We reviewed current definitions of vigilance to propose a definition, applicable in sleep medicine. As previous definitions contained terms such as attention, alertness, and arousal, we addressed... Show moreWe reviewed current definitions of vigilance to propose a definition, applicable in sleep medicine. As previous definitions contained terms such as attention, alertness, and arousal, we addressed these concepts too. We defined alertness as a quantitative measure of the mind state governing sensitivity to stimuli. Arousal comprises a stimulus-induced upward change in alertness, irrespective of the subsequent duration of the increased level of alertness. Vigilance is defined as the capability to be sensitive to potential changes in one's environment, ie the capability to reach a level of alertness above a threshold for a certain period of time rather than the state of alertness itself. It has quantitative and temporal dimensions. Attention adds direction towards a stimulus to alertness, requiring cognitive control: it involves being prepared to process stimuli coming from an expected direction. Sustained attention corresponds to a state in which some level of attention is purposefully maintained, adding a time factor to the definition of attention. Vigilance differs from sustained attention in that the latter in addition implies a direction to which attention is cognitively directed as well as a specification of duration. Attempts to measure vigilance, however, are often in fact measurements of sustained attention. (C) 2021 The Authors. Published by Elsevier B.V. Show less
The locus coeruleus, a small brainstem nucleus, is the main source of the chemical norepineprine in the brain and is involved in a number of cognitive functions as well as several neurological and... Show moreThe locus coeruleus, a small brainstem nucleus, is the main source of the chemical norepineprine in the brain and is involved in a number of cognitive functions as well as several neurological and psychiatric disorders. In this dissertation we study the human LC-NE system, the anatomy of this tiny brainstem nucleus and the involvement of the LC-NE system in stress, arousal, cognitive flexibility and physiology (hormones & pupil responses). To date, the LC-NE system has been studied in animals or ex vivo (dead donors). This dissertation is among the first ones to study and visualize the LC-NE system in humans in vivo (alive volunteers) and to approach the human cognition and the study of the LC-NE system in a holistic manner: from central neuromodulators to hormones that are secreted in the body, from anatomy to physiology and cognition. To this end, all chapters were written by taking into consideration theoretical knowledge about the LC-NE system with regard to brain anatomy, cognitive functions, neuromodulation, physiological responses, and clinical applications. Chapters 2 and 3 deal mainly with the anatomy of the LC, while Chapters 4, 5 and 6 concentrate on cognition and human physiology. Additionally Chapters 5 and 6 take also a clinical approach. Show less
Children spend most of their days interacting with their social environment. Emotions form a large part of these interactions and vice versa social emotions become meaningful when interacting... Show moreChildren spend most of their days interacting with their social environment. Emotions form a large part of these interactions and vice versa social emotions become meaningful when interacting with others. Understanding the emotion processes that underlie successful social functioning is important, especially in children that experience difficulties in social-emotional functioning such as children with Autism Spectrum Disorders (ASD). These studies used a unique approach towards understanding the complex mechanisms that are involved in emotion processing, incorporating how emotions are perceived, experienced, regulated, and expressed. Sensitive and direct measures of emotion processing such as eyetracking and physiology revealed for the first time on a neurobiological level that children with ASD have difficulties emotionally resonating with others, use less efficient strategies to regulate their emotions, and provided evidence for a possible discordance between the expression and experience of emotions. The preschool years also presented with a possible window of opportunity; children with ASD do feel emotions when it comes to their own experiences and the development of social attention towards others might be prone to improvements during the preschool years. These findings are important to parents and professional and enhance the understanding of emotion processing during these very early years of life. Show less
Zantinge, G.M.; Rijn, S. van; Stockmann, L.; Swaab, J.T. 2017
This dissertation explores the involvement of the locus-coeruleus-noradrenaline (LC-NE) system in both temporal attention and uncertainty processing. To this end, a number of cognitive tasks are... Show moreThis dissertation explores the involvement of the locus-coeruleus-noradrenaline (LC-NE) system in both temporal attention and uncertainty processing. To this end, a number of cognitive tasks are used (Stroop, passive viewing, attentional blink, accessory stimulus, auditory oddball) and a number of techniques are utilized (electroencephalogram [EEG], pupillometry, phsychopharmacology). Show less
The studies described in this thesis address a range of topics related to arousal, exploration, temporal attention, and the locus coeruleus-norepinephrine (LC-NE) system. Chapters 2 and 3 report... Show moreThe studies described in this thesis address a range of topics related to arousal, exploration, temporal attention, and the locus coeruleus-norepinephrine (LC-NE) system. Chapters 2 and 3 report two studies that investigated a recent theory about the role of the LC-NE system in the regulation of the exploration-exploitation trade-off. Chapter 4 reports a study on neurocognitive function in patients with dopamine-β-hydroxylase (DβH) deficiency. Chapter 5 reports an fMRI study on the neural correlates of perceptual curiosity. Chapter 6 and 7 reported several experiments investigating the effects of ‘accessory stimuli’ and temporal certainty on information processing, using scalp electrophysiology and sequential-sampling models of decision making. Taken together, the studies reported in this thesis suggest that arousal, exploration and temporal attention are closely related, which is likely due to a shared neural basis. Show less