations among objective workload indicators, perceived effort, and psychophysiological stress reactions during work.

Adaptation, Psychological↗
PubMed1996

Behavioral determinants of occupational exposure to chemical agents.

In the demand-control model (see T. Theorell & R. A. Karasek, 1996), it is hypothesized that workers in active jobs (high demands-high decision latitude) can exert effective coping strategies when confronted with environmental stessors. Thus, when exposed to similar levels of a chemical agent, lower concentrations of this agent in blood could be expected in these workers in comparison with workers in passive jobs. This theory was tested in 2 studies of lead-exposed workers: 18 male Caucasian workers from an electric accumulatory factory and 18 male Caucasian workers from a lead smelting factory. The results did not follow the hypothesized outcomes. In the work environment of the workers in active jobs, lower concentrations of lead in air were measured, but higher levels of lead in blood were observed in these workers. The opposite was true of workers in passive jobs. Differences in hygienic behavior at work may explain these unexpected results.

Adaptation, Psychological↗
PubMed1996

Health complaints and working conditions experienced in relation to work and age.

OBJECTIVES: The main objective is to describe the potential health and work problems of the aging employees in the Dutch working population. In this way, we can identify groups at extra risk of specific health problems. METHODS: In The Netherlands, occupational health services gather questionnaire data about work and health as part of periodical occupational health surveys (POHSs). These data from the POHSs of complaints about health and working conditions, aggregated into occupational groups and age categories, are used to provide indications for groups at extra risk of specific health problems. These problems are assessed by overviews of the relation between age and complaints about health and working conditions. RESULTS: Almost all of the health questions show an increase in health complaints with increasing age. White collar workers, especially the high grade white collar workers, usually have lower complaint percentages on health questions than blue collar workers. Female employees have relatively high complaint percentages on the health questions. Differences between occupational groups in the complaints about work and working conditions reflect the differences in work demands and exposure. The relation between age and work complaints is generally inconsistent and weak. The complaint percentages on work questions of female employees tend to be equal to or lower than those of the male employees. CONCLUSIONS: The absence of a clear increase of work complaints with advancing age in the presence of a decrease in health and working capacity may be explained by a selective turnover in the working population, especially in demanding occupations. To enhance the work participation of older employees it may be necessary to reduce the work demands and to increase decision latitude.

Adult↗
PubMed1995

Employment after rehabilitation for musculoskeletal impairments: the impact of vocational rehabilitation and working on a trial basis.

OBJECTIVE: To investigate to what extent vocational rehabilitation and working on a trial basis have an impact on employment after rehabilitation. DESIGN: Follow-up survey, conducted in 1991, among all patients, aged 14 to 64, who were treated between 1984 and 1987. SETTING: An out-clinic department of a rehabilitation center in the west of The Netherlands. SUBJECTS: 395 patients (59% of the original sample) participated in the study. They suffer from musculoskeletal impairments due to back pain (41%), brain injury (20%), neurological disorder (12%), trauma to the upper and/or lower extremities (8%), rheumatoid arthritis (7%), or other disorders (12%). No differences were found between those who did and those who did not respond with regard to age, gender, marital status, disorder, work experience, and participation in vocational rehabilitation. MAIN OUTCOME MEASURE: Odds ratio of having a paid job after rehabilitation. RESULTS: Participation in vocational rehabilitation and working on a trial basis depends on age, gender, work experience, and disorder. When statistically controlled for these variables vocational rehabilitation (odds ratio 1.96; 95% confidence interval 1.12 to 3.42) and working on a trial basis (odds ratio 3.26; 95% confidence interval 1.74 to 6.11) proved to have a significant impact on employment after rehabilitation. CONCLUSIONS: The findings suggest that rehabilitation programs that aim specifically at promoting employment for people with disabilities are effective, in particular when they take place in both a laboratory and a natural setting. The validity of this suggestion must be further tested by means of an experimental design.

Adolescent↗
PubMed1995

Lorry drivers' work stress evaluated by catecholamines excreted in urine.

OBJECTIVES: To evaluate lorry drivers' work stress by measurement of adrenaline and noradrenaline excreted in the urine, and to find out which factors in their working situation are related to the excretion rates of these catecholamines. METHODS: The urinary excretion of adrenaline and noradrenaline of 32 lorry drivers, who also had loading and unloading activities to perform, was studied for one working day and one rest day. Each driver was asked to provide six urine samples on both days. RESULTS: For all samples, except the first (overnight) sample, the excretion rates of both catecholamines on the working day were higher than those on the rest day. Hierarchical multiple regression analyses were carried out to find out which factors in the drivers' working situation were related to the excretion rate of the working day. The excretion rate of adrenaline on the rest day, age, and psychosomatic complaints were positively related to the excretion rate on the working day (all P < 0.05). Body mass index and physical workload during loading and unloading were positively related to noradrenaline excretion rate (both P < 0.01). Psychosocial job strain did not significantly contribute to the proportion of variance explained in the excretion rates of both catecholamines. CONCLUSIONS: The excretion rates of adrenaline and, especially, noradrenaline on the working day were higher than those found in earlier studies among professional drivers and insufficient recovery took place after the work was ended. The only association between excretion rate on the working day and work stressors was found for noradrenaline and physical workload. The drivers' sympathoadrenal medullary reactivity to everyday work demands shows the characteristics of sustained activation.

Adult↗
PubMed1993

After-effects of night work on physical performance capacity and sleep quality in relation to age.

The after-effects of night work on physical performance capacity and sleep quality were studied. Ten younger (age < or = 34 years) and eight older (age > 34 years) experienced shift workers were examined. Subjects performed cycle ergometer tests at an exercise intensity requiring 70% of the individual maximal oxygen uptake. Two conditions were studied: a baseline condition, i.e. the last day of a 4 days-off period, and a recovery condition after a period of seven consecutive night shifts, i.e. the second day-off after the night-shift period (32 h after leaving the night-shift period). Sleep quality of the sleep period preceding the test was also measured for both conditions. During the recovery condition the endurance time (i.e. time to exhaustion) was reduced by an average of 20% (-160s, P < 0.05) for the older shift workers only. In both age groups exercise ventilation, heart rate, oxygen uptake, perceived exertion and sleep quality remained unaffected. These findings support the hypothesis that the aging shift worker is faced with increasing complaints, even after the night-shift period. However, to clarify the mechanisms responsible for these after-effects of night work, further extensive studies must be designed.

Adult↗