Background: Electroconvulsive therapy is one of the most effective treatments for major depressive disorder. Recently, there has been increasing attention to evaluate the effect of ECT on resting-state functional magnetic resonance imaging. This study aims to compare rs-fMRI of depressive disorder patients with healthy participants, investigate whether pre-ECT dynamic functional network connectivity network estimated from patients rs-fMRI is associated with an eventual ECT outcome, and explore the effect of ECT on brain network states.Method: Resting-state functional magnetic resonance imaging data were (...) collected from 119 patients with depression or depressive disorder, and 61 healthy participants, with an age mean of 52.25 years old. The pre-ECT and post-ECT Hamilton Depression Rating Scale were 25.59 ± 6.14 and 11.48 ± 9.07, respectively. Twenty-four independent components from default mode and cognitive control network were extracted, using group-independent component analysis from pre-ECT and post-ECT rs-fMRI. Then, the sliding window approach was used to estimate the pre-and post-ECT dFNC of each subject. Next, k-means clustering was separately applied to pre-ECT dFNC and post-ECT dFNC to assess three distinct states from each participant. We calculated the amount of time each subject spends in each state, which is called “occupancy rate” or OCR. Next, we compared OCR values between HC and DEP participants. We also calculated the partial correlation between pre-ECT OCRs and HDRS change while controlling for age, gender, and site. Finally, we evaluated the effectiveness of ECT by comparing pre- and post-ECT OCR of DEP and HC participants.Results: The main findings include depressive disorder patients had significantly lower OCR values than the HC group in state 2, where connectivity between cognitive control network and default mode network was relatively higher than other states, Pre-ECT OCR of state, with more negative connectivity between CCN and DMN components, is linked with the HDRS changes. This means that those DEP patients who spent less time in this state showed more HDRS change, and The post-ECT OCR analysis suggested that ECT increased the amount of time DEP patients spent in state 2.Conclusion: Our finding suggests that dynamic functional network connectivity features, estimated from CCN and DMN, show promise as a predictive biomarker of the ECT outcome of DEP patients. Also, this study identifies a possible underlying mechanism associated with the ECT effect on DEP patients. (shrink)

Individuals make decisions under uncertainty every day. Decisions are based on in- complete information concerning the potential outcome or the predicted likelihood with which events occur. In addition, individuals’ choices often deviate from the rational or mathematically objective solution. Accordingly, the dynamics of human decision making are difficult to capture using conventional, linear mathematical models. Here, we present data from a 2-choice task with variable risk between sure loss and risky loss to illustrate how a simple nonlinear dynamical system can (...) be employed to capture the dynamics of human decision making under uncertainty (i.e., multistability, bifurcations). We test the feasibility of this model quantitatively and demonstrate how the model can account for up to 86% of the observed choice behavior. The implications of using dynamical models for explaining the nonlin- ear complexities of human decision making are discussed as well as the degree to which the theory of nonlinear dynamical systems might offer an alternative framework for understanding human decision making processes. (shrink)

Individuals make decisions under uncertainty every day based on incomplete information concerning the potential outcome of the choice or chance levels. The choices individuals make often deviate from the rational or mathematically objective solution. Accordingly, the dynamics of human decision-making are difficult to capture using conventional, linear mathematical models. Here, we present data from a two-choice task with variable risk between sure loss and risky loss to illustrate how a simple nonlinear dynamical system can be employed to capture the dynamics (...) of human decision-making under uncertainty (i.e., multi-stability, bifurcations). We test the feasibility of this model quantitatively and demonstrate how the model can account for up to 86% of the observed choice behavior. The implications of using dynamical models for explaining the nonlinear complexities of human decision-making are discussed, as well as the degree to which nonlinear dynamical systems theory might offer an alternative framework for understanding human decision-making processes. (shrink)

Dealing with soldier enhancement can be challenging for military physicians. As research on the ethics of soldier enhancement is mostly theoretical, this study aims to gain insights into the actual moral issues military physicians encounter, or expect to encounter. To that end, we carried out a qualitative study involving six focus groups of Dutch military physicians (n = 28) in operational roles. The participants voiced their concerns about moral issues concerning soldier enhancement. Based on the group discussions, and using inductive (...) thematic analysis, we ascertained three major themes: (1) Doing no harm in soldier enhancement: uncertainty and high stakes; (2) Dependency relationships and conflicting moral responsibilities; and (3) The risk of ethical slippery slopes. Our findings illustrate that dealing with these moral responsibilities requires considerable skill and acuity to weigh up for all the situated complexities and dependency relationships that go beyond abstract rules or moral principles. A care-ethical approach that acknowledges the contextual and relational aspects of moral complexities along with peer consultation and joint reflective dialogue on moral issues can help military physicians deal with soldier enhancement responsibly. (shrink)

