Unpredictable threat increases early event-related potential amplitudes and cardiac acceleration: A brain-heart coupling study.

In the face of unpredictable threat, rapid processing of external events and behavioral mobilization through early psychophysiological responses are crucial for survival. While unpredictable threat generally enhances early processing, it would seem adaptive to particularly increase sensitivity for unexpected events as they may signal danger. To examine this possibility, n = 77 participants performed an auditory oddball paradigm and received unpredictable shocks in threat but not in safe contexts while a stream of frequent (standard) and infrequent (deviant) tones was presented. We assessed event-related potentials (ERP), heart period (HP), and time-lagged within-subject correlations of single-trial EEG and HP (cardio-EEG covariance tracing, CECT) time-locked to the tones. N1 and P2 ERP amplitudes were generally enhanced under threat. The P3 amplitude was enhanced to deviants versus standards and this effect was reduced in the threat condition. Regarding HP, both threat versus safe and unexpected versus expected tones led to stronger cardiac acceleration, suggesting separate effects of threat and stimulus expectancy on HP. Finally, CECTs revealed two correlation clusters, indicating that single-trial EEG magnitudes in the N1/P2 and P3 time-windows predicted subsequent cardiac acceleration. The current results show that an unpredictable threat context enhances N1 and P2 amplitudes and cardiac acceleration to benign auditory stimuli. They further suggest separable cortical correlates of different effects on cardiac activity: an early N1/P2 correlate associated with threat-effects on HP and a later P3 correlate associated with expectedness-effects. Finally, the results indicate that unpredictable threat attenuates rather than enhances the processing of unexpected benign events during the P3 latency.

Evaluating a multimodal, clinical and work-directed intervention (RTW-PIA) to support sustainable return to work among employees with mental disorders: study protocol of a multicentre, randomised controlled trial.

BACKGROUND: Mental disorders (MDs) are one of the leading causes for workforce sickness absence and disability worldwide. The burden, costs and challenges are enormous for the individuals concerned, employers and society at large. Although most MDs are characterised by a high risk of relapse after treatment or by chronic courses, interventions that link medical-psychotherapeutic approaches with work-directed components to facilitate a sustainable return to work (RTW) are rare. This protocol describes the design of a study to evaluate the (cost-)effectiveness and implementation process of a multimodal, clinical and work-directed intervention, called RTW-PIA, aimed at employees with MDs to achieve sustainable RTW in Germany. METHODS: The study consists of an effectiveness, a health-economic and a process evaluation, designed as a two-armed, multicentre, randomised controlled trial, conducted in German psychiatric outpatient clinics. Sick-listed employees with MDs will receive either the 18-month RTW-PIA treatment in conjunction with care as usual, or care as usual only. RTW-PIA consists of a face-to-face individual RTW support, RTW aftercare group meetings, and web-based aftercare. Assessments will be conducted at baseline and 6, 12, 18 and 24 months after completion of baseline survey. The primary outcome is the employees´ achievement of sustainable RTW, defined as reporting less than six weeks of working days missed out due to sickness absence within 12 months after first RTW. Secondary outcomes include health-related quality of life, mental functioning, RTW self-efficacy, overall job satisfaction, severity of mental illness and work ability. The health-economic evaluation will be conducted from a societal and public health care perspective, as well as from the employer's perspective in a cost-benefit analysis. The design will be supplemented by a qualitative effect evaluation using pre- and post-interviews, and a multimethod process evaluation examining various predefined key process indicators from different stakeholder perspectives. DISCUSSION: By applying a comprehensive, multimethodological evaluation design, this study captures various facets of RTW-PIA. In case of promising results for sustainable RTW, RTW-PIA may be integrated into standard care within German psychiatric outpatient clinics. TRIAL REGISTRATION: The study was prospectively registered with the German Clinical Trials Register ( DRKS00026232 , 1 September 2021).