The psychobiology of burnout: are there two different syndromes?

Background: Plasma prolactin levels are sensitive to dopamine and serotonin function, and fatigue. Low cortisol, dopamine and/or serotonin may be involved in burnout and detachment.

Methods: In this double-blind within-subject study, we treated 9 female burnout subjects and 9 controls with 35 mg cortisol and placebo orally.

Error-related ERP components and individual differences in punishment and reward sensitivity.

Although the focus of the discussion regarding the significance of the error related negatively (ERN/Ne) has been on the cognitive factors reflected in this component, there is now a growing body of research that describes influences of motivation, affective style and other factors of personality on ERN/Ne amplitude. The present study was conducted to further evaluate the relationship between affective style, error related ERP components and their neural basis. Therefore, we had our subjects fill out the Behavioral Activation System/Behavioral Inhibition System (BIS/BAS) scales, which are based on Gray's (1987, 1989) biopsychological theory of personality.

Task engagement and the relationships between the error-related negativity, agreeableness, behavioral shame proneness and cortisol.

Previous results suggest that both cortisol mobilization and the error-related negativity (ERN/Ne) reflect goal engagement, i.e. the mobilization and allocation of attentional and physiological resources.

Mental fatigue, motivation and action monitoring.

In this study we examined whether the effects of mental fatigue on behaviour are due to reduced action monitoring as indexed by the error related negativity (Ne/ERN), N2 and contingent negative variation (CNV) event-related potential (ERP) components. Therefore, we had subjects perform a task, which required a high degree of action monitoring, continuously for 2h. In addition we tried to relate the observed behavioural and electrophysiological changes to motivational processes and individual differences.

Effects of mental fatigue on attention: an ERP study.

The effects of mental fatigue on attention were assessed. Subjects performed a visual attention task for 3 h without rest. Subjective levels of fatigue, performance measures and EEG were recorded.

Acute cortisol administration modulates EEG alpha asymmetry in volunteers: relevance to depression.

The acute effects of cortisol (35mg) administration in 11 healthy male volunteers on resting frontal EEG asymmetry measured in the alpha band were investigated, using a within-subjects double-blind design. Results were indicative of a relative increase of right frontal activity with cortisol. This pattern of activity is similar to the deviant pattern that has been reported in patients suffering from depression, a condition often accompanied by elevated plasma cortisol levels.

Adaptive strategy changes as a function of task demands: a study of car drivers.

When drivers perform additional tasks while driving, research shows conflicting results: primary driving performance may deteriorate but adaptive changes such as reducing driving speed have also been noted. We hypothesized that the nature of the secondary task may be important: drivers may give more priority to tasks that serve goals of the driving task itself, for example route finding, than tasks not directly relevant for driving, for example tuning the radio. The main objective of the present driving simulator study was to test this hypothesis.

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.

Acute cortisol effects on immediate free recall and recognition of nouns depend on stimulus valence.

The present study investigated the acute effects of cortisol administration in normal healthy male volunteers on immediate free recall and recognition of pleasant, unpleasant, and neutral nouns using a between-subjects double-blind design. Two hours after cortisol (10 mg) or placebo administration, impaired recall and recognition of neutral and pleasant words was found in the treatment group, whereas recall and recognition of unpleasant words was similar in both groups. The interaction between treatment and stimulus valence was not mediated by "semantic cohesion," nor does it seem to have been mediated by stimulus arousal.

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.

Mental fatigue and the control of cognitive processes: effects on perseveration and planning.

We tested whether behavioural manifestations of mental fatigue may be linked to compromised executive control, which refers to the ability to regulate perceptual and motor processes for goal-directed behaviour. In complex tasks, compromised executive control may become manifest as decreased flexibility and sub-optimal planning. In the study we use the Wisconsin Card Sorting Test (WCST) and the Tower of London (TOL), which respectively measure flexibility (e.

Motor fatigue and cognitive task performance in humans.

During fatiguing submaximal contractions a constant force production can be obtained at the cost of an increasing central command intensity. Little is known about the interaction between the underlying central mechanisms driving motor behaviour and cognitive functions. To address this issue, subjects performed four tasks: an auditory choice reaction task (CRT), a CRT simultaneously with a fatiguing or a non-fatiguing submaximal muscle contraction task, and a fatiguing submaximal contraction task alone.

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.

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).

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.

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.

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.

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.

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.

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.

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.

Behavioral determinants of occupational exposure to chemical agents.

In the demand-control model (see T. Theorell & R. A.

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).

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.

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.