About one third of patients with epilepsy have seizures refractory to the medical treatment. Electrical stimulation mapping is the gold standard for the identification of “eloquent” areas prior to resection of epileptogenic tissue. However, it is time-consuming and may cause undesired side effects. Broadband gamma activity recorded with extraoperative electrocorticography during cognitive tasks may be an alternative to ESM but until now has not proven of definitive clinical value. Considering their role in cognition, the alpha and beta bands could further (...) improve the identification of eloquent cortex. We compared gamma, alpha and beta activity, and their combinations for the identification of eloquent cortical areas defined by ESM. Ten patients with intractable focal epilepsy participated in a delayed-match-to-sample task, where syllable sounds were compared to visually presented letters. We used a generalized linear model approach to find the optimal weighting of each band for predicting ESM-defined categories and estimated the diagnostic ability by calculating the area under the receiver operating characteristic curve. Gamma activity increased more in eloquent than in non-eloquent areas, whereas alpha and beta power decreased more in eloquent areas. Diagnostic ability of each band was close to 0.7 for all bands but depended on multiple factors including the time period of the cognitive task, the location of the electrodes and the patient’s degree of attention to the stimulus. We show that diagnostic ability can be increased by 3–5% by combining gamma and alpha and by 7.5–11% when gamma and beta were combined. We then show how ECoG power modulation from cognitive testing can be used to map the probability of eloquence in individual patients and how this probability map can be used in clinical settings to optimize ESM planning. We conclude that the combination of gamma and beta power modulation during cognitive testing can contribute to the identification of eloquent areas prior to ESM in patients with refractory focal epilepsy. (shrink)

The objective of the new series, "Molecular Biology, Biochemistry and Biophysics", of which this brochure forms the first volume, is to produce more than another compilation of data. It is hoped that the new series will help the individual "specialist" keep abreast of important developments in the natural sciences at the molecular and subcellular level in fields complementary to his own. The predominant aim is not so much to increase the ever-growing body of information in an encyclopedic fashion but rather (...) to give, in addition to a well rounded factual presentation of subjects which have reached a degree of maturation, a leitmotiv developed by the individual authors from a more personal point of view. The reader should thus be able to use these mono graphs not only for acquisition of knowledge but as a source of further motiva tion in his own work. This latter and more consequential aim of the monograph series is one of the reasons for presenting here a most unusual talk which should enable the reader to sit back and view his own efforts in the context of science and creative attempts as a whole. The lecture is the virtually unknown inaugural address of the Dutch physical chemist JACOBUS HENRICUS VAN'T HOFF. As is shown in his short biography presented on pages 3 and 4 the principal thoughts of the molecular biologist of today are akin to his own and he clearly recognized the universality of molecular life processes. (shrink)

Results of two survey studies are presented. It is shown that attitudes of the public about "technology in general" are not stable and can easily be affected by how the subject is introduced. Eight areas of technology are compared on the basis of empirical relations in attitudinal judgments, in attribute ratings, in self- assigned importance weights of attributes, and in importance of reference groups and persons. On the basis of similarities in these four kinds of judgments, three clusters of technology (...) areas were identified: a cluster of modern reproductive technologies, an information cluster containing automation, computer, and communication technologies, and a cluster containing nuclear energy and military technology. The attitude toward "technology in general" can not be considered as an aggregation of attitudes toward these areas of technology: The relations between general attitude and specific attitudes are only moderate to negligible. (shrink)

Objectives: To investigate why physicians label end-of-life acts as either ‘euthanasia/ending of life’ or ‘alleviation of symptoms/palliative or terminal sedation’, and to study the association of such labelling with intended reporting of these acts. Methods: Questionnaires were sent to a random, stratified sample of 2100 Dutch physicians. They were asked to label six hypothetical end-of-life cases: three ‘standard’ cases and three cases randomly selected, that varied according to type of medication, physician’s intention, type of patient request, patient’s life expectancy and (...) time until death. We identified the extent to which characteristics of cases are associated with physician’s labelling, with multilevel multivariable logistic regression. Results: The characteristics that contributed most to labelling cases as ‘euthanasia/ending of life’ were the administration of muscle relaxants or disproportional morphine. Other important factors were an intention to hasten death and a life expectancy of several months. Physicians were much more willing to report cases labelled as ‘euthanasia’ or ‘ending of life’ than other cases. Conclusions: Similar cases are not uniformly labelled. However, a physicians’ label is strongly associated with their willingness to report their acts. Differences in how physicians label similar acts impede complete societal control. Further education and debate could enhance the level of agreement about what is physician-assisted dying, and thus should be reported, and what not. (shrink)

The Dutch law states that a physician may perform euthanasia according to a written advance euthanasia directive when a patient is incompetent as long as all legal criteria of due care are met. This may also hold for patients with advanced dementia. We investigated the differing opinions of physicians and members of the general public on the acceptability of euthanasia in patients with advanced dementia.

