Assessment of Wakefulness and Brain Arousal Regulation in Psychiatric Research

Abstract

tion of wakefulness to the environmental and situational needs so that the optimal balance between energy conservation and responsiveness can be obtained. Since one approach to the assessment of brain arousal regulation is the classification of EEG vigilance stages, a computer-based algorithm (Vigilance Algorithm Leipzig) has been introduced, allowing classification of EEG vigilance stages in EEG recordings under resting conditions. The time course of EEG vigilance stages in EEGs of 15-20 min duration allows estimation of the individual arousal regulation (hyperstable, adaptive, or unstable vigilance pattern). The vigilance model of affective disorders and attention-deficit/hyperactivity disorder links a disturbed arousal regulation to the pathogenesis of psychiatric disorders and accordingly helps to explain and possibly also predict treatment effects of pharmacological and nonpharmacological interventions for these conditions. AbstractDuring the last few decades, much knowledge has been gained about sleep being a heterogeneous condition with several distinct sleep stages that represent fundamentally different physiological states. The same applies for the wake state which also comprises distinct global functional states (called vigilance stages). However, various terms and concepts have been introduced describing different aspects of wakefulness, and accordingly several methods of assessment exist, e.g. sleep laboratory assessments (Multiple Sleep Latency Test, Maintenance of Wakefulness Test), questionnaires (Epworth Sleepiness Scale, Karolinska Sleepiness Scale), behavioural tasks (Psychomotor Vigilance Test) or electroencephalography (EEG)-based assessments (Alpha Attenuation Test, Karolinska Drowsiness Test). Furthermore, several theoretical concepts about the regulation of sleep and wakefulness have been put forward, and physiological correlates have been identified. Most relevant for healthy functioning is the regulation of brain arousal and the adap-

Impact of brain arousal and time-on-task on autonomic nervous system activity in the wake-sleep transition

“…Moreover, arousal and regulatory systems have been posited as a fundamental domain for classifying mental disorders by the Research Domain Criteria Project (RDoC) of the National Institute of Mental Health (NIMH) [15]. In line with this, the Arousal Regulation Model posits a pathophysiological role of brain arousal in affective disorders and attention-deficit/hyperactivity disorder (ADHD) [9, 12, 16, 17]. VIGALL has been utilized in several clinical studies to identify distinct patterns of brain arousal regulation across these psychiatric disorders.…”

Early report on brain arousal regulation in manic vs depressive episodes in bipolar disorder

“…Using EEG measurements, different stages of brain arousal can be discerned in both sleep and wakefulness. The Vigilance Algorithm Leipzig ([VIGALL] http://research.uni-leipzig.de/vigall/) is a tool that automatically and reliably assesses brain arousal stages in wakefulness . It has been validated in several studies relating vigilance stages to simultaneously recorded Blood Oxygenation Level Dependent signals within functional magnetic resonance imaging (fMRI), glucose trapping within positron emission tomography (FDG‐PET) and peripheral signs of autonomic arousal such as heart rate and skin conductance …”

Brain arousal regulation as response predictor for antidepressant therapy in major depression

“…More recently, the assessment of arousal regulation has become a scope of research on antidepressant treatment response171819 and has been defined as a basic and trans-diagnostically relevant neurobiological dimension within the Research Domain Criteria project (RDoC)20. Brain (i.e.…”