In this article, an ethical analysis of an educational programme on renal replacement therapy options for patients and their social network is presented. The two main spearheads of this approach are: (1) offering an educational programme on all renal replacement therapy options ahead of treatment requirement and (2) a home-based approach involving the family and friends of the patient. Arguments are offered for the ethical justification of this approach by considering the viewpoint of the various stakeholders involved. Finally, reflecting on (...) these ethical considerations, essential conditions for carrying out such a programme are outlined. The goal is to develop an ethically justified and responsible educational programme. (shrink)

Feedback control in neural systems is ubiquitous. Here we study the mathematics of nonlinear feedback control. We compare models in which the input is multiplied by a dynamic gain (multiplicative control) with models in which the input is divided by a dynamic attenuation (divisive control). The gain signal (resp. the attenuation signal) is obtained through a concatenation of an instantaneous nonlinearity and a linear low-pass filter operating on the output of the feedback loop. For input steps, the dynamics of gain (...) and attenuation can be very different, depending on the mathematical form of the nonlinearity and the ordering of the nonlinearity and the filtering in the feedback loop. Further, the dynamics of feedback control can be strongly asymmetrical for increment versus decrement steps of the input. Nevertheless, for each of the models studied, the nonlinearity in the feedback loop can be chosen such that immediately after an input step, the dynamics of feedback control is symmetric with respect to increments versus decrements. Finally, we study the dynamics of the output of the control loops and find conditions under which overshoots and undershoots of the output relative to the steady-state output occur when the models are stimulated with low-pass filtered steps. For small steps at the input, overshoots and undershoots of the output do not occur when the filtering in the control path is faster than the low-pass filtering at the input. For large steps at the input, however, results depend on the model, and for some of the models, multiple overshoots and undershoots can occur even with a fast control path. (shrink)

As part of the Dutch national science program “Professional Games for Professional Skills” we developed a stress-exposure biofeedback training in virtual reality for the Dutch police. We aim to reduce the acute negative impact of stress on performance, as well as long-term consequences for mental health by facilitating physiological stress regulation during a demanding decision task. Conventional biofeedback applications mainly train physiological regulation at rest. This might limit the transfer of the regulation skills to stressful situations. In contrast, we provide (...) the user with the opportunity to practice breathing regulation while they carry out a complex task in VR. This setting poses challenges from a technical – as well as from a user-experience perspective. We illustrate how we approach these challenges in our training and hope to contribute a useful reference for researchers and developers in academia or industry who are interested in using biosignals to control elements in a dynamic virtual environment. (shrink)

It is widely recognized that police performance may be hindered by psychophysiological state changes during acute stress. To address the need for awareness and control of these physiological changes, police academies in many countries have implemented Heart-Rate Variability biofeedback training. Despite these trainings now being widely delivered in classroom setups, they typically lack the arousing action context needed for successful transfer to the operational field, where officers must apply learned skills, particularly when stress levels rise. The study presented here aimed (...) to address this gap by training physiological control skills in an arousing decision-making context. We developed a Virtual-Reality breathing-based biofeedback training in which police officers perform deep and slow diaphragmatic breathing in an engaging game-like action context. This VR game consisted of a selective shoot/don’t shoot game designed to assess response inhibition, an impaired capacity in high arousal situations. Biofeedback was provided based on adherence to a slow breathing pace: the slower and deeper the breathing, the less constrained peripheral vision became, facilitating accurate responses to the in-game demands. A total of nine male police trainers completed 10 sessions over a 4-week period as part of a single-case experimental ABAB study-design. Results showed that eight out of nine participants showed improved breathing control in action, with a positive effect on breathing-induced low frequency HRV, while also improving their in-game behavioral performance. Critically, the breathing-based skill learning transferred to subsequent sessions in which biofeedback was not presented. Importantly, all participants remained highly engaged throughout the training. Altogether, our study showed that our VR environment can be used to train breathing regulation in an arousing and active decision-making context. (shrink)

Mutual perceptions of ethical behaviour among managers in nine EU-countries were quantatively measured and related to perceptions concerning "ease of cooperation". A strong positive correlation obtains: the more ethical a country is perceived to be, the higher it is valued as an international business partner. Germany, however, is a typical exception to this rule: German managers are perceived as the most ethical, but are considered relatively difficult to cooperate with.

This article presents standards for setting up and educating institutional ethics committees (IECs). These standards are based on experiences in the Netherlands, where IECs have been established in a large number of health care institutions. Though the IEC has become a generally accepted institution within Dutch health care, there are concerns over its effectiveness regarding the improving of the moral quality of clinical decision making. Health care practitioners and members of IECs too, experience a gap between the IEC and the (...) reality of the clinical environment. At this moment, there is interest in developing programmes which educate practitioners in moral issues and how to deal with them, using the method of a structured debate on the ward. The IEC will not be made obsolete by this development, but can play a guiding role in the implementation of such programmes. Current concerns are the lack of patient representation in the Dutch IEC, and the loss of contact with the local community of health care practitioners because of the merger of hospitals into bodies similar to UK National Health Service (NHS) trusts. (shrink)